Nigerian Electricity Health And Safety Standards Manual_08!06!08

Nigerian Electricity Health and Safety Standards Manual Nigerian Electricity Regulatory Commission (NERC) Adamawa Plaza, Plot 1099 First Avenue, Central Business District P.M.B 136 Garki, Abuja, Nigeria

Issue Date: Version 1: March 2008

"This publication has been prepared by Princeton Energy Resources International, Inc. on behalf of the Nigerian Electricity Regulatory Commission under a Grant provided by the United States Trade & Development Agency. Copyright 2008 Version 1 Printing No. 1"

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Preface and Acknowledgements

PREFACE The Health and Safety Standards embodied in this document have been developed as a part of a Technical Assistance (TA) project to the Government of Nigeria. The Technical Assistance for the Nigerian Electricity Regulatory Commission Health and Safety Standards Project is a program to the Government of Nigeria (GON) aimed at developing industry-specific health and safety (H&S) standards. The project was funded as a grant (Grant Number GH061136289) by the United States Trade and Development Agency (USTDA) and implemented by Princeton Energy Resources International (PERI), LLC, a U.S. based corporation. The Nigerian Electricity Health and Safety standards created under the assistance program represents a technical reference document with both general and industry-specific examples and guidelines of International Industry Best Practice (IIBP). The industry guidelines are designed to be used to address common safety issues specific to the industry sector; however many sections are potentially applicable to other industry sectors. The power sector in Nigeria is a critical infrastructure needed for the economic, industrial, technological and social development of the Country The World Bank and others have long recognized that electricity consumption is one of the indices for measuring the standard of living of any country. The standards contained herein represent the first major updating of industryspecific safety rules and best practices since the 1980s for the power sector in Nigeria. At the time of preparation of the standards, the national electricity grid consisted of Fifteen generating stations (4 hydro and 11 thermal) with a total installed generating capacity of 7,994MW. Although the installed capacity of the existing power stations is presently 7,994MW, the maximum load ever recorded was 3,774.4MW in August 2005. Presently, many of the generating units have broken down due to limited available resources to carry out maintenance. The transmission lines are radial and overloaded. The switchgears are obsolete while power transformers have not been maintained. The distribution sub-sector is in need of upgrading as many of its distribution transformers are overloaded. Overall transmission and distribution losses are in the range of 30–40%. The electricity network has been characterized by system collapses as a result of low generating capacity by the few generating stations presently in service. For a country of more than 150 million people, the generation capacity is inadequate to meet the consumers’ electricity demand. The current projected capacity that needs to be into the system is estimated at 10,000 MW. It is expected that these would come in through Independent Power Producers (IPPs) as a liberalized Electricity Supply Industry evolves in Nigeria. As the infrastructure expands to meet the needs of Nigeria as a nation, the standards will need to grow and expand. Therefore, the standards themselves should be considered a living document that will be modified, expanded upon and in some instances contracted to meet technological changes in the workforce. Limited accident statistics specific to this sector have only recently been gathered by the Nigerian Electricity Regulatory Commission (NERC); however they reflect monthly fatalities from electrocution in both the public sector and among the sector workforce. These incidents are a direct result of the lack of International Industry Best Practices (IIBP) which technologically advanced nations have had in place and continually improve on. i

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The backbone of the industry is the labor force. The industry sector employs approximately 34,000 people. The country itself has a population of more than 150 million, with about 40% of the population serviced by electricity. The need to protect workers and the general public from the hazards resulting from power generation, transmission, distribution and supply is simply a matter of protecting human life. Workplaces include all places of work; all non-electrical workers and members of the public in public places. Major causes of fatalities in workplaces include plug in appliances and flexible cords and fixed wiring, and maintenance related activities that are specific to the industry sector. Contact with power lines is a significant causative factor of electrical deaths across several of the electrical safety priorities such as workplaces and public places, but it is not the only one. Workplaces even within the industry sector represent a very diverse group of locations, with very different levels of electrical risk. Prioritization of high risk areas needs to be determined based on data, but is likely to include: • • •

the rural sector; the construction sector; and workplaces where water is significantly involved.

The standards focus on all electrical and non-electrical workers engaged to perform work by electricity entities, involved in the generation, transmission or distribution of power in Nigeria. A review of numerous industry reported studies from the sector support that fatalities occurred which could have been prevented by the use of recognized electricity industry safe systems of work. Many more people have been electrocuted when they contacted electricity industry infrastructure such as power lines.

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Preface and Acknowledgements

NOTICE These Standards are designed to save lives. The Nigerian Electric Regulatory Commission has stated its intent to enforce the standards. This means that the practices defined in this publication are legal obligations. Each employer has a legal obligation to ensure that a safe work environment is provided to all employees, both regular and non-regular. Contractors working at substations, transmission stations, power plants or engaging in any work activities involving power generation, transmission, distribution and servicing are also required to follow the best practices and safety standards defined in this publication.

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Preface and Acknowledgements

ACKNOWLEDGEMENTS A large number of organizations and individuals have contributed time and information that went into the creation of the standards. The following organizations are expressly thanked for their contribution of materials, reviews, critiques and guidance: The U.S. Trade and Development Agency The World Bank Organization The U.S. Department of Energy The U.S. Department of Defense The U.S. Department of Homeland Security The World Health Organization The U.S. Occupational Safety and Health Organization The National Institute of Occupational Safety and Health The American Conference of Governmental Industrial Hygienists Gulf Publishing Co. Marcel Dekker Publishers SciTech Technical Services The Nigerian Electricity Regulatory Commission Tennessee Valley Authority The U.S. Department of Agriculture, Rural Utilities Service U. S. Embassy in Nigeria Power Holding Company of Nigeria (PHCN) Transmission Company of Nigeria (TCN)

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Preface and Acknowledgements

ABBREVIATIONS AC: Alternating Current (electricity; physics) ACGIH: American Conference of Governmental Industrial Hygienists AED: Automated Eternal Defibrillator AFFF: Aqueous Film Forming Foam AFS: American Foundry Society AIHI: American Industrial Hygiene Association ANSI: American National Standards Institute ASTDR: Agency for Toxic Substances and Disease Registry ASTM: American Society for Testing and Materials ATB: Anti-Two-Block AU: Absorption Units C: Celsius CaF: Calcium Fluoride CDC: Center for Disease Control CERCLA: Comprehensive Environmental Response Compensation and Liability Act CGA: Compressed Gas Association CGI: Combustible Gas Indicators CISD: Critical Incident Stress Debriefing Cm: Centimeters CNC: Condensation Nucleus Counter CO: Carbon monoxide CO2: Carbon Dioxide CPR: Cardiopulmonary Resuscitation CSA: Construction Safety Association CSHO: Compliance Safety and Health Officer dB: Decibels DC: Direct Current (electricity) DUTs: Devices Under Test EAR: Expired Air Resuscitation EHSS: Environmental Health and Safety Services EHV: Extremely High Voltage EMS: Emergency Medical Services EPA: Environmental Protection Agency EPS: Electric Power Systems ESCBA: Escape Self-Contained Breathing Apparatus ESLI: End of Service Life Indicator FID: Flame Ionization Detector FMIS: Facilities Management Information System GFCI: Ground Fault Circuit Interrupter GHz: Gigahertz (thousands of MHz) GM: Geiger-Muller H2S: Hydrogen Sulfide HASPs: Health and Safety Plans HAZWOPEP: Hazardous Waste Operations and Emergency Response vii

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HEPA: High Efficiency Particulate Air Hg: Mercury HR: Human Resource HRT: Health Response Team HSC: Health and Safety Coordinator HSO: Health and Safety Officer HV: High Voltage Hz: Hertz IDLH: Immediately Dangerous to Life and Health Kg: Kilograms kHz: Kilohertz (1000 Hertz) kPa: Kilo Pascal LEL: Lower Explosive Limit LFL: Lower Flammable Limit LiF: Lithium Fluoride LMI: Load moment Indicators m: Meters MeV: Mega Electron Volt MHz: Megahertz (million Hertz) mR/hr: Milliroentgen Per Hour MRLS: Minimal Risk Levels MSDS: Material Safety Data Sheets MUC: Maximum Use Concentration MW: Molecular Weight NEPA: National Fire Protection Agency NERC: North American Electric Liability Corporation NHCA: National Hearing Conservation Association NIOSH: National Institute of Occupational Safety and Health NO: Nitric oxide NRR: Noise Reduction Rating NRTL: Nationally Recognized Testing Laboratories NTOF: National Traumatic Occupational Facilities O3: Ozone OH&S: Occupational Health and Safety OSHA: Office of Safety and Health Administration Pa: Pascal PAPR: Powered Air Purifying Respirator PEL: Permissible Exposure Limits PID: Photo Ionization Detectors PM: Particulate Matter PPE: Personal Protective Equipment ppm: Parts Per Million PVC: polyvinyl chloride QLFT: Qualitative Fit Test QNFT: Quantitative Fit Test RCRA: Resource Conservation and Recovery Acts

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REL: Recommended Exposure Limits RF: Radiated Frequency RFC: Reference Concentration RFD: Reference Dose R/hr: Roentgens per Hour RH: Relative Humidity SA: Spectrum Analyzer SAR: Supplied Air Respirator SARA: Superfund Amendments and Reauthorization Act SCBA: Self-Contained Breathing Apparatus SHELS: Significant Human Exposure Levels SLTC: Salt Lake Technical Center SO2: Sulfur dioxide SPL: Sound Pressure Level STEL: Short-term Exposure Limits SVOCs: Semi-Volatile Organic Compounds TD: Thermal Desorption TICs: Toxicity Identified Compounds TLD: Thermoluminescent dosimeters TLV: Threshold Limit Value TWA: Time Weighted Average UEL: Upper Explosive Limits U.K.: United Kingdom U.S.: United States UV: Ultraviolet VOCs: Volatile Organic Compound VOM: Colt-Ohm-Milliameter VSA: Vector Signal Analyzer WHO: World Health Organization

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Preface and Acknowledgements

DOCUMENT RETENTION POLICY AND PROCEDURE TO MAINTAINING UP-TO-DATE STANDARDS As stated in the Preface, the changing landscape of technologies and IPPs planned for Nigeria require the standards to be flexible to meet future safety challenges. As such, the publication should be viewed as a living document that will require periodic review and updates. NERC will form a committee to review the standards every three years and make a formal recommendation as to whether Parts, Sections, or individual Paragraphs require revisions. They will then form an appropriate task force to make the revisions and to update the publication. If no changes are recommended, NERC will publish a statement to that effect on its web site. If changes are to be made, NERC will submit drafts of the standards for review and comment by the industry with a reasonable response time. Each page of the publication states the Version and date of Issuance in the Header. In this first printing, the reader will see Version 1: March 2008. Subsequent revisions will state Revision 1: Date; Revision 2: Date; and so forth. Owners of the publication may replace those pages with subsequent revisions. NERC will retain one or more copies of the each Version and Revision on permanent file in order to preserve the evolution of the standards.

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Preface and Acknowledgements

FOREWORD AND ORGANIZATION OF THE STANDARDS The standards represent legal obligations. Not all of the standards are applicable or enforceable at every facility. Each facility must make an assessment as to which of the standards are applicable. This can be made by performing a job classification and hazards assessment and by consulting with NERC. The standards are organized into five Parts: Part I. How to Evaluate Safety Programs; Part II. Safety and Best Industry Practices; Part III. Worker Safety Rules; Part IV. Recordkeeping, Training, Inspections, Accident Investigation and Reporting; Part V. Risk and Vulnerability Assessments Each Part contains sections and subsections. For related topics, cross-referencing between Parts and individual Sections are provided. Users are likely to refer to Part II most extensively. These contain technical safety work standards.

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TABLE OF CONTENTS PREFACE ........................................................................................................................................ i NOTICE......................................................................................................................................... iii ACKNOWLEDGEMENTS............................................................................................................ v ABBREVIATIONS ...................................................................................................................... vii DOCUMENT RETENTION POLICY AND PROCEDURE TO MAINTAINING UP-TO-DATE STANDARDS....................................................................................................... xi FOREWORD AND ORGANIZATION OF THE STANDARDS .............................................. xiii PART I. HOW TO EVALUATE SAFETY PROGRAMS 1(a) Introduction ...........................................................................................................................I-3 1(b) Creating a Culture of Safety..................................................................................................I-3 1(c) Good Housekeeping ..............................................................................................................I-9 1(d) New Employee Orientation.................................................................................................I-14 1(e) Worker Rights .....................................................................................................................I-21 PART II. SAFETY AND BEST INDUSTRY PRACTICES SEC. 2(a) AIR QUALITY TESTING AND MONITORING .................................................... II-7 2(a)(1) Introduction..................................................................................................................... II-9 2(a)(2) Methods of Sampling and Testing .................................................................................. II-9 2(a)(3) Samplers and Monitors ................................................................................................. II-10 2(a)(4) Batteries ........................................................................................................................ II-19 2(a)(5) Adverse Conditions....................................................................................................... II-20 2(a)(6) Appendix - Instrument Chart ........................................................................................ II-21 2(a)(7) Bibliography ................................................................................................................. II-21 SEC. 2(b) NOISE TESTING AND MONITORING................................................................ II-23 2(b)(1) Introduction .................................................................................................................. II-25 2(b)(2) Noise Monitors and Meters .......................................................................................... II-25 2(b)(3) Occupational Noise Exposure Standard ....................................................................... II-27 2(b)(4) Bibliography ................................................................................................................. II-32 SEC. 2(c) RADIATION MONITORS AND METERS ........................................................... II-35 2(c)(1) Introduction................................................................................................................... II-37 2(c)(2) Light.............................................................................................................................. II-37 2(c)(3) Ionizing Radiation......................................................................................................... II-38 2(c)(4) Nonionizing Radiation.................................................................................................. II-38 2(c)(5) Survey Meters for Radiation Detection ........................................................................ II-39 2(c)(6) Pocket Dosimeters ........................................................................................................ II-41 2(c)(7) Audible Alarm Rate Meters and Digital Electronic Dosimeters .................................. II-43 2(c)(8) Film Badges .................................................................................................................. II-43 2(c)(9) Thermoluminescent Dosimeters ................................................................................... II-44 2(c)(10) Annex – Guide to Meter Selection and Applications ................................................. II-44

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2(c)(11) Bibliography ............................................................................................................... II-46 SEC. 2(d) ELECTRICAL/ELECTRONICS TESTING METERS .......................................... II-49 2(d)(1) Introduction .................................................................................................................. II-51 2(d)(2) Electronic Test Equipment Types................................................................................. II-51 2(d)(3) General Information on Safe Use ................................................................................. II-53 SEC. 2(e) SAFE CHEMICAL HANDLING ............................................................................ II-55 2(e)(1) Introduction................................................................................................................... II-57 2(e)(2) Reference Standards ..................................................................................................... II-57 2(e)(3) Safe Chemical Exposure Tables ................................................................................... II-90 SEC. 2(f) JOB HAZARDS ANALYSIS ASSESSMENT...................................................... II-179 2(f)(1) Introduction ................................................................................................................. II-181 2(f)(2) Responsibility and Tailgate Meetings ......................................................................... II-181 2(f)(3) Hazards Assessment.................................................................................................... II-182 2(f)(4) Hazard Assessment and PPE Checklists ..................................................................... II-191 2(f)(5) Bibliography................................................................................................................ II-200 SEC. 2(g) PERSONAL PROTECTIVE EQUIPMENT ......................................................... II-201 2(g)(1) Introduction ................................................................................................................ II-203 2(g)(2) General Provisions...................................................................................................... II-203 2(g)(3) Requirements of a PPE Program ................................................................................ II-203 2(g)(4) Guidelines for PPE Selection ..................................................................................... II-205 2(g)(5) Worker Training ......................................................................................................... II-205 2(g)(6) Eye and Face Protection ............................................................................................. II-206 2(g)(7) Head Protection .......................................................................................................... II-208 2(g)(8) Foot and Leg Protection ............................................................................................. II-209 2(g)(9) Hand and Arm Protection ........................................................................................... II-210 2(g)(10) Protective Equipment for the Body .......................................................................... II-214 2(g)(11) Hearing Protection.................................................................................................... II-214 2(g)(12) Respiratory Protection .............................................................................................. II-215 2(g)(13) Bibliography ............................................................................................................. II-227 SEC. 2(h) FIRST AID AND RESUSCITATION................................................................... II-229 2(h)(1) Introduction ................................................................................................................ II-231 2(h)(2) First Aid Assessments ................................................................................................ II-231 2(h)(3) Elements of a First Aid Training Program ................................................................. II-232 2(h)(4) Periodic Program Updates .......................................................................................... II-235 2(h)(5) First Aiders ................................................................................................................. II-235 2(h)(6) First Aid Training and Certification ........................................................................... II-235 2(h)(7) First Aid for Electric Shock........................................................................................ II-236 2(h)(8) Skills Update............................................................................................................... II-237 2(h)(9) First Aid Supplies ....................................................................................................... II-237 2(h)(10) Bibliography ............................................................................................................. II-238

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SEC. 2(i) FIRE PROTECTION, EVACUATION, FIRST RESPONDER AND EMERGENCY PLANNING ......................................................................................... II-239 2(i)(1) Flammability Properties .............................................................................................. II-241 2(i)(2) Ignition Temperature ................................................................................................... II-246 2(i)(3) Flammability Limits .................................................................................................... II-247 2(i)(4) Vapor Density.............................................................................................................. II-249 2(i)(5) Specific Gravity........................................................................................................... II-250 2(i)(6) Water Solubility........................................................................................................... II-250 2(i)(7) Responding to Fires..................................................................................................... II-251 2(i)(8) Fire Fighting Agents.................................................................................................... II-254 2(i)(9) Electrical Fire Prevention ............................................................................................ II-258 2(i)(10) Firefighting Guidance................................................................................................ II-259 2(i)(11) Specialized Rescue Procedures ................................................................................. II-264 2(i)(12) First Responder to Electrical Fire Incidents .............................................................. II-265 2(i)(13) Evacuation Planning.................................................................................................. II-266 2(i)(14) Bibliography .............................................................................................................. II-270 SEC. 2(j) ELECTRIC SHOCK AND LOCKOUT/TAGOUT ............................................... II-271 2(j)(1) Introduction ................................................................................................................. II-273 2(j)(2) Fuses ............................................................................................................................ II-273 2(j)(3) GFCIs .......................................................................................................................... II-273 2(j)(4) Electrical Shock........................................................................................................... II-274 2(j)(5) Feedback Electrical Energy......................................................................................... II-276 2(j)(6) Universal Precautions.................................................................................................. II-276 2(j)(7) Training Programs ....................................................................................................... II-276 2(j)(8) Protective Equipment and Work Practices .................................................................. II-276 2(j)(9) Detection of Low Voltage ........................................................................................... II-277 2(j)(10) Lockout/Tagout ......................................................................................................... II-277 2(j)(11) Lockout Devices........................................................................................................ II-279 2(j)(12) Specific Procedures for Logout/Tagout..................................................................... II-279 2(j)(13) Bibliography .............................................................................................................. II-281 SEC. 2(k) HAND TOOLS AND WORKSHOP MACHINES ............................................... II-283 2(k)(1) Introduction ................................................................................................................ II-285 2(k)(2) What Are the Hazards of Hand Tools?....................................................................... II-285 2(k)(3) What Are the Dangers of Power Tools?..................................................................... II-286 2(k)(4) Guards......................................................................................................................... II-286 2(k)(5) Operating Controls and Switches ............................................................................... II-287 2(k)(6) Electric Tools.............................................................................................................. II-287 2(k)(7) Portable Abrasive Wheel Tools.................................................................................. II-288 2(k)(8) Pneumatic Tools ......................................................................................................... II-289 2(k)(9) Liquid Fuel Tools ....................................................................................................... II-290 2(k)(10) Powder-Actuated Tools ............................................................................................ II-290 2(k)(11) Hydraulic Power Tools............................................................................................. II-291 2(k)(12) General Requirements of Safety in Workshops Policy ............................................ II-292 2(k)(13) Machinery Installation.............................................................................................. II-293

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2(k)(14) Machine Controls ..................................................................................................... II-293 2(k)(15) Machine Guards........................................................................................................ II-293 2(k)(16) Service Installations.................................................................................................. II-293 2(k)(17) Grinding and Polishing Machines ............................................................................ II-294 2(k)(18) Milling Machines...................................................................................................... II-294 2(k)(19) Metal-Cutting Guillotines......................................................................................... II-295 2(k)(20) General Considerations............................................................................................. II-295 2(k)(21) Solvent Degreasing................................................................................................... II-296 2(k)(22) Bibliography ............................................................................................................. II-296 SEC. 2(l) LINEMEN GENERAL SAFETY PRACTICES .................................................... II-297 2(l)(1) Introduction ................................................................................................................. II-299 2(l)(2) Scope ........................................................................................................................... II-299 2(l)(3) Shock Hazard Analysis................................................................................................ II-299 2(l)(4) Regulatory Issues......................................................................................................... II-300 2(l)(5) Standard Requirements................................................................................................ II-300 2(l)(6) Test Equipment Industry Recognized Good Practices ............................................... II-300 2(l)(7) Flash Hazard Analysis................................................................................................. II-301 2(l)(8) Blast Hazard Analysis ................................................................................................. II-301 2(l)(9) Selection of Electrical Protective Equipment.............................................................. II-302 2(l)(10) Exterior Safety Rules................................................................................................. II-303 2(l)(11) Exterior Working Practices ....................................................................................... II-306 2(l)(12) Electrical Safety Rules .............................................................................................. II-308 2(l)(13) Transformers and Circuit Breakers ........................................................................... II-312 2(l)(14) Wire Markers............................................................................................................. II-313 2(l)(15) Adequacy and Effectiveness of the Training Program ............................................. II-313 2(l)(16) Bibliography .............................................................................................................. II-314 SEC. 2(m) ELECTRICAL SAFE WORK PRACTICES PLAN ............................................ II-315 2(m)(1) Introduction ............................................................................................................... II-317 2(m)(2) Training ..................................................................................................................... II-317 2(m)(3) Qualified Person ........................................................................................................ II-317 2(m)(4) Safe Work Practices .................................................................................................. II-317 SEC. 2(n) ELECTRICAL EQUIPMENT ............................................................................... II-323 2(n)(1) Introduction ................................................................................................................ II-325 2(n)(2) Electrical Safety Facts ................................................................................................ II-325 2(n)(3) Vehicular and Mechanical Equipment ....................................................................... II-326 2(n)(4) Use of Equipment ....................................................................................................... II-327 2(n)(5) Test Equipment........................................................................................................... II-328 2(n)(6) Bibliography ............................................................................................................... II-328 SEC. 2(o) LADDER SAFETY ............................................................................................... II-329 2(o)(1) Introduction ................................................................................................................ II-331 2(o)(2) General Requirements ................................................................................................ II-331 2(o)(3) Ladder Hazards/Prevention Tips ............................................................................... II-336

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2(o)(4) Ladder Selection ......................................................................................................... II-336 2(o)(5) Ladder Maintenance ................................................................................................... II-336 2(o)(6) Ladder Inspections...................................................................................................... II-338 2(o)(7) Bibliography ............................................................................................................... II-339 SEC. 2(p) FORKLIFT SAFETY ............................................................................................ II-341 2(p)(1) Introduction ................................................................................................................ II-343 2(p)(2) Pre-Qualifications for Forklift Operators ................................................................... II-343 2(p)(3) Safe Operating Procedures ......................................................................................... II-343 2(p)(4) Changing and Charging Storage Batteries.................................................................. II-344 2(p)(5) Operations................................................................................................................... II-344 2(p)(6) Traveling..................................................................................................................... II-345 2(p)(7) Loading....................................................................................................................... II-345 2(p)(8) Fueling ........................................................................................................................ II-345 2(p)(9) Maintenance................................................................................................................ II-346 2(p)(10) Training .................................................................................................................... II-346 2(p)(11) Refresher Training and Evaluation........................................................................... II-347 2(p)(12) Bibliography ............................................................................................................. II-348 SEC. 2(q) CRANE OPERATION SAFETY .......................................................................... II-349 2(q)(1) Lifting Principles ........................................................................................................ II-351 2(q)(2) Operational Considerations ........................................................................................ II-352 2(q)(3) Construction Requirements ........................................................................................ II-352 2(q)(4) Inspection Guidelines ................................................................................................. II-353 2(q)(5) Definitions .................................................................................................................. II-366 2(q)(6) Bibliography ............................................................................................................... II-368 SEC. 2(r) SCAFFOLDS AND OTHER WORK PLATFORMS............................................ II-369 2(r)(1) Introduction ................................................................................................................. II-371 2(r)(2) Scaffold Safety ............................................................................................................ II-371 2(r)(3) Bibliography................................................................................................................ II-380 SEC. 2(s) SAFE WORK PRACTICES NEAR POWER LINES ........................................... II-381 2(s)(1) Introduction................................................................................................................. II-383 2(s)(2) Plan Ahead .................................................................................................................. II-383 2(s)(3) Safe Work Practices .................................................................................................... II-383 2(s)(4) Bibliography................................................................................................................ II-388 SEC. 2(t) FUNCTIONAL SAFETY FOR ELECTRIC POWER TRANSMISSION ............ II-391 2(t)(1) Introduction ................................................................................................................. II-393 2(t)(2) Structure of Electric Power Systems ........................................................................... II-393 2(t)(3) Hazards in Electric Power Systems............................................................................. II-394 2(t)(4) Assuring Functional Safety ......................................................................................... II-397 2(t)(5) Recommended References .......................................................................................... II-397

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SEC. 2(u) EXCAVATIONS AND TRENCHING ................................................................. II-399 2(u)(1) Introduction ................................................................................................................ II-401 2(u)(2) Recommended Practices............................................................................................. II-401 2(u)(3) Safety Guidelines........................................................................................................ II-403 2(u)(4) Excavation and Trenching Safety Program ................................................................ II-404 2(u)(5) Requirements for Protective Systems......................................................................... II-415 2(u)(6) Definitions .................................................................................................................. II-417 2(u)(7) Bibliography ............................................................................................................... II-419 SEC. 2(v) CONFINED SPACES............................................................................................ II-421 2(v)(1) Identifying Confined Spaces ...................................................................................... II-423 2(v)(2) Identifying Confined Space Hazards.......................................................................... II-424 2(v)(3) Model Confined Space Entry Program....................................................................... II-426 2(v)(4) Personnel Responsibilities and Training .................................................................... II-431 2(v)(5) Definitions .................................................................................................................. II-434 2(v)(6) Bibliography ............................................................................................................... II-436 APPENDIX A: Copy of Confined Space Entry Permit.......................................................... II-437 APPENDIX B: Pre-Entry Planning Worksheet...................................................................... II-440 SEC. 2(w) COMPRESSED GAS CYLINDER SAFETY ...................................................... II-443 2(w)(1) Introduction................................................................................................................ II-445 2(w)(2) Identification.............................................................................................................. II-445 2(w)(3) Handling & Use ......................................................................................................... II-446 2(w)(4) Transportation of Cylinders....................................................................................... II-449 2(w)(5) Bibliography .............................................................................................................. II-449 SEC. 2(x) DRUM HANDLING SAFETY ............................................................................. II-451 2(x)(1) Introduction ................................................................................................................ II-453 2(x)(2) Types of Drums .......................................................................................................... II-454 2(x)(3) Drum Inspection, Handling, and Staging Inspection.................................................. II-455 2(x)(4) Leaking, Open, and Deteriorated Drums.................................................................... II-456 2(x)(5) Preventing Back Injuries ............................................................................................ II-458 SEC. 2(y) SAFE WELDING PRACTICES............................................................................ II-459 2(y)(1) Identifying Safe Welding Practices ............................................................................ II-461 2(y)(2) Definitions .................................................................................................................. II-461 2(y)(3) General Provisions...................................................................................................... II-461 2(y)(4) Inspections .................................................................................................................. II-464 2(y)(5) Ventilation Guidelines for Welding Operations......................................................... II-464 PART III. WORKER SAFETY RULES 3(a) Critical Incident Stress ....................................................................................................... III-5 3(b) Toxic Industrial Chemicals ................................................................................................III-6 3(c) Electrical Protective Devices.............................................................................................. III-9 3(d) Hand Protection................................................................................................................ III-15

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3(e) Hazard Assessment and Personal Protective Equipment Selection ................................. III-15 3(f) Sanitation .......................................................................................................................... III-21 3(g) Safety Color Code for Marking Physical Hazards ........................................................... III-25 3(h) Specifications for Accident Prevention Signs and Tags .................................................. III-25 3(i) Permits for Confined Spaces............................................................................................. III-28 3(j) Control of Hazardous Energy (Lockout/Tagout) .............................................................. III-42 3(k) Medical Services and First Aid ........................................................................................ III-50 3(l) Fire Protection................................................................................................................... III-50 3(m) Handling Materials.......................................................................................................... III-56 3(n) Slings................................................................................................................................ III-57 3(o) Bibliography..................................................................................................................... III-62 Annex A Accident Investigation.............................................................................................. III-65 Annex B Electrical Switching Operation............................................................................... III-153 Annex C Temporary Protective Grounding for Generating Stations and Other Non-Transmission Facilities ................................................................................... III-157 Annex D Guarding Energized Electrical Equipment............................................................. III-179 Annex E Jumpers ................................................................................................................... III-183 Annex F Portable Electric Tools and Attachments ............................................................... III-187 Annex G Safe Distribution Systems ...................................................................................... III-195 Annex H Temporary Lighting ............................................................................................... III-199 Annex I Vehicle Operations Near Energized Lines or Equipment........................................ III-203 Annex J Responsibilities and General Requirements for Transmission Employees ............. III-209 Annex K Transmission/Substation/Telecommunication ....................................................... III-223 Annex L Specifications and Drawings for Underground Electric Distribution..................... III-275 PART IV. RECORDKEEPING, TRAINING, INSPECTIONS, ACCIDENT INVESTIGATION AND REPORTING 4(a) Introduction ........................................................................................................................IV-3 4(b) Safety Recordkeeping Practices and Protocols ..................................................................IV-3 4(c) Accident Recordkeeping Forms .........................................................................................IV-6 4(d) Safety Training and Recordkeeping.................................................................................IV-10 4(e) OHSAS 18001 (Occupation Health and Safety Assessment Series)................................IV-13 4(f) Bibliography .....................................................................................................................IV-15 PART V. RISK AND VULNERABILITY ASSESSMENTS 5(a) Risk Management................................................................................................................ V-3 5(b) Crisis Management............................................................................................................ V-10 5(c) Vulnerability Assessments ................................................................................................ V-12

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PART I HOW TO EVALUATE SAFETY PROGRAMS CONTENTS 1(a) Introduction ........................................................................................................................ I-3 1(b) Creating a Culture of Safety ............................................................................................. I-3 1(c) Good Housekeeping............................................................................................................ I-9 1(c)(1) General Information......................................................................................................I-9 1(c)(2) Establishing a Good Housekeeping Program ...............................................................I-9 1(c)(2)(i) Dust and Dirt Removal .......................................................................................I-11 1(c)(2)(ii) Employee Facilities............................................................................................I-12 1(c)(2)(iii) Surfaces.............................................................................................................I-12 1(c)(2)(iv) Maintain Light Fixtures ....................................................................................I-13 1(c)(2)(v) Aisles and Stairways ..........................................................................................I-13 1(c)(2)(vi) Spill Control......................................................................................................I-13 1(c)(2)(vii) Tools and Equipment .......................................................................................I-13 1(c)(2)(viii) Maintenance....................................................................................................I-13 1(c)(2)(ix) Waste Disposal..................................................................................................I-14 1(c)(2)(x) Storage................................................................................................................I-14 1(d) New Employee Orientation ............................................................................................. I-14 1(e) Worker Rights .................................................................................................................. I-21

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1(a) Introduction This Part of the Standards provides a roadmap for both Employers and Employees to creating a safe working environment. While the Standards in Parts 2 and 3 are organized and presented in a highly prescriptive format, this first Part provides workers within the industry an overall orientation to the philosophy, tools and corporate culture that the international community has adopted as a part of best management practices. At the same time, this Part of the Standards explicitly defines the Rights of Workers to be kept informed of the hazards associated with their job assignments, to be provided with knowledge, engineering and management controls that eliminate unsafe working conditions, along with the actions that workers may take in order to ensure that they are never placed in situations that pose either immediate or long-term risks to their health and well-being. Employees generally have little or no control over their working environment and must accept whatever environment employers offer. NERC is currently attempting to define and establish criteria for acceptable working environments, with the first step being the standards provided herein. Employers and their designated corporate representatives have both a moral and legal obligation to ensure that both workers and the public at large are kept insulated from the hazards associated with the industry sector. 1(b) Creating a Culture of Safety The design of a safe plant layout is beyond the responsibility of individual employees, but it nevertheless is essential for good power production practices and safe working conditions. Narrow aisles, blind intersections, insufficient overhead space and limited access for equipment repair and maintenance all are detrimental to a safe operating environment. The National Safety Council in the United States has estimated that work-related accidents in the private sector in 1988 cost industry an average of $15,100 per disabling injury. Based on this figure and the U.S. Bureau of Labor Statistics – which reported that in 1988 private U.S. Industry, employing 90 million workers, had 6.2 million job-related accidents and injuries was in excess of $93 billion. Approximately, half of this total ($46 billion) was for such visible costs as damaged equipment and materials, production delays, time losses of other workers not involved in the accidents and accident reporting. Similar statistics have been reported in the United Kingdom (UK) and in the European Community. The statistics support the premise that it is the responsibility of every employer to take a strong, proactive stance to ensure their employees’ safety. Designing for safe work environments also means proper scheduling of work activities. It should not be the operator's or worker’s responsibility to determine the proper routing of work in process. To make this type of decision a worker’s responsibility unfairly shifts to what is truly management's responsibility directly to the worker. It is Management’s responsibility to ensure that tight work standards are not only defined for each operating facility, but to ensure that procedures and policies are adopted and enforced. Establishing fair work standards through work measurement or some similar technique is, without question, a prerogative and a right of management. Establishing and enforcing tight work standards has resulted and will continue to I-3

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result in operators taking dangerous short cuts while completing tasks. These short cuts often result in industrial accidents and injuries. By the same token, Managers should use standards to ensure a fair day's pay for a fair day's work, but they should not use them as a whip to achieve maximum productivity through coercion. Pressure placed on employees to meet tight production schedules results in the same type of problems as with tight work standards. Reasonable schedules based on reasonable capacity determinations and work standards eliminate the pressure and work-related stress placed on employees to overproduce because of unsafe short cuts. Having a corporate culture that promotes and makes safety and environment a priority should be the goal of the industry. Creating a culture of safety first requires site-specific work practices and working environments to be carefully assessed with a focus on identifying high-risk areas, and then developing concrete plans for improved occupational and process safety performance. Management must focus on using employee insights to prevent costly and potentially deadly accidents before they occur, creating a safer workplace by taking into account both the environment in which employees work and the culture that drives their daily work experience. As an Employer, it is your responsibility to provide a safe work environment for all employees, free from any hazards, and complying with legal and recommended best practices defined in the Standards. Health and safety in the workplace is about preventing work-related injury and disease, and designing an environment that promotes well-being for everyone at work. Knowledge is the key ingredient in providing a safe work environment. If everyone knows the correct procedures, accidents and injuries will be kept to a minimum. Both Employers and Employees should: • • •

Ensure that the way work is done is safe and does not affect employees’ health. Ensure that tools, equipment and machinery are safe and are kept safe. Ensure that ways of storing, transporting or working with dangerous substances is safe and does not damage employees’ health.

Employers must: • • •

Provide employees with the information, instruction and training they need to do their job safely and without damaging their health. Consult with employees about health and safety in the workplace. Monitor the work place regularly and keep a record of what is found during these checks.

Policies should be developed in consultation with employees, both with and without disability. It may be necessary to organize support persons or interpreters so that all employees may participate in the consultation. Occupational Health and Safety (OH&S) procedures must be implemented wherever the work is being conducted, be that in an office, factory, construction site, substation, along transmission

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line work or home. As an employer, it is your responsibility to ensure all employees have access to information about safety procedures, and for any reasonable adjustments to be made. It is crucial that New employees be: • • •

Briefed of all new staff on OH&S policy at induction. Be provided training on all safety procedures, including evacuation and other emergency procedures. Provided access to information about safety procedures, in appropriate formats.

It is crucial the Existing employees: • • • •

Have access to information in appropriate formats. Be provided with regular information updates and re-training sessions. Be provided access to information about safety procedures. Conduct relevant training on any new equipment or machinery.

The following are some anecdotal facts that can serve to raise a culture of safety among workers and management: Factors that make new workers more accident prone: • Lack of safety training; • Don’t ask questions; • Unaware of hazards; • Assume employer is responsible for safety; • Don’t understand rights/responsibilities; • “It can’t happen to me” attitude; and • Fatigue. Major Causes of Injury: • Slips, trips and falls; • Improper use of equipment; • Faulty use of equipment; • Improper lighting; • Not tuning off power while repairing equipment (lock out procedures); • Entering unsafe confined spaces that do not normally accommodate people; and • Improper use or storage of chemicals and other hazardous materials. The Employer’s Responsibilities: • Provide a safe workplace. • Ensure adequate training of workers. • Keep written records of training: who, when and what type. • Establish and maintain a comprehensive occupational safety program, including a written safety policy and an accident investigation program. • Support supervisors, safety coordinators, and workers in their safety activities. I-5

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Take action immediately when the worker or supervisor tells you about a potentially hazardous situation. Initiate an immediate investigation into accidents. Report serious accidents to the HSO (Health and Safety Officer) or to the Corporate Prevention Division. Provide adequate first Aid facilities and services. Provide personal protective equipment where required. Make available to all workers copies of Industrial Hygiene Policy. Post Health and Safety Regulations and all other regulations.

The Supervisor’s Responsibilities: • Instruct new workers on safe work procedures. • Train workers for all tasks assigned to them and check their progress. • Ensure that only authorized, adequately trained workers operate tools & equipment and use hazardous chemicals. • Ensure that equipment and materials are properly handled, stored and maintained. • Enforce safety regulations. • Correct unsafe acts. • Identify workers with problems such as drugs or alcohol that could affect their performance, and follow up with interviews and referrals where necessary. • Formulate safety rules and inspect for hazards in your own area. Worker’s Responsibilities: • You have an obligation to make your workplace safe. • Know and follow safety and health regulations affecting your job. • If you don’t know how, ask for training before you begin work. • Work safely, and encourage your co-workers to do the same. • Correct or immediately report any unsafe conditions to your supervisor. • Report any injury immediately to a First Aid attendant or supervisor. • Take the initiative; make suggestions for improved safety conditions. Site Orientation: • All new employees should have a site orientation from their supervisor and be given a brief on safety procedures including: the layout of the section, a safety orientation, fire exit locations and procedures, emergency equipment and location of first aid facilities or services. • Always be aware of your surroundings; • Look up for falling objects; • Be mindful of up/down traffic; • Be cautious of structural inadequacies; • Do not race up or down flights; • In a noisy environment, use visual cues to look for potential hazards. Only use designated walkways, they are there for a reason; and • Often some sites require workers to work in pairs or teams in case of an accident.

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Hazards: • Hazards in a work place can never be eliminated, but they can be controlled with proper equipment, training and supervision. • Hazards are divided into two general categories: – Physical hazards – those that can cause immediate damage to the body. Examples: Moving equipment, machinery, confined space; heat, cold, chemicals, electrical, visibility. – Delayed Injury hazards – those due to repeated exposure or, a delayed reaction of the human body causing injury. Examples: Noise, ergonomics, repetitive strain injury, back injury, inhalation, radiation. Computer Workstations: • Problems with lighting can cause eyestrain and may also contribute to muscle soreness and fatigue. • Avoid glare, position your computer workstation so that when you face the monitor, you are sitting beside or parallel to the window. • If you face the window, light from the outside shines directly into your eyes and makes it difficult for you to focus on the screen. • If you sit with your back to a window, you may have problems with reflections, or high light levels. In either situation, adjust the blinds to reduce the amount of light on your screen. • Overhead lights can shine directly in your eyes or reflect images onto your computer screen, making it difficult to view your screen. To avoid this adjust the angle of your screen so that it’s at right angles to the work surface. • The top line of text on your screen should be at eye level. Most of the screen will be slightly below eye level. • The distance between your eyes and the screen should be about arm’s length. • Your chair should provide good lumbar support. Lighting • Problems with lighting can cause eyestrain. • Poor lighting can also contribute to muscle soreness and fatigue. Back Injuries • Approximately 1/3 of workers will suffer back problems during their working life. Back injuries are the most common work related injury. • The low back is subject to greater mechanical stress than any other part of the body and, because of this, is commonly injured. • A majority of low-back problems are caused by simple strains that can heal within six to eight weeks with appropriate treatment. Fear and misunderstanding are the two main factors that can delay recovery. • For engineers and computer scientists, computer use can cause lower back pain and repetitive strain injuries over time.

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Everyone in a work force should wisely take a careful look at their work environment and their work habits. Both workers and management need to note whether their workplace is really safe. Both need to consider whether the job requires working with any toxic substances; and if so, are people adequately protected? Both managers and workers need to ask themselves whether they are constantly under stress. Does your environment accept work schedules that breach legally established limits or hours? Answers to questions such as these might reveal much about how safe people are at work. Creating a corporate culture of safety means being conscious of the dangers at work. Trying to maintain an unreasonable work schedule can be dangerous. Indeed, tired workers are less efficient and make more mistakes. Companies that foster excessive work and actively seek out and reward workaholics result into consequences that are potentially devastating. Poor work habits, which may include lack of tidiness and cleanliness, pose another hazard. Leaving tools thrown on the floor or live electric wires exposed often lead to accidents, even fatalities. The same can be said of ignoring safety precautions when using power tools and machinery. Another cause of injury and death is failing to clean up spilled fluids, especially toxic ones. Many injuries have occurred when workers have slipped on oily or wet floors. So it might be said that the first law of good work is to be clean and orderly. Yet, many are tempted to ignore safety procedures. Work pressure may lead to perceptions that short cuts are necessary to meet demands. Therefore, some may reason regarding a safety regulation, 'It has never caused any problem when I ignored it.' One of the worst things that you can do at work is ignore safety procedures and get away with it! Why? because this fosters overconfidence and carelessness, leading to more accidents. The explosion of the Chernobyl plant in Ukraine in 1986 is often described as "the world's worst nuclear accident." What went wrong? A report on the disaster speaks of a "catalogue of reckless operating procedures" and "the repeated flouting of safety precautions." Both employer and employee can cooperate in foreseeing potential safety hazards. Yes, the wise one observes what could prove to be a dangerous situation and looks for ways to protect himself and others. When employers do this, they benefit, and so do their employees. For example, a company that redesigned their office to avoid "sick building syndrome" found that before long, productivity was up and staff satisfaction levels had improved dramatically. It was also found that fewer people were out on sick leave. Such consideration for the health of others not only makes for a more pleasant atmosphere for employer and employee but, as seen in this case, can also make good sense economically. The proper approach to creating the safety culture is to make sure every employee applies a common-sense approach to safety. This includes being diligent in following local safety regulations. Doing this can go a long way towards making the workplace safer.

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1(c) Good Housekeeping 1(c)(1) General Information Housekeeping can reduce and eventually eliminate accident causes. The National Safety Council in the United States reports that falls due to improper housekeeping result in between 200,000 and 300,000 disabling industrial accidents each year. Management must take the initiative to properly train employees in the essentials of good housekeeping and in the necessity of maintaining a hazard-free workplace. Good housekeeping is one of the surest ways to identify a safe workplace. You can tell how workers' feel about safety just by looking at their housekeeping practices. Good housekeeping isn't the result of cleaning up once a week or even once a day. It's the result of keeping cleanedup all the time. It's an essential factor in a good safety program, promoting safety, health, production, and morale. Whose responsibility is housekeeping? It's everyone's. Clean work areas and aisles help eliminate tripping hazards. Respecting "wet floor" signs and immediately cleaning up spills prevents slipping injuries. Keeping storage areas uncluttered reduces the chances of disease and fire as well as slips, trips, and falls. Accumulated debris can cause fires, and clutter slows movement of personnel and equipment during fires. Other housekeeping practices include keeping tools and equipment clean and in good shape or keeping hoses and cables or wires bundled when not in use. Broken glass should be picked up immediately with a broom and dustpan, never with bare hands. Be aware of open cabinet drawers, electric wires, sharp corners or protruding nails. Either correct the unsafe condition if you are able and it is safe to do so, or notify the person responsible for overall maintenance that something should be done. How a workplace looks makes an impression on employees and visitors alike. A visitor's first impression of a business is important because that image affects the amount of business it does. Good housekeeping goes hand-in-hand with good public relations. It projects order, care, and pride. Besides preventing accidents and injuries, good housekeeping saves space, time, and materials. When a workplace is clean, orderly, and free of obstruction; work can get done safely and properly. Workers feel better, think better, do better work, and increase the quantity and quality of their work. 1(c)(2) Establishing a Good Housekeeping Program Effective housekeeping can eliminate some workplace hazards and help get a job done safely and properly. Poor housekeeping can frequently contribute to accidents by hiding hazards that cause injuries. If the sight of paper, debris, used and spent parts, fuses, clutter and spills is accepted as normal (Figure 1), then other more serious health and safety hazards may be taken for granted. Housekeeping is not just cleanliness. It includes keeping work areas neat and orderly; maintaining halls and floors free of slip and trip hazards; and removing of waste materials (e.g.,

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paper, cardboard) and other fire hazards from work areas. It also requires paying attention to important details such as the layout of the whole workplace, aisle marking, the adequacy of storage facilities, and maintenance. Good housekeeping is also a basic part of accident and fire prevention. Effective housekeeping is an ongoing operation: it is not a hit-and-miss cleanup done occasionally. Periodic "panic" cleanups are costly and ineffective in reducing accidents. Poor housekeeping can be a cause of accidents, such as: • • • • •

tripping over loose objects on floors, stairs and platforms; being hit by falling objects; slipping on greasy, wet or dirty surfaces; striking against projecting, poorly stacked items or misplaced material; and Figure 1. Example of poor housekeeping cutting, puncturing, or tearing the skin of hands or other parts of the body on projecting nails, wire or steel strapping.

To avoid these hazards, a workplace must "maintain" order throughout a workday. Although this effort requires a great deal of management and planning, the benefits are many. Effective housekeeping results in: • • • • • • • • • • •

reduced handling to ease the flow of materials; fewer tripping and slipping accidents in clutter-free and spill-free work areas; decreased fire hazards; lower worker exposures to hazardous substances; better control of tools and materials; more efficient equipment cleanup and maintenance; better hygienic conditions leading to improved health; more effective use of space; reduced property damage by improving preventive maintenance; less janitorial work; and improved morale.

A good housekeeping program plans and manages the orderly storage and movement of materials from point of entry to exit. It includes a material flow plan to ensure minimal handling. The plan also ensures that work areas are not used as storage areas by having workers move materials to and from work areas as needed. Part of the plan could include investing in extra bins and more frequent disposal.

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The costs of this investment could be offset by the elimination of repeated handling of the same material and more effective use of the workers' time. Often, ineffective or insufficient storage planning results in materials being handled and stored in hazardous ways (Figure 2). Knowing the plant layout and the movement of materials throughout the workplace can help plan work procedures. Worker training is an essential part of any good housekeeping program. Workers need to know how to work safely with the products Figure 2. Ineffective storage planning they use. They also need to know how to protect other workers such as by posting signs (e.g., "Wet - Slippery Floor") and reporting any unusual conditions. Housekeeping order is "maintained" not "achieved." This means removing the inevitable messes that occur from time to time and not waiting until the end of the shift to reorganize and clean up. Integrating housekeeping into jobs can help ensure this is done. A good housekeeping program identifies and assigns responsibilities for the following: • • • • •

clean up during the shift; day-to-day cleanup; waste disposal; removal of unused materials; and inspection to ensure cleanup is complete.

Do not forget out-of-the-way places such as shelves, basements, sheds, and boiler rooms that would otherwise be overlooked. The orderly arrangement of operations, tools, equipment and supplies is an important part of a good housekeeping program. The final addition to any housekeeping program is inspection. It is the only way to check for deficiencies in the program so that changes can be made. The documents on workplace inspection checklists provide a general guide and examples of checklists for inspecting offices and manufacturing facilities. The following elements constitute the basis for establishing a Good Housekeeping Program. 1(c)(2)(i) Dust and Dirt Removal In some jobs, enclosures and exhaust ventilation systems may fail to collect dust, dirt and chips adequately. Vacuum cleaners are suitable for removing light dust and dirt. Industrial models have special fittings for cleaning walls, ceilings, ledges, machinery, and other hard-to-reach places where dust and dirt may accumulate.

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Dampening floors or using sweeping compounds before sweeping reduces the amount of airborne dust. The dust and grime that collect in places like shelves, piping, conduits, light fixtures, reflectors, windows, cupboards and lockers may require manual cleaning. Specialpurpose vacuums are useful for removing hazardous substances. For example, vacuum cleaners fitted with HEPA (High Efficiency Particulate Air) filters may be used to capture fine particles of asbestos or fiberglass. Compressed air should not be used for removing dust, dirt or chips from equipment or work surfaces. First, compressed air is extremely forceful. Depending on its pressure, compressed air can dislodge particles. These particles are a danger since they can enter a worker’s eyes or abrade skin. The possible damage would depend on the size, weight, shape, composition, and speed of the particles. There have also been reports of hearing damage caused by the pressure of compressed air and by its sound. Second, compressed air itself is also a serious hazard. On rare occasions, some of the compressed air can enter the blood stream through a break in the skin or through a body opening. An air bubble in the blood stream is known medically as an embolism, a dangerous medical condition in which a blood vessel is blocked, in this case, by an air bubble. An embolism of an artery can cause coma, paralysis or death depending upon its size, duration and location. While air embolisms are usually associated with incorrect diving procedures, they are possible with compressed air due to high pressures. While this seems improbable, the consequences of even a small quantity of air or other gas in the blood can quickly be fatal. Horseplay has also been a cause of some serious workplace accidents caused by individuals not aware of the hazards of compressed air, or proper work procedures. 1(c)(2)(ii) Employee Facilities Employee facilities need to be adequate, clean and well maintained. Lockers are necessary for storing employees' personal belongings. Washroom facilities require cleaning once or more each shift. They also need to have a good supply of soap, towels, plus disinfectants, if needed. If workers are using hazardous materials, employee facilities should provide special precautions such as showers, washing facilities and changing rooms. Some facilities may require two locker rooms with showers between. Using such double locker rooms allows workers to shower off workplace contaminants and prevents them from contaminating their "street clothes" by keeping their work clothes separated from the clothing that they wear home. Smoking, eating or drinking in the work area should be prohibited where toxic materials are handled. The eating area should be separate from the work area and should be cleaned properly each shift. 1(c)(2)(iii) Surfaces Floors: Poor floor conditions are a leading cause of accidents so cleaning up spilled oil and other liquids at once is important. Allowing chips, shavings and dust to accumulate can also cause accidents. Trapping chips, shavings and dust before they reach the floor or cleaning them up regularly can prevent their accumulation. Areas that cannot be cleaned continuously, such as I-12

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entrance ways, should have anti-slip flooring. Keeping floors in good order also means replacing any worn, ripped, or damaged flooring that poses a tripping hazard. Walls: Light-colored walls reflect light while dirty or dark-colored walls absorb light. Contrasting colors warn of physical hazards and mark obstructions such as pillars. Paint can highlight railings, guards and other safety equipment, but should never be used as a substitute for guarding. The program should outline the regulations and standards for colors. 1(c)(2)(iv) Light Fixtures Dirty light fixtures reduce essential light levels. Clean light fixtures can improve lighting efficiency significantly. 1(c)(2)(v) Aisles and Stairways Aisles should be wide enough to accommodate people and vehicles comfortably and safely. Aisle space allows for the movement of people, products and materials. Warning signs and mirrors can improve sight-lines in blind corners. Arranging aisles properly encourages people to use them so that they do not take shortcuts through hazardous areas. Keeping aisles and stairways clear is important. They should not be used for temporary "overflow" or "bottleneck" storage. Stairways and aisles also require adequate lighting. 1(c)(2)(vi) Spill Control The best way to control spills is to stop them before they happen. Regularly cleaning and maintaining machines and equipment is one way. Another is to use drip pans and guards where possible spills might occur. When spills do occur, it is important to clean them up immediately. Absorbent materials are useful for wiping up greasy, oily or other liquid spills. Used absorbents must be disposed of properly and safely. 1(c)(2)(vii) Tools and Equipment Tool housekeeping is very important, whether in the tool room, on the rack, in the yard, or on the bench. Tools require suitable fixtures with marked locations to provide orderly arrangement, both in the tool room and near the work bench. Returning them promptly after use reduce the chances of being misplaced or lost. Workers should regularly inspect, clean and repair all tools and take any damaged or worn tools out of service. 1(c)(2)(viii) Maintenance The maintenance of buildings and equipment may be one of the most important elements of good housekeeping. Maintenance involves keeping buildings, equipment and machinery in safe, efficient working order and in good repair. This includes maintaining sanitary facilities and regularly painting and cleaning walls. Broken windows, damaged doors, defective plumbing and broken floor surfaces can make a workplace look neglected; these conditions can cause accidents and affect work practices. So, it is important to replace or fix broken or damaged items as quickly as possible. A good maintenance program provides for the inspection, maintenance, upkeep and repair of tools, equipment, machines and processes.

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1(c)(2)(ix) Waste Disposal The regular collection, grading and sorting of scrap contribute to good housekeeping practices. It also makes it possible to separate materials that can be recycled from those going to waste disposal facilities. Allowing material to build up on the floor wastes time and energy since additional time is required for cleaning it up. Placing scrap containers near where the waste is produced encourages orderly waste disposal and makes collection easier. All waste receptacles should be clearly labeled (e.g., recyclable glass, plastic, scrap metal, etc.). 1(c)(2)(x) Storage Good organization of stored materials is essential for overcoming material storage problems whether on a temporary or permanent basis. There will also be fewer strain injuries if the amount of handling is reduced, especially if less manual materials handling is required. The location of the stockpiles should not interfere with work but they should still be readily available when required. Stored materials should allow at least one meter (or about three feet) of clear space under sprinkler heads. Stacking cartons and drums on a firm foundation and cross tying them, where necessary, reduce the chance of their movement. Stored materials should not obstruct aisles, stairs, exits, fire equipment, emergency eyewash fountains, emergency showers, or first aid stations. All storage areas should be clearly marked. Flammable, combustible, toxic and other hazardous materials should be stored in approved containers in designated areas that are appropriate for the different hazards that they pose. Storage of materials should meet all requirements specified in the fire codes and the regulations of environmental and occupational health and safety agencies in your jurisdiction. 1(d) New Employee Orientation For employers with a safety manager, the manager can conduct the classroom part of orientation/training, prepare all the training materials (handouts, forms, checklists, lesson plan, etc.), conduct the employee evaluation, and maintain all documentation. The facility supervisor(s) can conduct the on-the-job training and observation, and determine when the employee is ready for the evaluation. For employers or departments without a safety manager, the company safety committee can share responsibilities for conducting the job hazard analyses and the training program. The safety committee can put together the orientation/training materials, conduct the "classroom" training, and keep records. The department where employees will work can conduct the hands-on training. During the orientation period, introduce new workers to all the basic safety information that applies to their work areas, such as:

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General hazards in the work area; Specific hazards involved in each task the employee performs; Hazards associated with other areas of the facility; Company safety policies and work rules; Proper safety practices and procedures to prevent accidents; The location of emergency equipment such as fire extinguishers, eyewash stations, firstaid supplies, etc.; Smoking regulations and designated smoking areas; Emergency evacuation procedures and routes; Who to talk to about safety questions, problems, etc.; What to do if there is an accident or injury; How to report emergencies, accidents, and near misses; How to select, use, and care for personal protective equipment; Safe housekeeping rules; Facility security procedures and systems; How to use tools and equipment safely; Safe lifting techniques and materials-handling procedures; and Safe methods for handling, using, or storing hazardous materials and the location of material safety data sheets.

Orientation programs can be updated and refined by reviewing accident near-miss reports. Nearmiss reports offered early warning signs of new or recurrent hazards in the workplace that must be corrected before someone gets hurt or equipment is damaged. An evaluation of illness and injury reports are also a catalyst for changes in safety orientation and training programs. Orientation can involve several levels of new employee involvement, from awareness information to formal training programs. Awareness orientation/training informs employees about a potential hazard in the workplace and their role in responding to the hazard, even though they are not directly exposed to the hazard. For example, "affected" employees can be told about locks and tags for electrical systems without being trained how to implement the lockout/tagout program. It is useful to rely on a checklist to ensure that appropriate safety orientation is provided to new workers. The following are two examples of a new employee safety orientation checklist. These checklists should be modified to fit the needs of the organization or site.

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1(e) Worker Rights The following Worker Rights are essentially adopted from the U.S. Occupational Safety and Health Act of 1970. You have the right to a safe workplace. NERC requires employers to provide a workplace that is free of serious recognized hazards and in compliance with NERC standards. Specifically, you have the right to: 1. Get training from your employer as required by NERC standards. a. Get training from your employer on chemicals you are exposed to during your work and information on how to protect yourself from harm. Employers must establish a comprehensive, written hazard communication program (chemical hazard communication). Your employer must label chemical containers, make material safety data sheets with detailed hazard information available to employees, and train you about the health effects of the chemicals you work with and what the employer is doing and what you can do to protect yourself from these hazards. b. The program must list the hazardous chemicals in each work area, how the employer will inform employees of the hazards of non-routine tasks (for example, the cleaning of reactor vessels), and hazards associated with chemicals in unlabeled pipes and how the employer will inform other employers at a multi-employer worksite of the hazards to which their employees may be exposed. c. Get training from your employer on a variety of other health and safety hazards and standards that your employer must follow. These include electrical safety, lockouttagout, blood-borne pathogens, confined spaces, construction hazards and a variety of other subjects. 2. Request information from your employer about NERC standards, worker injuries and illnesses, job hazards and workers' rights. a. Request information from your employer on safety and health hazards in your workplace, chemicals used in your workplace, tests your employer has done to measure chemical, noise and radiation levels, precautions you should take and procedures to be followed if you or other employees are involved in an incident or are exposed to hazardous chemicals or other toxic substances. b. Request copies of appropriate standards, rules, regulations and requirements that your employer should have available at the workplace. c. Review the log and summary of occupational injuries and illnesses at a reasonable time and in a reasonable manner or have an authorized representative do so for you. d. Access relevant exposure and medical records. e. Employers must inform you of the existence, location and availability of your medical and exposure records when you first begin employment and at least annually thereafter. Employers also must provide these records to you or your designated representatives within 15 working days of your request. When an employer plans to stop doing business and there is no successor employer to receive and maintain these records, the employer must notify you of your right of access to records at least 3 months before the employer ceases to do business. I-21

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f. Observe any monitoring or measuring of toxic materials or chemicals, as well as harmful physical agents, such as noise, and see the resulting records. If the exposure levels are above the NERC limit, the employer must tell you what will be done to reduce the exposure -- the right to observe monitoring exists only where monitoring is performed pursuant to a standard that provides employees with the right to observe. 3. Request action from your employer to correct hazards or violations. a. You may ask your employer to correct hazards even if they are not violations of specific NERC standards. Be sure to keep copies of any requests you make to your employer to correct hazards. b. File a complaint with NERC if you believe that there are either violations of NERC standards or serious workplace hazards. c. File a complaint and request NERC to conduct an inspection if you believe serious workplace hazards or violations of standards exist in your workplace. You can file a complaint online, in writing, by telephone or fax. If you want an NERC inspector to come inspect your workplace, put your complaint in writing and send it to the NERC. d. Request in your written complaint that NERC keep your name confidential if you do not want your employer to know who filed the complaint. 4. Be involved in NERC's inspection of your workplace. a. Have an authorized employee representative (such as a union representative) accompany the NERC compliance officer during the inspection tour. b. The authorized employee representative has a right to accompany a NERC compliance officer (also referred to as a compliance safety and health officer (CSHO) or inspector) during an inspection. Under no circumstances may the employer choose the workers' representative. c. Where there is no union or employee representative, the NERC inspector must talk confidentially with a reasonable number of workers during the course of the investigation. d. Respond to questions from the compliance officer and tell the compliance officer about workplace hazards, particularly if there is no authorized employee representative accompanying the compliance officer on the inspection "walkaround." e. You and your co-workers have a right to talk privately and confidentially to the compliance officer whether or not a workers' representative has been chosen. f. You may point out hazards, describe injuries or illnesses or near misses that resulted from those hazards and describe past complaints about hazards. Inform the inspector if working conditions are not normal during the inspection. Make sure that the inspector is aware if equipment has been shut down, windows opened or other conditions changed from normal. 5. Find out results of NERC inspections. a. Find out the results of NERC inspections and request a review if NERC decides not to issue a citation. b. If health hazards are present in your workplace, a special NERC health inspection may be conducted by an industrial hygienist. This NERC inspector may take samples to measure levels of chemicals or other hazardous materials.

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c. NERC will let the employee representative know whether your employer is in compliance. The inspector also will gather detailed information about your employer's efforts to control health hazards, including results of tests your employer may have conducted. 6. Get involved in any meetings or hearings to discuss any objections your employer has to NERC's citations or to changes in abatement deadlines. a. File a formal appeal of deadlines for correction of hazards. b. File an appeal of the deadlines that NERC sets for your employer to correct any violation in the citation issued to the employer. Write to NERC within 10 working days from the date the employer posts the notice requesting on extension of the abatement deadline if you feel the time is too long. 7. File a discrimination complaint. a. File a discrimination complaint with NERC within 30 days if you are punished or discriminated against for exercising your safety and health rights or for refusing to work when faced with an imminent danger of death or serious injury and there is insufficient time for NERC to inspect. 8. Request a research investigation on possible workplace health hazards. a. Contact NERC to request a health hazard evaluation if you are concerned about toxic effects of a substance in the workplace. 9. Provide comments and testimony to NERC during rulemaking on new standards.

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PART II. SAFETY AND BEST INDUSTRY PRACTICES SEC. 2(a) AIR QUALITY TESTING AND MONITORING ...............................................II-7 2(a)(1) Introduction ..................................................................................................................II-9 2(a)(2) Methods of Sampling and Testing...............................................................................II-9 2(a)(3) Samplers and Monitors ..............................................................................................II-10 2(a)(4) Batteries.......................................................................................................................II-19 2(a)(5) Adverse Conditions.....................................................................................................II-20 2(a)(6) Appendix - Instrument Chart....................................................................................II-21 2(a)(7) Bibliography................................................................................................................II-21 SEC. 2(b) NOISE TESTING AND MONITORING ...........................................................II-23 2(b)(1) Introduction ................................................................................................................II-25 2(b)(2) Noise Monitors and Meters .......................................................................................II-25 2(b)(3) Occupational Noise Exposure Standard ..................................................................II-27 2(b)(4) Bibliography................................................................................................................II-32 SEC. 2(c) RADIATION MONITORS AND METERS .......................................................II-35 2(c)(1) Introduction.................................................................................................................II-37 2(c)(2) Light .............................................................................................................................II-37 2(c)(3) Ionizing Radiation.......................................................................................................II-38 2(c)(4) Nonionizing Radiation................................................................................................II-38 2(c)(5) Survey Meters for Radiation Detection ....................................................................II-39 2(c)(6) Pocket Dosimeters.......................................................................................................II-41 2(c)(7) Audible Alarm Rate Meters and Digital Electronic Dosimeters ............................II-43 2(c)(8) Film Badges .................................................................................................................II-43 2(c)(9) Thermoluminescent Dosimeters ................................................................................II-44 2(c)(10) Annex – Guide to Meter Selection and Applications.............................................II-44 2(c)(11) Bibliography ..............................................................................................................II-46 SEC. 2(d) ELECTRICAL/ELECTRONICS TESTING METERS ...................................II-49 2(d)(1) Introduction ................................................................................................................II-51 2(d)(2) Electronic Test Equipment Types.............................................................................II-51 2(d)(3) General Information on Safe Use..............................................................................II-53 SEC. 2(e) SAFE CHEMICAL HANDLING.........................................................................II-55 2(e)(1) Introduction.................................................................................................................II-57 2(e)(2) Reference Standards...................................................................................................II-57 2(e)(3) Safe Chemical Exposure Tables ................................................................................II-90 SEC. 2(f) JOB HAZARDS ANALYSIS ASSESSMENT...................................................II-179 2(f)(1) Introduction ...............................................................................................................II-181 2(f)(2) Responsibility and Tailgate Meetings......................................................................II-181 2(f)(3) Hazards Assessment..................................................................................................II-182 2(f)(4) Hazard Assessment and PPE Checklists.................................................................II-191 II-1

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2(f)(5) Bibliography ..............................................................................................................II-200 SEC. 2(g) PERSONAL PROTECTIVE EQUIPMENT ....................................................II-201 2(g)(1) Introduction ..............................................................................................................II-203 2(g)(2) General Provisions....................................................................................................II-203 2(g)(3) Requirements of a PPE Program ............................................................................II-203 2(g)(4) Guidelines for PPE Selection ...................................................................................II-205 2(g)(5) Worker Training.......................................................................................................II-205 2(g)(6) Eye and Face Protection...........................................................................................II-206 2(g)(7) Head Protection ........................................................................................................II-208 2(g)(8) Foot and Leg Protection...........................................................................................II-209 2(g)(9) Hand and Arm Protection .......................................................................................II-210 2(g)(10) Protective Equipment for the Body ......................................................................II-214 2(g)(11) Hearing Protection .................................................................................................II-214 2(g)(12) Respiratory Protection ...........................................................................................II-215 2(g)(13) Bibliography............................................................................................................II-227 SEC. 2(h) FIRST AID AND RESUSCITATION ...............................................................II-229 2(h)(1) Introduction ..............................................................................................................II-231 2(h)(2) First Aid Assessments ..............................................................................................II-231 2(h)(3) Elements of a First Aid Training Program ............................................................II-232 2(h)(4) Periodic Program Updates ......................................................................................II-235 2(h)(5) First Aiders ...............................................................................................................II-235 2(h)(6) First Aid Training and Certification ......................................................................II-235 2(h)(7) First Aid for Electric Shock.....................................................................................II-236 2(h)(8) Skills Update .............................................................................................................II-237 2(h)(9) First Aid Supplies .....................................................................................................II-237 2(h)(10) Bibliography ...........................................................................................................II-238 SEC. 2(i) FIRE PROTECTION, EVACUATION, FIRST RESPONDER AND EMERGENCY PLANNING ...............................................................................II-239 2(i)(1) Flammability Properties ...........................................................................................II-241 2(i)(2) Ignition Temperature................................................................................................II-246 2(i)(3) Flammability Limits..................................................................................................II-247 2(i)(4) Vapor Density ............................................................................................................II-249 2(i)(5) Specific Gravity .........................................................................................................II-250 2(i)(6) Water Solubility.........................................................................................................II-250 2(i)(7) Responding to Fires...................................................................................................II-251 2(i)(8) Fire Fighting Agents..................................................................................................II-254 2(i)(9) Electrical Fire Prevention.........................................................................................II-258 2(i)(10) Firefighting Guidance .............................................................................................II-259 2(i)(11) Specialized Rescue Procedures...............................................................................II-264 2(i)(12) First Responder to Electrical Fire Incidents.........................................................II-265 2(i)(13) Evacuation Planning ...............................................................................................II-266 2(i)(14) Bibliography.............................................................................................................II-270

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SEC. 2(j) ELECTRIC SHOCK AND LOCKOUT/TAGOUT..........................................II-271 2(j)(1) Introduction ...............................................................................................................II-273 2(j)(2) Fuses ...........................................................................................................................II-273 2(j)(3) GFCIs .........................................................................................................................II-273 2(j)(4) Electrical Shock .........................................................................................................II-274 2(j)(5) Feedback Electrical Energy......................................................................................II-276 2(j)(6) Universal Precautions ...............................................................................................II-276 2(j)(7) Training Programs....................................................................................................II-276 2(j)(8) Protective Equipment and Work Practices ............................................................II-276 2(j)(9) Detection of Low Voltage..........................................................................................II-277 2(j)(10) Lockout/Tagout .......................................................................................................II-277 2(j)(11) Lockout Devices.......................................................................................................II-279 2(j)(12) Specific Procedures for Logout/Tagout.................................................................II-279 2(j)(13) Bibliography ............................................................................................................II-281 SEC. 2(k) HAND TOOLS AND WORKSHOP MACHINES...........................................II-283 2(k)(1) Introduction ..............................................................................................................II-285 2(k)(2) What Are the Hazards of Hand Tools? ..................................................................II-285 2(k)(3) What Are the Dangers of Power Tools?.................................................................II-286 2(k)(4) Guards .......................................................................................................................II-286 2(k)(5) Operating Controls and Switches ...........................................................................II-287 2(k)(6) Electric Tools ............................................................................................................II-287 2(k)(7) Portable Abrasive Wheel Tools...............................................................................II-288 2(k)(8) Pneumatic Tools .......................................................................................................II-289 2(k)(9) Liquid Fuel Tools......................................................................................................II-290 2(k)(10) Powder-Actuated Tools..........................................................................................II-290 2(k)(11) Hydraulic Power Tools ..........................................................................................II-291 2(k)(12) General Requirements of Safety in Workshops Policy.......................................II-292 2(k)(13) Machinery Installation...........................................................................................II-293 2(k)(14) Machine Controls ...................................................................................................II-293 2(k)(15) Machine Guards .....................................................................................................II-293 2(k)(16) Service Installations ...............................................................................................II-293 2(k)(17) Grinding and Polishing Machines.........................................................................II-294 2(k)(18) Milling Machines ....................................................................................................II-294 2(k)(19) Metal-Cutting Guillotines......................................................................................II-295 2(k)(20) General Considerations .........................................................................................II-295 2(k)(21) Solvent Degreasing .................................................................................................II-296 2(k)(22) Bibliography ...........................................................................................................II-296 SEC. 2(l) LINEMEN GENERAL SAFETY PRACTICES ...............................................II-297 2(l)(1) Introduction ...............................................................................................................II-299 2(l)(2) Scope ...........................................................................................................................II-299 2(l)(3) Shock Hazard Analysis .............................................................................................II-299 2(l)(4) Regulatory Issues.......................................................................................................II-300 2(l)(5) Standard Requirements ............................................................................................II-300 2(l)(6) Test Equipment Industry Recognized Good Practices .........................................II-300

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2(l)(7) Flash Hazard Analysis ..............................................................................................II-301 2(l)(8) Blast Hazard Analysis ...............................................................................................II-301 2(l)(9) Selection of Electrical Protective Equipment..........................................................II-302 2(l)(10) Exterior Safety Rules ..............................................................................................II-303 2(l)(11) Exterior Working Practices....................................................................................II-306 2(l)(12) Electrical Safety Rules ............................................................................................II-308 2(l)(13) Transformers and Circuit Breakers ......................................................................II-312 2(l)(14) Wire Markers...........................................................................................................II-313 2(l)(15) Adequacy and Effectiveness of the Training Program .......................................II-313 2(l)(16) Bibliography.............................................................................................................II-314 SEC. 2(m) ELECTRICAL SAFE WORK PRACTICES PLAN ......................................II-315 2(m)(1) Introduction .............................................................................................................II-317 2(m)(2) Training....................................................................................................................II-317 2(m)(3) Qualified Person ......................................................................................................II-317 2(m)(4) Safe Work Practices ................................................................................................II-317 SEC. 2(n) ELECTRICAL EQUIPMENT...........................................................................II-323 2(n)(1) Introduction ..............................................................................................................II-325 2(n)(2) Electrical Safety Facts..............................................................................................II-325 2(n)(3) Vehicular and Mechanical Equipment...................................................................II-326 2(n)(4) Use of Equipment .....................................................................................................II-327 2(n)(5) Test Equipment.........................................................................................................II-328 2(n)(6) Bibliography..............................................................................................................II-328 SEC. 2(o) LADDER SAFETY .............................................................................................II-329 2(o)(1) Introduction ..............................................................................................................II-331 2(o)(2) General Requirements .............................................................................................II-331 2(o)(3) Ladder Hazards/Prevention Tips ...........................................................................II-336 2(o)(4) Ladder Selection .......................................................................................................II-336 2(o)(5) Ladder Maintenance ................................................................................................II-336 2(o)(6) Ladder Inspections ...................................................................................................II-338 2(o)(7) Bibliography..............................................................................................................II-339 SEC. 2(p) FORKLIFT SAFETY .........................................................................................II-341 2(p)(1) Introduction ..............................................................................................................II-343 2(p)(2) Pre-Qualifications for Forklift Operators..............................................................II-343 2(p)(3) Safe Operating Procedures......................................................................................II-343 2(p)(4) Changing and Charging Storage Batteries ............................................................II-344 2(p)(5) Operations.................................................................................................................II-344 2(p)(6) Traveling ...................................................................................................................II-345 2(p)(7) Loading......................................................................................................................II-345 2(p)(8) Fueling .......................................................................................................................II-345 2(p)(9) Maintenance..............................................................................................................II-346 2(p)(10) Training...................................................................................................................II-346 2(p)(11) Refresher Training and Evaluation......................................................................II-347

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2(p)(12) Bibliography ...........................................................................................................II-348 SEC. 2(q) CRANE OPERATION SAFETY.......................................................................II-349 2(q)(1) Lifting Principles ......................................................................................................II-351 2(q)(2) Operational Considerations.....................................................................................II-352 2(q)(3) Construction Requirements.....................................................................................II-352 2(q)(4) Inspection Guidelines ...............................................................................................II-353 2(q)(5) Definitions .................................................................................................................II-366 2(q)(6) Bibliography..............................................................................................................II-368 SEC. 2(r) SCAFFOLDS AND OTHER WORK PLATFORMS ......................................II-369 2(r)(1) Introduction...............................................................................................................II-371 2(r)(2) Scaffold Safety...........................................................................................................II-371 2(r)(3) Bibliography ..............................................................................................................II-380 SEC. 2(s) SAFE WORK PRACTICES NEAR POWER LINES......................................II-381 2(s)(1) Introduction...............................................................................................................II-383 2(s)(2) Plan Ahead.................................................................................................................II-383 2(s)(3) Safe Work Practices..................................................................................................II-383 2(s)(4) Bibliography ..............................................................................................................II-388 SEC. 2(t) FUNCTIONAL SAFETY FOR ELECTRIC POWER TRANSMISSION.....II-391 2(t)(1) Introduction ...............................................................................................................II-393 2(t)(2) Structure of Electric Power Systems .......................................................................II-393 2(t)(3) Hazards in Electric Power Systems .........................................................................II-394 2(t)(3) Assuring Functional Safety ......................................................................................II-397 2(t)(4) Recommended References........................................................................................II-397 SEC. 2(u) EXCAVATIONS AND TRENCHING ..............................................................II-399 2(u)(1) Introduction ..............................................................................................................II-401 2(u)(2) Recommended Practices ..........................................................................................II-401 2(u)(3) Safety Guidelines ......................................................................................................II-403 2(u)(4) Excavation and Trenching Safety Program...........................................................II-404 2(u)(5) Requirements for Protective Systems.....................................................................II-415 2(u)(6) Definitions .................................................................................................................II-417 2(u)(7) Bibliography..............................................................................................................II-419 SEC. 2(v) CONFINED SPACES .........................................................................................II-421 2(v)(1) Identifying Confined Spaces ....................................................................................II-423 2(v)(2) Identifying Confined Space Hazards ......................................................................II-424 2(v)(3) Model Confined Space Entry Program ..................................................................II-426 2(v)(4) Personnel Responsibilities and Training ................................................................II-431 2(v)(5) Definitions..................................................................................................................II-434 2(v)(6) Bibliography..............................................................................................................II-436 APPENDIX A: Copy of Confined Space Entry Permit.....................................................II-437 APPENDIX B: Pre-Entry Planning Worksheet.................................................................II-440

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SEC. 2(w) COMPRESSED GAS CYLINDER SAFETY ..................................................II-443 2(w)(1) Introduction..............................................................................................................II-445 2(w)(2) Identification ............................................................................................................II-445 2(w)(3) Handling & Use........................................................................................................II-446 2(w)(4) Transportation of Cylinders ...................................................................................II-449 2(w)(5) Bibliography.............................................................................................................II-449 SEC. 2(x) DRUM HANDLING SAFETY...........................................................................II-451 2(x)(1) Introduction ..............................................................................................................II-453 2(x)(2) Types of Drums.........................................................................................................II-454 2(x)(3) Drum Inspection, Handling, and Staging Inspection ............................................II-455 2(x)(4) Leaking, Open, and Deteriorated Drums...............................................................II-456 2(x)(5) Preventing Back Injuries .........................................................................................II-458 SEC. 2(y) SAFE WELDING PRACTICES ........................................................................II-459 2(y)(1) Identifying Safe Welding Practices .........................................................................II-461 2(y)(2) Definitions..................................................................................................................II-461 2(y)(3) General Provisions....................................................................................................II-461 2(y)(4) Inspections.................................................................................................................II-464 2(y)(5) Ventilation Guidelines for Welding Operations ....................................................II-464

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SEC. 2(a) AIR QUALITY TESTING AND MONITORING CONTENTS 2(a)(1) Introduction ..................................................................................................................II-9 2(a)(2) Methods of Sampling and Testing...............................................................................II-9 2(a)(3) Samplers and Monitors ..............................................................................................II-10 2(a)(3)(i) Diffusive Samplers for Air Monitoring ................................................................. II-10 2(a)(3)(ii) Color Diffusion Tubes .......................................................................................... II-11 2(a)(3)(iii) Active Samplers................................................................................................... II-12 2(a)(3)(iv) Continuous Emissions Monitors .......................................................................... II-13 2(a)(3)(iv)(a) Photoionization Meters............................................................................... II-14 2(a)(3)(iv)(b) Infrared Analyzers...................................................................................... II-14 2(a)(3)(iv)(c) Toxic Gas Meters........................................................................................ II-15 2(a)(3)(iv)(d) Ozone Meter ............................................................................................... II-16 2(a)(3)(iv)(e) Mercury Analyzer-Gold Film Analyzer ..................................................... II-16 2(a)(3)(iv)(f) Direct-Reading Particle Monitors ............................................................... II-17 2(a)(3)(iv)(g) Combustible Gas Meters ............................................................................ II-18 2(a)(3)(iv)(h) Oxygen Meters ........................................................................................... II-19 2(a)(3)(iv)(i) Bioaerosol Monitors.................................................................................... II-19 2(a)(4) Batteries.......................................................................................................................II-19 2(a)(5) Adverse Conditions.....................................................................................................II-20 2(a)(6) Appendix - Instrument Chart....................................................................................II-21 2(a)(7) Bibliography................................................................................................................II-21

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2(a)(1) Introduction Indoor air quality testing may be necessary to ensure employee safety. Testing and monitoring may be applied to those conditions where employees may be exposed to: • • • • • • • • • • • •

nitrogen dioxide and sulfur dioxide landfill gases noxious odors radon gas factory emissions odor complaints rainwater metals smoke levels dust volatile organic compounds indoor air quality (including Carbon Monoxide)

The results of air quality testing may be used to: • •

Assign levels of worker respiratory protection For emergency planning

2(a)(2) Methods of Sampling and Testing Electric Power producers shall provide adequate means of carrying air monitoring in generator houses, transmitting stations, injection and switching substations, etc. to NERC specifications. Three main methods are available to measure air pollution: Passive Sampling: This refers to absorption or diffusion tubes or badges that provide a simple and inexpensive indication of average pollution levels over a period of weeks or months. Plastic tubes or discs, open at one end to the atmosphere and with a chemical absorbent at the other, collect a sample for subsequent analysis in the laboratory. The low cost per tube allows sampling at a number of points and is useful in highlighting "hotspots" where more detailed study may be needed. The quality and accuracy of the data from passive sampling tubes does not make them suitable for precise measurements but they can give useful long term trend data. Active Sampling: This involves the collection of samples, by physical or chemical means, for subsequent laboratory analysis. Typically, a known volume of air is pumped through a filter or chemical collector for a known period of time - the collection medium is then subjected to laboratory analysis. This method is not suitable for continuous or near-real time air quality monitoring. Automatic Sampling: This is the most sophisticated method of air quality analysis, producing high-resolution measurement data of a range of pollutants. The pollutants that can be measured include, but are not limited to, NOx, SO2 CO, O3, VOC's, PM10, PM2.5, Carbon Black, Hg, II-9

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Benzene etc. The air quality is continuously sampled and measured on-line and in real-time. The real time data is stored, typically as one hourly averages, with data being collected remotely from individual monitoring stations by telemetry. Remote control of the monitoring and data system is also possible as is remote diagnostics for most of the analyzers. 2(a)(3) Samplers and Monitors Toxic gas monitors are among the most reliable in the industry. Air quality testing is crucial to ensure a safe work environment. Samplers and monitors provided shall comply with NERC specifications. Rely on a comprehensive and continuous toxic gas monitor to comply with NERC regulations. 2(a)(3)(i) Diffusive Samplers for Air Monitoring This is a reliable, simple and inexpensive measurement technique. The sampling technique is based on molecular diffusion of gases, hence the term "diffusive sampling". The gas molecules diffuse into the sampler where they are quantitatively collected on an impregnated filter or an adsorbent material, giving a concentration value integrated over time. Since diffusive samplers are small, silent, have light weight and do not require electricity, their exposure site location can be relatively flexible. They can be used outdoors tropical conditions, in rural to urban environments, or indoors e.g. for personal exposure. No technically skilled personnel is required at the sampling site since the samplers are easy to handle and no field calibration is needed. See Figure 1.

Figure 1. Diffusive sampler1

After sampling, the analytes are chemically desorbed by solvent extraction or thermally desorbed and analyzed. Passive sampling does not involve the use of heavy and encumbering pumping systems, is not impacted by power disruptions, does not require extensive supervision, is quiet, 1

Photo downloaded from http://www.ivl.se/en/business/monitoring/diffusive_samplers.asp

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non-flammable and does not represent an explosion hazard. It can be performed by anyone, anywhere and at a very low cost. Moreover, it is not susceptible to sample breakthrough, a common problem associated with active sampling performed with an air pump. 2(a)(3)(ii) Color Diffusion Tubes Using the principles of gas diffusion and colorimetric reaction, Dräger Color Diffusion Tubes allow the user to reliably measure Time-Weighted Average (TWA) concentrations for up to eight hours. An easy-to-use tube holder allows safe tube end removal and secure sampling. Color Diffusion Tubes can be evaluated at any point during a workshift. The calibrated scale printed directly on each tube indicates parts-per-million-hours (ppm-hours). For a TWA reading, simply determine the point where the stain length ends and divide this reading by the total length of sampling time. No pumps, charts, or analyses are needed. To use a Diffusion Tube, place the tube in the tube holder with the red dot on the tube visible above the hinged portion of the holder (Figure 2a).

Figure 2a.

Open the tube by grasping the ends of the tube holder, with the red dot on the tube away from the body, and bending the holder until the tube breaks (Figure 2b)

Figure 2b

Remove the end of the tube from the holder and discard. The Diffusion Tube is ready for use. Snap the tube into the tube holder with the open end positioned at the open end of the holder (Figure 2c).

Figure 2c.

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Attach the diffusion tube holder to a worker's pocket or lapel and note the starting time of the test. At the end of the workshift, or any time during the workshift, the user can evaluate the tube. When using Diffusion Tubes, the Time-Weighted Average (TWA) can be calculated at any time during the measurement by simply dividing the length of the tube reading (in ppm-hours) by the elapsed sampling time (in hours). Table 1 provides guidance on the commercially available measurement ranges for Dräger Color Diffusion Tubes. Table 1. Ranges of Practical Measurement for Dräger Color Diffusion Tubes2

Chemical Hazard Acetic acid Ammonia Butadiene Carbon dioxide Carbon dioxide Carbon monoxide Ethanol Hydrochloric acid

Measuring Range (ppm-hrs) 1.3 – 200 2.5 – 1500 1.3 – 300 65 – 20000 0.13 - 30 vol% 6 – 600 125 - 25000 1.3 – 200

Chemical Hazard Hydrocyanic acid Hydrogen sulfide Nitrogen dioxide Perchloroethylene Sulfur dioxide Toluene Trichloroethylene

Measuring Range (ppm-hrs) 2.5 – 200 1.3 – 300 1.3 - 200 25 – 1500 0.7 – 150 13 – 3000 25 – 1000

2(a)(3)(iii) Active Samplers Active samplers are normally used to measure the average concentration of pollutants over periods of 30 minutes to 24 hours. For indoor air, the measurement can be undertaken with normal working conditions in the building, but if the purpose is to identify the presence of chemicals that may be a cause of odor or a health problem then ‘worst case’ conditions may be appropriate. This is best achieved by keeping all windows and doors closed in the room/s of interest for 12 hours before and during sampling. It may be appropriate to heat the room as normally if the problem is influenced by temperature. There are a range of active devices widely used to measure air pollutants. The Health and Safety Officer should first identify the nature of air pollutants that workers may be exposed to. For Volatile Organic Compounds (VOCs) - VOCs is a term used to cover a wide range of individual chemicals containing carbon that form a vapor in air. Most people are familiar with fumes from drying paint which fit into this category but many other products used in the workplace as well as consumer products (e.g. toiletries and polishes) are a source of VOCs. Outdoors pollution from traffic contains a wide range of VOCs including benzene. A number of VOCs are irritants and several can have specific health effects e.g. benzene is a carcinogen. As with all chemicals the health effect, if any, depends upon the concentration of the pollutant and the period that people are exposed. There is evidence that people’s sensitivity to pollutants varies considerably. 2

Data downloaded from http://www.skcinc.com/prod/800-01071.asp

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Commercially available sampling tubes are used to measure VOCs in the air. This is a stainless steel tube that contains a powdered adsorbent. When the end caps are removed and air pulled through the tube, VOCs are removed from the air by the sorbent. When returned to the laboratory, the tubes are analyzed by thermal desorption (TD) followed by gas chromatography with a flame ionization detector to measure amounts of VOCs collected and/or a mass spectrometer (MS) to confirm the identity of the individual VOCs collected. The adsorbent used determines the range of VOCs collected. A porous polymer (Tenax TA) has been widely used and this is optimum for compounds that have a boiling point between 75°C and 280°C. Sampling and analysis using this sorbent are in accordance with the International Standard ISO16000-6. Other sorbents are more suitable for compounds of different volatility, for example, some detectors use Carboxen 569 (a carbon molecular sieve) for the analysis of carbon disulphide. Polyurethane foam samplers are used for semi-volatile compounds (SVOCs), such as biocides and chemicals associated with oil mists. Formaldehyde and other volatile carbonyl compounds - Formaldehyde is an irritating gas released by many products and through combustion of fuels. It is useful as a preservative and is a component of glues used to bind particles of wood in particleboard and similar products. In outdoor air it occurs as a product of combustion and photochemical reaction. Other carbonyl compounds in air can include acetaldehyde, acetone, acrolein and glutaraldehyde. Special cartridge units can be used to measure carbonyls in the air. This is a circular plastic sampler that contains silica gel coated with a chemical that absorbs carbonyls from the air pulled through it by a pump. The sampling and analysis is undertaken in accordance with the International Standard ISO16000-3. Other pollutants – There are a range of continuous monitoring equipment to determine gases including nitrogen dioxide, carbon monoxide, methane, carbon dioxide and ozone in air. In addition, measurement of particulates (PM10) and ultrafine particles can be undertaken. The standards do not recommend or endorse any specific supplier or manufacturer. HSOs can identify specific suppliers and evaluate the most appropriate instruments based on cost, availability, dependability, reliability, and intended application. Active sampling normally requires a specialist to visit your site with a range of equipment to undertake the air sampling. Measurements of temperature and humidity are routinely made at the same time. Alternatively, the HSO can undertake the sampling alone; however close consultation with instrument suppliers is recommended. 2(a)(3)(iv) Continuous Emissions Monitors Continuous emissions monitors have been built using most types of sensor technology. There are systems in use using electrochemical, infrared, ultra-violet, chemiluminescent and other measurements for the toxic gases, whilst oxygen measurements are mainly carried out with II-13

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electrochemical, zirconium or paramagnetic sensors. All these methods have their own advantages and drawbacks, be it technological or financial. Among the portable instruments most suitable for workplace environments are combustible gas indicators (CGI) which detect flammables, four gas meters which detect flammables, oxygen, carbon monoxide and hydrogen sulfide, and photoionization (PID) detectors and the colorimetric tubes discussed above which detect low level toxics. None of these technologies is capable of identifying unknown gases and vapors. 2(a)(3)(iv)(a) Photoionization Meters Description and Applications. Ionization is based upon making a gas conductive by the creation of electrically charged atoms, molecules, or electrons and the collection of these charged particles under the influence of an applied electric field. The photoionization analyzer is a screening instrument used to measure a wide variety of organic and some inorganic compounds. It is also useful as a leak detector. The limit of detection for most contaminants is approximately 0.1 ppm. Calibration. The procedure for calibration involves applying the calibration gas (typically 100 ppm isobutylene) to the instrument and checking the reading. Special Considerations. The specificity of the instrument depends on the sensitivity of the detector to the substance being measured, the number of interfering compounds present, and the concentration of the substance being measured relative to any interference. Many models now have built-in correction or correlation factors. After calibrating the unit on isobutylene, select the gas to be measured. The instrument will automatically correct for the relative sensitivity of the gas selected. Some instruments are listed by an NRTL for hazardous locations. Check the operating manual for specific conditions. Maintenance. Keeping these instruments in top operating shape means charging the battery, cleaning the ultraviolet lamp window, light source and replacing the dust filter. The exterior of the instrument can be wiped clean with a damp cloth and mild detergent if necessary. Keep the cloth away from the sample inlet, however, and do not attempt to clean while the instrument is connected to line power. 2(a)(3)(iv)(b) Infrared Analyzers Description and Applications. The infrared analyzer is used as a screening tool for a number of gases and vapors and is presently the recommended screening method for substances with no feasible sampling and analytical method. These analyzers are often factory-programmed to measure many gases and are also userprogrammable to measure other gases. A microprocessor automatically controls the spectrometer, averages the measurement signal, and calculates absorbance values. Analysis results can be displayed either in parts per million (ppm)

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or absorbance units (AU). The variable path-length gas cell gives the analyzer the capability of measuring concentration levels from below 1 ppm up to percent levels. Some typical screening applications are: • • • •

Carbon monoxide and carbon dioxide, especially useful for indoor air assessments; Anesthetic gases including, e.g., nitrous oxide, halothane, enflurane, penthrane, and isoflurane; Ethylene oxide; and Fumigants including e.g. ethylene dibromide, chloropicrin, and methyl bromide.

Calibration. The analyzer and any strip-chart recorder should be calibrated before and after each use in accordance with the manufacturer's instructions. Special Considerations. The infrared analyzer may be only semispecific for sampling some gases and vapors because of interference by other chemicals with similar absorption wavelengths. Maintenance. No field maintenance of this device should be attempted except items specifically detailed in the instruction book such as filter replacements and battery charging. 2(a)(3)(iv)(c) Toxic Gas Meters Description and Application. This analyzer uses an electrochemical voltametric sensor or polarographic cell to provide continuous analyses and electronic recording. In operation, sample gas is drawn through the sensor and absorbed on an electrocatalytic sensing electrode, after passing through a diffusion medium. An electrochemical reaction generates an electric current directly proportional to the gas concentration. The sample concentration is displayed directly in parts per million. Since the method of analysis is not absolute, prior calibration against a known standard is required. Exhaustive tests have shown the method to be linear; thus, calibration at a single concentration, along with checking the zero point, is sufficient. Types: sulfur dioxide, hydrogen cyanide, hydrogen chloride, hydrazine, carbon monoxide, hydrogen sulfide, nitrogen oxides, chlorine, and ethylene oxide. Can be combined with combustible gas and oxygen meters. Calibration. Calibrate the direct-reading gas monitor before and after each use in accordance with the manufacturer's instructions and with the appropriate calibration gases. Special Considerations. • Interference from other gases can be a problem. See manufacturer’s literature. • When calibrating under external pressure, the pump must be disconnected from the sensor to avoid sensor damage. If the span gas is directly fed into the instrument from a regulated pressurized cylinder, the flow rate should be set to match the normal sampling rate. • Due to the high reaction rate of the gas in the sensor, substantially lower flow rates result in lower readings. This high reaction rate makes rapid fall time possible simply by II-15

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shutting off the pump. Calibration from a sample bag connected to the instrument is the preferred method. 2(a)(3)(iv)(d) Ozone Meter Description and Application. The detector uses a thin-film semiconductor sensor. A thin-film platinum heater is formed on one side of an alumina substrate. A thin-film platinum electrode is formed on the other side, and a thin-film semiconductor is formed over the platinum electrode by vapor deposition. The semiconductor film, when kept at a high temperature by the heater, will vary in resistance due to the absorption and decomposition of ozone. The change in resistance is converted to a change of voltage by the constant-current circuit. The measuring range of the instrument is 0.01 ppm to 9.5 ppm ozone in air. The readings are displayed on a liquid crystal display that reads ozone concentrations directly. The temperature range is 0°-40° C, and the relative humidity range is 10%-80% RH. Calibration. Calibrate instrument before and after each use. Be sure to use a well-ventilated area since ozone levels may exceed the PEL for short periods. Calibration requires a source of ozone. Controlled ozone concentrations are difficult to generate in the field, and this calibration is normally performed at SLTC. Gas that is either specially desiccated or humidified must not be used for preparing calibration standards, as readings will be inaccurate. Special Considerations. • The instrument is not intrinsically safe. • The instrument must not be exposed to water, rain, high humidity, high temperature, or extreme temperature fluctuation. • The instrument must not be used or stored in an atmosphere containing silicon compounds, or the sensor will be poisoned. • The instrument is not to be used for detecting gases other than ozone. Measurements must not be performed when the presence of organic solvents, reducing gases (such as nitrogen monoxide, etc.), or smoke is suspected; readings may be low. Maintenance. The intake-filter unit-Teflon sampling tube should be clean and connected firmly. These should be checked before each operation. Check pump aspiration and sensitivity before each operation. 2(a)(3)(iv)(e) Mercury Analyzer-Gold Film Analyzer Description and Application. This instrument relies on a gold-film analyzer that draws a precise volume of air over a gold-film sensor. A microprocessor computes the concentration of mercury in milligrams per cubic meter and displays the results on the digital meter. The meter is selective for mercury and eliminates interference from water vapor, sulfur dioxide, aromatic hydrocarbons, and particulates. However, hydrogen sulfide is an interferant. Calibration. Calibration should be performed by the manufacturer or a laboratory with the special facilities to generate known concentrations of mercury vapor. Instruments should be returned to the manufacturer or a calibration laboratory on a scheduled basis.

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Special Considerations. In high concentrations of mercury vapor the gold film saturates quickly. Check operating manual for more specific information. Maintenance. Mercury vapor instruments generally contain rechargeable battery packs, filter medium, pumps, and valves which require periodic maintenance. Except for routine charging of the battery pack, most periodic maintenance will be performed during the scheduled annual calibrations. However, depending on usage, routine maintenance should also include burning mercury deposits off of the gold-film and changing the zero filter when necessary. See operating manual for specific instructions. 2(a)(3)(iv)(f) Direct-Reading Particle Monitors Description and Applications. Condensation-nuclei counters are based upon a miniature, continuous-flow condensation nucleus counter (CNC) that takes particles too small to be easily detected, enlarges them to a detectable size, and counts them. Submicrometer particles are grown to supermicrometer alcohol droplets by first saturating the particles with alcohol vapor as they pass through a heated saturator lined with alcohol soaked felt, and then condensing the alcohol on the particles in a cooled condenser. Optics focus laser light into a sensing volume. As the droplets pass through the sensing volume, the particles scatter the light. The light is directed onto a photodiode which generates an electrical pulse from each droplet. The concentration of particles is counted by determining the number of pulses generated. Applications include the testing of respirators and dust monitors. The counter counts individual airborne particles from sources such as smoke, dust, and exhaust fumes. Models typically operate in one of three possible modes, each with a particular application. In the "count" mode, the counter measures the concentration of these airborne particles. In the "test" (or fit test) mode, measurements are taken inside and outside a respirator and a fit factor is calculated. In the "sequential" mode, the instrument measures the concentration on either side of a filter and calculates filter penetration. This instrument is sensitive to particles as small as 0.02 micrometers. However, it is insensitive to variations in size, shape, composition, and refractive index. Calibration. Check the counter before and after each use in accordance with the manufacturer's instructions. This usually involves checking the zero of the instrument. Special Considerations. Reagent-grade isopropyl alcohol for use in these types of instruments is available from HSO. •

• •

Dry the saturator felt by installing a freshly charged battery pack without adding alcohol. Allow the instrument to run until the LO message (low battery) or the E-E message (low particle count) appears. Some instruments allow you to remove the alcohol cartridge for storage purposes. Remove the battery pack. Install the tube plugs into the ends of the twin-tube assembly.

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Maintenance. Isopropyl alcohol must be added to the unit every 5-6 hours of operation, per the manufacturer's instructions. Take care not to overfill the unit. Under normal conditions, a fully charged battery pack will last for about 5 hours of operation. Low battery packs should be charged for at least 6 hours, and battery packs should not be stored in a discharged condition. 2(a)(3)(iv)(g) Combustible Gas Meters Description and Applications. These meters use elements which are made of various materials such as platinum or palladium as an oxidizing catalyst. The element is one leg of a Wheatstone bridge circuit. These meters measure gas concentration as a percentage of the lower explosive limit of the calibrated gas. The oxygen meter displays the concentration of oxygen in percent by volume measured with a galvanic cell. Other electrochemical sensors are available to measure carbon monoxide, hydrogen sulfide, and other toxic gases. Some units have an audible alarm that warns of low oxygen levels or malfunction. Calibration. Before using the monitor each day, calibrate the instrument to a known concentration of combustible gas (usually methane) equivalent to 25%-50% LEL full-scale concentration. The monitor must be calibrated to the altitude at which it will be used. Changes in total atmospheric pressure from changes in altitude will influence the instrument's measurement of the air's oxygen content. The unit's instruction manual provides additional details on calibration of sensors. Special Considerations. • Silicone compound vapors, leaded gasoline, and sulfur compounds will cause desensitization of the combustible sensor and produce erroneous (low) readings. • High relative humidity (90%-100%) causes hydroxylation, which reduces sensitivity and causes erratic behavior including inability to calibrate. • Oxygen deficiency or enrichment such as in steam or inert atmospheres will cause erroneous readings for combustible gases. • In drying ovens or unusually hot locations, solvent vapors with high boiling points may condense in the sampling lines and produce erroneous (low) readings. • High concentrations of chlorinated hydrocarbons such as trichloroethylene or acid gases such as sulfur dioxide will depress the meter reading in the presence of a high concentration of combustible gas. • High-molecular-weight alcohols can burn out the meters filaments. • If the flash point is greater than the ambient temperature, an erroneous (low) concentration will be indicated. If the closed vessel is then heated by welding or cutting, the vapors will increase and the atmosphere may become explosive. • For gases and vapors other than those for which a device was calibrated, users should consult the manufacturer's instructions and correction curves. Maintenance. The instrument requires no short-term maintenance other than regular calibration and recharging of batteries. Use a soft cloth to wipe dirt, oil, moisture, or foreign material from II-18

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the instrument. Check the bridge sensors periodically, at least every six months, for proper functioning. A thermal combustion-oxygen sensor uses electrochemical cells to measure combustible gases and oxygen. It is not widely used in the area offices. 2(a)(3)(iv)(h) Oxygen Meters These oxygen-measuring devices can include coulometric and fluorescence measurement, paramagnetic analysis, and polarographic methods. The output of most electrochemical oxygen sensors is dependent on the partial pressure of oxygen in the atmosphere. They do not actually measure concentration directly. An instrument calibrated at sea level and used at higher elevations, such as mountains, will indicate a value lower than the actual concentration. 2(a)(3)(iv)(i) Bioaerosol Monitors Description and Applications: A bioaerosol meter, usually a two-stage sampler, is also a multiorifice cascade impactor. This unit is used when size distribution is not required and only respirable-nonrespirable segregation or total counts are needed. Ninety-five to 100 percent of viable particles above 0.8 microns in an aerosol can be collected on a variety of bacteriological agar. Trypticase soy agar is normally used to collect bacteria, and malt extract agar is normally used to collect fungi. They can be used in assessing sick- (or tight-) building syndrome and mass psychogenic illness. These samplers are also capable of collecting virus particles. However, there is no convenient, practical method for cultivation and enumeration of these particles. Calibration: Bioaerosol meters must be calibrated before use. This can be done using an electronic calibration system with a high-flow cell, available through the HRT. Special Considerations: Prior to sampling, determine the type of collection media required and an analytical laboratory. The HRT can provide this information. This specialized equipment is available from the HRT with accompanying instructions. Maintenance: The sampler should be decontaminated prior to use by sterilizer or chemical decontamination with isopropanol. 2(a)(4) Batteries Many of the instruments described are powered by batteries. Battery care is important in assuring uninterruted sampling. A pump battery pack, for example, should be discharged to the recommended level before charging, at least after every use. If the pump is allowed to run down until the battery reaches the low battery Fault condition, the pump should be turned OFF soon after the Fault condition stops the pump. Leaving some pumps ON for a long time after this Fault condition can damage the battery pack. Also, avoid overcharging the battery pack. Alkaline Batteries. Replace frequently before they become depleted, or carry fresh replacements. When replacing a battery, never mix types (alkaline, carbon zinc, etc.) or capacity

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and age. Doing so can have negative affects on all the batteries. Remove batteries if equipment will not be used for an extended period of time. Rechargeable Ni-Cad Batteries. • Check the batteries under load (e.g., turn pump on and check voltage at charging jack, if one is available and this can be done safely) before use. See manufacturer's instructions for locations to check voltage. Use 1.2 volts per Ni-Cad cell for an estimate of the fully charged voltage of a rechargeable battery pack. • It is undesirable to discharge a multicell Ni-Cad battery pack to voltage levels that are below 1.0 volts per cell; doing this will drive a reverse current through some of the cells and can permanently damage them. • Rechargeable Ni-Cad batteries should be charged only in accordance with manufacturer's instructions. Chargers are generally designed to charge batteries in approximately 8 to 16 hours at a high charge rate. A battery can be overcharged and ruined when a high charge rate is applied for too long a time. However, Ni-Cad batteries may be left on a proper trickle charge indefinitely to maintain them at peak capacity. In this case, discharging for a period equal to the longest effective field service time may be necessary, because of short-term memory imprinting. However, do not let the battery run down overnight or longer. Turn the instrument OFF when the battery reaches the proper discharge level. Other Rechargeable Batteries: Other types of rechargeable batteries are being used in equipment such as lead-acid, nickel-metal hydride, etc. Make sure the manufacturer's instructions are followed concerning the handling and recharging of these types of batteries. 2(a)(5) Adverse Conditions Adverse Temperature Effects High ambient temperature, above 37.8°C and/or radiant heat (e.g., from nearby molten metal) can cause flow faults in air sampling pumps. If these conditions are likely, use the pump with a higher operating temperature range, as opposed to a pump with a lower operating temperature range. Temperature can also affect the accuracy of instrument readings or operation. Check the operating manual for the proper operating temperature range. Explosive Atmospheres • Instruments shall not be used in atmospheres where the potential for explosion exists unless the instrument is listed by a Nationally Recognized Testing Laboratory for use in the type of atmosphere present. Check the class and division ratings. • When batteries are being replaced, use only the type of battery specified on the safety approval label. • Do not assume that an instrument is intrinsically safe. Verify by contacting the instrument's maker if uncertain. Atmospheres Containing Carcinogens A plastic bag should be used to cover equipment when carcinogens are present. Decontamination procedures for special environments are available and are discussed in Part III and should be followed after using equipment in carcinogenic environments. If at all possible, decontaminate the equipment after use on-site. II-20

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2(a)(6) Appendix - Instrument Chart The information shown in Table 2 below is for reference only. Not every compliance officer or field office will have every type of instrument. Many of the instruments can be found in and are available through a Corporate Loan program. Table 2. Gas and Vapor Meters

Type of Instrument

Measured Substance

Application

Double-range meters

Combustible gas, O2

confined spaces

Triple range meters

Toxic, O2, combustible gas

confined spaces

Quad range meters

2 toxics, O2, combustible gas

CO dosimeter

CO

garages, indoor air quality

Carbon dioxide meter

CO2

indoor air quality (IAQ)

Infrared analyzers

CO, CO2, organic substances

traces indoor air, leaks, spills

Hydrogen cyanide monitors Hydrogen cyanide

plants

Hydrogen sulfide meters

Hydrogen sulfide

farms, sewers

Mercury vapor meters

Mercury

mercury plants, spills

NO and NO2 meters

NO and NO2 combustion

Ozone analyzers

O3

water or air purification, IAQ

2(a)(7) Bibliography A.M. Best Co. (AMB). 1990. Bests Safety Directory. AMB: Odwick, NJ. Hering, S.V., Ed. 1989. Air Sampling Instruments for Evaluation of Atmospheric Contaminants, American Conference of Governmental Industrial Hygienists: Cincinnati, Ohio. Cheremisinoff, N. P., 1999, Handbook of Industrial Toxicology and Hazardous Materials, Marcel Dekker Publishers, NY, NY.

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SEC. 2(b) NOISE TESTING AND MONITORING CONTENTS 2(b)(1) Introduction ................................................................................................................II-25 2(b)(2) Noise Monitors and Meters .......................................................................................II-25 2(b)(2) (i) Sound Level Meters .............................................................................................. II-25 2(b)(2) (ii) Personal Dosimeters ............................................................................................ II-26 2(b)(3) Occupational Noise Exposure Standard ..................................................................II-27 2(b)(3)(i) Allowable Levels of Exposure............................................................................... II-27 2(b)(3)(ii) Hearing Conservation Program ............................................................................ II-27 2(b)(3)(iii) Recordkeeping ..................................................................................................... II-31 2(b)(3)(iii)(a) Exposure Measurements ............................................................................ II-31 2(b)(3)(iii)(b) Audiometric Tests...................................................................................... II-31 2(b)(3)(iii)(c) Record Retention........................................................................................ II-31 2(b)(3)(iii)(d) Access to Records ...................................................................................... II-31 2(b)(3)(iii)(e) Transfer of Records.................................................................................... II-31 2(b)(4) Bibliography................................................................................................................II-32

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2(b)(1) Introduction Hearing protection should be issued to employees: • •

where extra protection is needed above what can been achieved using noise control; as a short-term measure while other methods of controlling noise are being developed.

The Health and Safety Officer (HSO) should not use hearing protection as an alternative to controlling noise by technical and organizational means. The National Electricity Health and Safety Standards require employers to: • • • • •

provide employees with hearing protectors if they ask for it and their noise exposure is between the lower and upper exposure action values; provide employees with hearing protectors and make sure they use them properly when their noise exposure exceeds the upper exposure action values; identify hearing protection zones, i.e. areas where the use of hearing protection is compulsory, and mark them with signs if possible; provide your employees with training and information on how to use and care for the hearing protectors; ensure that the hearing protectors are properly used and maintained.

Hearing protection can be used effectively by applying the following guidelines: • • • • •

make sure the protectors give enough protection - aim at least to get below 85 dB at the ear; target the use of protectors to the noisy tasks and jobs in a working day; select protectors which are suitable for the working environment - consider how comfortable and hygienic they are; think about how they will be worn with other protective equipment (e.g. hard hats, dust masks and eye protection); provide a range of protectors so that employees can choose ones which suit them.

Hearing protection can be used effectively by avoiding the following: • • •

provide protectors which cut out too much noise - this can cause isolation, or lead to an unwillingness to wear them; make the use of hearing protectors compulsory where the law doesn't require it; have a 'blanket' approach to hearing protection - better to target its use and only encourage people to wear it when they need to.

2(b)(2) Noise Monitors and Meters 2(b)(2)(i) Sound Level Meters Octave Band Analyzer. Some sound level meters may have an octave or one-third octave band filter attached or integrated into the instrument. The filters are used to analyze the frequency

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content of noise. They are also valuable for the calibration of audiometers and to determine the suitability of various types of noise control. Calibration. In normal operation, calibration of the instrument usually requires only checking. Prior to and immediately after taking measurements, it is a good practice to check, using a calibrator, the ability of the sound level instrument to correctly measure sound levels. As long as the sound level readout is within 0.2 dB of the known source, it is suggested that no adjustments to the calibration pot be made. If large fluctuations in the level occur (more than 1 dB) then either the calibrator or the instrument may have a problem. Special Considerations • Always check the batteries prior to use. Use the microphone windscreen to protect the microphone when the wearer will be outdoors or in dusty or dirty areas. (The windscreen will not protect the microphone from rain or extreme humidity.) • Never use any other type of covering over the microphone (e.g., plastic bag or plastic wrap) to protect it from moisture. These materials will distort the noise pickup, and the readings will be invalid. • Never try to clean a microphone, particularly with compressed air, since damage is likely to result. Although dirt and exposure will damage microphones, regular use of an acoustical calibrator will detect such damage so that the microphones can be replaced. • Remove the batteries from any meter that will be stored for more than 5 days. Protect meters from extreme heat and humidity. Maintenance. No field maintenance is required other than replacement of batteries. 2(b)(2)(ii) Personal Dosimeters Calibration. Field calibrate at the measurement site according to the manufacturer's instructions both before and after each use. Use an acoustical calibrator that was designed to be used with the particular model noise dosimeter being used. Special Considerations • Always check the batteries prior to use. Be very careful with the microphone cable. Never kink, stretch, pinch, or otherwise damage the cable. • Use the microphone windscreen to protect the microphone when the wearer will be outdoors or in dusty or dirty areas. (The windscreen will not protect the microphone from rain or extreme humidity.) • Never use any type of covering over the microphone (e.g., plastic bag or plastic wrap) to protect it from moisture. Such materials will distort the noise pickup, and the readings will be invalid. • Never try to clean a microphone, particularly with compressed air, since damage is likely to result. Although dirt and exposure to industrial environments will damage the microphones, regular use of an acoustical calibrator will detect such damage so that microphones can be replaced. • Remove the batteries when the dosimeter will be stored for more than 5 days. Protect dosimeters from extreme heat and humidity.

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Maintenance. No field maintenance is required other than replacement of batteries. 2(b)(3) Occupational Noise Exposure Standard 2(b)(3)(i) Allowable Levels of Exposure Protection against the effects of noise exposure shall be provided when the sound levels exceed those shown in Table 3 when measured on the A scale of a standard sound level meter at slow response. When noise levels are determined by octave band analysis, the equivalent A-weighted sound level may be determined as follows: Table 3. Permissible Noise Exposures(a),

Duration per day, hours 8 6 4 3 2 1.5 1 0.5 0.25 or less

Sound Level, dBA slow response 90 92 95 97 100 102 105 110 115

Footnote(a) When the daily noise exposure is composed of two or more periods of noise exposure of different levels, their combined effect should be considered, rather than the individual effect of each. If the sum of the following fractions: C(1)/T(1) + C(2)/T(2) C(n)/T(n) exceeds unity, then, the mixed exposure should be considered to exceed the limit value. Cn indicates the total time of exposure at a specified noise level, and Tn indicates the total time of exposure permitted at that level. Exposure to impulsive or impact noise should not exceed 140 dB peak sound pressure level.

When employees are subjected to sound exceeding those listed in Table 2, feasible administrative or engineering controls shall be utilized. If such controls fail to reduce sound levels within the levels of Table 3, personal protective equipment shall be provided and used to reduce sound levels within the levels of the table. If the variations in noise level involve maxima at intervals of 1 second or less, it is to be considered continuous. 2(b)(3)(ii) Hearing Conservation Program The employer shall administer a continuing, effective hearing conservation program, as described below, whenever employee noise exposures equal or exceed an 8-hour time-weighted average sound level (TWA) of 85 decibels measured on the A scale (slow response) or, equivalently, a dose of fifty percent. For purposes of the hearing conservation program, employee noise exposures shall be established without regard to any attenuation provided by the use of personal protective equipment. For purposes of establishing a program, an 8-hour time-weighted average of 85 decibels or a dose of fifty percent shall also be referred to as the action level. The following constitute the basic components of a hearing conservation program to be adopted and implemented:

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Monitoring: When information indicates that any employee's exposure may equal or exceed an 8-hour time-weighted average of 85 decibels, the employer shall develop and implement a monitoring program. Sampling: The sampling strategy shall be designed to identify employees for inclusion in the hearing conservation program and to enable the proper selection of hearing protectors. Where circumstances such as high worker mobility, significant variations in sound level, or a significant component of impulse noise make area monitoring generally inappropriate, the employer shall use representative personal sampling to comply with the monitoring requirements of the program unless the employer can show that area sampling produces equivalent results. All continuous, intermittent and impulsive sound levels from 80 decibels to 130 decibels shall be integrated into the noise measurements. Instruments used to measure employee noise exposure shall be calibrated to ensure measurement accuracy. Monitoring shall be repeated whenever a change in production, process, equipment or controls increases noise exposures to the extent that: Employee Notification: The employer shall notify each employee exposed at or above an 8hour time-weighted average of 85 decibels of the results of the monitoring. Observation of Monitoring: The employer shall provide affected employees or their representatives with an opportunity to observe any noise measurements conducted pursuant to this section. Audiometric Testing Program: The employer shall establish and maintain an audiometric testing program as provided in this paragraph by making audiometric testing available to all employees whose exposures equal or exceed an 8-hour time-weighted average of 85 decibels. The program shall be provided at no cost to employees. Audiometric tests should be performed by a licensed or certified audiologist, otolaryngologist, or other physician, or by a technician who has satisfactorily demonstrated competence in administering audiometric examinations, obtaining valid audiograms, and properly using, maintaining and checking calibration and proper functioning of the audiometers being used. A technician who performs audiometric tests must be responsible to an audiologist, otolaryngologist or physician. Baseline Audiogram: Within 6 months of an employee's first exposure at or above the action level, the employer shall establish a valid baseline audiogram against which subsequent audiograms can be compared.

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Testing to establish a baseline audiogram should be preceded by at least 14 hours without exposure to workplace noise. Hearing protectors may be used as a substitute for the requirement that baseline audiograms be preceded by 14 hours without exposure to workplace noise. The employer shall notify employees of the need to avoid high levels of non-occupational noise exposure during the 14-hour period immediately preceding the audiometric examination. Annual Audiogram: At least annually after obtaining the baseline audiogram, the employer shall obtain a new audiogram for each employee exposed at or above an 8-hour time-weighted average of 85 decibels. Evaluation of Audiogram: Each employee's annual audiogram shall be compared to that employee's baseline audiogram to determine if the audiogram is valid and if a standard threshold shift has occurred. This comparison may be done by a technician. If the annual audiogram shows that an employee has suffered a standard threshold shift, the employer may obtain a retest within 30 days and consider the results of the retest as the annual audiogram. The audiologist, otolaryngologist, or physician shall review problem audiograms and shall determine whether there is a need for further evaluation. The employer shall provide to the person performing this evaluation the following information: • • • •

A copy of the requirements for hearing conservation as set forth in this section; The baseline audiogram and most recent audiogram of the employee to be evaluated; Measurements of background sound pressure levels in the audiometric test room. Records of audiometer calibrations required by paragraph (h)(5) of this section.

Follow-up Procedures: If a comparison of the annual audiogram to the baseline audiogram indicates a standard threshold shift the employee shall be informed of this fact in writing, within 21 days of the determination. Unless a physician determines that the standard threshold shift is not work related or aggravated by occupational noise exposure, the employer shall ensure that the following steps are taken when a standard threshold shift occurs: • • •

Employees not using hearing protectors shall be fitted with hearing protectors, trained in their use and care, and required to use them. Employees already using hearing protectors shall be refitted and retrained in the use of hearing protectors and provided with hearing protectors offering greater attenuation if necessary. The employee shall be referred for a clinical audiological evaluation or an otological examination, as appropriate, if additional testing is necessary or if the employer suspects that a medical pathology of the ear is caused or aggravated by the wearing of hearing protectors.

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The employee is informed of the need for an otological examination if a medical pathology of the ear that is unrelated to the use of hearing protectors is suspected.

If subsequent audiometric testing of an employee whose exposure to noise is less than an 8-hour TWA of 90 decibels indicates that a standard threshold shift is not persistent, the employer: • •

Shall inform the employee of the new audiometric interpretation; and May discontinue the required use of hearing protectors for that employee.

Standard Threshold Shift: A standard threshold shift is a change in hearing threshold relative to the baseline audiogram of an average of 10 dB or more at 2000, 3000, and 4000 Hz in either ear. In determining whether a standard threshold shift has occurred, allowance may be made for the contribution of aging (presbycusis) to the change in hearing level by correcting the annual audiogram. Hearing Protectors: Employers shall make hearing protectors available to all employees exposed to an 8-hour time-weighted average of 85 decibels or greater at no cost to the employees. Hearing protectors shall be replaced as necessary. Employers shall ensure that hearing protectors are worn: • •

By an employee who is required to wear personal protective equipment; and By any employee who is exposed to an 8-hour time-weighted average of 85 decibels or greater, and who: – Has not yet had a baseline audiogram; or – Has experienced a standard threshold shift.

Employees shall be given the opportunity to select their hearing protectors from a variety of suitable hearing protectors provided by the employer. The employer shall provide training in the use and care of all hearing protectors provided to employees. The employer shall ensure proper initial fitting and supervise the correct use of all hearing protectors. Training Program: The employer shall institute a training program for all employees who are exposed to noise at or above an 8-hour time-weighted average of 85 decibels, and shall ensure employee participation in such program. The training program shall be repeated annually for each employee included in the hearing conservation program. Information provided in the training program shall be updated to be consistent with changes in protective equipment and work processes. The employer shall ensure that each employee is informed of the following:

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The effects of noise on hearing; The purpose of hearing protectors, the advantages, disadvantages, and attenuation of various types, and instructions on selection, fitting, use, and care; and The purpose of audiometric testing, and an explanation of the test procedures.

The employer shall make available to affected employees or their representatives copies of this standard and shall also post a copy in the workplace. 2(b)(3)(iii) Recordkeeping 2(b)(3)(iii)(a) Exposure Measurements The employer shall maintain an accurate record of all employee exposure measurements described in this section. 2(b)(3)(iii)(b) Audiometric Tests The employer shall retain all employee audiometric test records described in this section: This record shall include: • • • • • •

Name and job classification of the employee; Date of the audiogram; The examiner's name; Date of the last acoustic or exhaustive calibration of the audiometer; and Employee's most recent noise exposure assessment. The employer shall maintain accurate records of the measurements of the background sound pressure levels in audiometric test rooms.

2(b)(3)(iii)(c) Record Retention The employer shall retain records for at least the following periods: • •

Noise exposure measurement records shall be retained for two years. Audiometric test records shall be retained for the duration of the affected employee's employment.

2(b)(3)(iii)(d) Access to Records All records required by this section shall be provided upon request to employees, former employees, representatives designated by the individual employee, and the NERC. 2(b)(3)(iii)(e) Transfer of Records If the employer ceases to do business, the employer shall transfer to the successor employer all records required to be maintained by this section, and the successor employer shall retain them for the remainder of the period prescribed in this section.

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2(b)(4) Bibliography The following references were consulted. Internet sources can be accessed by typing the identified reference on a well-known search engine such as “Google”. OSHA Standards Recording and Reporting Occupational Injuries and Illnesses (29 CFR 1904) • 1904.10, Recording Criteria for Cases Involving Occupational Hearing Loss (for Recordkeeping) General Industry (29 CFR 1910) • 1910 Subpart G, Occupational health and environmental control – 1910.95, Occupational noise exposure Construction Industry (29 CFR 1926) • 1926 Subpart D, Occupational health and environmental controls – 1926.52, Occupational noise exposure • 1926 Subpart E, Personal protective and lifesaving equipment – 1926.101, Hearing protection Additional References (Internet Resources) • Acoustical Society of America • American Industrial Hygiene Association (AIHA) • American Speech-Language-Hearing Association • Guide for Selection and Use of Personal Protective Equipment & Special Clothing for Foundry Operators. OSHA and American Foundry Society (AFS) Safety and Health Committee (10Q), (2005), 914 KB PDF, 29 pages. This guide was developed by the American Foundry Society’s (AFS) Safety and Health Committee (10Q) and is a product of the OSHA and AFS Alliance. It describes special considerations for the selection and use of personal protective equipment and special clothing for work situations in metal melting and pouring operations that present a risk of exposure to foundry hazards. • E-A-R Hearing Conservation (and Hearing Loss Prevention) • Laborers’ Health & Safety Fund of North America (Topics of Interest: Noise) • National Hearing Conservation Association (NHCA) (see also OSHA's NHCA Alliance page) • National Institute of Occupational Safety and Health (NIOSH) (Hearing Loss Prevention) Printed Resources • Alberti, P.W. Personal Hearing Protection in Industry. New York: Raven Press, 1982. • Beranek, L.L. Noise and Vibration Control. New York: McGraw-Hill, 1971. • Berger, E. H., et al. The Noise Manual. 5th ed. Fairfax, VA: American Industrial Hygiene Association, 2000. • Cheremisinoff, N. P., Noise Control in Industry, Noyes Publications, Park Ridge, N.J. (1996). • Code of Federal Regulations. Title 29, Parts 1900 to 1990. Washington, DC: US Government Printing Office, 1992. • Harris, C.M. Handbook for Noise Control. 2nd ed. New York: McGraw-Hill, 1957. • Harris, C.M. Shock and Vibration Handbook. 3rd ed. New York: McGraw-Hill, 1988. II-32

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• • • • • • •

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Kryter, K.D. The Effects of Noise on Man. New York: Academic Press, 1970. Kryter, K.D. The Effects of Noise on Man. 2nd ed. New York: Academic Press, 1985. Olishifski, P.E. and E.R. Harford. Industrial Noise and Hearing Conservation. Chicago: National Safety Council, 1975. Field Operations Manual. OSHA Directive CPL 02-00-045 [CPL 2.45B]. Washington, DC: US Government Printing Office, 1992. Royster, Julia and Larry. Guide 15: A Guide to Developing and Maintaining an Effective Hearing Conservation Program. Raleigh, NC: North Carolina Department of Labor, Division of Occupational Safety and Health, 1998. Sataloff, J., and P. Michael. Hearing Conservation. Springfield, IL: Charles C Thomas, 1973. Sataloff, R.T., and J.T. Sataloff. Occupational Hearing Loss. New York: Marcel Dekker, 1987.

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SEC. 2(c) RADIATION MONITORS AND METERS CONTENTS 2(c)(1) Introduction.................................................................................................................II-37 2(c)(2) Light .............................................................................................................................II-37 2(c)(3) Ionizing Radiation.......................................................................................................II-38 2(c)(4) Nonionizing Radiation................................................................................................II-38 2(c)(5) Survey Meters for Radiation Detection ....................................................................II-39 2(c)(5)(i) Ion Chamber Counter............................................................................................. II-39 2(c)(5)(ii) Proportional Counter............................................................................................. II-40 2(c)(5)(iii) Geiger-Müller (GM) Counter .............................................................................. II-40 2(c)(5)(iv) Comparison of Gas Filled Detectors.................................................................... II-41 2(c)(6) Pocket Dosimeters.......................................................................................................II-41 2(c)(6)(i) Direct Read Pocket Dosimeter............................................................................... II-41 2(c)(6)(ii) Digital Electronic Dosimeter ................................................................................ II-42 2(c)(7) Audible Alarm Rate Meters and Digital Electronic Dosimeters ............................II-43 2(c)(8) Film Badges .................................................................................................................II-43 2(c)(9) Thermoluminescent Dosimeters ................................................................................II-44 2(c)(10) Annex – Guide to Meter Selection and Applications.............................................II-44 2(c)(11) Bibliography ..............................................................................................................II-46

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2(c)(1) Introduction Instruments used for radiation measurement fall into two broad categories: • •

rate measuring instruments and personal dose measuring instruments.

Rate measuring instruments measure the rate at which exposure is received (more commonly called the radiation intensity). Survey meters, audible alarms and area monitors fall into this category. These instruments present a radiation intensity reading relative to time, such as R/hr or mR/hr. An analogy can be made between these instruments and the speedometer of a car because both are measuring units relative to time. Dose measuring instruments are those that measure the total amount of exposure received during a measuring period. The dose measuring instruments, or dosimeters, that are commonly used in industrial radiography are small devices which are designed to be worn by an individual to measure the exposure received by the individual. An analogy can be made between these instruments and the odometer of a car because both are measuring accumulated units. The following provides general information on the selection and application of field instruments for monitoring radiation sources in the work place. 2(c)(2) Light Description and Applications. The light meter is a portable unit designed to measure visible, UV, and near-UV light in the workplace. The light meter is capable of reading any optical unit of energy or power level if the appropriate detector has been calibrated with the meter. The spectral range of the instrument is limited only by the choice of detector. Steady-state measurements can be made from a steady-state source using the "normal operation" mode. Average measurements can be obtained from a flickering or modulated light source with the meter set in the "fast function" position. Flash measurements can be measured using the "integrate" function. Calibration. No field calibration is available. These instruments are generally very stable and require only periodic calibration. Special Considerations. Exposure of the photomultiplier to bright illumination when the power is applied can damage the sensitive cathode or conduct excessive current. Maintenance. Little maintenance is required unless the unit is subjected to extreme conditions of corrosion or temperature. Clean the optical unit with lens paper to avoid scratching.

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2(c)(3) Ionizing Radiation Description and Applications. The ionizing radiation survey meter is useful for measuring radon decay products from air samples collected on filters. Wipe samples collected on a filter can also be counted with this detector, and general area sampling can be done. Several types of ionizing radiation meters are commercially available. The survey meter with the scintillation detector can be used to measure the presence of radondecay products in a dust sample. The barometric pressure should be noted for ionizing radiation chambers. Calibration. No field calibration is available. Periodic calibration by a laboratory is essential and should be handled by the manufacturer. 2(c)(4) Nonionizing Radiation Description and Applications. Various nonionizing radiation survey meters are available for measuring electromagnetic fields. The frequency ranges covered by instruments are: 10 Hz to 300 kHz, 0.5 MHz to 6000 MHz, 6 GHz to 40 GHz, and the 2.45 GHz microwave oven frequency. These instruments are capable of measuring the electric field strength (E-field), magnetic field strength (H-field), or both depending on the instrument. Depending on the instrument, electromagnetic field strengths from power lines, transformers, video display terminals, RF induction heaters, RF heat sealers, radio & television transmitters, microwave ovens and other sources can be measured. Calibration. No field calibration is available. Periodic calibration by the manufacturer is essential. Special Considerations. • Some of the instruments have an automatic instrument zeroing. Other instruments may require "zeroing" the instrument in a "zero-field" condition. Check the operating manual for guidance. • Some units have a peak memory-hold circuit that retains the highest reading in memory. • Some units operate with either electric (E) or magnetic (H) field probes based on diodedipole antenna design. Total field strength is measured at the meter regardless of the field orientation or probe receiving angle. The diode-dipole antenna design of the probe is much more resistant to burnout from overload than the thermocouple design of probes used with other meters. Maintenance. No field maintenance is required other than replacing the alkaline batteries when needed.

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2(c)(5) Survey Meters for Radiation Detection There are many different models of survey meters available to measure radiation in the field. They all basically consist of a detector and a readout display. Analog and digital displays are available. Most of the survey meters used for industrial radiography use a gas filled detector. Gas filled detectors consist of a gas filled cylinder with two electrodes. Sometimes, the cylinder itself acts as one electrode, and a needle or thin taut wire along the axis of the cylinder acts as the other electrode (Figure 3). A voltage is applied to the device so that the central needle or wire become an anode (+ charge) and the other electrode or cylinder wall becomes the cathode (charge). The gas becomes ionized whenever the counter is brought near radioactive substances. The electric field created by the potential difference between the anode and cathode causes the electrons of each ion pair to move to the anode while the positively charged gas atom is drawn to the cathode. This results in an electrical signal that is amplified, correlated to exposure and displayed as a value.

Figure 3. Gas Filled Detector

Depending on the voltage applied between the anode and the cathode, the detector may be considered an ion chamber, a proportional counter, or a Geiger-Müller (GM) detector. Each of these types of detectors have their advantages and disadvantages. A brief summary of each of these detectors is as follows. 2(c)(5)(i) Ion Chamber Counter Ion chambers have a relatively low voltage between the anode and cathode, which results in a collection of only the charges produced in the initial ionization event. This type of detector produces a weak output signal that corresponds to the number of ionization events. Higher energies and intensities of radiation will produce more ionization, which will result in a stronger output voltage. Collection of only primary ions provides information on true radiation exposure (energy and intensity). However, the meters require sensitive electronics to amplify the signal, which makes II-39

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them fairly expensive and delicate. The additional expense and required care is justified when it is necessary to make accurate radiation exposure measurements over a range of radiation energies. This might be necessary when measuring the Bremsstrahlung radiation produced by an X-ray generator. An ion chamber survey meter is sometimes used in the field when performing gamma radiography because it will provide accurate exposure measurements regardless of the radioactive isotope being used. 2(c)(5)(ii) Proportional Counter Proportional counter detectors use a slightly higher voltage between the anode and cathode. Due to the strong electrical field, the charges produced in the initial ionization are accelerated fast enough to ionize other electrons in the gas. The electrons produced in these secondary ion pairs, along with the primary electrons, continue to gain energy as they move towards the anode, and as they do, they produce more and more ionizations. The result is that each electron from a primary ion pair produces a cascade of ion pairs. This effect is known as gas multiplication or amplification. In this voltage regime, the number of particles liberated by secondary interactions is proportional to the number of ions produced by the passing ionizing particle. Hence, these gas ionization detectors are called proportional counters. Like ion chamber detectors, proportional detectors discriminate between types of radiation. However, they require very stable electronics which are expensive and fragile. Proportional detectors are usually only used in a laboratory setting. 2(c)(5)(iii) Geiger-Müller (GM) Counter Geiger-Müller counters operate under even higher voltages between the anode and the cathode, usually in the 800 to 1200 volt range. Like the proportional counter, the high voltage accelerates the charges produced in the initial ionization to where they have enough energy to ionize other electrons in the gas. However, this cascading of ion pairs occurs to a much larger degree and continues until the counter is saturated with ions. This all happens in a fraction of a second and results in an electrical current pulse of constant voltage. The collection of the large number of secondary ions in the GM region is known as an avalanche and produces a large voltage pulse. In other words, the size of the current pulse is independent of the size of the ionization event that produced it. The electronic circuit of a GM counters counts and records the number of pulses and the information is often displayed in counts per minute. If the instrument has a speaker, the pulses can also produce an audible click. When the volume of gas in the chamber is completely ionized, ion collection stops until the electrical pulse discharges. Again, this only takes a fraction of a second, but this process slightly limits the rate at which individual events can be detected. Because they can display individual ionizing events, GM counters are generally more sensitive to low levels of radiation than ion chamber instruments. By means of calibration, the count rate can be displayed as the exposure rate over a specified energy range. When used for gamma radiography, GM meters are typically calibrated for the energy of the gamma radiation being used. Most often, gamma radiation from Cs-137 at 0.662 MeV provides the calibration. Only small errors occur when the radiographer uses Ir-192 (average energy about 0.34 MeV) or Co-60 (average energy about 1.25 MeV).

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Since the Geiger-Müller counter produces many more electrons than an ion chamber counter or a proportional counter, it does not require the same level of electronic sophistication as other survey meters. This results in a meter that is relatively low cost and rugged. The disadvantages of GM survey meters are the lack of ability to account for different amounts of ionization caused by different energy photons and noncontinuous measurement (need to discharge). 2(c)(5)(iv) Comparison of Gas Filled Detectors In the ion chamber region, the voltage between the anode and cathode is relatively low and only primary ions are collected. In the proportional region, the voltage is higher, and primary ions and a number of secondary ions (proportional to the primary ions originally formed) are collected. In the GM region, a maximum number of secondary ions are collected when the gas around the anode is completely ionized. Note that discrimination between kinds of radiation (E1 and E2) is possible in the ion chamber and proportional regions. Radiation at different energy levels forms different numbers of primary ions in the detector. However in the GM region, the number of secondary ions collected per event remains the same no matter what the energy of the radiation that initiated the event. The GM counter gives up the ability to accurately measure the exposure due to different energies of radiation in exchange for a large signal pulse. This large signal pulse simplifies the electronics that are necessary for instruments such as survey meters. 2(c)(6) Pocket Dosimeters Pocket dosimeters are used to provide the wearer with an immediate reading of his or her exposure to x-rays and gamma rays. As the name implies, they are commonly worn in the pocket. The two types commonly used are the Direct Read Pocket Dosimeter and the Digital Electronic Dosimeter. 2(c)(6)(i) Direct Read Pocket Dosimeter A direct reading pocket ionization dosimeter is generally of the size and shape of a fountain pen (Figure 4). The dosimeter contains a small ionization chamber with a volume of approximately two milliliters. Inside the ionization chamber is a central wire anode, and attached to this wire anode is a metal coated quartz fiber. When the anode is charged to a positive potential, the charge is distributed between the wire anode and quartz fiber. Electrostatic repulsion deflects the quartz fiber, and the greater the charge, the greater the deflection of the quartz fiber. Radiation incident on the chamber produces ionization inside the active volume of the chamber. The electrons produced by ionization are attracted to, and collected by, the positively charged central anode. This collection of electrons reduces the net positive charge and allows the quartz fiber to return in the direction of the original position. The amount of movement is directly proportional to the amount of ionization which occurs.

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Figure 4. Direct Read Pocket Dosimeter

By pointing the instrument at a light source, the position of the fiber may be observed through a system of built-in lenses. The fiber is viewed on a translucent scale which is graduated in units of exposure. Typical industrial radiography pocket dosimeters have a full scale reading of 200 milliroentgens but there are designs that will record higher amounts. During the shift, the dosimeter reading should be checked frequently. The measured exposure should be recorded at the end of each shift. The principal advantage of a pocket dosimeter is its ability to provide the wearer an immediate reading of his or her radiation exposure. It also has the advantage of being reusable. The limited range, inability to provide a permanent record, and the potential for discharging and reading loss due to dropping or bumping are a few of the main disadvantages of a pocket dosimeter. The dosimeters must be recharged and recorded at the start of each working shift. Charge leakage, or drift, can also affect the reading of a dosimeter. Leakage should be no greater than 2 percent of full scale in a 24 hour period. 2(c)(6)(ii) Digital Electronic Dosimeter Another type of pocket dosimeter is the Digital Electronic Dosimeter. These dosimeters record dose information and dose rate. These dosimeters most often use Geiger-Müller counters. The output of the radiation detector is collected and, when a predetermined exposure has been reached, the collected charge is discharged to trigger an electronic counter. The counter then displays the accumulated exposure and dose rate in digital form. Some Digital Electronic Dosimeters include an audible alarm feature which emits an audible signal or chirp with each recorded increment of exposure. Some models can also be set to provide a continuous audible signal when a preset exposure has been reached. This format helps to minimize the reading errors associated with direct reading pocket ionization chamber dosimeters and allows the instrument to achieve a maximum readout before resetting is necessary.

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2(c)(7) Audible Alarm Rate Meters and Digital Electronic Dosimeters Audible alarms are devices that emit a short "beep" or "chirp" when a predetermined exposure has been received. It is required that these electronic devices be worn by an individual working with gamma emitters. These devices reduce the likelihood of accidental exposures in industrial radiography by alerting the radiographer to dosages of radiation above a preset amount. Typical alarm rate meters will begin sounding in areas of 450-500 mR/h. It is important to note that audible alarms are not intended to be and should not be used as replacements for survey meters. Most audible alarms use a Geiger-Müller detector. The output of the detector is collected, and when a predetermined exposure has been reached, this collected charge is discharged through a speaker. Hence, an audible "chirp" is emitted. Consequently, the frequency or chirp rate of the alarm is proportional to the radiation intensity. The chirp rate varies among different alarms from one chirp per milliroentgen to more than 100 chirps per milliroentgen 2(c)(8) Film Badges Personnel dosimetry film badges (Figure 5) are commonly used to measure and record radiation exposure due to gamma rays, X-rays and beta particles. The detector is, as the name implies, a piece of radiation sensitive film. The film is packaged in a light proof, vapor proof envelope preventing light, moisture or chemical vapors from affecting the film. A special film is used which is coated with two different emulsions. One side is coated with a large grain, fast emulsion that is sensitive to low levels of exposure. The other side of the film is coated with a fine grain, slow emulsion that is less sensitive to exposure. If the radiation exposure causes the fast emulsion in the processed film to be darkened to a degree that it cannot be interpreted, the fast emulsion is removed and the dose is computed using the slow emulsion. The film is contained inside a film holder or badge. The badge incorporates a series of filters to determine the quality of the radiation. Radiation of a given energy is attenuated to a different extent by various types of absorbers. Therefore, the same quantity of radiation incident on the badge will produce a Figure 5. Personnel Dosimerty different degree of darkening under each filter. By comparing these results, the energy of the radiation can be determined and Film Badge the dose can be calculated knowing the film response for that energy. The badge holder also contains an open window to determine radiation exposure due to beta particles. Beta particles are effectively shielded by a thin amount of material. The major advantages of a film badge as a personnel monitoring device are that it provides a permanent record, it is able to distinguish between different energies of photons, and it can measure doses due to different types of radiation. It is quite accurate for exposures greater than 100 millirem. The major disadvantages are that it must be developed and read by a processor (which is time consuming), prolonged heat exposure can affect the film, and exposures of less than 20 millirem of gamma radiation cannot be accurately measured. II-43

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Film badges need to be worn correctly so that the dose they receive accurately represents the dose the wearer receives. Whole body badges are worn on the body between the neck and the waist, often on the belt or a shirt pocket. The clip-on badge is worn most often when performing X-ray or gamma radiography. The film badge may also be worn when working around a low curie source. Ring badges are worn on a finger of the hand most likely to be exposed to ionizing radiation. A LIXI system with its culminated and directional beam would be one example where monitoring the hands would be more important than the whole body. 2(c)(9) Thermoluminescent Dosimeters Thermoluminescent dosimeters (TLD) are often used instead of the film badge. Like a film badge, it is worn for a period of time (usually 3 months or less) and then must be processed to determine the dose received, if any. Thermoluminescent dosimeters can measure doses as low as 1 millirem, but under routine conditions their low-dose capability is approximately the same as for film badges. TLDs have a precision of approximately 15% for low doses. This precision improves to approximately 3% for high doses. The advantages of a TLD over other personnel monitors are its linearity of response to dose, its relative energy independence, and its sensitivity to low doses. It is also reusable, which is an advantage over film badges. However, no permanent record or re-readability is provided and an immediate, on the job readout is not possible. A TLD is a phosphor, such as lithium fluoride (LiF) or calcium fluoride (CaF), in a solid crystal structure. When a TLD is exposed to ionizing radiation at ambient temperatures, the radiation interacts with the phosphor crystal and deposits all or part of the incident energy in that material. Some of the atoms in the material that absorb that energy become ionized, producing free electrons and areas lacking one or more electrons, called holes. Imperfections in the crystal lattice structure act as sites where free electrons can become trapped and locked into place. Heating the crystal causes the crystal lattice to vibrate, releasing the trapped electrons in the process. Released electrons return to the original ground state, releasing the captured energy from ionization as light, hence the name thermoluminescent. Released light is counted using photomultiplier tubes and the number of photons counted is proportional to the quantity of radiation striking the phosphor. Instead of reading the optical density (blackness) of a film, as is done with film badges, the amount of light released versus the heating of the individual pieces of thermoluminescent material is measured. The "glow curve" produced by this process is then related to the radiation exposure. The process can be repeated many times. 2(c)(10) Annex – Guide to Meter Selection and Applications Table 4 and Table 5 will help with the selection of appropriate meters through the comparison of their attributes and by their applications.

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Table 4. Radiation Detection Device Selection Chart

Attribute

GeigerMueller (GM) Tube

Proportional Counter

Semiconductor Detector

alpha • beta • x ray • gamma • neutron Gas

alpha • beta • x ray • gamma

to 500,000 c/m

to 100,000 c/m

1

3 mR/hr to 0.005 mR/hr 10,000 R/hr to 200 mR/hr or to 800,000 c/m 10-6 1

10-2

10-3

10-4

10-4

10-7

10-6

10-9

N/A

N/A

10

15

1

Low doserate surveys Area monitors Personnel radiation monitors Low-level contamination surveys Large output signal Moderate sensitivity

Medium and high dose-rate surveys Area monitors

Low-level contamination surveys LSC for tritium

Laboratory Low-level contamination Some field use surveys Neutron survey

Low energy dependence Simple to operate

High sensitivity Rapid response Good energy resolution

Rapid response

Excellent energy response Short dead time

Slow response Low sensitivity

Fragile Expensive

Requires stable highvoltage supply

Requires high amplification

Wide doserate range on a single

High sensitivity Rapid

Primary use is for alpha detection or

Primary use for alpha and gamma

alpha • beta • x ray • gamma

Sensitive Medium Ranges

Gas

Output Signal (V) Resolving Time (s) Energy Resolution (%) Use

0.04 mR/hr to 500 mR/hr

Disadvantages Long dead time Energy dependent Comments

Scintillation

alpha • beta alpha • beta • x ray • • x ray • gamma • gamma neutron Gas Solid • Liquid

Radiation Detected

Advantages

Ion Chamber

Radiation detected depends on

Solid

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Attribute

GeigerMueller (GM) Tube

the type of GM tube May be energy dependent Some models saturate—do not use in high radiation fields Sensitive to microwave fields Rate meter and audible pulse Rapid response Rugged, dependable

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Ion Chamber

instrument Low energy dependence Some models can be used in RF fields Some models slow to respond

Scintillation

response Fragile Audible signal and rate meter Radiation detected depends on instrument and crystal Fast neutron detector where dose rate is not required

Proportional Counter

Semiconductor Detector

neutron surveys Alpha detector can discriminate between alpha and beta-gamma Neutron detector can discriminate against gamma radiation Maintenance may be a problem

counting environmental samples May be used for in situ gamma fields

Table 5. Radiation Meter Application Chart.3

Type of instrument Heat stress meters Photoionization Light meters Nonionizing radiation meters Ionizing radiation meters Electrostatic field tester RF instruments

Measured substance Ambient (environmental) heat Ionizable substances Light Nonionizing radiation Ionizing radiation Static electric fields Electromagnetic fields

2(c)(11) Bibliography The following Internet references were consulted. www.iop.org/EJ/abstract/0022-3735/20/11/029/ 3

Source: http://hps.org/publicinformation/ate/faqs/devices.html

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Application foundries, furnaces, and ovens indoor air, leaks, spills indoor lighting, UV exposure communications, microwaves, heaters nuclear waste or plants hazardous locations RF heat sealers, VDT'S, induction motors

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www.iop.org/EJ/article/0022-3735/20/11/029/jev20i11p1426.pdf www.ki4u.com/nuclearsurvival/survival/detectors/index.htm www.regtron.kfkipark.hu/history.htm http://www.ndted.org/EducationResources/CommunityCollege/RadiationSafety/radiation_safety_equipment/rad iation_detectors.htm Radiation safety videos available on the Internet can be found at: http://www.ndted.org/EducationResources/CommunityCollege/RadiationSafety/Video/RTVideo.htm

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SEC. 2(d) ELECTRICAL/ELECTRONICS TESTING METERS CONTENTS 2(d)(1) Introduction ................................................................................................................II-51 2(d)(2) Electronic Test Equipment Types.............................................................................II-51 2(d)(2)(i) Basic Test Equipment ............................................................................................ II-51 2(d)(2)(ii) Probes ................................................................................................................... II-52 2(d)(2)(iii) Analyzers ............................................................................................................. II-52 2(d)(2)(iv) Signal-generating devices .................................................................................... II-52 2(d)(2)(iv) Miscellaneous Devices ........................................................................................ II-52 2(d)(3) General Information on Safe Use..............................................................................II-53

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2(d)(1) Introduction Electronic test equipment (called 'testgear') is used to create stimulus signals and capture responses from electronic Devices Under Tests (DUTs). In this way, the proper operation of the DUT can be proven or faults in the device can be traced and repaired. Use of electronic test equipment is essential to any serious work on electronics systems. Practical electronics engineering and assembly requires the use of many different kinds of electronic test equipment ranging from the very simple and inexpensive (such as a test light consisting of just a light bulb and a test lead) to extremely complex and sophisticated such as Automatic Test Equipment. Generally, more advanced test gear is necessary when developing circuits and systems than is needed when doing production testing or when troubleshooting existing production units in the field. The following is a general overview of the common test equipment that is available. 2(d)(2) Electronic Test Equipment Types 2(d)(2)(i) Basic Test Equipment The following items are used for basic measurement of voltages, currents, and components in the circuit under test. • • • •

Voltmeter (Measures voltage) Ohmmeter (Measures resistance) Ammeter, e.g. Galvanometer or Milliameter (Measures current) Multimeter e.g., VOM (Volt-Ohm-Milliameter) or DVM (Digital "Volt" Meter) (Measures all of the above)

The following are used for stimulus of the circuit under test: • • •

Power supplies Signal generator Pulse generator

The following analyze the response of the circuit under test: • •

Oscilloscope (Measures all of the above as they change over time) Frequency counter (Measures frequency)

Connecting it all together: •

Test probes

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Other commonly used meters are: • • • • • •

Solenoid voltmeter (Wiggy) Clamp meter (current transducer) Wheatstone bridge (Precisely measures resistance) Capacitance meter (Measures capacitance) EMF Meter (Measures Electric and Magnetic Fields) Electrometer (Measures charge)

2(d)(2)(ii) Probes These include: • • •

Multimeters RF probe Signal tracer

2(d)(2)(iii) Analyzers These include: • • • •

Logic analyzer (Tests digital circuits) Spectrum analyzer (SA) (Measures spectral energy of signals) Vector signal analyzer (VSA) (Like the SA but it can also perform many more useful digital demodulation functions) Time-domain reflectometer for testing integrity of long cables

2(d)(2)(iv) Signal-generating devices These include: • • • • •

Signal generator Frequency synthesiser Function generator Pulse generator Signal injector

2(d)(2)(iv) Miscellaneous Devices These include: • • • • • •

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Continuity tester Cable tester Hipot tester Network analyzer (used to characterize components or complete computer networks) Test light Transistor tester

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2(d)(3) General Information on Safe Use Description and Applications. Electrical testing meters include multimeters, clip-on current meters, megohmmeters, battery testers, ground-wire impedance testers, 120-V AC receptacle testers, ground fault interrupt testers, electrostatic meters, and AC voltage detectors. Multimeters measure AC or DC voltage or current and resistance. They can check for AC leakage, proper line voltage, batteries, continuity, ground connection, integrity of shielded connections, fuses, etc. Calibration. Few, if any, field calibrations are available. Check manufacturer's manual. Maintenance. No field maintenance is required other than battery-pack servicing

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SEC. 2(e) SAFE CHEMICAL HANDLING CONTENTS 2(e)(1) Introduction.................................................................................................................II-57 2(e)(1)(i) Permissions ............................................................................................................ II-57 2(e)(2) Reference Standards...................................................................................................II-57 2(e)(2)(i) Explanation of Material Safety Data Sheets (MSDS)............................................ II-57 2(e)(2)(ii) Occupational Safety and Health Administration .................................................. II-85 2(e)(2)(iii) National Institute for Occupational Safety and Health........................................ II-87 2(e)(2)(iv) American Conference of Governmental Industrial Hygienists............................ II-88 2(e)(2)(v) Agency for Toxic Substances and Disease Registry............................................. II-88 2(e)(2)(vi) World Health Organization.................................................................................. II-90 2(e)(3) Safe Chemical Exposure Tables ................................................................................II-90

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2(e)(1) Introduction Health and safety standards have been established throughout the world to protect the safety, health and welfare of people engaged in work or employment. These standards also protect coworkers, family members, employers, customers, nearby communities, and other members of the public that may be impacted by the workplace environment. In the United States, several federal agencies, including the Occupational Safety and Health Administration (OSHA), the National Institute for Occupational Safety and Health (NIOSH), the American Conference of Governmental Industrial Hygienists (ACGIH), the Agency for Toxic Substances and Disease Registry (ATSDR), the Environmental Protection Agency (EPA), and the World Health Organization (WHO), have developed and recommended health and safety standards. These standards are internationally recognized as a basis to provide safe levels of protection for workers. This subsection provides a summary of the standards as recommended by the above agencies. 2(e)(1)(i) Permissions The tables and information provided herein were compiled and previously published by Gulf Publishing Co. of Houston, Texas4. Permission for reprinting the tables and parts of text discussions in the NERC National Electricity Health and Safety Standards has been granted by the Authors and the Publisher for this Government of Nigeria publication. Information as presented may not be reproduced for sale or profit without the expressed permission of Gulf Publishing Co. and the Authors. 2(e)(2) Reference Standards 2(e)(2)(i) Explanation of Material Safety Data Sheets (MSDS) A Material Safety Data Sheet or MSDS is a multi-page document that contains information on the safe handling procedures and practices for chemical products. NERC requires employers to maintain a file of MSDS for all chemicals handled at a site, to train and educate workers on understanding how to use the information in an MSDS, and to make the file available and accessible to all employees. The MSDS for virtually any chemical product can be downloaded from multiple sources on the World Wide Web. The following is a detailed explanation of the types of information found on a typical MSDS. The information is usually organized into distinct sections which may include: I. II. III. IV. V. VI. VII. VIII.

Product Identification; Component Data; Precautions for Safe Handling and Storage; Physical Properties Data; Personal Protective Equipment; Fire and Explosion Hazard Information; Reactivity Information; First Aid;

4

Cheremisinoff, N. P., P. Rosenfeld, and A. Davletshin, Handbook of Environmental Management and Responsible Care, Gulf Publishing Co., Houston, TX, 2008

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IX. X. XI. XII. XIII. XIV. XV.

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Toxicology and Health Information; Transportation Information; Spill and Leak Procedures; Waste Disposal; Additional Regulatory Status Information; Additional Information; and Major References.

2(e)(2(1)(i) Product Identification The product name and product code are used to identify the product. The file number and revision number identify the Material Safety Data Sheet (MSDS) itself. The chemical family or name and synonyms are given with formula when applicable. A brief use description of the product is presented below along with the UN Hazard Classifications. 2(e)(2)(1)(ii) Component Data Most materials are evaluated to determine if they are hazardous. According to NERC, a hazardous chemical refers to any chemical that presents a physical hazard if it is combustible, flammable, pyrophoric, chemically unstable, water reactive or explosive, a compressed gas, an organic peroxide or other oxidizer. A chemical may present a health hazard if exposure could result in acute or chronic adverse health effects. If it has been determined that the product is a health hazard then all components that present a health hazard and that comprise 1% or more of the material are listed in this section. Also, any component that is a carcinogen is listed if it comprises 0.1% or more of the product. If it has been determined that the product is a physical hazard, then any component that presents a physical hazard is listed. Components in a product that the manufacturer believes are not hazardous are often referred to as inert ingredients. Normally, the chemical name and Chemical Abstracts Service (CAS) Numbers are used to identify a component. CAS numbers are assigned to chemicals and mixtures by the Chemical Abstracts Service (published by the American Chemical Society) as a specific identification, but they are generally recognized internationally. Where the identity of a component is a trade secret, a descriptive name is used instead of the chemical name and a trade secret access number is given to that component. Disclosure of the identity of the trade secret component will be made to health professional upon request, subject to the conditions specified in the Standard. Exposure limits are given for each component where these have been established. Definitions of these exposure limits are as follow: •

ACGIG TLV (Threshold Limit Value): A term used by the American Conference of Governmental Industrial Hygienists to express the airborne concentration of a material to which nearly all persons can be exposed day after day without adverse effects. ACGIH expresses TLVs in three ways: –

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TLV-TWA: The allowable Time-Weighted Average concentration for a normal 8-hour workday of a 40-hour workweek.

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–

TLV-STEL: The Short-Term Exposure Limit, or maximum concentration for a continuous 15-minute exposure period. A maximum of four such periods per day, with at least 60 minutes between exposure periods are allowed, provided that the daily TLV is not exceeded. – TLV-C: The Ceiling exposure limit; the concentration that should not be exceeded even instantaneously. – Skin: A notation used to indicate that the stated substance may be absorbed by the skin, mucous membranes and eyes, either by air or direct contact, and that this additional exposure must be considered part of the total exposure to avoid exceeding the TLV for that substance. The value quoted is the TWA unless another category is stated. •

OSHA PEL (Permissible Exposure limits): An exposure limit established by the Occupational Safety and Health Administration. May be a time-weighted average (TWA), short-term (STEL) or ceiling (C) exposure limit. A skin notation has the same meaning as for the TLV.

2(e)(2(1)(iii) Precautions for Safe Handling and Storage This section provides vital information for handling and storing a product. It is important that all recommendations be followed. 2(e)(2(1)(iv) Physical Data Knowledge of the physical properties of a substance is necessary for all safety and industrial hygiene decisions. Definitions of terms that apply to the physical data presented in this section are given below: • •

• •

Freezing Point/ Melting Point: The temperature at which a substance changes state from liquid to solid or solid to liquid. For mixtures, a range may be given. Boiling Point: The temperature at which a liquid changes to a vapor state at a given pressure. (Usually 760 mmHg, or one atmosphere). For mixtures, the initial boiling point or the boiling range may be given. Flammable materials with low boiling points generally present special fire hazards. Decomposition Temp: The temperature at which a substance will break down, or decompose, into smaller fragments. Specific Gravity: The weight of a material compared to the weight of an equal volume of water; an expression of the density (or heaviness) of the material. Example: if a volume of material weighs 3.6 kilograms, and an equal volume of water weighs 4.5 kilograms, the material has a specific gravity of 0.8: 3.6 kg/ 4.5 kg = 0.8 Insoluble materials with a specific gravity of less than 1.0 may float in (or on) water. Insoluble materials with a specific gravity greater than 1.0 may sink in water. Most

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insoluble flammable liquids having a specific gravity of less than 1.0 will float on water, an important consideration for fire suppression. Bulk Density: Weight of material per unit volume. pH: A value presenting the acidity or alkalinity of an aqueous solution. 1 ------------------------- 7 -------------------------14 Acidic Neutral Alkaline

• • •

•

• • •

Vapor Pressure: The pressure (usually expressed in millimeters of mercury) characteristic at any given temperature of a vapor in equilibrium with its liquid or solid form. Solubility in Water: The ability of a material to dissolve in water or another liquid. Solubility may be expressed as a ratio or may be described using words such as insoluble, very soluble or miscible. Evaporation Rate: The rate at which a particular material will vaporize (evaporate) when compared to the rate of vaporization of a known material. The evaporation rate can be useful in evaluating the health and fire hazards of a material. The known material is usually either normal butyl acetate or water, with a vaporization rate designated as 1.0. Odor Threshold: The odor threshold is the lowest concentration of a chemical in air that is detectable by smell. The ability to detect the odor of a chemical varies from person to person and depends on conditions such as the presence of other odorous materials. Odor cannot be used as a warning of unsafe conditions since workers may become used to the smell (adaptation), or the chemical may numb the sense of smell. Vapor Density (Air = 1): A relative comparison of the density of the vapor compared to the density of air (Air = 1). If the vapor density is greater than 1, then the vapor is heavier than air. Molecular Weight: The molecular weight of a chemical is the sum of the atomic weights of the atoms making up one molecule of the chemical. Coefficient of Oil/Water Distribution: If a substance which is soluble both in oil and in water is added to a two-phase oil/water system, then the ratio of the concentration of that substance in oil to its concentration in water is called the Coefficient of Oil/Water distribution.

2(e)(2)(1)(v) Personal Protective Equipment Requirements The proper use of personal protective equipment is of the utmost importance, and the guidelines presented in this section must be closely followed. Descriptions of specific equipment (goggles, gloves, respirators, etc.) required for routine use are given. Use of additional protective equipment, as required for fire-fighting and for spill and leak cleanup, is outlined in Section XI. Use of some products may require specific ventilation requirements. The following definitions apply to ventilation systems: •

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General Exhaust: A system for exhausting air containing contaminants from a general work area. General exhaust may be referred to as dilution ventilation.

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Local Exhaust: A system for capturing and exhausting contaminants from the air at the point where the contaminants are produced (welding, grinding, sanding, other processes or operations). Typical local exhausts include the fume hood, canopy hood, slot bench, dust collector and other devices engineered to remove contaminants from workers' breathing zones.

2(e)(2(1)(vi) Fire and Explosion Hazard Information Most of the terms that follow are defined in 29 CFR1910.1200(c) which should be consulted for the complete text. Note that some of these same terms have different definitions for transportation information. Shortened forms of the definitions are as follow: • • •

• • •

• •

Explosive: A chemical that causes an almost instantaneous release of gas and heat when subjected to certain conditions. Incompatible Materials: Materials that react with the product or with components of the product and may destroy the structure or function of a product; cause a fire, explosion or violent reaction; or cause the release of hazardous chemicals. Extinguishing Media: Agents which can put out fires involving the material. Common extinguishing agents are water, carbon dioxide, dry chemical, "alcohol" foam, and halogenated gases (Halons). It is important to know which extinguishers can be used so they can be made available at the worksite. Oxidizer: A material that gives up oxygen easily or can readily oxidize other materials. Examples of oxidizing agents are oxygen, chlorine and peroxide compounds. These chemicals will support a fire and are highly reactive Pyrophoric: A substance that burns spontaneously in air at a temperature of 54.4°C or below. Flammable: There are four classes of flammable chemicals as follows: – An aerosol flammable is an aerosol which yields a flame projection exceeding 45.7 centimeters or a flashback under certain test conditions. – A flammable gas is a gas which can ignite readily and burn rapidly or explosively. – A flammable liquid is any liquid having a flash point below 37.8°C, with the exception of mixtures in which 99% of the components have flash points of 37.8°C or higher. – A flammable solid is a solid (with certain exceptions ) that is liable to cause fire through friction, absorption of water or other reasons, or which can be ignited readily, and when ignited burns in such a manner as to create a serious hazard. Combustible: A combustible liquid is any liquid having a flash point at or above 37.8°C, but below 93.3°C, with the exception of mixtures in which 99% of the components have flash points of 93.3°C or higher. Flash Point: The temperature at which a liquid will give off enough flammable vapors to ignite in the presence of an ignition source.

There are several flash point test methods. Because flash points may vary for the same material depending on the method used, the method is indicated when the flash point is given. The methods most frequently quoted are:

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PMCC: Pensky-Martens Closed Cup – ASTM D93; SETA: Setaflash Closed Cup – ASTM D3278; and TCC: Tag (Tagliabue) Closed Cup – ASTM D56.

Details of these methods can be found in Section B of the Annual Book of ASTM Standards. • •

•

•

Autoignition Temperature: The lowest temperature at which a liquid will give off enough flammable vapors and heat energy to ignite spontaneously and maintain combustion. UEL and LEL: Upper Explosive Limit and Lower Explosive Limit (sometimes referred to as Upper and Lower Flammable Limits) are the highest concentration and lowest concentration respectively that will produce a flash of fire when an ignition source is present. At higher concentrations than the UEL, the mixture is too "rich" to burn. At concentrations lower than the LEL, the mixture is too "lean" to burn. NFPA Rating: The U.S. National Fire Protection Association Standard System for the Identification of the Fire Hazards of Materials (NFPA 704M). The NFPA ratings provide a general idea both of the hazards and of the degree of the hazards associated with a material relative to fire protection and control. The Standard addresses the hazards under the three categories of "Health", "Flammability" and "Reactivity" and assigns numeric ratings using a scale of 0 to 4 with 0 indicating no particular hazard, and 4 the most hazardous. It should be noted that health hazard ratings refer specifically to short-term exposure under fire conditions. The Standard also includes provisions for special hazard warnings, such as water reactivity. For further details see 'Fire Protection Guide on Hazardous Materials' – National Fire Protection Association, Quincy, MA. HMIS Ratings: The Hazard Materials Identification System of the U.S. National Paint and Coatings Association. The system is similar to the NFPA Standard in utilizing a 0-4 scale, rating the degree of hazard under the same three categories of health, flammability and reactivity, with 0 being the least hazardous and 4 the most. It should be noted that unlike NFPA ratings, HMIS ratings are not intended for emergency situations. The flammability and reactivity ratings will, however, usually be the same as the NFPA ratings. The health hazard rating is based on the acute toxicity of the chemical. For further information on these ratings, see 'HMIS Rating Manual' – National Paint and Coatings Association, Washington, DC.

2(e)(2(1)(vii) Reactivity Information A substance is said to be reactive if it readily enters into chemical reactions and undergoes chemical change. For MSDS purposes, the reactions can be grouped into three broad categories: •

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Decomposition - Stable/Unstable. A substance is stable if it is resistant to decomposition or possesses the ability to remain unchanged. For MSDS purposes, a material is stable if it remains in the same form under expected and reasonable conditions of use. A substance is considered unstable if it tends to suffer decomposition under these conditions. Some materials may become unstable at higher temperatures. Whenever relevant, the temperature at which a material can be said to be unstable is stated. Other conditions that may cause instability, such as shock from dropping or static electricity, are noted when applicable.

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Polymerization - Hazardous Polymerization. A polymerization reaction is hazardous when it takes place at a rate that releases large amounts of energy. If hazardous polymerization can occur with a given material, the MSDS usually will list conditions that could start the reaction. In addition, since the material usually contains a polymerization inhibitor, the expected time period before the inhibitor is used up is also given. Reactions with Other Chemicals - Incompatible Materials. Materials that could cause dangerous reactions from direct contact with one another are described as incompatible. Common chemicals that react with the product are usually listed in the MSDS. Hazardous products of decomposition, including combustion products, are listed.

2(e)(2(1)(viii) First Aid First aid procedures are described for each of the normal routes of exposure. It is important that first aid be administered as soon as possible after exposure has occurred. If in any doubt regarding the victim's condition, a physician should be called. 2(e)(2(1)(ix) Toxicology and Health Information The consequences of exposure, if any, by inhalation, skin or eye contact, or ingestion are outlined in this section. The signs, symptoms and effects that the exposure could produce are described so that any exposure would be recognized as quickly as possible and the appropriate action taken. The organs that are more susceptible to attack are referred to as target organs. The effects and damage that exposure could produce on these organs are given together with the symptoms. Some of the terms used that may be less familiar or which may have a specific inference in MSDS are defined below: • • • • •

• • •

Acute Effect: An adverse effect on a human or animal resulting from a single exposure with symptoms developing almost immediately after exposure. The effect is often of short duration. Chronic Effect: An adverse effect on a human or animal body resulting from repeated low level exposure, with symptoms that develop slowly over a long period of time or that reoccur frequently. Corrosive: A liquid or solid that causes visible destruction or irreversible alterations in human or animal tissue. Irritation: An inflammatory response or reaction of the eye, skin or respiratory system. Allergic Sensitization: A process whereby on first exposure a substance causes little or no reaction in humans or test animals, but which on repeated exposure may cause a marked response not necessarily limited to the contact site. Skin sensitization is the most common form of sensitization in the industrial setting, although respiratory sensitization is also known to occur. Teratogen: A substance or agent to which exposure of a pregnant female can result in malformations (birth defects) to the skeleton and or soft tissue of the fetus. Mutagen: A substance or agent capable of altering the genetic material in a living organism. Carcinogen: A substance or agent capable of causing or producing cancer in humans or animals. Authorities/organizations that have evaluated whether or not a substance is a II-63

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carcinogen are the International Agency for Research on Cancer (IARC), the U.S. National Toxicology Program (NTP) and OSHA. Target Organ Effects: Chemically-caused effects upon organs and systems such as the liver, kidneys, nervous system, lungs, skin, and eyes from exposure to a material.

To evaluate the potential human effects from exposure to hazardous chemicals, studies on laboratory animals are performed. The terms most commonly used to define the results of the studies are as follows: •

•

LD50 (Lethal Dose Fifty) - The dose of a substance expected to cause the death of 50% of an experimental animal population. This dose may be from oral, dermal or other routes of exposure. The units given for the LD50 are usually milligrams per kilogram body weight of the tested animal (mg/kg). LC50 (Lethal Concentration Fifty) - A calculated concentration of a substance in air, exposure to which for specified length of time is expected to cause the death of 50% of a laboratory animal population. This concentration is usually in units of milligrams per cubic meter of air (mg/m3) or milligrams per liter of air (mg/1) and is given for some time period (usually one or four hours).

Other terms occasionally used are: • • •

LDLO (Lethal Dose Low) - The lowest dose of substance introduced by any route other than inhalation reported to have caused death in humans or animals. LCLO (Lethal Concentration Low) - The lowest concentration of a substance in air that has been reported to have caused death in humans or animals. TDLO (Toxic Dose Low) - The lowest dose of a substance to which humans or animals have been exposed and reported to produce a toxic effect other than cancer.

2(e)(2(1)(x) Transportation Information In the United States, chemical materials are regulated as hazardous by the U.S. Department of Transportation (DOT) and are described in the Hazardous Materials Regulations in the Code of Federal Regulations, 49 Chapter 1 subchapter C are outlined in the LAND portion of Section X. Nigeria has nothing comparable at the moment, but may refer to the International Maritime Organization (IMO) and IATA/ICAO regulations as a reference. 2(e)(2(1)(xi) Spill and Leak Procedures Procedural recommendations relative to air, land and water are described. During cleanup of spills or leaks, it may be necessary to use extra personal protective equipment as compared to normal operations. 2(e)(2(1)(xii) Waste Disposal This section gives guidelines for disposing of a product if it becomes a waste. Recommendations are based upon the physical state and hazardous properties of the material. If the material is designated as hazardous it must be disposed of in a permitted hazardous waste treatment, storage, or disposal facility in accordance with local, state, and federal regulations. If the material is nonII-64

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hazardous, recommendations for disposal are made depending on the physical state and known characteristics of the material. 2(e)(2(1)(xiii) Additional Regulatory Information This section contains information relevant to compliance with laws. 2(e)(2(1)(xiv) Additional Information Any relevant additional information is given in this section. 2(e)(2(1)(xv) Major References This section lists some of the major references that have been consulted in preparing the Material Safety Data Sheet. 2(e)(2(1)(xv) Definition of Terms This subsection defines common terms found on MSDSs for the reader. The terms are listed alphabetically. If the term you are looking for is not described, other good sources of information are a chemical dictionary or a regular dictionary. Due to the large number of medical terms which might be used on an MSDS, medical terms are NOT explained here. Advice about the meaning of medical terms can be obtained from someone fully familiar with their use, such as an occupational physician or nurse. ACGIH - ACGIH stands for American Conference of Governmental Industrial Hygienists. The ACGIH is an association of occupational health professionals employed by government and educational institutions. The Threshold Limit Value (TLV) Committee and Ventilation Committee of the ACGIH publish guidelines which are used worldwide. Acid, Acidic - See pH. Active Ingredient - An active ingredient is the part of a product which actually does what the product is designed to do. It is not necessarily the largest or most hazardous part of the product. For example, an insecticidal spray may contain less than 1% pyrethrin, the ingredient which actually kills insects. The remaining ingredients are often called inert ingredients. Acute - Acute means sudden or brief. Acute can be used to describe either an exposure or a health effect. An acute exposure is a short-term exposure. Short-term means lasting for minutes, hours or days. An acute health effect is an effect that develops either immediately or a short time after an exposure. Acute health effects may appear minutes, hours or even days after an exposure. (See also Chronic). Aerosol - An aerosol is a collection of very small particles suspended in air. The particles can be liquid (mist) or solid (dust or fume). The term aerosol is also commonly used for a pressurized container (aerosol can) which is designed to release a fine spray of a material such as paint. Inhalation of aerosols is a common route of exposure to many chemicals. Also, aerosols may be fire hazards.

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AIHA - AIHA stands for American Industrial Hygiene Association. Alkali, Alkaline - See pH. ANSI - ANSI stands for the American National Standards Institute. Auto-Ignition Temperature - The auto-ignition temperature is the lowest temperature at which a material begins to burn in air in the absence of a spark or flame. Many chemicals will decompose (break down) when heated. The autoignition temperature is the temperature at which the chemicals formed by decomposition begin to burn. Auto-ignition temperatures for a specific material can vary by one hundred degrees Celsius or more, depending on the test method used. Therefore, values listed on the MSDS may be rough estimates. To avoid the risk of fire or explosion, materials must be stored and handled at temperatures well below the auto-ignition temperature. Base, Basic - See pH. Biohazardous Infectious Material - Under the Canadian Controlled Products Regulations, a biohazardous infectious material is a material that contains organisms which can cause disease in humans or animals. For example, a person exposed to a blood sample from someone with hepatitis B may contract the disease. Some jurisdictions require MSDSs for products which contain biohazardous infectious materials. BOD - BOD stands for biological oxygen demand. Boiling Point - The boiling point is the temperature at which the material changes from a liquid to a gas. Below the boiling point, the liquid can evaporate to form a vapor. As the material approaches the boiling point, the change from liquid to vapor is rapid and vapour concentrations in the air can be extremely high. Airborne gases and vapors may pose fire, explosion and health hazards. Sometimes, the boiling point of a mixture is given as a range of temperatures. This is because the different ingredients in a mixture can boil at different temperatures. If the material decomposes (breaks down) without boiling, the temperature at which it decomposes may be given with the abbreviation "dec." Some of the decomposition chemicals may be hazardous. (See also Thermal Decomposition Products). Carcinogen, Carcinogenic, Carcinogenicity - A carcinogen is a substance which can cause cancer. Carcinogenic means able to cause cancer. Carcinogenicity is the ability of a substance to cause cancer. Under the Canadian Controlled Products Regulations, materials are identified as carcinogens if they are recognized as carcinogens by the American Conference of Governmental Industrial Hygienists (ACGIH), or the International Agency for Research on Cancer (IARC). Under the U.S. OSHA Hazard Communication (Hazcom) Standard, materials are identified as carcinogens on MSDSs if they are listed as either carcinogens or potential carcinogens by IARC or the U.S. National Toxicology Program (NTP), if they are regulated as carcinogens by OSHA, or if there is valid scientific evidence in man or animals demonstrating a cancer causing potential. The lists of carcinogens published by the IARC, ACGIH and NTP include known human carcinogens and some materials which cause cancer in animal experiments. Certain

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chemicals may be listed as suspect or possible carcinogens if the evidence is limited or so variable that a definite conclusion cannot be made. Cas Registry Number - The CAS Registry Number is a number assigned to a material by the Chemical Abstracts Service (CAS) of the American Chemical Society (ACS). The CAS number provides a single unique identifier. A unique identifier is necessary because the same material can have many different names. For example, the name given to a specific chemical may vary from one language or country to another. The CAS Registry Number is similar to a telephone number and has no significance in terms of the chemical nature or hazards of the material. The CAS Registry Number can be used to locate additional information on the material, for example, when searching in books or chemical data bases. CC - Depending on the context, CC can stand for closed cup, cubic centimetres or ceiling concentration. CCC - CCC stands for Cleveland closed cup, a standard method of determining flash points. Ceiling (C) - See Exposure Limits for a general explanation. Chemical Family - The chemical family describes the general nature of the chemical. Chemicals belonging to the same family often share certain physical and chemical properties and toxic effects. However, there may also be important differences. For example, toluene and benzene both belong to the aromatic hydrocarbon family. However, benzene is a carcinogen, but toluene is not. Chemical Formula - The chemical formula, sometimes called the molecular formula, tells which elements (carbon, hydrogen, oxygen, and so on) make up a chemical. It also gives the number of atoms of each element in one unit or molecule of the chemical. The chemical formula can be used to confirm the identity of ingredients or to indicate the presence of a potentially hazardous element. For example, zinc yellow has the chemical formula ZnCrO4, which shows that it contains not only zinc (Zn) but also chromium (Cr). Chemical Name - The chemical name is a proper scientific name for an ingredient of a product. For example, the chemical name of the herbicide 2,4-D is 2,4-dichlorophenoxyacetic acid. The chemical name can be used to obtain additional information. Chemical Reactivity - Chemical reactivity is the ability of a material to undergo a chemical change. A chemical reaction may occur under conditions such as heating, burning, contact with other chemicals, or exposure to light. Undesirable effects such as pressure buildup, temperature increase or formation of other hazardous chemicals may result. (See also Dangerously Reactive Material and Reactive Flammable Material). Chronic - Chronic means long-term or prolonged. It can describe either an exposure or a health effect. A chronic exposure is a long-term exposure. Long-term means lasting for months or years. A chronic health effect is an adverse health effect resulting from long-term exposure or a persistent adverse health effect resulting from a short-term exposure. The Canadian Controlled

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Products Regulations describe technical criteria for identifying materials which cause chronic health effects. (See also Acute). CNS - CNS stands for central nervous system. COC - COC stands for Cleveland open cup, a standard method of determining flash points. COD - COD stands for chemical oxygen demand. Coefficient of Oil/Water Distribution - The coefficient of oil/water distribution, also called the partition coefficient (abbreviated as P), is the ratio of the solubility of a chemical in an oil to its solubility in water. The P value is typically presented as a logarithm of P (log P). It indicates how easily a chemical can be absorbed into or stored in the body. The P value is also used to help determine the effects of the chemical on the environment. Combustible - Combustible means able to burn. Broadly speaking, a material is combustible if it can catch fire and burn. However, in many jurisdictions, the term combustible is given a specific regulatory meaning. (See Combustible Liquid). The terms combustible and flammable both describe the ability of a material to burn. Commonly, combustible materials are less easily ignited than flammable materials. Combustible Liquid - Under the Canadian Controlled Products Regulations, a combustible liquid has a flash point from 37.8 to 93.3 degrees C using a closed cup test. The U.S. OSHA Hazcom Standard uses a similar definition. This range of flash points is well above normal room temperature. Combustible liquids are, therefore, less of a fire hazard than flammable liquids. If there is a possibility that a combustible liquid will be heated to a temperature near its flash point, appropriate precautions must be taken to prevent a fire or explosion. Compressed Gas - A compressed gas is a material which is a gas at normal room temperature and pressure but is packaged as a pressurized gas, pressurized liquid or refrigerated liquid. Regardless of whether a compressed gas is packaged in an aerosol can, a pressurized cylinder or a refrigerated container, it must be stored and handled very carefully. Puncturing or damaging the container or allowing the container to become hot may result in an explosion. Controlled Products - A controlled product is defined as a material, product or substance which is imported or sold and meets the criteria for one or more of the following classes: • •

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Class A - Compressed Gas Class B - Flammable and Combustible Material: – Division 1 - Flammable Gas – Division 2 - Flammable Liquid – Division 3 - Combustible Liquid – Division 4 - Flammable Solid – Division 5 - Flammable Aerosol – Division 6 - Reactive Flammable Material Class C - Oxidizing Material

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Class D - Poisonous and Infectious Material: – Division 1 - Material Causing Immediate and Serious Toxic  Subdivision A - Very Toxic Material  Subdivision B - Toxic Material – Division 2 - Material Causing Other Toxic Effects:  Subdivision A - Very Toxic Material  Subdivision B - Toxic Material – Division 3 - Biohazardous Infectious Material Class E - Corrosive Material Class F - Dangerously Reactive Material

Corrosive Material - A corrosive material can attack (corrode) metals or human tissues such as the skin or eyes. Corrosive materials may cause metal containers or structural materials to become weak and eventually to leak or collapse. Corrosive materials can burn or destroy human tissues on contact and can cause effects such as permanent scarring or blindness. CU M or CU.M - This stands for cubic meter. Dangerously Reactive Material - A dangerously reactive material can react vigorously: • • •

with water to produce a very toxic gas; on its own by polymerization or decomposition; or under conditions of shock, or an increase in pressure or temperature.

ANSI defines a dangerously reactive material as one that is able to undergo a violent selfaccelerating exothermic chemical reaction with common materials, or by itself. A dangerously reactive material may cause a fire, explosion or other hazardous condition. It is very important to know which conditions (such as shock, heating or contact with water) may set off the dangerous reaction so that appropriate preventive measures can be taken. Density - The density of a material is its weight for a given volume. Density is usually given in units of grams per millilitre (g/mL) or grams per cubic centimetre (g/cc). Density is closely related to specific gravity (relative density). The volume of a material in a container can be calculated from its density and weight. Dilution Ventilation - See General Ventilation. Embryo - An embryo is an organism in the early stages of its development prior to birth. In humans, the embryo is the developing child from conception to the end of the second month of pregnancy. (See also Fetus/Foetus). Embryotoxic, Embryotoxicity - Embryotoxic means harmful to the embryo. Embryotoxicity is the ability of a substance to cause harm to the embryo. Embryotoxic effects are included as Target Organ Effects.

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Engineering Controls - Engineering controls help reduce exposure to potential hazards either by isolating the hazard or by removing it from the work environment. Engineering controls include mechanical ventilation and process enclosure. They are important because they are built into the work process. Engineering controls are usually preferred to other control measures such as the use of personal protective equipment. Substitution of a less hazardous material or industrial process is the best way to reduce a hazard and is often considered to be a type of engineering control. Evaporation Rate - The evaporation rate is a measure of how quickly the material becomes a vapour at normal room temperature. Usually, the evaporation rate is given in comparison to certain chemicals, such as butyl acetate, which evaporate fairly quickly. For example, the rate might be given as "0.5 (butyl acetate=1)." This means that, under specific conditions, 0.5 grams of the material evaporates during the same time that 1 gram of butyl acetate evaporates. Often, the evaporation rate is given only as greater or less than 1, which means the material evaporates faster or slower than the comparison chemical. In general, a hazardous material with a higher evaporation rate presents a greater hazard than a similar compound with a lower evaporation rate. Explosion Data - Explosion data is information on the explosive properties of a material. Quantitative explosion data is seldom available and is usually given in descriptive terms such as low, moderate or high. The following types of information can be used to describe the explosive hazard of a material: • •

Sensitivity to mechanical impact. This information indicates whether or not the material will burn or explode on shock (for example, dropping a package) or friction (for example, scooping up spilled material). Sensitivity to static discharge. This information indicates how readily the material can be ignited by an electric spark.

Detailed information is available on the properties of commercial explosives. A chemical is identified as explosive if it causes a sudden, almost instantaneous release of pressure, gas and heat when subjected to sudden shock, pressure or high temperature. Explosive Limits - Explosive limits specify the concentration range of a material in air which will burn or explode in the presence of an ignition source (spark or flame). Explosive limits may also be called flammable limits or explosion limits. The lower explosive limit (LEL), or lower flammable limit (LFL), is the lowest concentration of gas or vapour which will burn or explode if ignited. The upper explosive limit (UEL), or upper flammable limit (UFL), is the highest concentration of gas or vapour which will burn or explode if ignited. From the LEL to the UEL, the mixture is explosive. Below the LEL, the mixture is too lean to burn. Above the UEL, the mixture is too rich to burn. However, concentrations above the UEL are still very dangerous because, if the concentration is lowered (for example, by introducing fresh air), it will enter the explosive range. In reality, explosive limits for a material vary since they depend on many factors such as air temperature. Therefore, the values given on an MSDS are approximate. The explosive limits are usually given as the percent by volume of the material in the air. One percent by volume is 10,000 ppm. For example, gasoline has a LEL of 1.4% and a UEL of 7.6%. This

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means that gasoline vapours at concentrations of 1.4% to 7.6% (14,000 to 76,000 ppm) are flammable or explosive. Exposure Limits (or Occupational Exposure Limits (OELs)) - An exposure limit is the concentration of a chemical in the workplace air to which most people can be exposed without experiencing harmful effects. Exposure limits should not be taken as sharp dividing lines between safe and unsafe exposures. It is possible for a chemical to cause health effects, in some people, at concentrations lower than the exposure limit. Exposure limits have different names and different meanings depending on who developed them and whether or not they are legal limits. For example, Threshold Limit Values (TLVs) are exposure guidelines developed by the American Conference of Governmental Industrial Hygienists (ACGIH). They have been adopted by many Canadian governments as their legal limits. Permissible Exposure Limits (PELs) are legal exposure limits in the United States. Sometimes, a manufacturer will recommend an exposure limit for a material. Exposure limits have not been set for many chemicals, for many different reasons. For example, there may not be enough information available to set an exposure limit. Therefore, the absence of an exposure limit does not necessarily mean the material is not harmful. There are three different types of exposure limits in common use: 1. Time-weighted average (TWA) exposure limit is the time-weighted average concentration of a chemical in air for a normal 8-hour work day and 40-hour work week to which nearly all workers may be exposed day after day without harmful effects. Timeweighted average means that the average concentration has been calculated using the duration of exposure to different concentrations of the chemical during a specific time period. In this way, higher and lower exposures are averaged over the day or week. 2. Short-term exposure limit (STEL) is the average concentration to which workers can be exposed for a short period (usually 15 minutes) without experiencing irritation, long-term or irreversible tissue damage, or reduced alertness. The number of times the concentration reaches the STEL and the amount of time between these occurrences can also be restricted. 3. Ceiling (C) exposure limit is the concentration which should not be exceeded at any time. SKIN notation (SKIN) means that contact with the skin, eyes and moist tissues (for example, the mouth) can contribute to the overall exposure. The purpose of this notation is to suggest that measures be used to prevent absorption by these routes; for example, the use of protective gloves. If absorption occurs through the skin, then the airborne exposure limits are not relevant. Extinguishing Media - Extinguishing media are agents which can put out fires involving the material. Common extinguishing agents are water, carbon dioxide, dry chemical, "alcohol" foam, and halogenated gases (Halons). It is important to know which extinguishers can be used so they can be made available at the worksite. It is also important to know which agents cannot be used since an incorrect extinguisher may not work or may create a more hazardous situation. If several materials are involved in a fire, an extinguisher effective for all of the materials should be used. Fetotoxic, Fetotoxicity - Fetotoxic means the substance is harmful to the fetus/foetus. Fetotoxicity describes the ability of a substance to harm the fetus. (See also Embryotoxicity, Teratogenicity and Reproductive Effects).

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Fetus/Foetus - A fetus is an organism in the later stages of development prior to birth. In humans, it is the unborn child from the end of the second month of pregnancy to birth. (See also Embryo). First Aid - First aid is emergency care given immediately to an injured person. The purpose of first aid is to minimize injury and future disability. In serious cases, first aid may be necessary to keep the victim alive. Flammable, Flammability - Flammable means able to ignite and burn readily. Flammability is the ability of a material to ignite and burn readily. (See also Combustible). Under the Canadian Controlled Products Regulations and the U.S. HAZCOM Standard, there are specific technical criteria for identifying flammable materials. (See Flammable Aerosol, Flammable Gas, Flammable Liquid, Flammable Solid and Reactive Flammable Material). Flammable Aerosol - Under the Canadian Controlled Products Regulations, a material is identified as a flammable aerosol if it is packaged in an aerosol container which can release a flammable material. A flammable aerosol is hazardous because it may form a torch (explosive ignition of the spray) or because a fire fueled by the flammable aerosol may flash back. Flammable and Combustible Material - A material may be classified as a flammable and combustible material if it meets specific criteria for a flammable gas, flammable liquid, combustible liquid, flammable solid, flammable aerosol or reactive flammable material. Flammable Gas - A flammable gas is a gas which can ignite readily and burn rapidly or explosively. Under the Canadian Controlled Products Regulations and under the U.S. Hazard Communication Standard, there are certain technical criteria for the identification of materials as flammable gases for the purposes of each regulation. Flammable gases can be extremely hazardous in the workplace; for example: • •

If the gas accumulates so that its lower explosive limit (LEL) is reached and if there is a source of ignition, an explosion may occur. If there is inadequate ventilation, flammable gases can travel a considerable distance to a source of ignition and flash back to the source of the gas.

Flammable Limits - See Explosive Limits. Flammable Liquid - A flammable liquid gives off a vapour which can be readily ignited at normal working temperatures. Under the Canadian Controlled Products Regulations, a flammable liquid is a liquid with a flash point (using a closed cup test) below 37.8 degrees C. The U.S. Hazard Communication Standard uses a similar, but not identical, definition. Flammable liquids can be extremely hazardous in the workplace; for example: • •

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If there is inadequate ventilation, vapours can travel considerable distances to a source of ignition and flash back to the flammable liquid. It may be difficult to extinguish a burning flammable liquid with water because water may not be able to cool the liquid below its flash point.

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Flammable Solid - A flammable solid is a material which can ignite readily and burn vigorously and persistently. There are certain technical criteria in the Canadian Controlled Products Regulations and in the U.S. OSHA Hazard Communication Standard for the identification of flammable solids for the purposes of each regulation. These criteria are based on ease of ignition and rate of burning. Flammable solids may be hazardous because heat from friction (for example, surfaces rubbing together) or heat from processing may cause a fire. Flammable solids in the form of a dust or powder may be particularly hazardous because they may explode if ignited. Flash Back - Flash back occurs when a trail of flammable gas, vapor or aerosol is ignited by a distant spark, flame or other source of ignition. The flame then travels back along the trail of gas, vapour or aerosol to its source. A serious fire or explosion could result. Flash Point - The flash point is the lowest temperature at which a liquid or solid gives off enough vapour to form a flammable air-vapour mixture near its surface. The lower the flash point, the greater the fire hazard. The flash point is an approximate value and should not be taken as a sharp dividing line between safe and hazardous conditions. The flash point is determined by a variety of test methods which give different results. Two types of methods are abbreviated as OC (open cup) and CC (closed cup). Freezing Point - See Melting Point. Fumes - Fumes are very small, airborne, solid particles formed by the cooling of a hot vapour. For example, a hot zinc vapour may form when zinc-coated steel is welded. The vapour then condenses to form fine zinc fume as soon as it contacts the cool surrounding air. Fumes are smaller than dusts and are more easily breathed into the lungs. Gas - Gas is a material without a specific shape or volume. Gases tend to occupy an entire space uniformly at normal room pressure and temperature. The terms vapour and fume are sometimes confused with gas. General Ventilation - As used in an MSDS, general ventilation, also known as dilution ventilation, is the removal of contaminated air from the general area and the bringing in of clean air. This dilutes the amount of contaminant in the work environment. General ventilation is usually suggested for non-hazardous materials. (See also Mechanical Ventilation, Local Exhaust Ventilation and Ventilation). GI - GI stands for gastrointestinal (relating to the stomach and intestines). Hazard, Hazardous - Hazard is the potential for harmful effects. Hazardous means potentially harmful. The hazards of a material are evaluated by examining the properties of the material, such as toxicity, flammability and chemical reactivity, as well as how the material is used. How a material is used can vary greatly from workplace to workplace and, therefore, so can the hazard. In Canada and the U.S., the term hazardous is used by many different regulatory agencies. Definitions may vary. For example, OSHA defines a hazardous chemical as any chemical which

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is a physical hazard or a health hazard according to the OSHA Hazard Communication (Hazcom) criteria. Hazardous Combustion Products - Hazardous combustion products are chemicals which may be formed when a material burns. These chemicals may be toxic, flammable or have other hazards. The chemicals released and their amounts vary, depending upon conditions such as the temperature and the amount of air (or more specifically, oxygen) available. The combustion chemicals may be quite different from those formed by heating the same material during processing (thermal decomposition products). It is important to know which chemicals are formed by hazardous combustion in order to plan the response to a fire involving the material. Hazardous Decomposition Products - Hazardous decomposition products are formed when a material decomposes (breaks down) because it is unstable, or reacts with common materials such as water or oxygen (in air). This information should be considered when planning storage and handling procedures. Hazardous Ingredient - Under the Canadian Hazardous Products Act, a chemical must be listed in the Hazardous Ingredients Section of an MSDS if: • • • •

it meets the criteria for a controlled product; it is on the Ingredient Disclosure List; there is no toxicological information available; or the supplier has reason to believe it might be hazardous.

Certain chemicals may be exempt from disclosure on an MSDS if they meet specific criteria set out in the Hazardous Materials Information Review Act. Hazardous Polymerization - See Polymerize, Polymerization. Hepatotoxin - Hepatotoxins are agents that can cause toxic effects on the liver. Highly Toxic - Under the U.S. OSHA HAZCOM Standard, there are specific criteria for materials which must be identified as toxic. The corresponding term under Canadian WHMIS is "Very Toxic" (criteria are not the same). HR - HR stands for hour. IARC - IARC stands for the International Agency for Research on Cancer. IARC evaluates information on the carcinogenicity of chemicals, groups of chemicals and chemicals associated with certain industrial processes. IARC has published lists of chemicals which are generally recognized as human carcinogens, probable human carcinogens or carcinogens in animal tests. IATA - IATA stands for International Air Transport Association. IDLH - IDLH stands for Immediately Dangerous to Life or Health. For the purposes of respirator selection, NIOSH defines the IDLH concentration as the airborne concentration that

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poses a threat of exposure to airborne contaminants when that exposure is likely to cause death or immediate or delayed permanent adverse health effects or prevent escape from such an environment. The purpose of establishing an IDLH exposure concentration is to ensure that the worker can escape from a given contaminated environment in the event of failure of the respiratory protection equipment. In the event of failure of respiratory protective equipment, every effort should be made to exit immediately. Impervious - On an MSDS, impervious is a term used to describe protective gloves and other protective clothing. If a material is impervious to a chemical, then that chemical cannot readily penetrate through the material or damage the material. Different materials are impervious (resistant) to different chemicals. No single material is impervious to all chemicals. If an MSDS recommends wearing impervious gloves, you need to know the type of material from which the gloves should be made. For example, neoprene gloves are impervious to butyl alcohol but not to ethyl alcohol. Incompatible Materials - Incompatible materials can react with the product or with components of the product and may: • • •

destroy the structure or function of a product; cause a fire, explosion or violent reaction; or cause the release of hazardous chemicals.

Inert Ingredient - An inert ingredient is anything other than the active ingredient of a product. It may be a solvent, colorant, filler or dispersing agent. In some cases, inert ingredients may be hazardous. Ingestion - Ingestion means taking a material into the body by mouth (swallowing). Inhalation - Inhalation means taking a material into the body by breathing it in. Irritancy, Irritation - Irritancy is the ability of a material to irritate the skin, eyes, nose, throat or any other part of the body that it contacts. Signs and symptoms of irritation include tearing in the eyes and reddening, swelling, itching and pain of the affected part of the body. Irritancy is often described as mild, moderate or severe, depending on the degree of irritation caused by a specific amount of the material. Irritancy may also be described by a number on a scale of 0 to 4, where 0 indicates no irritation and 4 means severe irritation. Irritancy is usually determined in animal experiments. ISO - ISO stands for the International Standards Organization. KG - KG stands for kilogram Kow - Kow stands for octanol/water partition coefficient.

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LC50 - LC stands for lethal concentration. LC50 is the concentration of a material in air which causes the death of 50% (one half) of a group of test animals. The material is inhaled over a set period of time, usually 1 or 4 hours. The LC50 helps determine the short-term poisoning potential of a material. LD50 - LD stands for lethal dose. LD50 is the amount of a material, given all at once, which causes the death of 50% (one half) of a group of test animals. The LD50 can be determined for any route of entry, but dermal (applied to skin) and oral (given by mouth) LD50's are most common. The LD50 is one measure of the short-term poisoning potential of a material. (See also LC50). LCLO - LCLO stands for lowest lethal airborne concentration tested. (See also LC50 and LD50). LDLO - LDLO stands for lowest lethal dose tested. (See also LC50 and LD50). LEL - See Explosive Limits. LFL - See Explosive Limits. Local Exhaust Ventilation - Local exhaust ventilation is the removal of contaminated air directly at its source. This type of ventilation can help reduce worker exposure to airborne materials more effectively than general ventilation. This is because it does not allow the material to enter the work environment. It is usually recommended for hazardous airborne materials. (See also Mechanical Ventilation and Ventilation). Lower Explosion Limit - See Explosive Limits. Lower Explosive Limit - See Explosive Limits. Lower Flammable Limit - See Explosive Limits. Material Causing Immediate and Serious Toxic Effects - The Canadian Controlled Products Regulations describe technical criteria for identifying materials which cause immediate and serious toxic effects. These criteria use information such as the LD50 or LC50 for a material. Based on the specific information, a material may be identified as toxic or very toxic in the class Poisonous and Infectious Material. Material Causing Other Toxic Effects - The Canadian Controlled Products Regulations describe technical criteria for identifying materials which cause toxic effects such as skin or respiratory sensitization, mutagenicity and carcinogenicity. Based on the specific information, a material may be identified as toxic or very toxic in the class Poisonous and Infectious Material. Means Of Extinction - See Extinguishing Media.

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Mechanical Ventilation - Mechanical ventilation is the movement of air by mechanical means (for example, a wall fan). There are two kinds of mechanical ventilation: general ventilation and local exhaust ventilation. (See also Ventilation). Melting Point - The melting point is the temperature at which a solid material becomes a liquid. The freezing point is the temperature at which a liquid material becomes a solid. Usually one value or the other is given on the MSDS. It is important to know the freezing or melting point for storage and handling purposes. For example, a frozen or melted material may burst a container. As well, a change of physical state could alter the hazards of the material. mg/m3 - The abbreviation mg/m3 stands for milligrams (mg) of a material per cubic metre (m3) of air. It is a unit of metric measurement for concentration (weight/volume). The concentrations of any airborne chemical can be measured in mg/m3, whether it is a solid, liquid, gas or vapor. MIN - MIN can stand for minute or minimum. Miscible - Miscible means able to be mixed. Two liquids are said to be miscible if they are partially or completely soluble in each other. Commonly, the term miscible is understood to mean that the two liquids are completely soluble in each other. (See also Solubility). Mist - A mist is a collection of liquid droplets suspended in air. A mist can be formed when spraying or splashing a liquid. It can also be formed when a vapour condenses into liquid droplets in the air. (See also Aerosol). ML - ML stands for millilitres (mL). mm Hg - The abbreviation mm Hg stands for millimeters (mm) of mercury (Hg). It is a common unit of measurement for the pressure exerted by gases such as air. Normal atmospheric pressure is 760 mm Hg. Molecular Formula - See Chemical Formula. Molecular Weight - The molecular weight of a chemical is a number showing how heavy one molecule (or unit) of the chemical is compared to the lightest element, hydrogen, which has a weight of 1. The molecular weight has various technical uses, such as calculating conversions from parts per million (ppm) to milligrams per cubic metre (mg/m3) in air. Mutagen, Mutagenic, Mutagenicity - A mutagen is a substance which can cause changes in the DNA of cells (mutations). Mutagenic means able to cause mutations. Mutagenicity is the ability of a substance to cause mutations. DNA determines the characteristics that children inherit from their parents. DNA also determines how cells in the body divide or reproduce. A number of mutagenicity tests are used to screen chemicals for possible carcinogenicity or reproductive effects. This is because there is some evidence that mutations may increase the risk of cancer and reproductive problems such as infertility or birth defects. However, mutagenicity test results are not very reliable predictors of these effects. One reason for this is that the human body can repair mutations while most mutagenicity tests cannot. Mutagenicity is included on MSDSs because it

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is an early indicator of potential hazard, and often there is very little other evidence available on possible carcinogenic or reproductive effects. The Canadian Controlled Products Regulations describes technical criteria for identifying materials which are mutagenic. The U.S. OSHA HAZCOM Standard includes mutagenic effects as reproductive target organ effects. Natural Ventilation - Natural ventilation is a type of general ventilation which depends on natural instead of mechanical means for air movement. Natural ventilation can depend on the wind or the difference in temperature from one area to another to move air through a building. Therefore, it is unpredictable and unreliable. (See also Local Exhaust Ventilation, Mechanical Ventilation and Ventilation). Nephrotoxins - Nephrotoxins are agents that can cause toxic effects on the kidney. Neurotoxins - Neurotoxins are agents that can cause toxic effects on the nervous system. NFPA - NFPA stands for National Fire Protection Association (U.S.). NIOSH - NIOSH stands for National Institute for Occupational Safety and Health. NIOSH is a branch of the United States government which undertakes research and develops occupational health and safety standards. NOEL - NOEL stands for No Observable Effect Level. NOS - NOS stands for not otherwise specified. NTP - NTP stands for National Toxicology Program. This program is part of the United States Department of Health and Human Services. The NTP has a large program for testing the potential carcinogenicity of chemicals. It also does many other types of studies on short-term and long-term health effects. OC - OC stands for open cup. Odor Threshold - The odor threshold is the lowest concentration of a chemical in air that is detectable by smell. The odor threshold should only be regarded as an estimate. This is because odor thresholds are commonly determined under controlled laboratory conditions using people trained in odor recognition. As well, in the workplace, the ability to detect the odor of a chemical varies from person to person and depends on conditions such as the presence of other odorous materials. Odor cannot be used as a warning of unsafe conditions since workers may become used to the smell (adaptation), or the chemical may numb the sense of smell, a process called olfactory fatigue. However, if the odor threshold for a chemical is well below its exposure limit, odor can be used to warn of a problem with your respirator. OECD - OECD stands for Organization for Economic Cooperation and Development. The OECD is an international agency which supports programs designed to facilitate trade and development. The OECD has published "Guidelines for Testing of Chemicals." These guidelines

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contain recommended procedures for testing chemicals for toxic and environmental effects and for determining physical and chemical properties. OEL - OEL stands for Occupational Exposure Limit. (See Exposure Limits for a general explanation). OSHA - OSHA stands for Occupational Safety and Health Administration. It is the branch of the United States government which sets and enforces occupational health and safety regulations. For example, OSHA sets the legal exposure limits in the United States, which are called Permissible Exposure Limits (PELs). OSHA also specifies what information must be given on labels and Material Safety Data Sheets for materials which have been classified as hazardous using their criteria. Oxidizing Agent, Oxidizing Material - An oxidizing agent or material gives up oxygen easily or can readily oxidize other materials. Examples of oxidizing agents are oxygen, chlorine and peroxide compounds. These chemicals will support a fire and are highly reactive. Under the Canadian Controlled Products Regulations and under the U.S. OSHA Hazcom Standard, there are specific criteria for the classification of materials as oxidizing materials. Particulates Not Otherwise Classified (PNOC) - Particulates not otherwise classified is a term defined by the ACGIH. It is used to describe particulates for which there is no evidence of specific toxic effects such as fibrosis or systemic effects. These material are not to be considered inert, however, and can produce general toxic effects depending on the airborne concentration. Partition Coefficient - See Coefficient of Oil/Water Distribution. PEL - PEL stands for Permissible Exposure Limit. PELs are legal limits in the United States set by the Occupational Safety and Health Administration (OSHA). (See Exposure Limits for a general explanation). Pensky-Martens Closed Cup - Pensky-Martens Closed Cup (PMCC) is a specific method for determining flash points. Personal Protective Equipment - Personal protective equipment is clothing or devices worn to help isolate a person from direct exposure to a hazardous material or situation. Recommended personal protective equipment is often listed on an MSDS. This can include protective clothing, respiratory protection and eye protection. The use of personal protective equipment is the least preferred method of protection from hazardous exposures. It can be unreliable and, if it fails, the person can be left completely unprotected. This is why engineering controls are preferred. Sometimes, personal protective equipment may be needed along with engineering controls. For example, a ventilation system (an engineering control) reduces the inhalation hazard of a chemical, while gloves and an apron (personal protective equipment) reduce skin contact. In addition, personal protective equipment can be an important means of protection when engineering controls are not practical: for example, during an emergency or other temporary conditions such as maintenance operations.

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pH - The pH is a measure of the acidity or basicity (alkalinity) of a material when dissolved in water. It is expressed on a scale from 0 to 14. Roughly, pH can be divided into the following ranges: • pH 0 - 2 Strongly acidic • pH 3 - 5 Weakly acidic • pH 6 - 8 Neutral • pH 9 - 11 Weakly basic • pH 12 - 14 Strongly basic. PMCC - See Pensky-Martens Closed Cup. PNS - PNS stands for peripheral nervous system. Poisonous And Infectious Material - Under the Canadian Controlled Products Regulations, a Poisonous and Infectious Material is any material which meets the criteria for a Material Causing Immediate and Serious Toxic Effects, a Material Causing Other Toxic Effects, or a Biohazardous Infectious Material. Polymer - A polymer is a natural or man-made material formed by combining units, called monomers, into long chains. The word polymer means many parts. Examples of polymers are starch (which has many sugar units), polyethylene (which has many ethylene units) and polystyrene (which has many styrene units). Most man-made polymers have low toxicity, low flammability and low chemical reactivity. In these ways, polymers tend to be less hazardous than the chemicals (monomers) from which they are made. Polymerize, Polymerization - Polymerization is the process of forming a polymer by combining large numbers of chemical units or monomers into long chains. Polymerization can be used to make some useful materials. However, uncontrolled polymerization can be extremely hazardous. Some polymerization processes can release considerable heat, can generate enough pressure to burst a container or can be explosive. Some chemicals can polymerize on their own without warning. Others can polymerize upon contact with water, air or other common chemicals. Inhibitors are normally added to products to reduce or eliminate the possibility of uncontrolled polymerization. Most MSDSs have a section called "Hazardous Polymerization" which indicates whether hazardous polymerization reactions can occur. Ppb - ppb stands for parts per billion. Ppm - The abbreviation ppm stands for parts per million. It is a common unit of concentration of gases or vapour in air. For example, 1 ppm of a gas means that 1 unit of the gas is present for every 1 million units of air. One ppm is the same as 1 minute in 2 years or 1 cent in $10,000. Process Enclosure - As used on an MSDS, process enclosure means that the operation in which the material is used is completely enclosed. A physical barrier separates the worker from the potential health or fire hazard. Process enclosure is usually recommended if the material is very toxic or flammable.

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Pyrophoric - Pyrophoric chemicals are defined in the U.S. OSHA Hazcom Standard as chemicals which will ignite spontaneously in air at a temperature of 54.4 degrees C or below. Regulatory definitions in other jurisdictions may differ. Reactive Flammable Material - Under the Canadian Controlled Products Regulations, a reactive flammable material is a material which is a dangerous fire risk because it can react readily with air or water. This category includes any material which: • • • •

is spontaneously combustible, that is, a material which can react with air until enough heat builds up that it begins to burn; can react vigorously with air under normal conditions without actually catching fire; gives off dangerous quantities of flammable gas on reaction with water; or becomes spontaneously combustible when it contacts water or water vapour.

Reactive flammable materials must be kept dry and isolated from oxygen (in air) or other oxidizing agents. Therefore, they are often stored and handled in an atmosphere of unreactive gas, such as nitrogen or argon. Relative Density - See Specific Gravity. Reproductive Effects - Reproductive effects are problems in the reproductive process which may be caused by a substance. Possible reproductive effects include reduced fertility in the male or female, menstrual changes, miscarriage, embryotoxicity, fetotoxicity, teratogenicity, or harmful effects to the nursing infant from chemicals in breast milk. Most chemicals can cause reproductive effects if there is an extremely high exposure. In these cases, the exposed person would experience other noticeable signs and symptoms caused by the exposure. These signs and symptoms act as a warning of toxicity. Chemicals which cause reproductive effects in the absence of other significant harmful effects are regarded as true reproductive hazards. Very few workplace chemicals are known to be true reproductive hazards. Reproductive Toxicity - The Canadian Controlled Products Regulations describe technical criteria for identifying materials which have reproductive toxicity. These criteria refer to adverse effects on fertility. (See also Reproductive Effects). Other jurisdictions likely have corresponding criteria, which may differ. Under the U.S. OSHA HAZCOM Standard, Reproductive Toxicity is a Target Organ Effect, and includes mutagens, embryotoxins, teratogens and reproductive toxins. Respiratory Sensitization - See Sensitization. RTECS - RTECS stands for Registry of Toxic Effects of Chemical Substances. SARA - SARA stands for Superfund Amendments and Reauthorization Act of 1986 (U.S.). SEC - SEC stands for second or section. Sensitization - Sensitization is the development, over time, of an allergic reaction to a chemical. The chemical may cause a mild response on the first few exposures but, as the allergy develops,

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the response becomes worse with subsequent exposures. Eventually, even short exposures to low concentrations can cause a very severe reaction. There are two different types of occupational sensitization: skin and respiratory. Typical symptoms of skin sensitivity are swelling, redness, itching, pain, and blistering. Sensitization of the respiratory system may result in symptoms similar to a severe asthmatic attack. These symptoms include wheezing, difficulty in breathing, chest tightness, coughing and shortness of breath. The Canadian Controlled Products Regulations and the U.S. OSHA HAZCOM Standard describe technical criteria for identifying materials which are respiratory tract sensitizers or skin sensitizers. Skin Notation - See Exposure Limits for a general explanation. Skin Sensitization - See Sensitization. Solubility - Solubility is the ability of a material to dissolve in water or another liquid. Solubility may be expressed as a ratio or may be described using words such as insoluble, very soluble or miscible. Often, on an MSDS, the "Solubility" section describes solubility in water since water is the single most important industrial solvent. Solubility information is useful for planning spill clean-up and fire fighting procedures. Solvent - A solvent is a material, usually a liquid, which is capable of dissolving another chemical. Chemicals commonly called solvents can dissolve many different chemicals. Examples of common solvents are water, ethanol, acetone, hexane and toluene. Specific Gravity - Specific gravity is the ratio of the density of a material to the density of water. The density of water is about 1 gram per cubic centimetre (g/cc). Materials which are lighter than water (specific gravity less than 1.0) will float. Most materials have specific gravities exceeding 1.0, which means they are heavier than water and so will sink. Knowing the specific gravity is important for planning spill clean-up and fire fighting procedures. For example, a light flammable liquid such as gasoline may spread and, if ignited, burn on top of a water surface. Stability - Stability is the ability of a material to remain unchanged in the presence of heat, moisture or air. An unstable material may decompose, polymerize, burn or explode under normal environmental conditions. Any indication that the material is unstable gives warning that special handling and storage precautions may be necessary. STEL - STEL stands for Short-Term Exposure Limit. (See Exposure Limits for a general explanation). STP - STP stands for Standard Temperature and Pressure (0 degrees Celsius and one atmosphere pressure). Synergistic, Synergism - As used on an MSDS, synergism means that exposure to more than one chemical can result in health effects greater than expected when the effects of exposure to each chemical are added together. Very simply, it is like saying 1 + 1 = 3. When chemicals are synergistic, the potential hazards of the chemicals should be re-evaluated, taking their synergistic properties into consideration.

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Synonyms - Synonyms are alternative names for the same chemical. For example, methanol and methyl hydrate are synonyms for methyl alcohol. Synonyms may help in locating additional information on a chemical. Target Organ Effects - Under the U.S. OSHA HAZCOM Standard, chemicals are identified as having target organ effects if there is statistically significant evidence of an acute or chronic health effect determined in a scientifically valid study. The following agents would be included (note, the list is not all- inclusive): hepatotoxins, agents which damage the lungs (including irritants), agents which act on the hematopoietic system, neurotoxins, nephrotoxins, reproductive toxins (mutagens, embryotoxins, teratogens and reproductive toxins), cutaneous hazards (chemicals which affect the dermal layer of the skin) and eye hazards (chemicals which affect the eye or visual capacity). There are no maximum dose criteria for chronic toxicity studies, as specified in the Canadian Controlled Products Regulations. TCC - TCC stands for Tagliabue closed cup; a standard method of determining flash points. Generally, this appears in abbreviated form as Tag closed cup. TCLO - TCLO stands for lowest toxic airborne concentration tested (see also LCLO and LC50). Teratogen, Teratogenic, Teratogenicity - A teratogen is a substance which can cause birth defects. Teratogenic means able to cause birth defects. Teratogenicity is the ability of a chemical to cause birth defects. Teratogenicity results from a harmful effect to the embryo or the fetus/foetus. The Canadian Controlled Products Regulations describe technical criteria for identifying materials which have teratogenicity and embryotoxicity. (See also Reproductive Effects). Other jurisdictions may also have defined specific criteria. Under the U.S. OSHA HAZCOM Standard, materials which have teratogenic effects are included under reproductive Target Organ Effects. Thermal Decomposition Products - Thermal decomposition products are chemicals which may be formed when the material is heated but does not burn. These chemicals may be toxic, flammable or have other hazards. The chemicals released and their amounts vary depending upon conditions such as the temperature. The thermal decomposition products may be quite different from the chemicals formed by burning the same material (hazardous combustion products). It is important to know which chemicals are formed by thermal decomposition because this information is used to plan ventilation requirements for processes where a material may be heated. TLM - TLM stands for Threshold Limit, median (aquatic toxicity rating). TLV - TLV stands for Threshold Limit Value. It is the occupational exposure limit established by the American Conference of Governmental Industrial Hygienists (ACGIH). TLV is a registered trademark of ACGIH. TLVs are adopted by some governments as their legal limits. (See Exposure Limits for a general explanation).

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TLV-C - TLV-C stands for the ACGIH Threshold Limit Value-Ceiling. See also TLV. TOC - TOC stands for Tagliabue open cup; a standard method of determining flash points. Generally, this appears in abbreviated form as Tag open cup. Toxic, Toxicity - Toxic means able to cause harmful health effects. Toxicity is the ability of a substance to cause harmful health effects. Descriptions of toxicity (e.g. low, moderate, severe, etc). depend on the amount needed to cause an effect or the severity of the effect. Under the Canadian Controlled Products Regulations and the U.S. OSHA HAZCOM Standard, there are specific technical criteria for identifying a material as toxic for the purpose of each regulation. (See also Very Toxic and Highly Toxic). Trade Name - A trade name is the name under which a product is commercially known. Some materials are sold under common names, such as Stoddard solvent or degreaser, or internationally recognized trade names, like Varsol. Trade names are sometimes identified by symbols such as (R) or (TM). TWA - TWA stands for Time-Weighted Average. (See Exposure Limits for a general explanation). UEL - See Explosive Limits. UFL - See Explosive Limits. uG - uG stands for microgram, a unit of mass. UN - UN stands for United Nations. See also UN Number. UN Number- UN number stands for United Nations number. The UN number is a four-digit number assigned to a potentially hazardous material (such as gasoline, UN 1203) or class of materials (such as corrosive liquids, UN 1760). These numbers are used by firefighters and other emergency response personnel for identification of materials during transportation emergencies. UN (United Nations) numbers are internationally recognized. NA (North American) numbers are used only for shipments within Canada and the United States. PINs (Product Identification Numbers) are used in Canada. UN, NA and PIN numbers have the same uses. Unstable (reactive) - Under the U.S. OSHA HAZCOM standard, a chemical is identified as unstable (reactive) if in the pure state, or as produced or transported, it will vigorously polymerize, decompose, condense, or will become self-reactive under conditions of shock, pressure or temperature. Upper Explosion Limit - See Explosive Limits. Upper Explosive Limit - See Explosive Limits. Upper Flammable Limit - See Explosive Limits.

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Vapor - A vapour is the gaseous form of a material which is normally solid or liquid at room temperature and pressure. Evaporation is the process by which a liquid is changed into a vapor. Sublimation is the process by which a solid is changed directly into the vapor state. Vapor Density - Vapor density is the weight per unit volume of a pure gas or vapor. On an MSDS, the vapor density is commonly given as the ratio of the density of the gas or vapor to the density of air. The density of air is given a value of 1. Light gases (density less than 1) such as helium rise in air. If there is inadequate ventilation, heavy gases and vapors (density greater than 1) can accumulate in low-lying areas such as pits and along floors. Vapor Pressure - Vapor pressure is a measure of the tendency of a material to form a vapor. The higher the vapor pressure, the higher the potential vapour concentration. In general, a material with a high vapor pressure is more likely to be an inhalation or fire hazard than a similar material with a lower vapor pressure. Ventilation - Ventilation is the movement of air. One of the main purposes of ventilation is to remove contaminated air from the workplace. There are several different kinds of ventilation. (See General Ventilation, Local Exhaust Ventilation, Mechanical Ventilation and Natural Ventilation). Very Toxic - Under the Canadian Controlled Products Regulations, there are specific technical criteria for identifying a very toxic material. There are specific criteria for short-term lethality, long-term toxicity, teratogenicity and embryotoxicity, reproductive toxicity, carcinogenicity, respiratory sensitization and mutagenicity. (See also Toxic). Under the U.S. OSHA Hazcom Standard, the corresponding term is "highly toxic", which has a specific definition. VOC - VOC stands for volatile organic compound. Volatile, Volatility - Volatile means a material can evaporate. Volatility is the ability of a material to evaporate. The term volatile is commonly understood to mean that a material evaporates easily. On an MSDS, volatility is commonly expressed as the "% volatile." The percent volatile can vary from 0% (none of the material will evaporate) to 100% (all of the material will evaporate if given enough time). If a product contains volatile ingredients, there may be a need for ventilation and other precautions to control vapor concentrations. Water Reactive - Under the U.S. OSHA HAZCOM standard, a chemical is identified as water reactive if it reacts with water to release a gas that is either flammable or presents a health hazard. 2(e)(2)(ii) Occupational Safety and Health Administration The United States Occupational Safety and Health Administration is an agency of the United States Department Labor signed into existence by President Richard Nixon in 1970 under the Occupational Safety and Health Act. The intent of enforcing standards for the workplace is to prevent work-related injuries, illnesses, and deaths.

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Standards for approximately 500 chemicals have been designated by OSHA and can be found in Tables 6 and 7.5, 6 Exposure to any of the substances listed in Tables 6 and 7 is to be limited in accordance with the requirements listed in the tables. OSHA sets enforceable permissible exposure limits (PELs) for airborne chemicals to protect workers against the health effects of exposure to hazardous substances. PELs are regulatory limits on the amount or concentration of a substance in the air. They may also contain a skin designation. OSHA PELs are based on an 8hour time weighted average (TWA) exposure. Existing PEL values can be found in the Code of Federal Regulations 29, section 1910.1000. Ceiling values, the exposure limit is preceded by a (c), indicates that at no time can the exposure exceed the exposure limit for that substance. Acceptable ceiling concentrations indicate that exposure to any substance on Table 7 is not to exceed the exposure limit at anytime within 8 hours, except for a time period not exceeding the maximum duration and concentration allowed indicated in the “acceptable maximum peak above the acceptable ceiling concentration for an eight-hour shift.. All other chemical exposures are 8-hour time weighted averages. Exposure to these substances can not exceed the exposure limit in any eight hour period.7 For example, suppose substance X has a 15ppm TWA, 30ppm ceiling, and 60ppm peak. An employee is exposed to a concentration of this substance above 40ppm but never above 60ppm for only a maximum period of 10 minutes. For the remainder of the eight hour shift, exposure can not exceed 15ppm so that the cumulative exposure does not exceed the weighted average of 15ppm. The cumulative exposure for an 8-hour work shift is computed as follows: E = (Ca Ta+Cb Tb+. . .Cn Tn)/8 Where, E is the equivalent exposure for the working shift. C is the concentration during any period of time T where the concentration remains constant. T is the duration in hours of the exposure at the concentration C. The value of E shall not exceed the 8-hour time weighted average specified in Subpart Z or 29 CFR Part 1910 for the substance involved. To illustrate the use of the formula above, assume that Substance Z has an 8-hour time weighted average limit of 100ppm. Suppose an employee is subject to the following exposure: Two hours exposure at 150ppm Two hours exposure at 75ppm Four hours exposure at 50ppm Substitution into the formula gives: (2×150 + 2×75 + 4×50)÷8 = 81.25ppm

5

Table 6 reference Table 7 reference 7 http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9991 6

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Since 81.25ppm is less than 100ppm, the 8-hour time weighted average limit, the exposure is acceptable. OSHA has also established Immediately Dangerous to Life and Health (IDLH) standards. IDLH is the concentration of an airborne chemical which may cause irreversible health effects or death. OSHA standards are broad enough to include oxygen deficient circumstances that are free from air contaminants (Table 8). Usually IDLH values are used to determine selection of proper breathing apparatus that must be available to workers in a given situation.8 Exposure limits have been used by industrial hygienists for over 50 years as a means of protecting worker health. By implementing these standards as a part of an occupational health and safety program, they are a primary tool in disease prevention. 2(e)(2)(iii) National Institute for Occupational Safety and Health The National Institute for Occupational Safety and Health (NIOSH) is the United States federal agency responsible for conducting research and making recommendations for the prevention of work-related injury and illness. NIOSH is part of the Centers for Disease Control and Prevention (CDC) within the U.S. Department of Health and Human Services. The NIOSH Pocket Guide to Chemical Hazards is intended as a source of general industrial hygiene information for workers, employers, and occupational health professionals. The Pocket Guide presents key information and data in abbreviated tabular form for 677 chemicals or substance groupings (e.g., manganese compounds, tellurium compounds, inorganic tin compounds, etc.) that are found in the work environment. The industrial hygiene information found in the Pocket Guide should help users recognize and control occupational chemical hazards. The chemicals or substances contained in this revision include all substances for which the National Institute for Occupational Safety and Health (NIOSH) has recommended exposure limits (RELs) and recommended short term exposure limits (STEL).9 These chemical standards have been complied in Table 9. For NIOSH RELs, “TWA” indicates a time-weighted average concentration for up to a 10-hour workday during a 40-hour workweek. A short-term exposure limit (STEL) is designated by “ST” preceding the value; unless noted otherwise, the STEL is a 15-minute TWA exposure that should not be exceeded at any time during a workday. A ceiling REL is designated by “C” preceding the value; unless noted otherwise, the ceiling value should not be exceeded at any time. In 1974, NIOSH (which is responsible for recommending health and safety standards) joined OSHA (whose jurisdictions include promulgation and enforcement activities) in developing a series of occupational health standards for substances with existing PELs. This joint effort was labeled the Standards Completion Program and involved the cooperative efforts of several contractors and personnel from various divisions within NIOSH and OSHA. The Standards Completion Program developed 380 substance-specific draft standards with supporting 8 9

http://en.wikipedia.org/wiki/ http://www.cdc.gov/niosh/npg/pgintrod.html#chemicalname

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documentation that contained technical information and recommendations needed for the promulgation of new occupational health regulations. Acting under the authority of the Occupational Safety and Health Act of 1970 (29 USC Chapter 15) and the Federal Mine Safety and Health Act of 1977 (30 USC Chapter 22), NIOSH develops and periodically revises recommended exposure limits (RELs) for hazardous substances or conditions in the workplace. NIOSH also recommends appropriate preventive measures to reduce or eliminate the adverse health and safety effects of these hazards. To formulate these recommendations, NIOSH evaluates all known and available medical, biological, engineering, chemical, trade, and other information relevant to the hazard. These recommendations are then published and transmitted to OSHA and the Mine Safety and Health Administration (MSHA) for use in promulgating legal standards. The purpose for establishing an IDLH value in the Standards Completion Program was to determine the airborne concentration from which a worker could escape without injury or irreversible health effects from an IDLH exposure in the event of the failure of respiratory protection equipment. The IDLH was considered a maximum concentration above which only a highly reliable breathing apparatus providing maximum worker protection should be permitted. In determining IDLH values, NIOSH considered the ability of a worker to escape without loss of life or irreversible health effects along with certain transient effects, such as severe eye or respiratory irritation, disorientation, and in coordination, which could prevent escape. As a safety margin, IDLH values are based on effects that might occur as a consequence of a 30minute exposure. LEL indicates that the IDLH was based on 10% of the lower explosive limit for safety considerations even though the relevant toxicological data indicated that irreversible health effects or impairment of escape existed only at higher concentrations (see Tables 10Athrough 10C for recommened exposure levels and IDLH limits).10 2(e)(2)(iv) American Conference of Governmental Industrial Hygienists ACGIH is an organization comprised of industrial hygienists and environmental health and safety experts. In 1941 the ACGIH the Threshold Limit Values of Chemical Substances Committee. This group was charged with investigating, recommending, and annually reviewing exposure limits for chemical substances. It became a standing committee in 1944. Two years later, the organization adopted its first list of 148 exposure limits, then referred to as Maximum Allowable Concentrations. The term “Threshold Limit Values (TLVs)” was introduced in 1956. The first Documentation of the Threshold Limit Values was published in 1962 and is now in its seventh edition. Today’s list of TLVs® includes 642 chemical substances and physical agents (Table 10A).11 2(e)(2)(v) Agency for Toxic Substances and Disease Registry The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) [42 U.S.C. 9604 et seq.], as amended by the Superfund Amendments and Reauthorization Act (SARA) [Pub. L. 99 499], requires that the Agency for Toxic Substances and Disease Registry (ATSDR) develop jointly with the U.S. Environmental Protection Agency (EPA), in order of 10 11

http://www.cdc.gov/niosh/npg/pgintrod.html#chemicalname http://www.acgih.org/about/history.htm

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priority, a list of hazardous substances most commonly found at facilities on the CERCLA National Priorities List (NPL) (42 U.S.C. 9604(i)(2)); prepare toxicological profiles for each substance included on the priority list of hazardous substances, and to ascertain significant human exposure levels (SHELs) for hazardous substances in the environment, and the associated acute, subacute, and chronic health effects (42 U.S.C. 9604(i)(3)); and assure the initiation of a research program to fill identified data needs associated with the substances (42 U.S.C. 9604(i)(5)). The ATSDR Minimal Risk Levels (MRLs) were developed as an initial response to the mandate. Following discussions with scientists within the Department of Health and Human Services (HHS) and the EPA, ATSDR chose to adopt a practice similar to that of the EPA’s Reference Dose (RfD) and Reference Concentration (RfC) for deriving substance specific health guidance levels for non neoplastic endpoints. An MRL is an estimate of the daily human exposure to a hazardous substance that is likely to be without appreciable risk of adverse noncancer health effects over a specified duration of exposure. These substance specific estimates, which are intended to serve as screening levels, are used by ATSDR health assessors and other responders to identify contaminants and potential health effects that may be of concern at hazardous waste sites. It is important to note that MRLs are not intended to define clean up or action levels for ATSDR or other Agencies (Table 10C). MRLs are intended to serve as a screening tool to help public health professionals decide where to look more closely. They may also be viewed as a mechanism to identify those hazardous waste sites that are not expected to cause adverse health effects. Most MRLs contain some degree of uncertainty because of the lack of precise toxicological information on the people who might be most sensitive (e.g., infants, elderly, and nutritionally or immunologically compromised) to effects of hazardous substances. ATSDR uses a conservative (i.e., protective) approach to address these uncertainties consistent with the public health principle of prevention. Although human data are preferred, MRLs often must be based on animal studies because relevant human studies are lacking. In the absence of evidence to the contrary, ATSDR assumes that humans are more sensitive than animals to the effects of hazardous substances that certain persons may be particularly sensitive. Thus the resulting MRL may be as much as a hundredfold below levels shown to be nontoxic in laboratory animals. Proposed MRLs undergo a rigorous review process. They are reviewed by the Health Effects/MRL Workgroup within the Division of Toxicology and Environmental Medicine; an expert panel of external peer reviewers; the agency wide MRL Workgroup, with participation from other federal agencies, including EPA; and are submitted for public comment through the toxicological profile public comment period. Each MRL is subject to change as new information becomes available concomitant with updating the toxicological profile of the substance. MRLs in the most recent toxicological profiles supersede previously published levels. To date, 130 inhalation MRLs, 219 oral MRLs and 8 external radiation MRLs have been derived. A listing of the current published MRLs by route and duration of exposure is provided in Table 10C.

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2(e)(2)(vi) World Health Organization The World Health Organization was established in 1948 as a specialized agency of the United Nations serving as the directing and coordinating authority for international health matters and public health. One of WHO’s constitutional functions is to provide objective and reliable information and advice in the field of human health, a responsibility that it fulfils in part through its publications programs. Through its publications, the Organization seeks to support national health strategies and address the most pressing public health concerns. Recognizing the need of humans for clean air, in 1987 the WHO Regional Office for Europe published Air quality guidelines for Europe (1), containing health risk assessments of different chemical air contaminants.12 2(e)(3) Safe Chemical Exposure Tables Table 6. OSHA Permissible Exposure Limits (PEL)

Chemical Name Acetaldehyde Acetic acid Acetic anhydride Acetone Acetonitrile 2-Acetylaminofluorene Acetylene tetrabromide Acrolein Acrylamide Acrylonitrile Aldrin Allyl alcohol Allyl chloride Allyl glycidyl ether Allyl propyl disulfide alpha-Alumina Total dust Respirable fraction Aluminum Metal (as Al). Total dust Respirable fraction 4-Aminodiphenyl 2-Aminopyridine Ammonia Ammonium sulfamate Total dust Respirable fraction n-Amyl acetate sec-Amyl acetate Aniline and homologs 12

http://www.euro.who.int/document/e71922.pdf

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ppm (a)(1)

mg/m3 (b)(1)

200 10 5 1000 40

360 25 20 2400 70

1 0.1

14 0.25 0.3

2 1 (C)10 2

0.25 5 3 (C)45 12

Skin designation

X X X

15 5 15 5 0.5 50

2 35

100 125 5

15 5 525 650 19

X

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Chemical Name Anisidine (o-,p-isomers) Antimony and compounds (as Sb) Naphthylthiourea Arsenic, inorganic (as As) Arsenic, organic compounds (as As) Arsine Asbestos Azinphos-methyl Barium, soluble compounds (as Ba) Barium sulfate Total dust Respirable fraction Benomyl Total dust Respirable fraction.. Benzoyl peroxide Benzyl chloride Beryllium and beryllium compounds (as Be) Bismuth telluride, Undoped Total dust Respirable fraction Boron oxide Total dust Boron trifluoride Bromine Bromoform Butadiene Methyl ethyl ketone 2-Butoxyethanol n-Butyl-acetate sec-Butyl acetate tert-Butyl-acetate n-Butyl alcohol sec-Butyl alcohol tert-Butyl alcohol Butylamine tert-Butyl chromate (as CrO(3) n-Butyl glycidyl ether (BGE) Butyl mercaptan p-tert-Butyltoluene Cadmium (as Cd) Calcium Carbonate Total dust Respirable fraction Calcium hydroxide

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ppm (a)(1)

mg/m3 (b)(1) 0.5 0.5 0.3

0.05

0.5 0.2 (4) 0.2 0.5

Skin designation X

X

15 5

1

15 5 5 5 (2) 15 5 15 (C)3 0.7 5

(C)1 0.1 0.5 1 ppm/5 ppm STEL 200 50 150 200 200 100 150 100 (C)5

590 240 710 950 950 300 450 300 (C)15

50 10 10

270 35 60

X

X

X

15 5

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Chemical Name Total dust Respirable fraction Calcium oxide Calcium silicate Total dust Respirable fraction Calcium sulfate Total dust Respirable fraction Camphor, synthetic Carbaryl (Sevin) Carbon black Carbon dioxide Carbon disulfide Carbon monoxide Carbon tetrachloride... Cellulose Total dust Respirable fraction Chlordane Chlorinated camphene Chlorinated diphenyl oxide Chlorine Chlorine dioxide Chlorine trifluoride Chloroacetaldehyde a-Chloroacetophenone (Phenacyl chloride) Chlorobenzene o-Chlorobenzylidene malononitrile Chlorobromomethane Chlorodiphenyl (42% Chlorine)(PCB) Chlorodiphenyl (54% Chlorine)(PCB) Chloroform (Trichloromethane) 1-Chloro-1-nitropropane Chloropicrin beta-Chloroprene 2-Chloro-6 (trichloromethyl) pyridine Total dust Respirable fraction Chromic acid and chromates (as CrO(3)) Chromium (II) compounds (as Cr) Chromium (III) compounds (as Cr) Chromium metal and insol. salts (as Cr) Clopidol Total dust Respirable fraction

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ppm (a)(1)

mg/m3 (b)(1)

Skin designation

15 5 5 15 5

5000 50

(C)1 0.1 (C)0.1 (C)1 0.05 75 0.05 200 (C)50 20 0.1 25

15 5 2 5 3.5 9000 (2) 55 (2) 15 5 0.5 0.5 0.5 (C)3 0.3 (C)0.4 (C)3 0.3 350 0.4 1050 1 0.5 (C)240 100 0.7 90 15 5 (2) 0.5 0.5 1 15 5

X X

X X

X

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Chemical Name Coal dust (less than 5% SiO(2)), respirable fraction Coal dust (greater than or equal to 5% SiO(2)), respirable fraction Coal tar pitch volatiles (benzene soluble fraction), anthracene, BaP, phenanthrene, acridine, chrysene, pyrene Cobalt metal, dust, and fume (as Co) Copper Fume (as Cu) Dusts and mists (as Cu) Crag herbicide (Sesone) Total dust Respirable fraction Cresol, all isomers Crotonaldehyde Cumene Cyanides (as CN) Cyclohexane Cyclohexanol Cyclohexanone Cyclohexene Cyclopentadiene 2,4-D (Dichlorophen-oxyacetic acid) Decaborane Demeton (Systox) Diacetone alcohol (4-Hydroxy-4-methyl-2pentanone) Diazomethane Diborane Dibutyl phosphate Dibutyl phthalate o-Dichlorobenzene p-Dichlorobenzene Dichlorodifluoromethane 1,3-Dichloro-5,5-dimethyl hydantoin Dichlorodiphenyltri-chloroethane (DDT) 1,1-Dichloroethane 1,2-Dichloroethylene Dichloroethyl ether Dichloromonofluoro-methane 1,1-Dichloro-1-nitroethane Dichlorotetrafluoro-ethane Dichlorvos (DDVP) Dicyclopentadienyl iron Total dust Respirable fraction

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ppm (a)(1)

mg/m3 (b)(1)

Skin designation

(3) (3) 0.2 0.1 0.1 1

5 2 50 300 50 50 300 75 0.05 50 0.2 0.1 1 (C)50 75 1000 100 200 (C)15 1000 (C)10 1000

15 5 22 6 245 5 1050 200 200 1015 200 10 0.3 0.1 240 0.4 0.1 5 5 (C)300 450 4950 0.2 1 400 790 (C)90 4200 (C)60 7000 1

X X X

X X

X X

X

15 5

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Chemical Name Dieldrin Diethylamine 2-Diethylaminoethanol Difluorodibromomethane Diglycidyl ether (DGE) Diisobutyl ketone Diisopropylamine Dimethyl acetamide Dimethylamine Dimethylaniline (N,N-Dimethylaniline) Dimethyl-1,2-dibromo-2,2-dichloroethyl phosphate Dimethylformamide 1,1-Dimethylhydrazine Dimethylphthalate Dimethyl sulfate Dinitrobenzene (all isomers) (ortho) (meta) (para) Dinitro-o-cresol Dinitrotoluene Dioxane (Diethylene dioxide) Diphenyl (Biphenyl) Dipropylene glycol methyl ether Di-sec octyl phthalate (Di-(2-ethylhexyl) phthalate) Emery Total dust Respirable fraction Endrin Epichlorohydrin EPN Ethanolamine 2-Ethoxyethanol (Cellosolve) 2-Ethoxyethyl acetate (Cellosolve acetate) Ethyl acetate Ethyl acrylate Ethyl alcohol (Ethanol) Ethylamine Ethyl amyl ketone (5-Methyl-3-heptanone) Ethyl benzene Ethyl bromide Ethyl butyl ketone (3-Heptanone) Ethyl chloride Ethyl ether Ethyl formate

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mg/m3 (b)(1)

25 10 100 (C)0.5 50 5 10 10 5

0.25 75 50 860 (C)2.8 290 20 35 18 25

10 0.5 ........ 1

100 0.2 100

3 30 1 5 5 1

0.2 1.5 360 1 600

Skin designation X X

X X X X X X X

X X X X

5

5 3 200 100 400 25 1000 10 25 100 200 50 1000 400 100

15 5 0.1 19 0.5 6 740 540 1400 100 1900 18 130 435 890 230 2600 1200 300

X X X X X X

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Chemical Name Ethyl mercaptan Ethyl silicate Ethylene chlorohydrin Ethylenediamine Ethylene dibromide Ethylene dichloride (1,2-Dichloroethane) Ethylene glycol dinitrate N-Ethylmorpholine Ferbam Total dust Ferrovanadium dust Fluorides (as F) Fluorine Fluorotrichloromethane (Trichlorofluoromethane) Formic acid Furfural Furfuryl alcohol Grain dust (oat, wheat, barley) Glycerin (mist) Total dust Respirable fraction Glycidol Graphite, natural respirable dust Graphite, synthetic Total dust Respirable Fraction Gypsum Total dust Respirable fraction Hafnium Heptachlor Heptane (n-Heptane) Hexachloroethane Hexachloronaphthalene n-Hexane 2-Hexanone (Methyl n-butyl ketone) Hexone (Methyl isobutyl ketone) sec-Hexyl acetate Hydrazine Hydrogen bromide Hydrogen chloride Hydrogen cyanide Hydrogen fluoride (as F) Hydrogen peroxide Hydrogen selenide (as Se)

Part II: Safety and Best Industry Practices

ppm (a)(1)

mg/m3 (b)(1)

(C)10 100 5 10 (C)0.2 20

(C)25 850 16 25 (2) (2) (C)1 94

0.1

15 1 2.5 0.2

1000 5 5 50

50

5600 9 20 200 10

Skin designation

X

X X

X

15 5 150 (3) 15 5

500 1 500 100 100 50 1 3 (C)5 10 1 0.05

15 5 0.5 0.5 2000 10 0.2 1800 410 410 300 1.3 10 (C)7 11 (2) 1.4 0.2

X X X

X X

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Nigerian Electricity Health and Safety Standards

Chemical Name Hydrogen sulfide Hydroquinone Iodine Iron oxide fume Isomyl acetate Isomyl alcohol (primary and secondary) Isobutyl acetate Isobutyl alcohol Isophorone Isopropyl acetate Isopropyl alcohol Isopropylamine Isopropyl ether Isopropyl glycidyl ether (IGE) Kaolin Total dust Respirable fraction Ketene Limestone Total dust Respirable fraction Lindane Lithium hydride L.P.G. (Liquified petroleum gas) Magnesite Total dust Respirable fraction.. Magnesium oxide fume Total Particulate Malathion Total dust Maleic anhydride Manganese compounds (as Mn) Manganese fume (as Mn) Marble Total dust Respirable fraction Mercury (aryl and inorganic)(as Hg) Mercury (organo) alkyl compounds (as Hg) Mercury (vapor) (as Hg) Mesityl oxide Methoxychlor Total dust 2-Methoxyethanol (Methyl cellosolve) 2-Methoxyethyl acetate (Methyl cellosolve acetate) Methyl acetate

II-96

Version 1: March 2008

ppm (a)(1)

mg/m3 (b)(1)

100 100 150 100 25 250 400 5 500 50

(2) 2 (C)1 10 525 360 700 300 140 950 980 12 2100 240

0.5

15 5 0.9

1000

15 5 0.5 0.025 1800

(C)0.1

Skin designation

X

15 5 15 0.25

15 1 (C)5 (C)5

25

15 5 (2) (2) (2) 100

25

15 80

25 200

120 610

X

X X

Version 1: March 2008

Part II: Safety and Best Industry Practices

Chemical Name

ppm (a)(1)

mg/m3 (b)(1)

Methyl acetylene (Propyne) Methyl acetylene propadiene mixture (MAPP) Methyl acrylate Methylal (Dimethoxy-methane) Methyl alcohol Methylamine Methyl n-amyl ketone Methyl bromide Methyl chloride Methyl chloroform (1,1,1-Trichloro-ethane) Methylcyclohexane Methylcyclohexanol o-Methylcyclohexanone Methylene chloride Methyl formate Methyl hydrazine (Monomethyl hydrazine) Methyl iodide Methyl isoamyl ketone Methyl isobutyl carbinol Methyl isocyanate Methyl mercaptan Methyl methacrylate alpha-Methyl styrene Methylene bisphenyl isocyanate (MDI) Molybdenum (as Mo) Soluble compounds Total dust Monomethyl aniline Morpholine Naphtha (Coal tar) Naphthalene Nickel carbonyl (as Ni) Nickel, metal and insoluble compounds (as Ni) Nickel, soluble compounds (as Ni) Nicotine Nitric acid Nitric oxide p-Nitroaniline Nitrobenzene p-Nitrochlorobenzene Nitroethane Nitrogen dioxide Nitrogen trifluoride Nitroglycerin Nitromethane 1-Nitropropane 2-Nitropropane

1000 1000 10 1000 200 10 100 (C)20

1650 1800 35 3100 260 12 465 (C)80 (2) 1900 2000 470 460 (2) 250 (C)0.35 28 475 100 0.05 (C)20 410 (C)480 (C)0.2

350 500 100 100 100 (C)0.2 5 100 25 0.02 (C)10 100 (C)100 (C)0.02

2 20 100 10 0.001

2 25 1 1 100 (C)5 10 (C)0.2 100 25 25

5 15 9 70 400 50 0.007 1 1 0.5 5 30 6 5 1 310 (C)9 29 (C)2 250 90 90

Skin designation

X

X

X X X X X

X X

X X X X

X

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Nigerian Electricity Health and Safety Standards

Version 1: March 2008

Chemical Name

ppm (a)(1)

mg/m3 (b)(1)

Nitrotoluene (all isomers) o-isomer m-isomer p-isomer Octachloronaphthalene Octane Oil mist, mineral Osmium tetroxide (as Os) Oxalic acid Oxygen difluoride Ozone Paraquat, respirable dust Parathion Particulates not otherwise regulated (PNOR)(f) Total dust Respirable fraction Pentaborane Pentachloronaphthalene Pentachlorophenol Pentaerythritol Total dust Respirable fraction Pentane 2-Pentanone (Methyl propyl ketone) Perchloroethylene (Tetrachloroethylene) Perchloromethyl mercaptan Perchloryl fluoride Petroleum distillates (Naphtha)(Rubber Solvent) Phenol p-Phenylene diamine Phenyl ether, vapor Phenyl ether-biphenyl mixture, vapor Phenyl glycidyl ether (PGE) Phenylhydrazine Phosdrin (Mevinphos) Phosgene (Carbonyl chloride) Phosphine Phosphoric acid Phosphorus (yellow) Phosphorus pentachloride Phosphorus pentasulfide Phosphorus trichloride Phthalic anhydride Picloram Total dust Respirable fraction

5

30

II-98

500

0.05 0.1

0.005

1000 200 0.1 3 500 5 1 1 10 5 0.1 0.3

0.5 2

Skin designation X

0.1 2350 5 0.002 1 0.1 0.2 0.5 0.1

X

X X

15 5 0.01 0.5 0.5

X X

15 5 2950 700 (2) 0.8 13.5 2000 19 0.1 7 7 60 22 0.1 0.4 0.4 1 0.1 1 1 3 12 15 5

X X

X X

Version 1: March 2008

Chemical Name Picric acid Pindone (2-Pivalyl-1, 3-indandione) Plaster of paris Total dust Respirable fraction Platinum (as Pt) Soluble Salts Portland cement Total dust Respirable fraction Propane n-Propyl acetate n-Propyl alcohol n-Propyl nitrate Propylene dichloride Propylene imine Propylene oxide Pyrethrum Pyridine Quinone Rhodium (as Rh), metal fume and insoluble compounds Rhodium (as Rh), soluble compounds Ronnel Rotenone Rouge Total dust Respirable fraction Selenium compounds (as Se) Selenium hexafluoride (as Se) Silica, amorphous, precipitated and gel Silica, amorphous, diatomaceous earth, containing less than 1% crystalline silica Silica, crystalline cristobalite, respirable dust Silica, crystalline quartz, respirable dust Silica, crystalline tripoli (as quartz), respirable dust Silica, crystalline tridymite, respirable dust Silica, fused, respirable dust Silicates (less than 1% crystalline silica) Mica (respirable dust) Soapstone, total dust Soapstone, respirable dust Talc (containing no asbestos), respirable dust Silicon Total dust Respirable fraction

Part II: Safety and Best Industry Practices

ppm (a)(1)

mg/m3 (b)(1) 0.1 0.1

Skin designation X

15 5 0.002

1000 200 200 25 75 2 100 5 0.1

15 5 1800 840 500 110 350 5 240 5 15 0.4

X

0.1 0.001 15 5

0.05

15 5 0.2 0.4 (3) (3) (3) (3) (3) (3) (3) (3) (3) (3) (3) 15 5

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Nigerian Electricity Health and Safety Standards

Chemical Name Silicon carbide Total dust Respirable fraction Silver, metal and soluble compounds (as Ag) Sodium fluoroacetate Sodium hydroxide Starch Total dust Respirable fraction Stibine Stoddard solvent Strychnine Styrene Sucrose Total dust Respirable fraction Sulfur dioxide Sulfur hexafluoride Sulfuric acid Sulfur monochloride Sulfur pentafluoride Sulfuryl fluoride 2,4,5-T (2,4,5-tri- chlorophenoxyacetic acid) Tantalum, metal and oxide dust. TEDP (Sulfotep) Tellurium and compounds (as Te) Tellurium hexafluoride (as Te) Temephos Total dust Respirable fraction.. TEPP (Tetraethyl pyrophosphaate) Terphenylis 1,1,1,2-Tetrachloro-2, 2-difluoroethane 1,1,2,2-Tetrachloro-1, 2-difluoroethane 1,1,2,2-Tetrachloro-ethane Tetrachloronaphthalene. Tetraethyl lead (as Pb) Tetrahydrofuran Tetramethyl lead, (as Pb) Tetramethyl succinonitrile Tetranitromethane Tetryl (2,4,6-Trinitro-phenylmethyl-nitramine) Thallium, soluble compounds (as Tl) 4,4'-Thiobis(6-tert, Butyl-m-cresol) Total dust Respirable fraction Thiram

II-100

Version 1: March 2008

ppm (a)(1)

mg/m3 (b)(1) 15 5 0.01 0.05 2

0.1 500

5 1000 1 0.025 5

0.02

(C)1 500 500 5 200 0.5 1

Skin designation

X

15 5 0.5 2900 0.15 (2) 15 5 13 6000 1 6 0.25 20 10 5 0.2 0.1 0.2 15 5 0.05 (C)9 4170 4170 35 2 0.075 590 0.075 3 8 1.5 0.1 15 5 5

X

X

X X X X X X X

Version 1: March 2008

Chemical Name Tin, inorganic compounds (except oxides) (as Sn) Tin, organic compounds (as Sn) Titanium dioxide Total dust Toluene Toluene-2,4-diisocyanate (TDI) o-Toluidine Tributyl phosphate 1,1,2-Trichloroethane Trichloroethylene Trichloronaphthalene 1,2,3-Trichloropropane 1,1,2-Trichloro-1,2,2-trifluoroethane Triethylamine Trifluorobromomethane 2,4,6-Trinitrotoluene (TNT) Triorthocresyl phosphate Triphenyl phosphate Turpentine Uranium (as U) Soluble compounds Insoluble compounds Vanadium Respirable dust (as V2O5) Fume (as V2O5) Vegetable oil mist Total dust Respirable fraction Vinyl toluene Warfarin Xylenes (o-, m-, p-isomers) Xylidine Yttrium Zinc chloride fume Zinc oxide fume Zinc oxide Total dust Respirable fraction Zinc stearate Total dust Respirable fraction.. Zirconium compounds (as Zr)

Part II: Safety and Best Industry Practices

ppm (a)(1)

mg/m3 (b)(1)

Skin designation

2 0.1

(C)0.02 5 10 50 1000 25 1000

100

15 (2) (C)0.14 22 5 45 (2) 5 300 7600 100 6100 1.5 0.1 3 560

X X X

X

0.05 0.25 (C)0.5 (C)0.1

100 100 5

15 5 480 0.1 435 25 1 1 5

X

15 5 15 5 5

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Nigerian Electricity Health and Safety Standards

Version 1: March 2008

Skin designation 29 CFR Part Number: 1910 Part Title: Occupational Safety and Health Standards Subpart: Z Subpart Title: Toxic and Hazardous Substances, Standard Number: 1910.1000 TABLE Z-1, Title: TABLE Z-1 Limits for Air Contaminants. Available HTTP://www.osha.gov/pls/oshaweb/owadisp.show_document? p_table=STANDARDS&p_id=9992 Chemical Name

II-102

ppm (a)(1)

mg/m3 (b)(1)

Version 1: March 2008

Part II: Safety and Best Industry Practices

Table 7. OSHA Permissible Exposure Limits (PEL) Time Weighted Averages

Substance Benzene(a) Beryllium and beryllium compounds Cadmium fume(b) Cadmium dust(b) Carbon disulfide Carbon tetrachloride Chromic acid and chromates Ethylene dibromide Ethylene dichloride Fluoride as dust Formaldehyde Hydrogen fluoride

8-hour TWA

Acceptable ceiling concentration

10 ppm

25 ppm

Acceptable maximum peak above the acceptable ceiling concentration for an 8-hr shift 50 ppm

2 ug/m(3)

5 ug/m(3)

25 ug/m(3)

30 minutes.

0.1 mg/m(3) 0.2 mg/m(3) 20 ppm 10 ppm

0.3 mg/m(3) 0.6 mg/m(3) 30 ppm 25 ppm 1 mg/10 m(3) 30 ppm 100 ppm

100 ppm 200 ppm

30 minutes. 5 min. in any 3 hrs.

50 ppm 200 ppm

5 minutes. 5 min. in any 3 hrs.

20 ppm

50 ppm

10 mins. once only if no other meas. exp. occurs.

100 ppm

1 mg/10m(3) 200 ppm

300 ppm

5 mins. in any 3 hrs.

0.01mg/m(3) 100 ppm 100 ppm 200 ppm 100 ppm

0.04 mg/m(3) 200 ppm 200 ppm 300 ppm 200 ppm

600 ppm 300 ppm 500 ppm 300 ppm

5 mins. in any 3 hrs. 5 mins. in any 3 hrs. 10 minutes 5 mins. in any 2 hrs.

20 ppm 50 ppm 2.5 mg/m(3)

10 minutes.

3 ppm

Hydrogen sulfide Mercury Methyl chloride Methylene Chloride Organo (alkyl) mercury Styrene Tetrachloroethylene Toluene Trichloroethylene

Maximum duration

29 CFR Part Number: 1910 Part Title: Occupational Safety and Health Standards Subpart: Z Subpart Title: Toxic and Hazardous Substances Standard Number: 1910.1000 TABLE Z-2 Title: TABLE Z-2. Available HTTP://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table= STANDARDS&p_id=9993

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Nigerian Electricity Health and Safety Standards

Version 1: March 2008

Table 8. OSHA IDLH

IDLH ppm

STEL/Ceiling Ppm

Acetaldehyde Acetic Acid Acetic Anhydride Acetone Acetonitrile Acetylene tetrabromide Acrolein Acrylamide Aldrin Allyl alcohol Allyl chloride Allyl glycidyl ether Allyl propyl disulfide 2-Aminopyridine Ammonia Ammonium sulfamate (td) n-Amyl acetate sec-Amyl acetate Aniline and homologs Anisidine o-, p-isomers Antimony & compounds ANTU Arsine Azinphos-methyl Benzoyl peroxide Benzyl chloride Boron oxide (td) Boron trifluoride Bromine Bromoform 1,3 Butadiene 2-Butanone (MEK) 2-Butoxyethanol n-Butyl-acetate sec-Butyl acetate tert-Butly acetate n-Butyl alcohol sec-Butyl alcohol tert-Butyl alcohol Butylamine tert-Butyl chromate n-Butyl glycidyl ether Butyl mercaptan p-tert-Butyl-1-toluene

2000 ++ 50 200 2500 500 8 2 60 mg/m3++ 25 mg/m3++ 20 250 50

25 + 15

Calcium oxide Camphor, synthetic Carbaryl Carbon black Carbon dioxide Carbon Disulfide Carbon monoxide

25 mg/m3 200 mg/m3 100 mg/m3 1750 mg/m3 40,000 500 1200

Chemical Name

II-104

5 300 1500 mg/m3 1000 1000 100 ++ 50 mg/m3 50 mg/m3 100 mg/m3 3 ++ 10 mg/m3 1500 mg/m3 10 2000 mg/m3 25 3 850 2000 ++ 3000 700 1700 1700 1500 1400 2000 1600 300 15 mg/m3 250 500 100

1000 60 0.3

4 2 10 + 3 35

1+ 0.2

300 200

50 +

5+ 0.1 mg/m3+

19 mg/m3+

30,000

Version 1: March 2008

Chemical Name Chlorodane Chlorinated camphene Chlorinated diphenyl oxide Chlorine Chlorine dioxide Chlorine trifluoride Chloroacetaldehyde a-chloroacetophenone Chlorobenzene o-Chlorobenzylidene malononitrile Chlorobromomethane Chlorodiphenyl (42% Cl) Chlorobiphenyl (54% Cl) 1-Chloro-1-nitro- propane Chloropicrin beta-Chloroprene 2-Chloro-6-trichloro- methyl) pyridine (td) Chromium (II) compounds Chromium (III) compounds Chromium metal and insoluble salts Coal tar pitch volatiles Cobalt metal, dust, and fume Copper fume Copper dusts and mists Cotton dust Crag herbicide (td) Cresol, all isomers Crotonaldehyde Cumene Cyclohexane Cyclohexanol Cyclohexanone Cyclohexene Cyclopentadiene 2,4-D Decaborane Demeton Diacetone alcohol Diazomethane Diborane Dibutyl phosphate Dibutyl phthalate o-Dichlorobenzene p-Dichlorobenzene 1,1Dichloroethane 1,2-Dichloroethylene Dichloroethyl ether Dichloromono- fluomethane 1,1 Dichloro-1- nitroethane Dichlorotetra- fluoroethane Dichlorvos (DDVP) Dieldrin

Part II: Safety and Best Industry Practices IDLH ppm 100 mg/m3++ 200 mg/m3CA 5 mg/m3 10 5 20 45 15 mg/m3 1000 2 mg/m3 2000 5 mg/m3++ 5 mg/m3++ 100 2 300

STEL/Ceiling Ppm

1 0.3 0.1 + 1+

0.05 +

20 mg/m3 250 mg/m3 25 mg/m3 250 mg/m3 80 mg/m3++ 20 mg/m3 100 mg/m3 100 mg/m3 100 mg/m3 500 mg/m3 250 50 900 1300 400 700 2000 750 100 mg/m3 15 mg/m3 10 V 1800 2 15 30 4000 mg/m3 200 150 ++ 3000 1000 100 ++ 5000 25 15,000 100 mg/m3 50 mg/m3++

0.15

2

15 10 +

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Nigerian Electricity Health and Safety Standards

Version 1: March 2008

Chemical Name

IDLH ppm

STEL/Ceiling Ppm

Diethylamine 2-Diethylaminoethanol Difluorodibromomethane Diglycidyl ether (DGE) Diisobutyl ketone Diisopropylamine Dimethyl acetamide Dimethylamine Dimethylaniline (N,N-Dimethylaniline) Dimethyl-1,2-dibromo- 2,2-dichloroethyl phosphate Dimethylformamide 1,1-Dimethylhydrazine Dimethylphthalate Dimethyl sulfate Dinitrobenzene (all isomers) Dinitro-o-cresol Dinitrotoluene Dioxane (Diethylene dioxide) Diphenyl (Biphenyl) Dipropylene glycol methyl ether Di-sec octyl phthalate (Di-(2-ethylhexyl) phthalate) Endrin Epichlorohydrin EPN Ethanolamine 2-Ethoxyethanol (Cellosolve) 2-Ethoxyethyl acetate (cellosolve acetate) Ethyl acetate Ethyl acrylate Ethyl alcohol (Ethanol) Ethylamine Ethyl benzene Ethyl bromide Ethyl butyl ketone (3- Heptanone) Ethyl chloride Ethylene chlorohydrin Ethylene glycol dinitrate Ethyl ether Ethyl formate Ethyl mercaptan Ethyl silicate Ethylenediamine N-Ethylmorpholine Ferbam (td) Ferrovanadium dust Fluorine Fluorotrichloromethane (Trichlorofluoromethane) Formic acid Furfural Furfuryl alcohol Glycidol Hafnium

200 100 2000 10 ++ 500 200 300 500 100 200 mg/m3 500 15++ 2000 mg/m3 7++ 50 mg/m3 5 mg/m3 50 mg/m3++ 500++ 100 mg/m3 600 10 mg/m3 + 2 mg/m3 75++ 5 mg/m3 30 500 500 2000 300 3300 600 800 2000 1000 3800 7 75 mg/m3 1900 1500 500 700 1000 100 800 mg/m3 500 mg/m3 25 2000 30 100 75 150 50 mg/m3

15

II-106

0.5 +

15 10

150

6

15 15 125

0.2+ 500 10+

3 mg/m3 + 2 1000+ 10 15

Version 1: March 2008

Chemical Name

Part II: Safety and Best Industry Practices IDLH ppm

Heptachlor Heptane (n-Heptane) Hexachloroethane Hexachloronaph- thalene n-Hexane 2-Hexanone (Methyl n-butyl ketone) Hexone (Methyl isobutyl ketone) sec-Hexyl acetate Hydrazine Hydrogen bromide Hydrogen chloride Hydrogen cyanide Hydrogen peroxide Hydrogen selenide (as Se) Hydroquinone Iodine Iron oxide fume Isoamyl acetate

35 mg/m3 ++ 750 300++ 2 mg/m3 1100 1600 500 500 50 30 50 50 75 1 50 mg/m3 2 2500 mg/m3 1000

Isoamyl alcohol (primary and secondary) Isobutyl acetate Isobutyl alcohol Isophorone Isopropyl acetate Isopropyl alcohol Isopropylamine Isopropyl ether Isopropyl glycidyl ether (IGE) Ketene Lindane Lithium hydride L.P.G. (Liquefied petroleum gas) Magnesium oxide fume (total particulate) Malathion (td) Maleic anhydride Manganese compounds (as Mn) Manganese fume (as Mn) Mesityl oxide Methoxychlor (td) 2-Methoxyethanol (Methyl cellosolve)

500 1300 1600 200 1800 2000 750 1400 400 5 50 mg/m3 0.5 mg/m3 2000 750 mg/m3 250 mg/m3 10 mg/m3 500 mg/m3 500 mg/m3 1400 5000 mg/m3+ 200

2-Methoxyethyl acetate (Methyl cellosolve acetate) Methyl acetate Methyl acetylene (propyne) Methyl acetylene- propadiene mixture (MAPP) Methyl acrylate Methylal (Dimetoxy- methane) Methyl alcohol Methylamine Methyl n-amyl ketone Methyl bromide Methyl chloroform (1,1,1- Trichloroethane)

200 3100 1700 3400 250 2200 6000 100 800 250++ 700

STEL/Ceiling Ppm 500

75

3+ 5+ 4.7+

0.1+

125

5+ 310 500 10 310 75 1.5

5 mg/m3+ 5 mg/m3+ 25

250 1250

250 15 20+ 450

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Nigerian Electricity Health and Safety Standards

Chemical Name Methylcyclohexane Methylcyclohexanol o-Methylcyclohexanone Methylene bisphenyl isocyanate (MDI) Methyl formate Methyl hydrazine (Mono- methyl hydrazine) Methyl iodide Methyl isobutyl carbinol Methyl isocyanate Methyl mercaptan Methyl methacrylate alpha-Methyl styrene Molybdenum (as Mo) Soluble compounds Molybdenum (as Mo) Insoluble compounds (td) Monomethyl aniline Morpholine Naphtha (Coal tar) Naphthalene Nickel carbonyl (as Ni) Nickel, metal and insoluble compounds (as Ni) Nicotine Nitric acid Nitric oxide p-Nitroaniline Nitrobenzene p-Nitrochlorobenzene Nitroethane Nitrogen dioxide Nitrogen trifluoride Nitroglycerin Nitromethane 1-Nitropropane 2-Nitropropane Nitrotoluene (all isomers) Octachloronaphthalene Octane Oil mist, mineral Osmium tetroxide (as Os) Oxalic acid Oxygen difluoride Ozone Paraquat (rd) Parathion Pentaborane Pentachloronaphthalene Pentachlorophenol Pentane 2-Pentanone (Methyl propyl ketone) Perchloromethyl mercaptan Perchloryl fluoride Petroleum distillates (Naphtha) (Rubber Solvent) Phenol

II-108

IDLH ppm 1200 500 600 75 mg/m3 4500 20++ 100++ 400 3 150 1000 700 1000 mg/m3 5000 mg/m3 100 1400 1000 250 2++ 10 mg/m3++ 5 mg/m3 25 100 300 mg/m3 200 100 mg/m3+ 1000 20 1000 75 mg/m3 750 1000 100 200 Unknown 1000 2500 mg/m3 1 mg/m3 500 mg/m3 0.5 5 1 mg/m3 10 mg/m3 1 Unknown 2.5 mg/m3 1500 1500 10 100 1100 250

Version 1: March 2008 STEL/Ceiling Ppm 75 0.02+ 150 0.2+ 40 10+ 100+

15

4

5 0.2+

0.3 mg/m3+ 375 10 mg/m3 0.0006 2 mg/m3 0.05+ 0.1+

0.015

750 250 25+ 1480

Version 1: March 2008

Chemical Name p-Phenylene diamine Phenyl ether, vapor Phenyl ether-biphenyl mixture, vapor Phenyl glycidyl ether (PGE) Phenylhydrazine Phosdrin (mevinphos) Phosgene (Carbonyl chloride) Phosphine Phosphoric acid Phosphorus (yellow) Phosphorus pentachloride Phosphorus pentasulfide Phosphorus trichloride Phthalic anhydride Picric acid Pindone (2-Pivalyl-1, 3-indandione) Platinum (as Pt) Soluble salts Portland cement (td) Propane n-Propyl acetate n-Propyl alcohol Propylene dichloride Propylene imine Propylene oxide n-Propyl nitrate Pyrethrum Pyridine Quinone Rhodium, metal fume and insoluble compounds Rhodium, soluble compounds Ronnel Rotenone Selenium compounds (as Se) Selenium hexafluoride (as Se) Silver, metal and soluble compounds (as Ag) Sodium fluoro- acetate Sodium hydroxide Stibine Stoddard solvent Strychnine Sulfur dioxide Sulfuric acid Sulfur monochloride Sulfur pentafluoride Sulfuryl fluoride 2,4,5-T (2,4,5-trichloro- phenoxyacetic acid) Tantalum, metal and oxide dust TEDP (Sulfotep) Tellurium and com- pounds (as Te) Tellurium hexafluoride (as Te) TEPP (Tetraethyl pyrophosphate) Terphenyls

Part II: Safety and Best Industry Practices IDLH ppm 25 mg/m3 100 10 100++ 15++ 4 2 50 1000 mg/m3 5 mg/m3 70 mg/m3 250 mg/m3 25 60 mg/m3 75 mg/m3 100 mg/m3 4 mg/m3 5000 mg/m3 2100 1700 800 400++ 100++ 400++ 500 5000 mg/m3 1000 100 mg/m3 100 mg/m3 2 mg/m3 300 mg/m3 2500 mg/m3 1 mg/m3 2 10 mg/m3 2.5 mg/m3 10 mg/m3 5 20,000 mg/m3 3 mg/m3 100 15 mg/m3 5 1 200 250 mg/m3 2500 mg/m3 10 mg/m3 25 mg/m3 1 5 mg/m3 500 mg/m3

STEL/Ceiling Ppm 2

0.03 1

3 mg/m3 0.5

250 250 110

40

2 mg/m3+

5 3 mg/m3+ 1+ 0.01+ 10

1

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Nigerian Electricity Health and Safety Standards

Chemical Name

IDLH ppm

1,1,1,2-Tetrachloro-2, 2-difluoroethane 1,1,2,2-Tetrachloro-1, 2-difluoroethane 1,1,2,2-Tetrachlo- roethane Tetrachloronaph- thalene Tetraethyl lead (as Pb) Tetrahydrofuran Tetramethyl lead (as Pb) Tetramethyl succinonitrile Tetranitromethane Tetryl (2,4,6-Trinitro- phenylmethylni- tramine) Thallium, soluble compounds (as Tl) Thiram Tin, inorganic compounds (except oxides) (as Sn) Tin, organic com-| pounds (as Sn) Titanium dioxide (td) Toluene-2,4- diisocyanate (TDI) o-Toluidine Tributyl phosphate 1,1,2-Trichloroethane Trichloronaphthalene 1,2,3-Trichloropropane 1,1,2-Trichloro-1,2,2- trifluoroethane Triethylamine Trifluorobromo- methane 2,4,6-Trinitrotoluene (TNT) Triorthocresyl phosphate Triphenyl phosphate Turpentine Uranium (as U) Soluble compounds Uranium (as U) Insoluble compounds Vanadium (rd) (as V2O5) Vanadium (fume) (as V2O5) Vinyl toluene Warfarin Xylenes (o-, m-, p-isomers) Xylidine Yttrium Zinc chloride fume Zinc oxide fume Zinc oxide (td) Zinc oxide (rf)

2000 2000 100++ Unknown 40 mg/m3 2000 40 mg/m3 5 4 750 mg/m3 15 mg/m3 100 mg/m3 100 mg/m3 25 mg/m3 5000 mg/m3+ 2.5++ 50++ 30 100++ Unknown 100++ 2000 200 40,000 500 mg/m3 40 mg/m3 1000 mg/m3 800 10 mg/m3++ 10 mg/m3++ 35 mg/m3 35 mg/m3 400 100 mg/m3 900 50 500 mg/m3 50 mg/m3 500 mg/m3 500 mg/m3 500 mg/m3

Zirconium compounds (as Zr)

50 mg/m3

Version 1: March 2008 STEL/Ceiling Ppm

250

0.02+

1250 3

0.5 mg/m3 0.1 mg/m3 100 150

10 mg/m3

" + " indicates a Ceiling Value " ++ " indicates that the chemical is believed, by NIOSH, to be a potential Carcinogen. **Reference: http://www.labsafety.com/refinfo/ezfacts/ezf232.htm

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Part II: Safety and Best Industry Practices

Table 9. NIOSH Recommended Exposure Limits (REL) CHEMICAL NAME AA 2-AAF AAF Abate® Acetaldehyde Acetic acid Acetic anhydride Acetone Acetone cyanohydrin Acetonitrile 2-Acetylaminofluorene Acetylene Acetylene tetrabromide Acetylsalicyclic acid Acrolein Acrylamide Acrylic acid Acrylonitrile

NIOSH REL TWA (ppm)

NIOSH REL TWA (mg/m3)

2 (skin)

5 (skin)

NIOSH Ceiling REL (ppm)

NIOSH Ceiling REL (mg/m3)

NIOSH REL STEL (ppm)

NIOSH REL STEL (mg/m3)

4 (skin)

10 (skin)

15

37

0.3

0.8

10 (total) 5 (resp) 10 5 250

25 20 590

20

34

0.1 2 (skin)

4 (15 min)

2500

2662

5 0.25 0.03 (skin) 6 (skin) 10 (15min/skin)

1 (15min/skin)

3-(alpha-Acetonyl) -benzyl-4-hydroxycoumarin 2-Acetoxybenzoic acid o-Acetoxybenzoic acid 1-Acetoxyethylene 2-Acetylaminofluorene N-Acetyl-2-aminofluorene

1 (15min)

0.1 5 5 4 (15min)

15 (15min)

5

20

3.5 (0.1 mg PAHs/m3)

Acetylene black Acetylene dichloride

200

790

cis-Acetylene dichloride

200

790

trans-Acetylene dichloride

200

790

Acetylene tetrabromide Acetylene tetrachloride

1 (skin)

7 (skin)

Acetyl mercaptan

1 (skin)

4 (skin)

Acetyl oxide

II-111

Nigerian Electricity Health and Safety Standards

CHEMICAL NAME 2-Acetyl propane Acetylsalicyclic acid Acheson graphite Acraldehyde

NIOSH REL TWA (ppm)

NIOSH REL TWA (mg/m3)

200

705 5

0.1

0.25

2 (skin) 0.1 0.1

2 (skin) 0.1

Acrylonitrile

1 (15min/skin)

Acrylonitrile monomer

1 (15min/skin)

Actinolite Actinolite asbestos Adiponitrile AGE Alcohol Aldrin Aliphatic petroleum naphtha Allyl alcohol Allyl aldehyde Allyl chloride Allylene Allyl glycidyl ether Allylic alcohol 1-Allyloxy-2, 3-epoxypropane Allyl propyl disulfide Allyl trichloride alpha-Alumina

II-112

NIOSH Ceiling REL (ppm)

NIOSH Ceiling REL (mg/m3)

NIOSH REL STEL (ppm)

NIOSH REL STEL (mg/m3)

0.3

0.8

0.3 0.3

0.8 0.8

0.3

0.8

10 (skin)

44 (skin)

4 (skin) 0.3 2

10 (skin) 0.8 6

10 (skin) 4 (skin) 10 (skin) 3

44 (skin) 10 (skin) 44 (skin) 18

0.1 (cyclohexaneextractable)

Acridine Acroleic acid Acrolein Acrylaldehyde Acrylamide Acrylamide monomer Acrylic acid Acrylic aldehyde Acrylic amide

Version 1: March 2008

4 5 (skin) 1000

2 (skin) 0.1 1 1000 5 (skin) 2 (skin) 5 (skin) 2 10 (skin)

6 (skin) 0.25 0.25 0.03 (skin) 0.03 (skin) 6 (skin) 0.25 0.03 (skin) 10 (15min/skin) 10 (15min/skin)

18 22 (skin) 1900 0.25(skin) 350 (15min) 5 (skin) 0.25 3 1650 22 (skin) 5 (skin) 22 (skin) 12 60 (skin)

1800 (15min)

Version 1: March 2008

CHEMICAL NAME

Part II: Safety and Best Industry Practices NIOSH REL TWA (ppm)

NIOSH REL TWA (mg/m3)

NIOSH Ceiling REL (ppm)

NIOSH Ceiling REL (mg/m3)

5 (skin)

15 (skin)

NIOSH REL STEL (ppm)

NIOSH REL STEL (mg/m3)

0.66 (vapor)

3 (dust) 3 (vapor)

0.66 (vapor)

3 (dust) 3 (vapor)

Alumina Aluminum

10 (total) 5 (resp)

Aluminum metal

10 (total) 5 (resp)

Aluminum oxide Aluminum oxide Aluminum powder

10 (total) 5 (resp)

Aluminum (pyro powders and welding fumes, as Al) Aluminum (soluble salts and alkyls, as Al) Aluminum trioxide Aluminum trioxide Amidocyanogen 4-Aminoaniline ortho-Aminoanisole para-Aminoanisole Aminobenzene 4-Aminobiphenyl p-Aminobiphenyl 1-Aminobutane Aminocaproic lactam Aminocyclohexane Aminodimethylbenzene

5 2

2 0.1 (skin) 0.5 (skin) 0.5 (skin)

0.22 (vapor)

1 (dust) 1 (vapor)

10 2 (skin)

40 10 (skin)

4-Amino-6-(1, 1-dimethylethyl) -3-(methylthio) -1, 2, 4-triazin-5(4H) -one

5

4-Aminodiphenyl p-Aminodiphenyl 1-Aminobutane Aminocaproic lactam Aminocyclohexane Aminodimethylbenzene

5 (skin) 0.22 (vapor)

1 (dust) 1 (vapor)

10 2 (skin)

40 10 (skin)

15 (skin)

II-113

Nigerian Electricity Health and Safety Standards

CHEMICAL NAME

NIOSH REL TWA (ppm)

4-Amino-6-(1, 1-dimethylethyl) -3-(methylthio) -1, 2, 4-triazin-5(4H) -one 4-Aminodiphenyl p-Aminodiphenyl Aminoethane 2-Aminoethanol beta-Aminoethyl alcohol bis(2-Aminoethyl) amine Aminoethylene N-(2-Aminoethyl)-1, 2-ethanediamine Aminohexahydrobenzene Aminomethane 1, 3-bis(Aminomethyl) benzene 3-Amino-1-methylbenzene 1-Aminonaphthalene 2-Aminonaphthalene para-Aminonitrobenzene 1-Aminophenylmethane 2-Aminopropane 2-Aminopyridine alpha-Aminopyridine 2-Aminotoluene 4-Aminotoluene m-Aminotoluene o-Aminotoluene 2-Amino-1, 3, 4-triazole 3-Amino-1, 2, 4-triazole 3-Aminotriazole Aminotriazole 4-Amino-3, 5, 6-trichloro-2-picolinic acid 4-Amino-3, 5, 6-trichloropicolinic acid Aminoxylene Amitrole Ammate herbicide

II-114

Version 1: March 2008 NIOSH REL TWA (mg/m3)

NIOSH Ceiling REL (ppm)

NIOSH Ceiling REL (mg/m3)

NIOSH REL STEL (ppm)

NIOSH REL STEL (mg/m3)

6 6

15 15

5

10 3 3 1 (skin)

18 8 8 4 (skin)

1 (skin) 10 10

4 (skin) 40 12 0.1 (skin)

3 (skin)

0.5 0.5

2 2

0.2 0.2 0.2 0.2

2 (skin)

10 (skin) 0.2 10 (total) 5 (resp)

Version 1: March 2008

CHEMICAL NAME Ammonia

Part II: Safety and Best Industry Practices NIOSH REL TWA (ppm)

NIOSH REL TWA (mg/m3)

25

18

Ammonium amidosulfonate

Anhydrous ammonia Anhydrous borax

50

27

100

485

35

27

10 (total) 5 (resp) 100 125 100 100 50 25

100 100

525 650 525 525 175 130

1 (15min/skin) 25

2.1 (15min) 2.1 (15min)

0.5 (15min) 10 (15min/skin)

2.1 (15min)

18 1

Anhydrous gypsum

10 (total) 5 (resp)

3 (15min)

0.5 (15min) 0.5 (15min) 465 465

10 (total) 5 (resp)

Anhydrous sulfate of lime

35

20 20 20

240

Anhydrous calcium sulfate

Anhydrous hydrogen bromide Anhydrous hydrogen chloride Anhydrous hydrogen fluoride

NIOSH REL STEL (mg/m3)

10 (total) 5 (resp)

AMS

AN

NIOSH REL STEL (ppm)

10 10 10

Ammonium sulfamate

n-Amyl acetate sec-Amyl acetate Amyl acetic ester Amyl acetic ether Amyl aldehyde Amyl ethyl ketone Amyl hydrosulfide Amyl mercaptan Amyl methyl ketone n-Amyl methyl ketone Amyl sulfhydrate

NIOSH Ceiling REL (mg/m3)

10 (total) 5 (resp)

Ammonium chloride Ammonium chloride fume Ammonium muriate fume

Amosite (cummingtonite-grunerite) AMS

NIOSH Ceiling REL (ppm)

2.5 (15min)

3 5 6 (15min)

10 7 5 (15min)

10 (total) 5 (resp)

II-115

Nigerian Electricity Health and Safety Standards

CHEMICAL NAME Aniline (and homologs) Aniline oil Anilinobenzene 2-Anilinonaphthalene 2-Anisidine 4-Anisidine o-Anisidine p-Anisidine Anol Anone Antabuse® Anthophyllite Anthophyllite asbestos Anthracene & benzo(a) pyrene) . Anthracite coal dust Antimony Antimony hydride Antimony metal Antimony powder Antimony trihydride ANTU Aprocarb® Aqua ammonia Aqua fortis Aqueous acrylic acid (technical grade is 94%) Aqueous ammonia Aqueous hydrogen bromide (i.e., Hydrobromic acid)

NIOSH REL TWA (ppm)

Version 1: March 2008 NIOSH REL TWA (mg/m3)

II-116

NIOSH Ceiling REL (mg/m3)

NIOSH REL STEL (ppm)

NIOSH REL STEL (mg/m3)

35 4

27 10

35

27

10

50 (skin) 25 (skin)

0.5 (skin) 0.5 (skin) 0.5 (skin) 0.5 (skin) 200 (skin) 100 (skin) 2

0.1

0.1

0.1

25 2 2 (skin) 25

0.5 0.5 0.5 0.5 0.5 0.3 0.5 18 5 6 (skin) 18

Aqueous hydrogen chloride (i.e., Hydrochloric acid, Muriatic acid) Aqueous hydrogen fluoride (i.e., Hydrofluoric acid) Aroclor® 1242 Aroclor® 1254 Arsenic hydride Arsenic (inorganic compounds, as As) Arsenic metal: Arsenia

NIOSH Ceiling REL (ppm)

3 (15min)

2.5 (15min) 0.001 0.001

3

10

5

7

6 (15min)

5 (15min)

0.002 (15min) 0.002 (15min) 0.002 (15min)

Version 1: March 2008

CHEMICAL NAME

Part II: Safety and Best Industry Practices NIOSH REL TWA (ppm)

NIOSH REL TWA (mg/m3)

NIOSH Ceiling REL (ppm)

Arsenic, organic compounds (as As) Arsenic trihydride Arseniuretted hydrogen Arsenous hydride Arsine

5 (15min) 5 mg/m3 (15min)

Asphalt fumes

5 25 100

125 400

5

5 0.1 15 0.1 (as HN3 on skin)

Azide 0.2 5

Barium sulfate

0.3 (as NaN3 on skin)

0.4 15 0.2 (skin)

0.1 (as HN3 on skin)

Azium Azomethylene Azophos® Barium chloride (as Ba) Barium nitrate (as Ba)

NIOSH REL STEL (mg/m3)

10 (total) 5 (resp)

Arificial graphite Asbestos Asphalt: Asphaltum

Azimethylene Azine Azinphos-methyl Azirane Aziridine

NIOSH REL STEL (ppm)

0.002 (15min) 0.002 (15min) 0.002 (15min) 0.002 (15min)

Artificial barite

Aspirin Asymmetrical trimethylbenzene Asymmetrical dichloroethane ATCP Atrazine Aurum paradoxum Azabenzene

NIOSH Ceiling REL (mg/m3)

0.2

0.3 (as NaN3 on skin)

0.4 0.2 (skin) 0.5 0.5 10 (total) 5 (resp)

II-117

Nigerian Electricity Health and Safety Standards

CHEMICAL NAME

NIOSH REL TWA (ppm)

Benomyl Benzene Benzenethiol Benzidine Benzoyl peroxide Benzyl chloride

NIOSH Ceiling REL (ppm)

NIOSH Ceiling REL (mg/m3)

.1 (15min)

0.5 (15min)

1 (15min)

5 (15min)

1 1

10 3

0.1

NIOSH REL STEL (ppm)

NIOSH REL STEL (mg/m3)

1

5 not to exceed 0.0005

Bismuth telluride, doped with Selenium sulfide (as Bi2Te3)

5

Bismuth telluride, undoped

II-118

NIOSH REL TWA (mg/m3) 15 (total) 5 (resp)

Beryllium & beryllium compounds (as Be)

Borates, tetra, sodium salts (Anhydrous) Borates, tetra, sodium salts (Decahydrate) Borates, tetra, sodium salts (Pentahydrate) Boron oxide Boron tribromide Boron trifluoride Bromacil Bromine Bromine pentafluoride Bromoform 1, 3-Butadiene n-Butane 2-Butanone 2-Butoxyethanol 2-Butoxyethanol acetate n-Butyl acetate sec-Butyl acetate tert-Butyl acetate Butyl acrylate n-Butyl alcohol sec-Butyl alcohol tert-Butyl alcohol

Version 1: March 2008

10 (total) 5 (resp) 1 5 1 10

1 0.1 0.1 0.5 (skin)

10 0.7 0.7 5 (skin)

800 200 5 (skin) 5 150 200 200 10

1900 590 24 (skin) 33 710 950 950 55

100 100

305 300

50 (skin)

0.3

2

300

885

200

950

150 150

455 450

150 (skin)

Version 1: March 2008

CHEMICAL NAME

Part II: Safety and Best Industry Practices NIOSH REL TWA (ppm)

NIOSH REL TWA (mg/m3)

n-Butylamine

5

25

5 (skin) 10 8

30 (skin) 60 22

Calcium carbonate

10 (total) 5 (resp)

Calcium cyanamide Calcium hydroxide Calcium oxide

0.5 5 2

Calcium silicate

10 (total) 5 (resp)

Calcium sulfate

10 (total) 5 (resp)

Camphor (synthetic)

15 (skin)

5.6 (15min)

30 (15min)

0.5 (15min)

1.8 (15min)

NIOSH REL STEL (mg/m3)

20

120

0.66 (vapor)

3 (dust) 3 (vapor)

30000 10 (skin)

54000 30 (skin)

2 0.22 (vapor)

Captafol Captan Carbaryl Carbofuran

1 (dust) 1 (vapor) 0.1 (skin) 5 5 0.1 3.5 (0.1 mg PAHs/m3…carbon black in the presence of PAHs)

Carbon black

Carbon dioxide Carbon disulfide

5 (skin)

NIOSH REL STEL (ppm)

0.0002 (15min)

Calcium arsenate (as As)

Caprolactam

NIOSH Ceiling REL (mg/m3)

0.001 mg Cr(VI)/m3

tert-Butyl chromate n-Butyl glycidyl ether n-Butyl lactate n-Butyl mercaptan o-sec-Butylphenol p-tert-Butyltoluene n-Butyronitrile Cadmium dust (as Cd) Cadmium fume (as Cd)

NIOSH Ceiling REL (ppm)

5000 1 (skin)

9000 3 (skin)

II-119

Nigerian Electricity Health and Safety Standards

CHEMICAL NAME Carbon monoxide Carbon tetrabromide Carbon tetrachloride Carbonyl fluoride Catechol

NIOSH REL TWA (ppm)

NIOSH REL TWA (mg/m3)

35 0.1

40 1.4

2 5 (skin)

5 20 (skin)

Cellulose Cesium hydroxide Chlordane Chlorinated camphene Chlorinated diphenyl oxide Chlorine Chlorine dioxide Chlorine trifluoride Chloroacetaldehyde alpha-Chloroacetophenone Chloroacetyl chloride Chlorobenzene o-Chlorobenzylidene malononitrile Chlorobromomethane Chlorodifluoromethane Chlorodiphenyl (42% chlorine) Chlorodiphenyl (54% chlorine) Chloroform bis-Chloromethyl ether Chloromethyl methyl ether 1-Chloro-1-nitropropane Chloropentafluoroethane Chloropicrin beta-Chloroprene o-Chlorostyrene o-Chlorotoluene 2-Chloro-6-trichloromethyl pyridine Chlorpyrifos

II-120

Version 1: March 2008 NIOSH Ceiling REL (ppm)

NIOSH Ceiling REL (mg/m3)

200

229

NIOSH REL STEL (ppm)

NIOSH REL STEL (mg/m3)

0.3 2 (60min) 5

4 12.6 (60min) 15

0.3

0.9

1250

4375

2 (60min)

9.78 (60min)

75 75

428 375

10 (total) 5 (resp) 2 0.5 (skin) 0.5 0.1

0.5 (15min)

1.45 (15min)

0.1 1

0.4 3

0.05 (skin)

0.4 (skin)

0.3

0.05 0.05

0.3 0.2

200 1000

1050 3500 0.001 0.001

2 1000 0.1

10 6320 0.7

50 50

285 250

1 (15min)

3.6 (15min)

10 (total) 5 (resp) 0.2 (skin)

20 (total) 0.6 (skin)

Version 1: March 2008

CHEMICAL NAME

Part II: Safety and Best Industry Practices NIOSH REL TWA (ppm)

Chromic acid and chromates Chromium(II) compounds (as Cr) Chromium(III) compounds (as Cr) Chromium metal

NIOSH REL TWA (mg/m3)

NIOSH Ceiling REL (mg/m3)

NIOSH REL STEL (ppm)

NIOSH REL STEL (mg/m3)

0.001 0.5 0.5 0.5 0.001 mg Cr (VI)/m3

Chromyl chloride Clopidol

10 (total) 5 (resp)

Coal dust

2.4 (resp, <5% SiO2) 10 (resp, greater than or equal to 5% SiO2)

Coal tar pitch volatiles

0.1 ( cyclohexaneextractable fraction)

Cobalt carbonyl (as Co) Cobalt hydrocarbonyl (as Co) Cobalt metal dust and fume (as Co)

20 (total)

0.1 0.1 0.05 0.2 (benzenesoluble fraction)

Coke oven emissions Copper (dusts and mists, as Cu) Copper fume (as Cu) Cotton dust (raw)

1 0.1 <0.2

Crag® herbicide m-Cresol o-Cresol p-Cresol Crotonaldehyde Crufomate Cumene Cyanamide Cyanogen Cyanogen chloride

NIOSH Ceiling REL (ppm)

10 (total) 5 (resp) 2.3 2.3 2.3 2 50 (skin) 10

10 10 10 6 5 245 (skin) 2 20

20

0.3

0.6

II-121

Nigerian Electricity Health and Safety Standards

CHEMICAL NAME Cyclohexane Cyclohexanethiol Cyclohexanol Cyclohexanone Cyclohexene Cyclohexylamine Cyclonite Cyclopentadiene Cyclopentane Cyhexatin 2, 4-D DDT Decaborane 1-Decanethiol Demeton Diacetone alcohol 2, 4-Diaminoanisole (and its salts) o-Dianisidine Diazinon® Diazomethane Diborane 1, 2-Dibromo-3-chloropropane 2-N-Dibutylaminoethanol 2, 6-Di-tert-butyl-p-cresol Dibutyl phosphate Dibutyl phthalate Dichloroacetylene o-Dichlorobenzene p-Dichlorobenzene 3, 3'-Dichlorobenzidine (and its salts) Dichlorodifluoromethane 1, 3-Dichloro-5, 5-dimethylhydantoin 1, 1-Dichloroethane

II-122

Version 1: March 2008

NIOSH REL TWA (ppm)

NIOSH REL TWA (mg/m3)

300

1050

50 (skin) 25 (skin) 300 10

200 (skin) 100 (skin) 1015 40 1.5 (skin) 200 1720 5 10 0.5 0.3 (skin)

75 600

0.05 (skin)

NIOSH Ceiling REL (ppm)

NIOSH Ceiling REL (mg/m3)

0.5 (15min)

2.4 (15min)

NIOSH REL STEL (mg/m3)

3 (skin)

0.5 (15min) 50

NIOSH REL STEL (ppm)

0.15 (skin)

0.9 (skin)

2

10

3.6 (15min)

0.1 (skin) 240

(minimize occupational exposure)

0.2 0.1 2 (skin) 1

0.1 (skin) 0.4 0.1 14 (skin) 10 5 5 0.1 50

1000 100

4950 0.2 400

0.4 300

0.4

Version 1: March 2008

CHEMICAL NAME 1, 2-Dichloroethylene Dichloroethyl ether Dichloromonofluoromethane 1, 1-Dichloro-1-nitroethane 1, 3-Dichloropropene 2, 2-Dichloropropionic acid Dichlorotetrafluoroethane Dichlorvos Dicrotophos Dicyclopentadiene

Part II: Safety and Best Industry Practices NIOSH REL TWA (ppm)

NIOSH REL TWA (mg/m3)

200 5 (skin) 10 2 1 (skin) 1 1000

790 30 (skin) 40 10 5 (skin) 6 7000 1(skin) 0.25 (skin) 30

5

Dicyclopentadienyl iron Dieldrin Diesel exhaust Diethanolamine Diethylamine 2-Diethylaminoethanol Diethylenetriamine Diethyl ketone Diethyl phthalate Difluorodibromomethane Diglycidyl ether Diisobutyl ketone Diisopropylamine Dimethyl acetamide Dimethylamine 4-Dimethylaminoazobenzene bis(2-(Dimethylamino) ethyl) ether Dimethylaminopropionitrile N, N-Dimethylaniline Dimethyl carbamoyl chloride Dimethyl-1, 2-dibromo-2, 2-dichlorethyl phosphate Dimethylformamide 1, 1-Dimethylhydrazine Dimethylphthalate

NIOSH Ceiling REL (ppm)

NIOSH Ceiling REL (mg/m3)

NIOSH REL STEL (ppm)

NIOSH REL STEL (mg/m3)

10 (skin)

60 (skin)

25

75

10 (skin)

50 (skin)

10 (total) 5 (resp) 0.25 (skin) 3 10 10 (skin) 1 (skin) 200 100 0.1 25 5 (skin) 10 (skin) 10

15 30 50 (skin) 4 (skin) 705 5 860 0.5 150 20 (skin) 35 (skin) 18

5 (skin)

25 (skin)

10 (skin)

3 (skin) 30 (skin) 0.06 (2hr)

0.15 (2hr)

5

II-123

Nigerian Electricity Health and Safety Standards

CHEMICAL NAME Dimethyl sulfate Dinitolmide m-Dinitrobenzene o-Dinitrobenzene p-Dinitrobenzene Dinitro-o-cresol Dinitrotoluene Di-sec octyl phthalate Dioxane Dioxathion Diphenyl Diphenylamine Dipropylene glycol methyl ether Dipropyl ketone Diquat (Diquat dibromide) Disulfiram Disulfoton Diuron Divinyl benzene 1-Dodecanethiol Emery Endosulfan Endrin Enflurane Epichlorohydrin EPN Ethanolamine Ethion 2-Ethoxyethanol 2-Ethoxyethyl acetate Ethyl acetate Ethyl acrylate Ethyl alcohol Ethylamine Ethyl benzene

II-124

Version 1: March 2008

NIOSH REL TWA (ppm)

NIOSH REL TWA (mg/m3)

0.1 (skin)

0.5 (skin) 5 1 (skin) 1 (skin) 1 (skin) 0.2 (skin) 1.5 (skin) 5

0.2 100 (skin) 50

10

NIOSH Ceiling REL (ppm)

NIOSH Ceiling REL (mg/m3)

1 (30min)

3.6 (30min)

NIOSH REL STEL (ppm)

NIOSH REL STEL (mg/m3)

10

0.2 (skin) 1 10 600 (skin) 235 0.5 2 0.1 (skin) 10 50 0.5( 15min)

4.1 (15min)

2 (60min)

15.1 (60min)

150 (skin)

900 (skin)

6

15

125

545

0.1 (skin) 0.1 (skin) 5 (skin)

0.5 (skin) 0.5 (skin) 400

19 (skin) 0.5 (skin) 8 0.4 (skin) 1.8 (skin) 2.7 (skin) 1400

1000 10 100

1900 18 435

3

Version 1: March 2008

CHEMICAL NAME Ethyl bromide Ethyl butyl ketone Ethyl chloride Ethylene chlorohydrin Ethylenediamine Ethylene dibromide Ethylene dichloride Ethylene glycol Ethylene glycol dinitrate Ethyleneimine Ethylene oxide Ethylene thiourea Ethyl ether Ethyl formate Ethylidene norbornene Ethyl mercaptan N-Ethylmorpholine Ethyl silicate Fenamiphos Fensulfothion Fenthion Ferbam Ferrovanadium dust

Part II: Safety and Best Industry Practices NIOSH REL TWA (ppm)

NIOSH REL TWA (mg/m3)

50

230

NIOSH Ceiling REL (mg/m3)

1 (skin)

3 (skin)

NIOSH REL STEL (ppm)

NIOSH REL STEL (mg/m3)

2

8

(handle with caution in the workplace) 10 0.045 (15min) 1

25

<0.1 (10min) <0.1 (10min)

0.18 (10min) 0.18 (10min)

100

300

0.13 (15min) 4

0.1 (skin)

5 (skin) 10

5 (10min) 5 (10min)

9 (10min) 9 (10min)

5 0.5 (15min)

25 1.3 (15min)

23 (skin) 85 0.1 (skin) 0.1 10 1

3

5 (total) 3 fibers/cm3 (fiber diameter < or = to 3.5um)

Fibrous glass dust Fluorine Fluorotrichloromethane Fluoroxene Fonofos Formaldehyde Formalin (as formaldehyde)

NIOSH Ceiling REL (ppm)

0.1

0.2 1000 2 (60min)

5600 10.3 (60min)

0.1 (skin) 0.016 (15min) 0.016 (15min)

0.1 (15min) 0.1 (15min)

II-125

Nigerian Electricity Health and Safety Standards

CHEMICAL NAME Formamide Formic acid Furfural Furfuryl alcohol Gasoline Germanium tetrahydride Glutaraldehyde Glycerin (mist) Glycidol Glycolonitrile Grain dust (oat, wheat, barley) Graphite (natural)

Version 1: March 2008

NIOSH REL TWA (ppm)

NIOSH REL TWA (mg/m3)

10 (skin) 5

15 (skin) 9

10 (skin)

40 (skin)

0.2

0.6

25

0.2

0.8

2 (15min)

5 (15min)

2 (60min)

16.2 (60min)

440 (15min) 0.5 (15min)

1800 (15min) 2.7 (15min)

0.5 (15min)

5.3 (15min)

0.020 (10min)

0.140 (10min)

510 (15min) 0.5 (15min)

1800 (15min) 2.7 (15min)

NIOSH REL STEL (ppm)

NIOSH REL STEL (mg/m3)

15 (skin)

60 (skin)

75

300

4 2.5 (resp) 15 (total) 5 (resp)

Gypsum

10 (total) 5 (resp)

II-126

NIOSH Ceiling REL (mg/m3)

75

Graphite (synthetic)

Hafnium Halothane Heptachlor n-Heptane 1-Heptanethiol Hexachlorobutadiene Hexachlorocyclopentadiene Hexachloroethane Hexachloronaphthalene 1-Hexadecanethiol Hexafluoroacetone Hexamethylene diisocyanate Hexamethyl phosphoramide n-Hexane Hexane isomers (excluding n-Hexane) n-Hexanethiol 2-Hexanone Hexone sec-Hexyl acetate

NIOSH Ceiling REL (ppm)

0.5

85 (15min)

0.5 (skin) 350 (15min)

0.02 (skin) 0.01 1 (skin)

0.24 (skin) 0.1 10 (skin) 0.2 (skin)

0.1 (skin) 0.005 (10min)

0.7 (skin) 0.035 (10min)

50 100 (15min)

180 350 (15min)

1 50 50

4 205 300

Version 1: March 2008

CHEMICAL NAME Hexylene glycol Hydrazine Hydrogenated terphenyls Hydrogen bromide Hydrogen chloride Hydrogen cyanide Hydrogen fluoride Hydrogen peroxide Hydrogen selenide Hydrogen sulfide Hydroquinone 2-Hydroxypropyl acrylate Indene Indium Iodine Iodoform Iron oxide dust and fume (as Fe) Iron pentacarbonyl (as Fe) Iron salts (soluble, as Fe) Isoamyl acetate Isoamyl alcohol (secondary) Isoamyl alcohol (primary) Isobutane Isobutyl acetate Isobutyl alcohol Isobutyronitrile Isooctyl alcohol Isophorone Isophorone diisocyanate 2-Isopropoxyethanol Isopropyl acetate Isopropyl alcohol Isopropylamine N-Isopropylaniline Isopropyl ether

Part II: Safety and Best Industry Practices NIOSH REL TWA (ppm)

0.5

3(15min) 1 0.05

NIOSH REL TWA (mg/m3)

NIOSH Ceiling REL (ppm)

NIOSH Ceiling REL (mg/m3)

25 0.03 (2hour)

125 0.04 (2hour)

3 5

10 7

6(15min)

5 (15min)

10 (10min)

15 (10min) 2 (15min)

0.1

1

NIOSH REL STEL (ppm)

NIOSH REL STEL (mg/m3)

4.7 (skin)

5 (skin)

0.2

0.45

5

2.5(15min) 1.4 0.2

0.5 (skin) 10

3 (skin) 45 0.1

0.6

100 100 100 800 150 50 8 50 (skin) 4 0.005 (skin)

10 5 0.23 1 525 360 360 1900 700 150 22 270 (skin) 23 0.045 (skin)

125 125

450 450

0.02 (skin)

0.180 (skin)

400

980

500

1225

2 (skin) 500

10 (skin) 2100

0.1

II-127

Nigerian Electricity Health and Safety Standards

CHEMICAL NAME

NIOSH REL TWA (ppm)

Version 1: March 2008 NIOSH REL TWA (mg/m3)

Isopropyl glycidyl ether Kaolin Kepone Kerosene Ketene Lead

0.5

NIOSH REL STEL (mg/m3)

1.5

3

1000

0.5 (skin) 0.025 1800 10 (total) 5 (resp)

0.25 3

10 (skin) 1 8 1 0.1 (skin)

10 (total) 5 (resp)

Mercury compounds [except (organo) alkyls] (as Hg)

0.05 (vapor/skin)

II-128

240 (15min)

0.001 100 0.9 0.050

Marble

Mercury (organo) alkyl compounds (as Hg) Mesityl oxide Methacrylic acid Methomyl Methoxychlor Methoxyflurane 4-Methoxyphenol Methyl acetate Methyl acetylene

50 (15min)

NIOSH REL STEL (ppm)

10 (total) 5 (resp)

Magnesite Magnesium oxide fume Malathion Maleic anhydride Malonaldehyde Malononitrile Manganese compounds and fume (as Mn) Manganese cyclopentadienyl tricarbonyl (as Mn) Manganese tetroxide (as Mn)

NIOSH Ceiling REL (mg/m3)

10 (total) 5 (resp)

Limestone Lindane Lithium hydride L.P.G.

NIOSH Ceiling REL (ppm)

10 20 (skin)

3

0.1 (skin)

0.01 (skin) 40 70 (skin) 2.5

0.03 (skin)

2 (60min) 200 1000

5 610 1650

13.5 (60min) 250

760

Version 1: March 2008

CHEMICAL NAME Methyl acetylene-propadiene mixture Methyl acrylate Methylacrylonitrile Methylal Methyl alcohol Methylamine Methyl bromide Methyl Cellosolve® Methyl Cellosolve® acetate Methyl chloride Methyl chloroform Methyl-2-cyanoacrylate Methylcyclohexane Methylcyclohexanol o-Methylcyclohexanone

Part II: Safety and Best Industry Practices NIOSH REL TWA (ppm)

NIOSH REL TWA (mg/m3)

1000 10 (skin) 1 (skin) 1000 200 (skin) 10

1800 35 (skin) 3 (skin) 3100 260 (skin) 12

0.1 (skin) 0.1 (skin)

0.3 (skin) 0.5 (skin)

2 400 50 50 (skin)

8 1600 235 230 (skin)

350 (15min)

Methyl cyclopentadienyl manganese tricarbonyl (as Mn) Methyl demeton Methylene bisphenyl isocyanate Methylene chloride 4, 4'-Methylenebis(2-chloroaniline) Methylene bis(4-cyclohexylisocyanate) 4, 4'-Methylenedianiline Methyl ethyl ketone peroxide Methyl formate 5-Methyl-3-heptanone Methyl hydrazine Methyl iodide Methyl isoamyl ketone Methyl isobutyl carbinol Methyl isocyanate Methyl isopropyl ketone Methyl mercaptan Methyl methacrylate Methyl (n-amyl) ketone

NIOSH Ceiling REL (ppm)

NIOSH Ceiling REL (mg/m3)

NIOSH REL STEL (ppm)

NIOSH REL STEL (mg/m3)

1250

2250

250 (skin)

325 (skin)

4

16

75 (skin)

345 (skin)

150

375

40 (skin)

165 (skin)

1900 (15min)

0.2 (skin)

0.005 (10min)

0.5 (skin) 0.05 (10min)

0.02 (10min)

0.20 (10min)

0.01

0.11

0.2

1.5

0.003 (skin)

100 25

250 130

2 (skin) 50 25 (skin) 0.02 (skin) 200

10 (skin) 240 100 (skin) 0.05 (skin) 705

100 100

410 465

0.04 (2hour)

0.5 (15min)

0.08 (2hour)

1 (15min)

II-129

Nigerian Electricity Health and Safety Standards

CHEMICAL NAME Methyl parathion Methyl silicate alpha-Methyl styrene Metribuzin Mica (containing less than 1% quartz)

NIOSH REL TWA (ppm) 1 50

II-130

NIOSH REL TWA (mg/m3)

NIOSH Ceiling REL (ppm)

NIOSH Ceiling REL (mg/m3)

0.2 (skin) 6 240 5 3 (resp)

NIOSH REL STEL (ppm)

NIOSH REL STEL (mg/m3)

100

485

30 (skin)

105 (skin)

15

75

4

10

1

1.8

3 fibers/cm3 (fiber diameter < or = to 3.5um) 5 mg/m3 (total)

Mineral wool fiber Molybdenum Molybdenum (soluble compounds, as Mo) Monocrotophos Monomethyl aniline Morpholine Naphtha (coal tar) Naphthalene Naphthalene diisocyanate alpha-Naphthylamine beta-Naphthylamine Niax® Catalyst ESN Nickel carbonyl Nickel metal and other compounds (as Ni) Nicotine Nitric acid Nitric oxide p-Nitroaniline Nitrobenzene 4-Nitrobiphenyl p-Nitrochlorobenzene Nitroethane Nitrogen dioxide Nitrogen trifluoride Nitroglycerine Nitromethane 2-Nitronaphthalene

Version 1: March 2008

0.5 (skin) 20 (skin) 100 10 0.005

0.001

0.25 2 (skin) 70 (skin) 400 50 0.040

1 (skin)

0.007 0.015 0.5 (skin) 5 30 3 (skin) 5 (skin)

100

310

10

29

2 25

0.020 (10min)

0.170 (10min)

0.1 (skin)

Version 1: March 2008

CHEMICAL NAME 1-Nitropropane 2-Nitropropane N-Nitrosodimethylamine m-Nitrotoluene o-Nitrotoluene p-Nitrotoluene Nitrous oxide Nonane 1-Nonanethiol Octachloronaphthalene 1-Octadecanethiol Octane 1-Octanethiol Oil mist (mineral) Osmium tetroxide Oxalic acid Oxygen difluoride Ozone Paraffin wax fume Paraquat (Paraquat dichloride) Parathion Particulates not otherwise regulated Pentaborane Pentachloroethane

Part II: Safety and Best Industry Practices NIOSH REL TWA (ppm)

NIOSH REL TWA (mg/m3)

25

90

2 (skin) 2 (skin) 2 (skin) 25 200

11 (skin) 11 (skin) 11 (skin) 46 1050

NIOSH Ceiling REL (mg/m3)

0.5 (15min)

3.3 (15min)

0.5 (15min) 385 (15min) 0.5 (15min)

5.9 (15min) 1800 (15min) 3.0 (15min)

NIOSH REL STEL (ppm)

0.1 (skin) 75 (15min)

350 (15min)

0.0002

5 0.002 1

NIOSH REL STEL (mg/m3)

0.3 (skin)

0.05 0.1

0.0006

10 0.006 2

0.015

0.03

6

28

0.1 0.2

2 0.1 (resp/skin) 0.05 (skin) 0.005

0.01

(handle with caution in the workplace)

Pentachloronaphthalene Pentachlorophenol

0.5 (skin) 0.5 (skin)

Pentaerythritol n-Pentane 1-Pentanethiol 2-Pentanone Perchloromethyl mercaptan Perchloryl fluoride

NIOSH Ceiling REL (ppm)

10 (total) 5 (resp) 120 (15min)

350 (15min)

150 0.1 3

530 0.8 14

610 (15min) 0.5 (15min)

1800 (15min) 2.1 (15min)

II-131

Nigerian Electricity Health and Safety Standards

CHEMICAL NAME

NIOSH REL TWA (ppm)

Perlite Petroleum distillates (naphtha) Phenol Phenothiazine p-Phenylene diamine Phenyl ether-biphenyl mixture (vapor) Phenyl ether (vapor) Phenyl glycidyl ether

Version 1: March 2008 NIOSH REL TWA (mg/m3)

Plaster of Paris Platinum Platinum (soluble salts, as Pt) Portland cement

II-132

NIOSH Ceiling REL (mg/m3)

15.6 (15min)

1800 (15min) 60 (15min)

1 (15min)

6 (15min)

0.14 (2hour/skin)

0.6 (2hour/skin)

0.05

0.25

NIOSH REL STEL (ppm)

NIOSH REL STEL (mg/m3)

10 (total) 5 (resp)

5 (15min)

1 1

350 (15min) 19 (15min) 5 (skin) 0.1 (skin) 7 7

Phenylhydrazine N-Phenyl-beta-naphthylamine Phenylphosphine Phorate Phosdrin® Phosgene Phosphine Phosphoric acid Phosphorus oxychloride Phosphorus pentachloride Phosphorus pentasulfide Phosphorus trichloride Phosphorus (yellow) Phthalic anhydride m-Phthalodinitrile Picloram Picric acid Pindone Piperazine dihydrochloride

NIOSH Ceiling REL (ppm)

0.01 (skin) 0.1 (15min) 0.3 0.1

0.2 1

0.05 (skin) 0.1 (skin) 0.4 (15min) 0.4 1 0.6 1 1 1.5 0.1 6 5 0.1 (skin) 0.1 5 10 (total) 5 (resp) 1 0.002 10 (total) 5 (resp)

0.03 (skin) 0.2 (15min)

0.2 (skin) 0.3 (skin)

0.8 (15min) 1 0.5

1 3 3

0.5

3 3

0.3 (skin)

Version 1: March 2008

CHEMICAL NAME Potassium cyanide (as CN) Potassium hydroxide Propane Propane sultone 1-Propanethiol Propargyl alcohol beta-Propiolactone Propionic acid Propionitrile Propoxur n-Propyl acetate n-Propyl alcohol Propylene dichloride Propylene glycol dinitrate Propylene glycol monomethyl ether Propylene imine Propylene oxide n-Propyl nitrate Pyrethrum Pyridine Quinone Resorcinol

Part II: Safety and Best Industry Practices NIOSH REL TWA (ppm)

1000

1800

1 (skin)

2 (skin)

10 6 200 200 (skin)

30 14 0.5 840 500 (skin)

0.05 (skin) 100 2 (skin)

0.3 (skin) 360 5 (skin)

25

105 5 15 0.4 45

5 0.1 10

Rhodium (metal fume and insoluble compounds, as Rh)

NIOSH Ceiling REL (ppm)

NIOSH Ceiling REL (mg/m3)

4.7 (10min)

5 (10min) 2

0.5 (15min)

1.6 (15min)

NIOSH REL STEL (ppm)

NIOSH REL STEL (mg/m3)

15

45

250 250 (skin)

1050 625 (skin)

150

540

40

170

20

90

0.1

Rhodium (soluble compounds, as Rh) Ronnel

0.001 10

Rosin core solder, pyrolysis products (as formaldehyde) Rotenone Rouge Selenium Selenium hexafluoride Silica, amorphous Silica, crystalline (as respirable dust)

NIOSH REL TWA (mg/m3)

0.1 5 0.2 0.05 6 0.05

II-133

Nigerian Electricity Health and Safety Standards

CHEMICAL NAME

NIOSH REL TWA (ppm)

Version 1: March 2008 NIOSH REL TWA (mg/m3)

Silicon

10 (total) 5 (resp)

Silicon carbide

10 (total 5 (resp)

Silicon tetrahydride Silver (metal dust and soluble compounds, as Ag) Soapstone (containing less than 1% quartz) Sodium aluminum fluoride (as F)

5

0.1 (as HN3 on skin)

0.3 (as NaN3 on skin)

4.7 (10min)

5 (10min)

NIOSH REL STEL (ppm)

2.5 0.05 (skin)

0.15 (skin) 2

5 10 (total) 5 (resp) 0.1

50

0.5 350 (15min) 0.15 215

1800 (15min) 100

6

Sucrose Sulfur dioxide Sulfur hexafluoride Sulfuric acid Sulfur monochloride Sulfur pentafluoride Sulfur tetrafluoride Sulfuryl fluoride Sulprofos 2, 4, 5-T

II-134

425 0.00006 (60min)

Subtilisins Succinonitrile

NIOSH REL STEL (mg/m3)

5

Starch Stibine Stoddard solvent Strychnine Styrene

NIOSH Ceiling REL (mg/m3)

7 0.01 6 (total) 3 (resp) 2.5

Sodium azide Sodium bisulfite Sodium cyanide (as CN) Sodium fluoride (as F) Sodium fluoroacetate Sodium hydroxide Sodium metabisulfite

NIOSH Ceiling REL (ppm)

20 10 (total 5 (resp)

2 1000

5 6000 1 1 0.01 0.1

5

20 1 10

5

13

10

40

6 0.1 0.4

Version 1: March 2008

CHEMICAL NAME

Part II: Safety and Best Industry Practices NIOSH REL TWA (ppm)

Talc (containing no asbestos and less than 1% quartz) Tantalum (metal and oxide dust, as Ta) TEDP Tellurium Tellurium hexafluoride

1, 1, 1, 2-Tetrachloroethane 1, 1, 2, 2-Tetrachloroethane Tetrachloroethylene Tetrachloronaphthalene Tetraethyl lead (as Pb) Tetrahydrofuran Tetramethyl lead (as Pb) Tetramethyl succinonitrile Tetranitromethane Tetrasodium pyrophosphate Tetryl Thallium (soluble compounds, as Tl)

0.02

NIOSH Ceiling REL (mg/m3)

NIOSH REL STEL (ppm)

NIOSH REL STEL (mg/m3)

5 0.2 (skin) 0.1 0.2

10

10 (total) 5 (resp) 0.05 (skin) 0.5 0.5 0.5 500 500

5 5 5

4170 4170

(handle with caution in the workplace) 1 (skin)

7 (skin)

(minimize occupational exposure)

200 0.5 (skin) 1

4, 4'-Thiobis(6-tert-butyl-m-cresol) Thioglycolic acid Thionyl chloride Thiram

NIOSH Ceiling REL (ppm)

2 (resp)

Temephos TEPP m-Terphenyl o-Terphenyl p-Terphenyl 2, 3, 7, 8-Tetrachloro-dibenzo-p-dioxin 1, 1, 1, 2-Tetrachloro-2, 2-difluoroethane 1, 1, 2, 2-Tetrachloro-1, 2-difluoroethane

NIOSH REL TWA (mg/m3)

2 (skin) 0.075 (skin) 590 0.075 (skin) 3 (skin) 8 5 1.5 (skin) 0.1 (skin)

250

735

10 (total) 5 (resp) 1 (skin)

4 (skin) 1

5

5

II-135

Nigerian Electricity Health and Safety Standards

CHEMICAL NAME

NIOSH REL TWA (ppm)

Tin Tin (organic compounds, as Sn) Tin(II) oxide (as Sn) Tin(IV) oxide (as Sn) Titanium dioxide

Version 1: March 2008 NIOSH REL TWA (mg/m3)

NIOSH Ceiling REL (ppm)

II-136

NIOSH REL STEL (ppm)

NIOSH REL STEL (mg/m3)

150

560

1250

9500

15

36

2 0.1 (skin) 2 2 0.02 (60min/skin)

o-Tolidine Toluene Toluenediamine Toluene-2, 4-diisocyanate m-Toluidine o-Toluidine p-Toluidine Tributyl phosphate Trichloroacetic acid 1, 2, 4-Trichlorobenzene 1, 1, 2-Trichloroethane Trichloroethylene Trichloronaphthalene 1, 2, 3-Trichloropropane 1, 1, 2-Trichloro-1, 2, 2-trifluoroethane Triethylamine Trifluorobromomethane Trimellitic anhydride Trimethylamine 1, 2, 3-Trimethylbenzene 1, 2, 4-Trimethylbenzene 1, 3, 5-Trimethylbenzene Trimethyl phosphite 2, 4, 6-Trinitrotoluene Triorthocresyl phosphate Triphenylamine Triphenyl phosphate Tungsten Tungsten carbide (cemented)

NIOSH Ceiling REL (mg/m3)

100

375

0.2 1

2.5 7

10 (skin)

45 (skin)

10 (skin) 1000

5 (skin) 60 (skin) 7600

5

1000 0.005 10 25 25 25 2

6100 0.04 24 125 125 125 10 0.5 (skin) 0.1 (skin) 5 3 5

40

10

Version 1: March 2008

CHEMICAL NAME Tungsten (soluble compounds, as W) Turpentine 1-Undecanethiol Uranium (insoluble compounds, as U) Uranium (soluble compounds, as U) n-Valeraldehyde

Part II: Safety and Best Industry Practices NIOSH REL TWA (ppm)

NIOSH REL TWA (mg/m3)

100

1 560

50

0.2 0.05 175

NIOSH Ceiling REL (ppm)

NIOSH Ceiling REL (mg/m3)

3.9 (15min) 0.6

Vanadium dust

0.05 mg V/m3 (15min)

Vanadium fume

0.05 mg V/m3 (15min)

Vinyl acetate Vinyl bromide Vinyl chloride Vinyl cyclohexene dioxide Vinyl fluoride Vinylidene chloride Vinylidene fluoride Vinyl toluene

NIOSH REL STEL (mg/m3) 3

0.5 (15min)

Vegetable oil mist

NIOSH REL STEL (ppm)

10 (total) 5 (resp) 4 (15min)

10 (skin) 1

60 (skin) 5

1 100

VM & P Naphtha

5 480 350 (15min)

Warfarin

15 (15min)

1800 (15min)

0.1

Welding fumes Wood dust

1

m-Xylene

100

435

150

655

o-Xylene

100

435

150

655

p-Xylene

100

435

150

655

m-Xylene-alpha, alpha'-diamine Xylidine

0.1 (skin) 2 (skin)

10 (skin)

Yttrium

1

Zinc chloride fume

1

Zinc oxide

5 (dust) 5 (fume)

Zinc stearate

10 (total) 5 (resp)

Zirconium compounds (as Zr)

5

2 15 (dust)

10 (fume) 10

II-137

Nigerian Electricity Health and Safety Standards

Version 1: March 2008

Table 10. NIOSH Immediately Dangerous to Life and Health (IDLH) Values Chemical Name

Original IDLH

Revised IDLH

Acetaldehyde

10,000 ppm

2,000 ppm

Acetic acid

1,000 ppm

50 ppm

Acetic anhydride

1,000 ppm

200 ppm

Acetone

20,000 ppm

2,500 ppm [LEL]

Acetonitrile

4,000 ppm

500 ppm

Acetylene tetrabromide

10 ppm

8 ppm

Acrolein

5 ppm

2 ppm

Acrylamide

Unknown

60 mg/m

Acrylonitrile

500 ppm

Aldrin

100 mg/m

Allyl alcohol

150 ppm

20 ppm

Allyl chloride

300 ppm

250 ppm

Allyl glycidyl ether

270 ppm

50 ppm

2 Aminopyridine

5 ppm

5 ppm [Unch]

3

85 ppm 3

Ammonia

500 ppm

Ammonium sulfamate

5,000 mg/m

n-Amyl acetate

4,000 ppm

25 mg/m

3

300 ppm 3

1,500 mg/m

3

1,000 ppm

sec-Amyl acetate

9,000 ppm

1,000 ppm

Aniline

100 ppm

100 ppm [Unch]

o-Anisidine

50 mg/m

3

50 mg/m [Unch]

p-Anisidine

50 mg/m

3

50 mg/m [Unch]

Antimony compounds (as Sb)

80 mg Sb/m

3 3

3

100 mg/m

Arsenic (inorganic compounds, as As)

100 mg As/m 6 ppm

Azinphosmethyl

20 mg/m

3

3

ANTU Arsine

50 mg Sb/m

3

100 mg/m [Unch] 3

5 mg As/m

3

3 ppm 3

10 mg/m 3

3

1,100 mg Ba/m

Benzene

3,000 ppm

Benzoyl peroxide Benzyl chloride

7,000 mg/m 10 ppm

Beryllium compounds (as Be)

10 mg Be/m

Boron oxide

N.E.

2,000 mg/m

Boron trifluoride

100 ppm

25 ppm

Bromine

10 ppm

3 ppm

Bromoform

Unknown

850 ppm

1,3-Butadiene 2-Butanone 2-Butoxyethanol n-Butyl acetate sec-Butyl acetate tert-Butyl acetate n-Butyl alcohol sec-Butyl alcohol tert-Butyl alcohol n-Butylamine

20,000 ppm [LEL] 3,000 ppm 700 ppm 10,000 ppm 10,000 ppm 10,000 ppm 8,000 ppm 10,000 ppm 8,000 ppm 2,000 ppm 3 30 mg/m (as CrO3) 3,500 ppm

2,000 ppm [LEL] 3,000 ppm [Unch] 700 ppm [Unch] 1,700 ppm [LEL] 1,700 ppm [LEL] 1,500 ppm [LEL] 1,400 ppm [LEL] 2,000 ppm 1,600 ppm 300 ppm

tert-Butyl chromate n-Butyl glycidyl ether

II-138

50 mg Ba/m

3

Barium (soluble compounds, as Ba)

500 ppm 3

1,500 mg/m 10 ppm [Unch]

3

3

4 mg Be/m

3 3

15 mg Cr(VI)/m 250 ppm

3

Version 1: March 2008

Part II: Safety and Best Industry Practices

Chemical Name

Original IDLH

Revised IDLH

n-Butyl mercaptan p-tert-Butyltoluene Cadmium dust (as Cd)

2,500 ppm 1,000 ppm 3 50 mg Cd/m

Cadmium fume (as Cd) Calcium arsenate (as As) Calcium oxide Camphor (synthetic) Carbaryl Carbon black Carbon dioxide Carbon disulfide Carbon monoxide Carbon tetrachloride Chlordane Chlorinated camphene Chlorinated diphenyl oxide Chlorine Chlorine dioxide Chlorine trifluoride Chloroacetaldehyde alpha-Chloroacetophenone Chlorobenzene o-Chlorobenzylidene malononitrile Chlorobromomethane Chlorodiphenyl (42% chlorine) Chlorodiphenyl (54% chlorine) Chloroform 1-Chloro-1-nitropropane Chloropicrin beta-Chloroprene Chromic acid and chromates Chromium (II) compounds [as Cr(II)] Chromium (III) compounds [as Cr(III)] Chromium metal (as Cr) Coal tar pitch volatiles

9 mg Cd/m 3 100 mg As/m Unknown 3 200 mg/m 3 600 mg/m N.E. 50,000 ppm 500 ppm 1,500 ppm 300 ppm 3 500 mg/m 3 200 mg/m Unknown 30 ppm 10 ppm 20 ppm 100 ppm 3 100 mg/m 2,400 ppm 3 2 mg/m 5,000 ppm 3 10 mg/m 3 5 mg/m 1,000 ppm 2,000 ppm 4 ppm 400 ppm 3 30 mg/m (as CrO3) N.E. N.E. N.E. 3 700 mg/m

500 ppm 100 ppm 3 9 mg Cd/m 3 9 mg Cd/m [Unc h] 3 5 mg As/m 3 25 mg/m 3 200 mg/m [Unch] 3 100 mg/m 3 1,750 mg/m 40,000 ppm 500 ppm [Unch] 1,200 ppm 200 ppm 3 100 mg/m 3 200 mg/m [Unch] 3 5 mg/m 10 ppm 5 ppm 20 ppm [Unch] 45 ppm 3 15 mg/m 1,000 ppm 3 2 mg/m [Unch] 2,000 ppm 3 5 mg/m 3 5 mg/m [Unch] 500 ppm 100 ppm 2 ppm 300 ppm

Cobalt metal, dust and fume (as Co) Copper (dusts and mists, as Cu) Copper fume (as Cu) Cotton dust (raw) Crag (r) herbicide

20 mg Co/m N.E. N.E. N.E. 3 5,000 mg/m

15 mg Cr(VI)/m 3 250 mg Cr(II)/m 3 25 mg Cr(III)/m 3 250 mg Cr/m 3 80 mg/m 3 20 mg Co/m [Unch] 3 100 mg Cu/m 3 100 mg Cu/m 3 100 mg/m 3 500 mg/m

Cresol (o, m, p isomers) Crotonaldehyde Cumene Cyanides (as CN) Cyclohexane Cyclohexanol Cyclohexanone Cyclohexene Cyclopentadiene

250 ppm 400 ppm 8,000 ppm 3 50 mg/m (as CN) 10,000 ppm 3,500 ppm 5,000 ppm 10,000 ppm 2,000 ppm

250 ppm [Unch] 50 ppm 900 ppm [LEL] 3 25 mg/m (as CN) 1,300 ppm [LEL] 400 ppm 700 ppm 2,000 ppm 750 ppm

3

3

3

II-139

Nigerian Electricity Health and Safety Standards

Chemical Name

Original IDLH

2,4-D DDT Decaborane Demeton Diacetone alcohol Diazomethane Diborane Dibutyl phosphate Dibutyl phthalate o-Dichlorobenzene p-Dichlorobenzene Dichlorodifluoromethane 1,3-Dichloro 5,5-dimethylhydantoin 1,1-Dichloroethane 1,2-Dichloroethylene Dichloroethyl ether Dichloromonofluoromethane 1,1-Dichloro 1-nitroethane Dichlorotetrafluoroethane Dichlorvos Dieldrin Diethylamine 2-Diethylaminoethanol Difluorodibromomethane Diglycidyl ether Diisobutyl ketone Diisopropylamine Dimethyl acetamide Dimethylamine N,N-Dimethylaniline

500 mg/m N.E. 3 100 mg/m 3 20 mg/m 2,100 ppm 2 ppm 40 ppm 125 ppm 3 9,300 mg/m 1,000 ppm 1,000 ppm 50,000 ppm Unknown 4,000 ppm 4,000 ppm 250 ppm 50,000 ppm 150 ppm 50,000 ppm 3 200 mg/m 3 450 mg/m 2,000 ppm 500 ppm 2,500 ppm 25 ppm 2,000 ppm 1,000 ppm 400 ppm 2,000 ppm 100 ppm

Dimethyl 1,2-dibromo 2,2-dichlorethyl phosphate Dimethylformamide 1,1-Dimethylhydrazine Dimethylphthalate Dimethyl sulfate

1,800 mg/m 3,500 ppm 50 ppm 3 9,300 mg/m 10 ppm

Dinitrobenzene (o, m, p isomers) Dinitroocresol Dinitrotoluene Di sec-octyl phthalate Dioxane Diphenyl Dipropylene glycol methyl ether Endrin Epichlorohydrin EPN Ethanolamine 2-Ethoxyethanol 2-Ethoxyethyl acetate Ethyl acetate Ethyl acrylate

200 mg/m 3 5 mg/m 3 200 mg/m Unknown 2,000 ppm 3 300 mg/m Unknown 3 2,000 mg/m 250 ppm 3 50 mg/m 1,000 ppm 6,000 ppm 2,500 ppm 10,000 ppm 2,000 ppm

II-140

3

3

3

Version 1: March 2008

Revised IDLH 3

100 mg/m 3 500 mg/m 3 15 mg/m 3 10 mg/m 1,800 ppm [LEL] 2 ppm [Unch] 15 ppm 30 ppm 3 4,000 mg/m 200 ppm 150 ppm 15,000 ppm 3 5 mg/m 3,000 ppm 1,000 ppm 100 ppm 5,000 ppm 25 ppm 15,000 ppm 3 100 mg/m 3 50 mg/m 200 ppm 100 ppm 2,000 ppm 10 ppm 500 ppm 200 ppm 300 ppm 500 ppm 100 ppm [Unch] 3

200 mg/m 500 ppm 15 ppm 3 2,000 mg/m 7 ppm

3

50 mg/m 3 5 mg/m [Unch] 3 50 mg/m 3 5,000 mg/m 500 ppm 3 100 mg/m 600 ppm 3 2 mg/m 75 ppm 3 5 mg/m 30 ppm 500 ppm 500 ppm 2,000 ppm [LEL] 300 ppm

Version 1: March 2008

Part II: Safety and Best Industry Practices

Chemical Name

Original IDLH

Revised IDLH

Ethyl alcohol Ethylamine Ethyl benzene Ethyl bromide Ethyl butyl ketone Ethyl chloride Ethylene chlorohydrin Ethylenediamine Ethylene dibromide Ethylene dichloride Ethylene glycol dinitrate Ethyleneimine Ethylene oxide Ethyl ether Ethyl formate Ethyl mercaptan N-Ethylmorpholine Ethyl silicate Ferbam Ferrovanadium dust Fluorides (as F) Fluorine Fluorotrichloromethane Formaldehyde Formic acid Furfural Furfuryl alcohol Glycidol Graphite (natural) Hafnium compounds (as Hf) Heptachlor n-Heptane Hexachloroethane Hexachloronaphthalene n-Hexane 2-Hexanone Hexone sec Hexyl acetate Hydrazine Hydrogen bromide Hydrogen chloride Hydrogen cyanide Hydrogen fluoride (as F) Hydrogen peroxide Hydrogen selenide (as Se) Hydrogen sulfide Hydroquinone Iodine Iron oxide dust and fume (as Fe) Isoamyl acetate Isoamyl alcohol (primary) Isoamyl alcohol (secondary) Isobutyl acetate

15,000 ppm 4,000 ppm 2,000 ppm 3,500 ppm 3,000 ppm 20,000 ppm 10 ppm 2,000 ppm 400 ppm 1,000 ppm 3 500 mg/m 100 ppm 800 ppm 19,000 ppm [LEL] 8,000 ppm 2,500 ppm 2,000 ppm 1,000 ppm N.E. N.E. 3 500 mg F/m 25 ppm 10,000 ppm 30 ppm 30 ppm 250 ppm 250 ppm 500 ppm N.E. Unknown 3 700 mg/m 5,000 ppm 300 ppm 3 2 mg/m 5,000 ppm 5,000 ppm 3,000 ppm 4,000 ppm 80 ppm 50 ppm 100 ppm 50 ppm 30 ppm 75 ppm 2 ppm 300 ppm Unknown 10 ppm N.E. 3,000 ppm 10,000 ppm 10,000 ppm 7,500 ppm

3,300 ppm [LEL] 600 ppm 800 ppm [LEL] 2,000 ppm 1,000 ppm 3,800 ppm [LEL] 7 ppm 1,000 ppm 100 ppm 50 ppm 3 75 mg/m 100 ppm [Unch] 800 ppm [Unch] 1,900 ppm [LEL] 1,500 ppm 500 ppm 100 ppm 700 ppm 3 800 mg/m 3 500 mg/m 3 250 mg F/m 25 ppm [Unch] 2,000 ppm 20 ppm 30 ppm [Unch] 100 ppm 75 ppm 150 ppm 3 1,250 mg/m 3 50 mg Hf/m 3 35 mg/m 750 ppm 300 ppm [Unch] 3 2 mg/m [Unch] 1,100 ppm [LEL] 1,600 ppm 500 ppm 500 ppm 50 ppm 30 ppm 50 ppm 50 ppm [Unch] 30 ppm [Unch] 75 ppm [Unch] 1 ppm 100 ppm 50 mg/m3 2 ppm 2,500 mg Fe/m3 1,000 ppm 500 ppm 500 ppm 1,300 ppm [LEL]

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Chemical Name

Original IDLH

Revised IDLH

Isobutyl alcohol Isophorone Isopropyl acetate Isopropyl alcohol Isopropylamine Isopropyl ether Isopropyl glycidyl ether Ketene Lead compounds (as Pb) Lindane Lithium hydride L.P.G. Magnesium oxide fume Malathion Maleic anhydride Manganese compounds (as Mn)

8,000 ppm 800 ppm 16,000 ppm 12,000 ppm 4,000 ppm 10,000 ppm 1,000 ppm Unknown 700 mg Pb/m3 1,000 mg/m3 55 mg/m3 19,000 ppm [LEL] N.E. 5,000 mg/m3 Unknown N.E.

1,600 ppm 200 ppm 1,800 ppm 2,000 ppm [LEL] 750 ppm 1,400 ppm [LEL] 400 ppm 5 ppm 100 mg Pb/m3 50 mg/m3 0.5 mg/m3 2,000 ppm [LEL] 750 mg/m3 250 mg/m3 10 mg/m3 500 mg Mn/m3

Mercury compounds [except (organo) alkyls, as Hg] Mercury (organo) alkyl compounds(as Hg) Mesityl oxide Methoxychlor Methyl acetate Methyl acetylene Methyl acetylenepropadiene mixture Methyl acrylate Methylal Methyl alcohol Methylamine Methyl (namyl) ketone Methyl bromide Methyl Cellosolve (r) Methyl Cellosolve (r) acetate Methyl chloride Methyl chloroform Methylcyclohexane Methylcyclohexanol o-Methylcyclohexanone Methylene bisphenyl isocyanate Methylene chloride Methyl formate 5-Methyl 3-heptanone Methyl hydrazine Methyl iodide Methyl isobutyl carbinol Methyl isocyanate Methyl mercaptan Methyl methacrylate Methyl styrene Mica Molybdenum (insoluble compounds, as Mo) Molybdenum (soluble compounds, as Mo) Monomethyl aniline Morpholine

28 mg Hg/m3 10 mg Hg/m3 5,000 ppm N.E. 10,000 ppm 15,000 ppm [LEL] 15,000 ppm 1,000 ppm 15,000 ppm [LEL] 25,000 ppm 100 ppm 4,000 ppm 2,000 ppm 2,000 ppm 4,000 ppm 10,000 ppm 1,000 ppm 10,000 ppm 10,000 ppm 2,500 ppm 100 mg/m3 5,000 ppm 5,000 ppm 3,000 ppm 50 ppm 800 ppm 2,000 ppm 20 ppm 400 ppm 4,000 ppm 5,000 ppm N.E. N.E. N.E. 100 ppm 8,000 ppm

10 mg Hg/m3 2 mg Hg/m3 1,400 ppm [LEL] 5,000 mg/m3 3,100 ppm [LEL] 1,700 ppm [LEL] 3,400 ppm [LEL] 250 ppm 2,200 ppm [LEL] 6,000 ppm 100 ppm [Unch] 800 ppm 250 ppm 200 ppm 200 ppm 2,000 ppm 700 ppm 1,200 ppm [LEL] 500 ppm 600 ppm 75 mg/m3 2,300 ppm 4,500 ppm 100 ppm 20 ppm 100 ppm 400 ppm 3 ppm 150 ppm 1,000 ppm 700 ppm 1,500 mg/m3 5,000 mg Mo/m3 1,000 mg Mo/m3 100 ppm [Unch] 1,400 ppm [LEL]

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Part II: Safety and Best Industry Practices

Chemical Name

Original IDLH

Revised IDLH

Naphtha (coal tar) Naphthalene Nickel carbonyl (as Ni) Nickel metal and other compounds (as Ni) Nicotine Nitric acid Nitric oxide p-Nitroaniline Nitrobenzene p-Nitrochlorobenzene Nitroethane Nitrogen dioxide Nitrogen trifluoride Nitroglycerine Nitromethane 1-Nitropropane 2-Nitropropane Nitrotoluene (oisomer) Nitrotoluene (misomer) Nitrotoluene (p isomers) Octachloronaphthalene Octane Oil mist (mineral)

10,000 ppm [LEL] 500 ppm 7 ppm N.E. 35 mg/m3 100 ppm 100 ppm 300 mg/m3 200 ppm 1,000 mg/m3 1,000 ppm 50 ppm 2,000 ppm 500 mg/m3 1,000 ppm 2,300 ppm 2,300 ppm 200 ppm 200 ppm 200 ppm Unknown 5,000 ppm N.E.

Osmium tetroxide (as Os) Oxalic acid Oxygen difluoride Ozone Paraquat Parathion Pentaborane Pentachloronaphthalene Pentachlorophenol n-Pentane 2-Pentanone Perchloromethyl mercaptan Perchloryl fluoride Petroleum distillates (naphtha) Phenol p-Phenylene diamine Phenyl ether (vapor) Phenyl etherbiphenyl mixture (vapor) Phenyl glycidyl ether Phenylhydrazine Phosdrin Phosgene Phosphine Phosphoric acid Phosphorus (yellow) Phosphorus pentachloride Phosphorus pentasulfide Phosphorus trichloride Phthalic anhydride

1 mg Os/m3 500 mg/m3 0.5 ppm 10 ppm 1.5 mg/m3 20 mg/m3 3 ppm Unknown 150 mg/m3 15,000 ppm [LEL] 5,000 ppm 10 ppm 385 ppm 10,000 ppm 250 ppm Unknown N.E. N.E. Unknown 295 ppm 4 ppm 2 ppm 200 ppm 10,000 mg/m3 N.E. 200 mg/m3 750 mg/m3 50 ppm 10,000 mg/m3

1,000 ppm [LEL] 250 ppm 2 ppm 10 mg Ni/m3 5 mg/m3 25 ppm 100 ppm [Unch] 300 mg/m3 [Unch] 200 ppm [Unch] 100 mg/m3 1,000 ppm [Unch] 20 ppm 1,000 ppm 75 mg/m3 750 ppm 1,000 ppm 100 ppm 200 ppm [Unch] 200 ppm [Unch] 200 ppm [Unch] Unknown [Unch] 1,000 ppm [LEL] 2,500 mg/m3 1 mg Os/m3 [Unch] 500 mg/m3 [Unch] 0.5 ppm [Unch] 5 ppm 1 mg/m3 10 mg/m3 1 ppm Unknown [Unch] 2.5 mg/m3 1,500 ppm [LEL] 1,500 ppm 10 ppm [Unch] 100 ppm 1,100 ppm [LEL] 250 ppm [Unch] 25 mg/m3 100 ppm 10 ppm 100 ppm 15 ppm 4 ppm [Unch] 2 ppm [Unch] 50 ppm 1,000 mg/m3 5 mg/m3 70 mg/m3 250 mg/m3 25 ppm 60 mg/m3

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Chemical Name

Original IDLH

Revised IDLH

Picric acid Pindone Platinum (soluble salts, as Pt) Portland cement Propane n-Propyl acetate n-Propyl alcohol Propylene dichloride Propylene imine Propylene oxide n-Propyl nitrate

100 mg/m3 200 mg/m3 N.E. N.E. 20,000 ppm [LEL] 8,000 ppm 4,000 ppm 2,000 ppm 500 ppm 2,000 ppm 2,000 ppm

Pyrethrum Pyridine Quinone

5,000 mg/m3 3,600 ppm 300 mg/m3

75 mg/m3 100 mg/m3 4 mg Pt/m3 5,000 mg/m3 2,100 ppm [LEL] 1,700 ppm 800 ppm 400 ppm 100 ppm 400 ppm 500 ppm 5,000 mg/m3 [Unch] 1,000 ppm 100 mg/m3

Rhodium (metal fume and insoluble compounds, as Rh) Rhodium (soluble compounds, as Rh) Ronnel Rotenone Selenium compounds (as Se) Selenium hexafluoride Silica, amorphous Silica, crystalline (respirable dust) cristobalite/tridymite: quartz/tripoli: Silver (metal dust and soluble compounds, as Ag) Soapstone Sodium fluoroacetate Sodium hydroxide Stibine Stoddard solvent Strychnine Styrene Sulfur dioxide Sulfuric acid Sulfur monochloride Sulfur pentafluoride Sulfuryl fluoride 2,4,5-T Talc Tantalum (metal and oxide dust, as Ta) TEDP Tellurium compounds (as Te) Tellurium hexafluoride TEPP Terphenyl (o, m, p isomers) 1,1,1,2-Tetrachloro 2,2-difluoroethane 1,1,2,2-Tetrachloro 1,2-difluoroethane 1,1,2,2-Tetrachloroethane Tetrachloroethylene Tetrachloronaphthalene

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N.E. N.E. 5,000 mg/m3 Unknown Unknown 5 ppm N.E. N.E.

100 mg Rh/m3 2 mg Rh/m3 300 mg/m3 2,500 mg/m3 1 mg Se/m3 2 ppm 3,000 mg/m3 25 mg/m3 50 mg/m3

N.E. N.E. 5 mg/m3 250 mg/m3 40 ppm 29,500 mg/m3 3 mg/m3 5,000 ppm 100 ppm 80 mg/m3 10 ppm 1 ppm 1,000 ppm Unknown N.E. N.E. 35 mg/m3 N.E. 1 ppm 10 mg/m3 Unknown 15,000 ppm 15,000 ppm 150 ppm 500 ppm Unknown

10 mg Ag/m3 3,000 mg/m3 2.5 mg/m3 10 mg/m3 5 ppm 20,000 mg/m3 3 mg/m3 [Unch] 700 ppm 100 ppm [Unch] 15 mg/m3 5 ppm 1 ppm [Unch] 200 ppm 250 mg/m3 1,000 mg/m3 2,500 mg Ta/m3 10 mg/m3 25 mg Te/m3 1 ppm [Unch] 5 mg/m3 500 mg/m3 2,000 ppm 2,000 ppm 100 ppm 150 ppm Unknown [Unch]

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Part II: Safety and Best Industry Practices

Chemical Name

Original IDLH

Tetraethyl lead (as Pb) Tetrahydrofuran

40 mg Pb/m3 20,000 ppm [LEL]

Tetramethyl lead (as Pb) Tetramethyl succinonitrile Tetranitromethane Tetryl Thallium (soluble compounds, as Tl) Thiram Tin (inorganic compounds, as Sn) Tin (organic compounds, as Sn) Titanium dioxide Toluene Toluene 2,4-diisocyanate o-Toluidine Tributyl phosphate 1,1,2-Trichloroethane Trichloroethylene Trichloronaphthalene 1,2,3-Trichloropropane 1,1,2-Trichloro 1,2,2-trifluoroethane Triethylamine Trifluorobromomethane 2,4,6-Trinitrotoluene Triorthocresyl phosphate Triphenyl phosphate Turpentine Uranium (insoluble compounds, as U) Uranium (soluble compounds, as U)

Vanadium fume Vinyl toluene Warfarin Xylene (oisomer) Xylene (misomer) Xylene (p isomers) Xylidine Yttrium compounds (as Y) Zinc chloride fume Zinc oxide

40 mg Pb/m3 5 ppm 5 ppm N.E. 20 mg Tl/m3 1,500 mg/m3 400 mg Sn/m3 Unknown N.E. 2,000 ppm 10 ppm 100 ppm 125 ppm 500 ppm 1,000 ppm Unknown 1,000 ppm 4,500 ppm 1,000 ppm 50,000 ppm 1,000 mg/m3 40 mg/m3 N.E. 1,500 ppm 30 mg U/m3 20 mg U/m3 70 mg/m3 (as V2O5) 70 mg/m3 (as V2O5) 5,000 ppm 350 mg/m3 1,000 ppm 1,000 ppm 1,000 ppm 150 ppm N.E. 4,800 mg/m3 2,500 mg/m3

Zirconium compounds (as Zr)

500 mg Zr/m3

Vanadium dust

Revised IDLH 40 mg Pb/m3 [Unch] 2,000 ppm [LEL] 40 mg Pb/m3 [Unch] 5 ppm [Unch] 4 ppm 750 mg/m3 15 mg Tl/m3 100 mg/m3 100 mg Sn/m3 25 mg Sn/m3 5,000 mg/m3 500 ppm 2.5 ppm 50 ppm 30 ppm 100 ppm 1,000 ppm [Unch] Unknown [Unch] 100 ppm 2,000 ppm 200 ppm 40,000 ppm 500 mg/m3 40 mg/m3 [Unch] 1,000 mg/m3 800 ppm 10 mg U/m3 10 mg U/m3 35 mg V/m3 35 mg V/m3 400 ppm 100 mg/m3 900 ppm 900 ppm 900 ppm 50 ppm 500 mg Y/m3 50 mg/m3 500 mg/m3 25 mg Zr/m3

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Table 10A. ACGIH TLV Chemical Name Acetic Acid Acetic Anhydride Acetone Acetonitrile Acetylene tetrabromide Acrolein Aldrin Allyl alcohol Allyl chloride Allyl glycidyl ether Allyl propyl disulfide alpha-Alumina (td) Aluminum, metal (td) 2-Aminopyridine Ammonia Ammonium sulfamate (td) n-Amyl acetate sec-Amyl acetate Aniline and homologs Anisidine o-, p-isomers Antimony & compounds ANTU Arsine Azinphos-methyl Barium, sol. comp. Barium sulfate (td) Benomyl (td) Benzoyl peroxide Benzyl chloride Bismuth telluride undoped (td) Boron oxide (td) Bromine Bromoform 1,3 Butadiene 2-Butanone (MEK) 2-Butoxyethanol n-Butyl-acetate sec-Butyl acetate tert-Butly acetate sec-Butyl alcohol tert-Butyl alcohol n-Butyl glycidyl ether Butyl mercaptan p-tert-Butyl-1-toluene Calcium carbonate (td) Calcium hydroxide (td) Calcium oxide Calcium silicate (td) Calcium sulfate (td) Camphor, synthetic Carbaryl Carbon black

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TLV (ppm)

TLV (mg/m3)

10 5 750 40 1 0.1 0.25 2 1 5 2 10 10 0.5 25 10 100 125 2 0.1 0.5 0.3 0.05 0.2 0.2 10 10 5 1 10 10 0.1 0.5 2 200 25 150 200 200 100 100 25 0.5 1 10 5 2 10 10 12 5 3.5

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Chemical Name Carbon dioxide Carbon Disulfide Carbon monoxide Cellulose (td) Chlorodane Chlorinated camphene Chlorinated diphenyl oxide Chlorine Chlorine dioxide a-chloroacetophenone Chlorobenzene Chlorobromomethane Chlorodiphenyl (42% Cl) Chlorobiphenyl (54% Cl) 1-Chloro-1-nitro- propane Chloropicrin beta-Chloroprene 2-Chloro-6-trichloro- methyl) pyridine (td) Chromium (III) compounds Clopidol (td) Coal tar pitch volatiles Copper fume Copper dusts and mists Cotton dust Cresol, all isomers Crotonaldehyde Cumene Cyclohexane Cyclohexanol Cyclohexanone Cyclohexene Cyclopentadiene 2,4-D Decaborane Demeton Diacetone alcohol Diazomethane Diborane Dibutyl phosphate Dibutyl phthalate o-Dichlorobenzene p-Dichlorobenzene 1,1Dichloroethane 1,2-Dichloroethylene Dichloroethyl ether Dichloromono- fluomethane 1,1 Dichloro-1- nitroethane Dichlorotetra- fluoroethane Dichlorvos (DDVP) Dicyclopentadienyl iron (td) Dieldrin Diethylamine

Part II: Safety and Best Industry Practices TLV (ppm)

TLV (mg/m3)

5000 10 25 10 0.5 0.5 0.5 0.5 0.1 0.05 10 200 1 0.5 2 0.1 10 10 0.5 10 0.2 0.2 1 0.2 5 2 50 300 50 25 300 75 10 0.05 0.01 50 0.2 0.1 1 5 25 10 100 200 5 10 2 1000 0.1 10 0.25 5

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Chemical Name 2-Diethylaminoethanol Difluorodibromomethane Diglycidyl ether (DGE) Diisobutyl ketone Diisopropylamine Dimethyl acetamide Dimethylamine Dimethylaniline (N,N-Dimethylaniline)

TLV (ppm)

3 10 0.01 5 0.1 0.15 0.2 0.15 25 0.2 100

Di-sec octyl phthalate (Di-(2-ethylhexyl) phthalate)

5

Emery (td) Endosulfan Endrin Epichlorohydrin EPN Ethanolamine 2-Ethoxyethanol (Cellosolve) 2-Ethoxyethyl acetate (cellosolve acetate)

3 5 5

Ethyl acetate Ethyl acrylate Ethyl alcohol (Ethanol) Ethylamine Ethyl amyl ketone (5- Methyl-3-heptanone)

400 5 1000 5 25

Ethyl benzene Ethyl bromide Ethyl butyl ketone (3- Heptanone)

100 5 50

Ethyl chloride Ethyl ether Ethyl formate Ethyl mercaptan Ethyl silicate Ferbam (td) Ferrovanadium dust Fluorides (as F) Fluorine Formic acid

100 400 100 0.5 10

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TLV (mg/m3)

2 100 0.1 25 5 10 5 5

Dimethyl-1,2-dibromo- 2,2-dichloroethyl phosphate Dimethylformamide 1,1-Dimethylhydrazine Dimethylphthalate Dimethyl sulfate Dinitrobenzene (all isomers) Dinitro-o-cresol Dinitrotoluene Dioxane (Diethylene dioxide) Diphenyl (Biphenyl) Dipropylene glycol methyl ether

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10 0.1 0.1 2 0.1

10 1 2.5 1 5

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Chemical Name Furfural Furfuryl alcohol Grain dust (oat, wheat, barley) Glycerin (td) Glycidol Graphite, synthetic (td) Gypsum (td) Hafnium Heptachlor Heptane (n-Heptane) Hexachloroethane Hexachloronaph- thalene n-Hexane 2-Hexanone (Methyl n-butyl ketone) Hexone (Methyl isobutyl ketone)

Part II: Safety and Best Industry Practices TLV (ppm) 2 10 4 10 25 2 10 0.5 0.05 400 1 0.2 50 5 50

sec-Hexyl acetate Hydrazine Hydrogen peroxide Hydrogen selenide (as Se) Hydroquinone Iron oxide fume Isoamyl acetate Isoamyl alcohol (primary and secondary)

50 0.01 1 0.05

Isobutyl acetate Isobutyl alcohol Isopropyl acetate Isopropyl alcohol Isopropylamine Isopropyl ether Isopropyl glycidyl ether (IGE) Kaolin (td) Ketene Limestone (td) Lindane Lithium hydride L.P.G. (Liquefied petroleum gas)

150 50 250 400 5 250 50

2 5 100 100

2 0.5 10 0.5 0.025 1000

Magnesite (td) Magnesium oxide fume (total particulate) Malathion (td) Maleic anhydride Manganese compounds (as Mn) Marble (td) Mesityl oxide Methoxychlor (td) 2-Methoxyethanol (Methyl cellosolve)

TLV (mg/m3)

10 10 10 0.25 0.2 10 15 10 5

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Chemical Name

TLV (ppm)

2-Methoxyethyl acetate (Methyl cellosolve acetate)

5

Methyl acetate Methyl acetylene (propyne) Methyl acetylene- propadiene mixture (MAPP)

200 1000 1000

Methyl acrylate Methylal (Dimetoxy- methane) Methyl alcohol Methylamine Methyl n-amyl ketone Methyl bromide Methyl chloroform (1,1,1- Trichloroethane)

10 1000 200 5 50 5 350

Methylcyclohexane Methylcyclohexanol o-Methylcyclohexanone Methylene bisphenyl isocyanate (MDI)

400 50 50 0.005

Methyl formate Methyl hydrazine (Mono- methyl hydrazine)

100 0.01

Methyl iodide Methyl isoamyl ketone Methyl isobutyl carbinol Methyl isocyanate Methyl mercaptan Methyl methacrylate alpha-Methyl styrene Molybdenum (as Mo) Soluble compounds

2 50 25 0.02 0.5 100 50

10 20 10 0.05 1

Nickel, soluble compounds (as Ni) Nicotine Nitric acid Nitric oxide p-Nitroaniline Nitrobenzene p-Nitrochlorobenzene Nitroethane Nitrogen dioxide Nitrogen trifluoride Nitroglycerin Nitromethane 1-Nitropropane 2-Nitropropane

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TLV (mg/m3)

5

Molybdenum (as Mo) Insoluble compounds (td) Morpholine Naphthalene Nickel carbonyl (as Ni) Nickel, metal and insoluble compounds (as Ni)

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0.1 0.5 2 25 3 1 0.1 100 3 10 0.05 20 25 10

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Chemical Name Nitrotoluene (all isomers) Octachloronaphthalene Octane Oil mist, mineral Osmium tetroxide (as Os) Oxalic acid Paraquat (rd) Parathion Particulates not other- wise regulated (PNOR) (td)

Part II: Safety and Best Industry Practices TLV (ppm) 2 0.1 300 5 0.0002 1 0.2 0.1 10

Particulates not other- wise regulated (PNOR) (rf) Pentaborane Pentachloronaphthalene Pentachlorophenol Pentaerythritol (td) Pentane 2-Pentanone (Methyl propyl ketone) Perchloromethyl mercaptan Perchloryl fluoride Perlite (td) Petroleum distillates (Naphtha) (Rubber Solvent) Phenol p-Phenylene diamine Phenyl ether, vapor Phenyl glycidyl ether (PGE) Phenylhydrazine Phosdrin (mevinphos) Phosgene (Carbonyl chloride) Phosphine Phosphoric acid Phosphorus (yellow) Phosphorus pentachloride Phosphorus pentasulfide Phosphorus trichloride Phthalic anhydride Picloram (td) Picric acid Pindone (2-Pivalyl-1, 3-indandione) Plaster of Paris (td) Platinum (as Pt) Soluble salts Portland cement (td) n-Propyl acetate n-Propyl alcohol Propylene dichloride Propylene imine Propylene oxide n-Propyl nitrate Pyrethrum Pyridine

TLV (mg/m3)

3 0.005

0.5 0.5 0.5 10

600 200 0.1 3 10 300 5 0.1 1 0.1 0.1 0.01 0.1 0.3 1 0.02 0.1 1 0.2 1 10 0.1 0.1 10 0.002 10 200 200 75 2 20 25 5 5

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Chemical Name Quinone Rhodium, metal fume and insoluble compounds Rhodium, soluble compounds Ronnel Rotenone Rouge (td) Selenium compounds (as Se) Selenium hexafluoride (as Se) Silicon (td) Silicon carbide (td) Silver, metal and soluble compounds (as Ag) Sodium fluoro- acetate Starch (td) Stibine Stoddard solvent Strychnine Sucrose (td) Sulfur dioxide Sulfur hexafluoride Sulfuric acid Sulfuryl fluoride 2,4,5-T (2,4,5-trichloro- phenoxyacetic acid)

TLV (ppm)

1 0.01 10 5 10 0.2 0.05 10 10 0.01 0.05 10 0.1 100 0.15 10 2 1000 1 5 10 5 0.2 0.1 0.02 10 0.004

1,1,1,2-Tetrachloro-2, 2-difluoroethane

500

1,1,2,2-Tetrachloro-1, 2-difluoroethane

500

1,1,2,2-Tetrachlo- roethane Tetrachloronaph- thalene Tetraethyl lead (as Pb) Tetrahydrofuran Tetramethyl lead (as Pb) Tetramethyl succinonitrile Tetranitromethane Tetryl (2,4,6-Trinitro- phenylmethylni- tramine)

TLV (mg/m3)

0.1

Tantalum, metal and oxide dust TEDP (Sulfotep) Tellurium and com- pounds (as Te) Tellurium hexafluoride (as Te) Temephos (td) TEPP (Tetraethyl pyrophosphate)

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1 2 0.1 200 0.15 0.5 0.005 1.5

Thallium, soluble compounds (as Tl)

0.1

4,4'-Thiobis (6-tert, Butyl-m-cresol) (td)

10

Thiram Tin, inorganic compounds (except oxides) (as Sn)

1 2

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Chemical Name

Part II: Safety and Best Industry Practices TLV (ppm)

Tin, organic com-| pounds (as Sn) Titanium dioxide (td) Toluene-2,4- diisocyanate (TDI) o-Toluidine Tributyl phosphate 1,1,2-Trichloroethane Trichloronaphthalene 1,2,3-Trichloropropane 1,1,2-Trichloro-1,2,2- trifluoroethane Triethylamine Trifluorobromo- methane 2,4,6-Trinitrotoluene (TNT) Triorthocresyl phosphate Triphenyl phosphate Turpentine Uranium (as U) Soluble compounds

TLV (mg/m3) 0.1 10

0.005 2 0.2 10 5 10 1000 1 1000 0.5 0.1 3 100

0.2 0.2

Uranium (as U) Insoluble compounds

0.2

Vanadium (rd) (as V2O5) Vanadium (fume) (as V2O5) Vegetable oil mist (td) Vinyl toluene Warfarin Xylenes (o-, m-, p-isomers) Xylidine Yttrium Zinc chloride fume Zinc oxide fume Zinc oxide (td) Zirconium compounds (as Zr)

0.05 0.05 10 50 0.1 100 0.5 1 1 5 10 5

**Reference: http://www.labsafety.com/refinfo/ezfacts/ezf232.htm

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Nigerian Electricity Health and Safety Standards Table 10B. ACGIH IDLH Chemical Name Acetaldehyde Acetic acid Acetic anhydride Acetone Acetonitrile Acetylene tetrabromide Acrolein Acrylamide Acrylonitrile Aldrin Allyl alcohol Allyl chloride Allyl glycidyl ether 2-Aminopyridine Ammonia Ammonium sulfamate n-Amyl acetate sec-Amyl acetate Aniline o-Anisidine p-Anisidine Antimony compounds (as Sb) ANTU Arsenic (inorganic compounds, as As) Arsine Azinphosmethyl Barium (soluble compounds, as Ba) Benzene Benzoyl peroxide Benzyl chloride

IDLH (ppm) 10000 1000 1000 20000 4000 10 5 unknown 500

100 150 300 270 5 500 5000 4000 9000 100 50 50 80 Sb/m3 100 100 As/m3 6 20 1100 mg Ba/m3 3000 7000 10

Beryllium compounds (as Be) Boron oxide Boron trifluoride Bromine Bromoform 1,3-Butadiene 2-Butanone 2-Butoxyethanol n-Butyl acetate sec-Butyl acetate tert-Butyl acetate

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IDLH (mg/m3)

10 mg Be/m3 no evidence 100 10 unknown 20000 (LEL) 3000 700 10000 10000 10000

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Chemical Name n-Butyl alcohol sec-Butyl alcohol tert-Butyl alcohol n-Butylamine tert-Butyl chromate n-Butyl glycidyl ether n-Butyl mercaptan p-tert-Butyltoluene Cadmium dust (as Cd) Cadmium fume (as Cd) Calcium arsenate (as As) Calcium oxide Camphor (synthetic) Carbaryl Carbon black Carbon dioxide Carbon disulfide Carbon monoxide Carbon tetrachloride Chlordane Chlorinated camphene Chlorinated diphenyl oxide Chlorine Chlorine dioxide Chlorine trifluoride Chloroacetaldehyde alpha-Chloroacetophenone Chlorobenzene o-Chlorobenzylidene malononitrile Chlorobromomethane Chlorodiphenyl (42% chlorine) Chlorodiphenyl (54% chlorine) Chloroform 1-Chloro-1-nitropropane Chloropicrin beta-Chloroprene Chromic acid and chromates Chromium (II) compounds [as Cr(II)] Chromium (III) compounds [as Cr(III)] Chromium metal (as Cr) Coal tar pitch volatiles Cobalt metal, dust and fume (as Co) Copper (dusts and mists, as

Part II: Safety and Best Industry Practices IDLH (ppm) 8000 10000 8000 2000

IDLH (mg/m3)

30 mg CrO3/m3 3500 2500 1000 50 mg Cd/m3 100 mg As/m3 unknown 200 600 no evidence 50000 500 1500 300 500 200 unknown 30 unknown 20 100 100 2400 2 5000 10 1000 2000 4 400 30 (as CrO3) no evidence no evidence no evidence 700 20 mg Co/m3 no

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Chemical Name Cu) Copper fume (as Cu) Cotton dust (raw) Crag (r) herbicide

IDLH (ppm) evidence no evidence no evidence

5000

Cresol (o, m, p isomers)

250

Crotonaldehyde Cumene Cyanides (as CN) Cyclohexane Cyclohexanol Cyclohexanone Cyclohexene Cyclopentadiene 2,4-D

400 8000

DDT Decaborane Demeton Diacetone alcohol Diazomethane Diborane Dibutyl phosphate Dibutyl phthalate o-Dichlorobenzene p-Dichlorobenzene Dichlorodifluoromethane 1,3-Dichloro 5,5dimethylhydantoin 1,1-Dichloroethane 1,2-Dichloroethylene Dichloroethyl ether Dichloromonofluoromethane 1,1-Dichloro 1-nitroethane Dichlorotetrafluoroethane Dichlorvos Dieldrin Diethylamine 2-Diethylaminoethanol Difluorodibromomethane Diglycidyl ether Diisobutyl ketone Diisopropylamine Dimethyl acetamide Dimethylamine

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IDLH (mg/m3)

50 10000 3500 5000 10000 2000 500 no evidence 100 20 2100 2 40 125 9300 1000 1000 50000 unknown 4000 4000 250 50000 150 50000 200 450 2000 500 2500 25 2000 1000 400 2000

Version 1: March 2008

Version 1: March 2008

Chemical Name N,N-Dimethylaniline Dimethyl 1,2-dibromo 2,2dichlorethyl phosphate Dimethylformamide 1,1-Dimethylhydrazine Dimethylphthalate Dimethyl sulfate Dinitrobenzene (o, m, p isomers) Dinitroocresol Dinitrotoluene Di sec-octyl phthalate Dioxane Diphenyl Dipropylene glycol methyl ether Endrin Epichlorohydrin EPN Ethanolamine 2-Ethoxyethanol 2-Ethoxyethyl acetate Ethyl acetate Ethyl acrylate Ethyl alcohol Ethylamine Ethyl benzene Ethyl bromide Ethyl butyl ketone Ethyl chloride Ethylene chlorohydrin Ethylenediamine Ethylene dibromide Ethylene dichloride Ethylene glycol dinitrate Ethyleneimine Ethylene oxide Ethyl ether Ethyl formate Ethyl mercaptan N-Ethylmorpholine Ethyl silicate Ferbam Ferrovanadium dust Fluorides (as F) Fluorine Fluorotrichloromethane Formaldehyde Formic acid

Part II: Safety and Best Industry Practices IDLH (ppm) 100

IDLH (mg/m3) 1800

3500 50 9300 10 200 5 200 unknown 2000 300 unknown 2000 250 50 1000 6000 2500 10000 2000 15000 4000 2000 3500 3000 20000 10 2000 400 1000 500 100 800 19000 (LEL) 8000 2500 2000 1000 no evidence no evidence 500 mg F/m3 25 10000 30 30

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Nigerian Electricity Health and Safety Standards

Chemical Name Furfural Furfuryl alcohol Glycidol Graphite (natural) Hafnium compounds (as Hf) Heptachlor n-Heptane Hexachloroethane Hexachloronaphthalene n-Hexane 2-Hexanone Hexone sec Hexyl acetate Hydrazine Hydrogen bromide Hydrogen chloride Hydrogen cyanide Hydrogen fluoride (as F) Hydrogen peroxide Hydrogen selenide (as Se) Hydrogen sulfide Hydroquinone Iodine Iron oxide dust and fume (as Fe) Isoamyl acetate Isoamyl alcohol (primary) Isoamyl alcohol (secondary) Isobutyl acetate Isobutyl alcohol Isophorone Isopropyl acetate Isopropyl alcohol Isopropylamine Isopropyl ether Isopropyl glycidyl ether Ketene Lead compounds (as Pb) Lindane Lithium hydride L.P.G. Magnesium oxide fume Malathion Maleic anhydride Manganese compounds (as Mn)

II-158

IDLH (ppm) 250 250 500 no evidence unknown

IDLH (mg/m3)

700 5000 300 2 5000 5000 3000 4000 80 50 100 50 30 75 2 300 unknown 10 no evidence 3000 10000 (LEL) 10000 (LEL) 7500 8000 800 16000 12000 4000 10000 1000 unknown 700 mg Pb/m3 1000 55 19000 (LEL) no evidence 5000 unknown no evidence

Version 1: March 2008

Version 1: March 2008

Chemical Name Mercury compounds [except (organo) alkyls, as Hg] Mercury (organo) alkyl compounds(as Hg) Mesityl oxide Methoxychlor Methyl acetate Methyl acetylene Methyl acetylenepropadiene mixture Methyl acrylate Methylal Methyl alcohol Methylamine Methyl (namyl) ketone Methyl bromide Methyl Cellosolve (r) Methyl Cellosolve (r) acetate Methyl chloride Methyl chloroform Methylcyclohexane Methylcyclohexanol o-Methylcyclohexanone Methylene bisphenyl isocyanate Methylene chloride Methyl formate 5-Methyl 3-heptanone Methyl hydrazine Methyl iodide Methyl isobutyl carbinol Methyl isocyanate Methyl mercaptan Methyl methacrylate Methyl styrene Mica Molybdenum (insoluble compounds, as Mo) Molybdenum (soluble compounds, as Mo) Monomethyl aniline Morpholine Naphtha (coal tar) Naphthalene Nickel carbonyl (as Ni) Nickel metal and other compounds (as Ni)

Part II: Safety and Best Industry Practices IDLH (ppm)

IDLH (mg/m3) 28 mg Hg/m3 10 mg Hg/m3

5000 no evidence 10000 15000 (LEL) 15000 1000 15000 (LEL) 25000 100 4000 2000 2000 4000 10000 1000 10000 10000 2500 100 5000 5000 3000 50 800 2000 20 400 4000 5000 no evidence no evidence no evidence 100 8000 10000 (LEL) 500 7 no evidence

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Nigerian Electricity Health and Safety Standards

Chemical Name Nicotine Nitric acid Nitric oxide p-Nitroaniline Nitrobenzene p-Nitrochlorobenzene Nitroethane Nitrogen dioxide Nitrogen trifluoride Nitroglycerine Nitromethane 1-Nitropropane 2-Nitropropane Nitrotoluene (oisomer) Nitrotoluene (misomer) Nitrotoluene (p isomers) Octachloronaphthalene Octane Oil mist (mineral) Osmium tetroxide (as Os) Oxalic acid Oxygen difluoride Ozone Paraquat Parathion Pentaborane Pentachloronaphthalene Pentachlorophenol n-Pentane 2-Pentanone Perchloromethyl mercaptan Perchloryl fluoride Petroleum distillates (naphtha) Phenol p-Phenylene diamine Phenyl ether (vapor) Phenyl etherbiphenyl mixture (vapor) Phenyl glycidyl ether Phenylhydrazine Phosdrin Phosgene Phosphine Phosphoric acid Phosphorus (yellow) Phosphorus pentachloride Phosphorus pentasulfide

II-160

IDLH (ppm)

IDLH (mg/m3) 35

100 100 300 200 1000 1000 50 2000 500 1000 2300 2300 200 200 200 unknown 5000 no evidence 1 mg Os/m3 500 0.5 10 1.5 20 3 unknown 150 15000 (LEL) 5000 10 385 10000 250 unknown no evidence no evidence unknown 295 4 2 200 10000 no evidence 200 750

Version 1: March 2008

Version 1: March 2008

Chemical Name Phosphorus trichloride Phthalic anhydride Picric acid Pindone Platinum (soluble salts, as Pt) Portland cement Propane n-Propyl acetate n-Propyl alcohol Propylene dichloride Propylene imine Propylene oxide n-Propyl nitrate Pyrethrum Pyridine Quinone Rhodium (metal fume and insoluble compounds, as Rh) Rhodium (soluble compounds, as Rh) Ronnel Rotenone Selenium compounds (as Se) Selenium hexafluoride Silica, amorphous Silica, crystalline (respirable dust) cristobalite/tridymite Silica, crystalline (respirable dust) quartz/tripoli: Silver (metal dust as Ag) Silver (soluble compounds as Ag) Soapstone Sodium fluoroacetate Sodium hydroxide Stibine Stoddard solvent Strychnine Styrene Sulfur dioxide Sulfuric acid Sulfur monochloride Sulfur pentafluoride Sulfuryl fluoride 2,4,5-T Talc

Part II: Safety and Best Industry Practices IDLH (ppm) 50

IDLH (mg/m3) 10000 100 200

no evidence no evidence 20000 (LEL) 8000 4000 2000 500 2000 2000 5000 3600 300 no evidence no evidence 5000 unknown unknown 5 no evidence no evidence no evidence no evidence no evidence no evidence 5 250 40 29500 3 5000 100 80 10 1 1000 unknown no

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Chemical Name Tantalum (metal and oxide dust, as Ta) TEDP Tellurium compounds (as Te) Tellurium hexafluoride TEPP Terphenyl (o, m, p isomers) 1,1,1,2-Tetrachloro 2,2difluoroethane 1,1,2,2-Tetrachloro 1,2difluoroethane 1,1,2,2-Tetrachloroethane Tetrachloroethylene Tetrachloronaphthalene Tetraethyl lead (as Pb) Tetrahydrofuran Tetramethyl lead (as Pb) Tetramethyl succinonitrile Tetranitromethane Tetryl Thallium (soluble compounds, as Tl) Thiram Tin (inorganic compounds, as Sn) Tin (organic compounds, as Sn) Titanium dioxide Toluene Toluene 2,4-diisocyanate o-Toluidine Tributyl phosphate 1,1,2-Trichloroethane Trichloroethylene Trichloronaphthalene 1,2,3-Trichloropropane 1,1,2-Trichloro 1,2,2trifluoroethane Triethylamine Trifluorobromomethane 2,4,6-Trinitrotoluene Triorthocresyl phosphate Triphenyl phosphate Turpentine

II-162

IDLH (ppm) evidence no evidence

IDLH (mg/m3)

35 no evidence 1 10 unknown 15000 15000 150 500 2 40 mg Pb/m3 20000 (LEL) 40 mg Pb/m3 5 5 no evidence 20 mg TI/m3 1500 400 mg Sn/m3 unknown no evidence 2000 10 100 125 500 1000 unknown 1000 4500 1000 50000 no evidence 40 no evidence 1500

Version 1: March 2008

Version 1: March 2008

Chemical Name Uranium (insoluble compounds, as U) Uranium (soluble compounds, as U) Vanadium dust Vanadium fume Vinyl toluene Warfarin Xylene (oisomer) Xylene (misomer) Xylene (p isomers) Xylidine Yttrium compounds (as Y) Zinc chloride fume Zinc oxide Zirconium compounds (as Zr)

Part II: Safety and Best Industry Practices IDLH (ppm)

IDLH (mg/m3) 30 mg U/m3 20 mg U/m3 70 70 5000 350 1000 1000 1000

150 no evidence 4800 no evidence 500 mg Zr/m3

http://www.cdc.gov/niosh/idlh/intridl4.html

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Table 10C. ATSDR Minimal Risk Levels (MRLs) December 2006 Chemical Name

Route

Duration

MRL

Factors

Endpoint

Draft/Final

Cover Date

ACENAPHTHENE

Oral

Int.

0.6 mg/kg/day

300

Hepatic

Final

Aug-95

ACETONE

Inh.

Acute Int. Chr. Int.

26 ppm 13 ppm 13 ppm 2 mg/kg/day

9 100 100 100

Neurol. Neurol. Neurol. Hemato.

Final

May-94

Acute Int. Int.

0.003 ppm 0.00004 ppm 0.008 mg/kg/day

100 300 100

Resp. Resp. Gastro.

Draft

5-Sep

Oral ACROLEIN

Inh. Oral

ACRYLONITRILE

Inh. Oral

Acute Acute Int. Chr.

0.1 ppm 0.1 mg/kg/day 0.01 mg/kg/day 0.04 mg/kg/day

10 100 1000 100

Neurol. Develop. Repro. Hemato.

Final

Dec-90

ALDRIN

Oral

Acute Chr.

0.002 mg/kg/day 0.00003 mg/kg/day

1000 1000

Develop. Hepatic

Final

2-Sep

ALUMINUM

Oral

Int. Chr.

1.0 mg/kg/day 1.0 mg/kg/day

30 90

Neurol. Neurol.

Draft

6-Sep

AMERICIUM

Rad.

Acute Chr.

4 mSv/yr 1 mSv/yr

3 3

Develop. Other

Final

4-Oct

AMMONIA

Inh.

Acute Chr.

1.7 ppm 0.1 ppm

30 30

Resp. Resp.

Final

4-Oct

ANTHRACENE

Oral

Int.

10 mg/kg/day

100

Hepatic

Final

Aug-95

ARSENIC *provisional

Oral

Acute* Chr.

0.005 mg/kg/day 0.0003 mg/kg/day

10 3

Gastro. Dermal

Draft

5-Sep

ATRAZINE

Oral

Acute Int.

0.01 mg/kg/day 0.003 mg/kg/day

100 300

Body Wt. Repro.

Final

3-Sep

BARIUM, SOLUBLE SALTS

Oral

Int.

0.7 mg/kg/day

100

Renal

Draft

5-Sep

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Part II: Safety and Best Industry Practices Route

Duration

MRL

Factors

Endpoint

Chr.

0.6 mg/kg/day

100

Renal

Draft/Final

Cover Date

BENZENE

Inh.

Acute Int. Chr.

0.009 ppm 0.006 ppm 0.003 ppm

300 300 10

Immuno. Immuno. Immuno.

Draft

5-Sep

BERYLLIUM

Oral

Chr.

0.002 mg/kg/day

300

Gastro.

Final

2-Sep

BIS(CHLOROMETHYL) ETHER

Inh.

Int.

0.0003 ppm

100

Resp.

Final

Dec-89

BIS(2 CHLOROETHYL) ETHER

Inh.

Int.

0.02 ppm

1000

Body Wt.

Final

Dec-89

BORON

Oral

Int.

0.01 mg/kg/day

1000

Develop.

Final

Jul-92

BROMODICHLOROMETHANE

Oral

Acute Chr.

0.04 mg/kg/day 0.02 mg/kg/day

1000 1000

Hepatic Renal

Final

Dec-89

BROMOFORM

Oral

Acute Int. Chr.

0.7 mg/kg/day 0.2 mg/kg/day 0.02 mg/kg/day

100 300 3000

Hepatic Hepatic Hepatic

Final

5-Sep

BROMOMETHANE

Inh.

0.05 ppm 0.05 ppm 0.005 ppm 0.003 mg/kg/day

100 100 100 100

Neurol. Neurol. Neurol. Gastro.

Final

Sep-92

Oral

Acute Int. Chr. Int.

CADMIUM

Oral

Chr.

0.0002 mg/kg/day

10

Renal

Final

Jul-99

CARBON DISULFIDE

Inh. Oral

Chr. Acute

0.3 ppm 0.01 mg/kg/day

30 300

Neurol. Hepatic

Final

Aug-96

CARBON TETRACHLORIDE

Inh.

Int. Chr. Acute Int.

0.03 ppm 0.03 ppm 0.02 mg/kg/day 0.007 mg/kg/day

30 30 300 100

Hepatic Hepatic Hepatic Hepatic

Final

5-Sep

Acute Chr.

4 mSv 1 mSv/yr

3 3

Develop. Other

Final

4-Oct

Oral

CESIUM

Rad.

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Chemical Name

Route

Duration

MRL

Factors

Endpoint

Draft/Final

Cover Date

CHLORDANE

Inh.

Int. Chr. Acute Int. Chr.

0.0002 mg/m3 0.00002 mg/m3 0.001 mg/kg/day 0.0006 mg/kg/day 0.0006 mg/kg/day

100 1000 1000 100 100

Hepatic Hepatic Develop. Hepatic Hepatic

Final

May-94

Oral

CHLORDECONE

Oral

Acute Int. Chr.

0.01 mg/kg/day 0.0005 mg/kg/day 0.0005 mg/kg/day

100 100 100

Neurol. Renal Renal

Final

Aug-95

CHLORFENVINPHOS

Oral

Acute Int. Chr.

0.002 mg/kg/day 0.002 mg/kg/day 0.0007 mg/kg/day

1000 1000 1000

Neurol. Immuno. Neurol.

Final

Sep-97

CHLORINE DIOXIDE

Inh.

Int.

0.001 ppm

300

Resp.

Final

4-Oct

CHLORITE

Oral

Int.

0.1 mg/kg/day

30

Neurol.

Final

4-Oct

CHLOROBENZENE

Oral

Int.

0.4 mg/kg/day

100

Hepatic

Final

Dec-90

CHLORODIBROMOMETHANE

Oral

Acute Chr.

0.1 mg/kg/day 0.09 mg/kg/day

300 300

Hepatic Hepatic

Final

5-Sep

CHLOROETHANE

Inh.

Acute

15 ppm

100

Develop.

Final

Dec-98

CHLOROFORM

Inh.

Acute Int. Chr. Acute Int. Chr.

0.1 ppm 0.05 ppm 0.02 ppm 0.3 mg/kg/day 0.1 mg/kg/day 0.01 mg/kg/day

30 300 100 100 100 1000

Hepatic Hepatic Hepatic Hepatic Hepatic Hepatic

Final

Sep-97

Oral

CHLOROMETHANE

Inh.

Acute Int. Chr.

0.5 ppm 0.2 ppm 0.05 ppm

100 300 1000

Neurol. Hepatic Neurol.

Final

Dec-98

CHLORPYRIFOS

Oral

Acute

0.003 mg/kg/day

10

Neurol.

Final

Sep-97

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Part II: Safety and Best Industry Practices Route

Duration

MRL

Factors

Endpoint

Int. Chr.

0.003 mg/kg/day 0.001 mg/kg/day

10 100

Neurol. Neurol.

Draft/Final

Cover Date

CHROMIUM(VI), AEROSOL MISTS

Inh.

Int.

0.000005 mg/m3

100

Resp.

Final

Sep-00

CHROMIUM(VI), PARTICULATES

Inh.

Int.

0.001 mg/m3

30

Resp.

Final

Sep-00

COBALT

Inh. Oral Rad.

Chr. Int. Acute Chr.

0.0001 mg/m3 0.01 mg/kg/day 4 mSv 1 mSv/yr

10 100 3 3

Resp. Hemato. Develop. Other

Final

4-Oct

COPPER

Oral

Acute Int.

0.01 mg/kg/day 0.01 mg/kg/day

3 3

Gastro. Gastro.

Final

4-Oct

CRESOLS

Oral

Int.

0.1 mg/kg/day

100

Resp.

Draft

6-Sep

CYANIDE, SODIUM

Oral

Int.

0.05 mg/kg/day

100

Repro.

Final

6-Jul

CYCLOTETRAMETHYLENE TETRANITRAMINE (HMX)

Oral

Acute

0.1 mg/kg/day

1000

Neurol.

Final

Sep-97

Int.

0.05 mg/kg/day

1000

Hepatic

CYCLOTRIMETHYLENETRINITRAMINE (RDX)

Oral

Acute Int.

0.06 mg/kg/day 0.03 mg/kg/day

100 300

Neurol. Repro.

Final

Jun-95

CYHALOTHRIN

Oral

Acute Int.

0.01 mg/kg/day 0.01 mg/kg/day

100 100

Gastro. Gastro.

Final

3-Sep

CYPERMETHRIN

Oral

Acute

0.02 mg/kg/day

100

Neurol.

Final

3-Sep

DDT, P,P'-

Oral

Acute Int.

0.0005 mg/kg/day 0.0005 mg/kg/day

1000 100

Develop. Hepatic

Final

2-Sep

DI(2-ETHYLHEXYL)PHTHALATE

Oral

Int. Chr.

0.1 mg/kg/day 0.06 mg/kg/day

100 100

Repro. Repro.

Final

2-Sep

DI-N-BUTYL PHTHALATE

Oral

Acute

0.5 mg/kg/day

100

Develop.

Final

1-Sep

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Chemical Name

Route

Duration

MRL

Factors

Endpoint

Draft/Final

Cover Date

DI-N-OCTYL PHTHALATE

Oral

Acute Int.

3 mg/kg/day 0.4 mg/kg/day

300 100

Hepatic Hepatic

Final

Sep-97

DIAZINON

Inh. Oral

Int. Acute Int. Chr.

0.01 mg/m3 0.006 mg/kg/day 0.002 mg/kg/day 0.0007 mg/kg/day

30 100 100 100

Neurol. Neurol. Neurol. Neurol.

Draft

6-Sep

DICHLOROBENZENE, 1,2-

Oral

Acute Int. Chr.

0.7 mg/kg/day 0.6 mg/kg/day 0.3 mg/kg/day

100 100 100

Hepatic Hepatic Renal

Final

6-Jul

DICHLOROBENZENE, 1,3-

Oral

Acute Int.

0.4 mg/kg/day 0.02 mg/kg/day

100 100

Hepatic Endocr.

Final

6-Jul

DICHLOROBENZENE, 1,4-

Inh.

Acute Int. Chr. Int. Chr.

2 ppm 0.2 ppm 0.01 ppm 0.07 mg/kg/day 0.07 mg/kg/day

10 100 30 100 100

Ocular Hepatic Resp. Hepatic Hepatic

Final

6-Jul

Acute Int. Chr. Acute Int. Chr.

0.002 ppm 0.0003 ppm 0.00006 ppm 0.004 mg/kg/day 0.003 mg/kg/day 0.0005 mg/kg/day

100 100 100 1000 10 100

Neurol. Neurol. Neurol. Neurol. Neurol. Neurol.

Final

Sep-97

Oral

DICHLORVOS

Inh.

Oral

DIELDRIN

Oral

Int. Chr.

0.0001 mg/kg/day 0.00005 mg/kg/day

100 100

Neurol. Hepatic

Final

2-Sep

DIETHYL PHTHALATE

Oral

Acute Int.

7 mg/kg/day 6 mg/kg/day

300 300

Repro. Hepatic

Final

Jun-95

DIISOPROPYL METHYLPHOSPHONATE (DIMP)

Oral

Int. Chr.

0.8 mg/kg/day 0.6 mg/kg/day

100 100

Hemato. Hemato.

Final

Oct-98

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Part II: Safety and Best Industry Practices

Chemical Name

Route

Duration

MRL

Factors

Endpoint

Draft/Final

Cover Date

DISULFOTON

Inh.

Acute Int. Acute Int. Chr.

0.006 mg/m3 0.0002 mg/m3 0.001 mg/kg/day 0.00009 mg/kg/day 0.00006 mg/kg/day

30 30 100 100 1000

Neurol. Neurol. Neurol. Develop. Neurol.

Final

Aug-95

Oral

ENDOSULFAN

Oral

Int. Chr.

0.005 mg/kg/day 0.002 mg/kg/day

100 100

Immuno. Hepatic

Final

Sep-00

ENDRIN

Oral

Int. Chr.

0.002 mg/kg/day 0.0003 mg/kg/day

100 100

Neurol. Neurol.

Final

Aug-96

ETHION

Oral

Acute Int. Chr.

0.002 mg/kg/day 0.002 mg/kg/day 0.0004 mg/kg/day

30 30 150

Neurol. Neurol. Neurol.

Final

Sep-00

ETHYLBENZENE

Inh.

Int.

1.0 ppm

100

Develop.

Final

Jul-99

ETHYLENE GLYCOL

Inh. Oral

Acute Acute Chr.

0.5 ppm 2.0 mg/kg/day 2.0 mg/kg/day

100 100 100

Renal Develop. Renal

Final

Sep-97

ETHYLENE OXIDE

Inh.

Int.

0.09 ppm

100

Renal

Final

Dec-90

FLUORANTHENE

Oral

Int.

0.4 mg/kg/day

300

Hepatic

Final

Aug-95

FLUORENE

Oral

Int.

0.4 mg/kg/day

300

Hepatic

Final

Aug-95

FLUORIDE, SODIUM

Oral

Chr.

0.05 mg/kg/day

3

Musculo.

Final

3-Sep

FLUORINE

Inh.

Acute

0.01 ppm

10

Resp.

Final

3-Sep

FORMALDEHYDE

Inh.

Acute Int. Chr. Int. Chr.

0.04 ppm 0.03 ppm 0.008 ppm 0.3 mg/kg/day 0.2 mg/kg/day

9 30 30 100 100

Resp. Resp. Resp. Gastro. Gastro.

Final

Jul-99

Oral

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Chemical Name

Route

Duration

MRL

Factors

Endpoint

Draft/Final

Cover Date

FUEL OIL NO.2

Inh.

Acute

0.02 mg/m3

1000

Neurol.

Final

Jun-95

GUTHION

Inh.

Acute Int. Chr. Acute Int. Chr.

0.02 mg/m3 0.01 mg/m3 0.01 mg/m3 0.01 mg/kg/day 0.003 mg/kg/day 0.003 mg/kg/day

30 30 30 100 100 100

Neurol. Neurol. Neurol. Neurol. Neurol. Neurol.

Draft

6-Sep

Oral

HEPTACHLOR

Oral

Int.

0.0001 mg/kg/day

300

Immuno.

Draft

5-Sep

HEXACHLOROBENZENE

Oral

Acute Int. Chr.

0.008 mg/kg/day 0.0001 mg/kg/day 0.00005 mg/kg/day

300 90 300

Develop. Repro. Develop.

Final

2-Sep

HEXACHLOROBUTADIENE

Oral

Int.

0.0002 mg/kg/day

1000

Renal

Final

May-94

HEXACHLOROCYCLOHEXANE, ALPHA-

Oral

Chr.

0.008 mg/kg/day

100

Hepatic

Final

5-Sep

HEXACHLOROCYCLOHEXANE, BETA-

Oral

Acute Int.

0.05 mg/kg/day 0.0006 mg/kg/day

100 300

Neurol. Hepatic

Final

5-Sep

HEXACHLOROCYCLOHEXANE, GAMMA-

Oral

Acute Int.

0.003 mg/kg/day 0.00001 mg/kg/day

300 1000

Develop. Immuno.

Final

5-Sep

HEXACHLOROCYCLOPENTADIENE

Inh.

Int. Chr. Int.

0.01 ppm 0.0002 ppm 0.1 mg/kg/day

30 90 100

Resp. Resp. Renal

Final

Jul-99

Acute Int. Acute Int.

6 ppm 6 ppm 1 mg/kg/day 0.01 mg/kg/day

30 30 100 100

Neurol. Neurol. Hepatic Hepatic

Final

Sep-97

Oral HEXACHLOROETHANE

Inh. Oral

HEXAMETHYLENE DIISOCYANATE

Inh.

Int. Chr.

0.00003 ppm 0.00001 ppm

30 90

Resp. Resp.

Final

Oct-98

HEXANE, N-

Inh.

Chr.

0.6 ppm

100

Neurol.

Final

Jul-99

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Chemical Name

Route

Duration

MRL

Factors

Endpoint

Draft/Final

Cover Date

HYDRAZINE

Inh.

Int.

0.004 ppm

300

Hepatic

Final

Sep-97

HYDROGEN FLUORIDE

Inh.

Acute

0.02 ppm

30

Resp.

Final

3-Sep

HYDROGEN SULFIDE

Inh.

Acute Int.

0.07 ppm 0.02 ppm

27 30

Resp. Resp.

Final

6-Jul

IODIDE

Oral

Acute Chr.

0.01 mg/kg/day 0.01 mg/kg/day

1 1

Endocr. Endocr.

Final

4-Oct

IONIZING RADIATION, N.O.S.

Rad.

Acute Chr.

4 mSv 1 mSv/yr

3 3

Neurol. Other

Final

Sep-99

ISOPHORONE

Oral

Int. Chr.

3 mg/kg/day 0.2 mg/kg/day

100 1000

Other Hepatic

Final

Dec-89

JP-4

Inh.

Int.

9 mg/m3

300

Hepatic

Final

Jun-95

JP-5/JP-8

Inh.

Int.

3 mg/m3

300

Hepatic

Final

Oct-98

JP-7

Inh.

Chr.

0.3 mg/m3

300

Hepatic

Final

Jun-95

KEROSENE

Inh.

Int.

0.01 mg/m3

1000

Hepatic

Final

Jun-95

MALATHION

Inh.

Acute Int. Int. Chr.

0.2 mg/m3 0.02 mg/m3 0.02 mg/kg/day 0.02 mg/kg/day

100 1000 10 100

Neurol. Resp. Neurol. Neurol.

Final

3-Sep

Oral

MANGANESE

Inh.

Chr.

0.00004 mg/m3

500

Neurol.

Final

Sep-00

MERCURIC CHLORIDE

Oral

Acute Int.

0.007 mg/kg/day 0.002 mg/kg/day

100 100

Renal Renal

Final

Mar-99

MERCURY

Inh.

Chr.

0.0002 mg/m3

30

Neurol.

Final

Mar-99

METHOXYCHLOR

Oral

Int.

0.005 mg/kg/day

1000

Repro.

Draft

Sep-00

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Chemical Name

Route

Duration

MRL

Factors

Endpoint

Draft/Final

Cover Date

METHYL PARATHION

Oral

Int. Chr.

0.0007 mg/kg/day 0.0003 mg/kg/day

300 100

Neurol. Hemato.

Final

1-Sep

METHYL-T-BUTYL ETHER

Inh.

Acute Int. Chr. Acute Int.

2 ppm 0.7 ppm 0.7 ppm 0.4 mg/kg/day 0.3 mg/kg/day

100 100 100 100 300

Neurol. Neurol. Renal Neurol. Hepatic

Final

Aug-96

Acute Int. Chr. Acute Chr.

0.6 ppm 0.3 ppm 0.3 ppm 0.2 mg/kg/day 0.06 mg/kg/day

100 90 30 100 100

Neurol. Hepatic Hepatic Neurol. Hepatic

Final

Sep-00

Oral

METHYLENE CHLORIDE

Inh.

Oral

METHYLMERCURY

Oral

Chr.

0.0003 mg/kg/day

4

Develop.

Final

Mar-99

MIREX

Oral

Chr.

0.0008 mg/kg/day

100

Hepatic

Final

Aug-95

N-NITROSODI-N-PROPYLAMINE

Oral

Acute

0.095 mg/kg/day

100

Hepatic

Final

Dec-89

NAPHTHALENE

Inh.

Chr.

0.0007 ppm

300

Resp.

Final

5-Sep

Oral

Acute Int.

0.6 mg/kg/day 0.6 mg/kg/day

90 90

Neurol. Neurol.

NICKEL

Inh.

Int. Chr.

0.0002 mg/m3 0.00009 mg/m3

30 30

Resp. Resp.

Final

5-Sep

PENTACHLOROPHENOL

Oral

Acute Int. Chr.

0.005 mg/kg/day 0.001 mg/kg/day 0.001 mg/kg/day

1000 1000 1000

Develop. Repro. Endocr.

Final

1-Sep

PERCHLORATES

Oral

Chr.

0.0007 mg/kg/day

10

Endocr.

Draft

5-Sep

PERMETHRIN

Oral

Acute Int.

0.3 mg/kg/day 0.2 mg/kg/day

100 100

Neurol. Neurol.

Final

3-Sep

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Chemical Name

Route

Duration

MRL

Factors

Endpoint

Draft/Final

Cover Date

PHENOL

Inh. Oral

Acute Acute

0.02 ppm 0.6 mg/kg/day

30 100

Resp. Body Wt.

Draft

6-Sep

PHOSPHORUS, WHITE

Inh. Oral

Acute Int.

0.02 mg/m3 0.0002 mg/kg/day

30 100

Resp. Repro.

Final

Sep-97

POLYBROMINATED BIPHENYLS (PBBs)

Oral

Acute

0.01 mg/kg/day

100

Endocr.

Final

4-Oct

POLYBROMINATED DIPHENYL ETHERS (PBDEs), LOWER BROMINATED

Inh

Int.

0.006 mg/m3

90

Endocr.

Final

4-Oct

Oral

Acute Int.

0.03 mg/kg/day 0.007 mg/kg/day

30 300

Endocr. Hepatic

PBDE, DECABROMINATED

Oral

Int.

10 mg/kg/day

100

Develop.

Final

4-Oct

POLYCHLORINATED BIPHENYLS (PCBs) (Aroclor 1254)

Oral

Int.

0.03 ug/kg/day

300

Neurol.

Final

Nov-00

Chr.

0.02 ug/kg/day

300

Immuno.

PROPYLENE GLYCOL DINITRATE

Inh.

Acute Int. Chr.

0.003 ppm 0.00004 ppm 0.00004 ppm

10 1000 1000

Neurol. Hemato. Hemato.

Final

Jun-95

PROPYLENE GLYCOL

Inh.

Int.

0.009 ppm

1000

Resp.

Final

Sep-97

REFRACTORY CERAMIC FIBERS

Inh.

Chr.

0.03 fibers/cc

30

Resp.

Final

4-Oct

SELENIUM

Oral

Chr.

0.005 mg/kg/day

3

Dermal

Final

3-Sep

STRONTIUM

Oral

Int.

2 mg/kg/day

30

Musculo.

Final

4-Oct

STYRENE

Inh. Oral

Chr. Int.

0.06 ppm 0.2 mg/kg/day

100 1000

Neurol. Hepatic

Final

Sep-92

SULFUR DIOXIDE

Inh.

Acute

0.01 ppm

9

Resp.

Final

Dec-98

SULFUR MUSTARD

Inh.

Acute

0.0007 mg/m3

30

Ocular

Final

3-Sep

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Nigerian Electricity Health and Safety Standards Chemical Name

Version 1: March 2008

Route

Duration

MRL

Factors

Endpoint

Oral

Int. Acute Int.

0.00002 mg/m3 0.5 µg/kg/day 0.07 µg/kg/day

30 1000 300

Ocular Develop. Gastro.

Oral

Acute Chr. Acute

0.2 ppm 0.04 ppm 0.05 mg/kg/day

10 100 100

TIN, INORGANIC

Oral

Int.

0.3 mg/kg/day

TIN, DIBUTYL-

Oral

Int.

TIN, TRIBUTYL-

Oral

TITANIUM TETRACHLORIDE

TOLUENE

TETRACHLOROETHYLENE

Draft/Final

Cover Date

Neurol. Neurol. Develop.

Final

Sep-97

100

Hemato.

Final

5-Sep

0.005 mg/kg/day

1000

Immunol.

Final

39330

Int. Chr.

0.0003 mg/kg/day 0.0003 mg/kg/day

100 100

Immunol. Immunol.

Final

5-Sep

Inh.

Int. Chr.

0.01 mg/m3 0.0001 mg/m3

90 90

Resp. Resp.

Final

Sep-97

Inh.

Acute Chr. Acute Int.

1 ppm 0.08 ppm 0.8 mg/kg/day 0.02 mg/kg/day

10 100 300 300

Neurol. Neurol. Neurol. Neurol.

Final

Sep-00

Inh.

Oral

TOXAPHENE

Oral

Acute Int.

0.005 mg/kg/day 0.001 mg/kg/day

1000 300

Hepatic Hepatic

Final

Aug-96

TRICHLOROETHYLENE

Inh.

Acute Int. Acute

2 ppm 0.1 ppm 0.2 mg/kg/day

30 300 300

Neurol. Neurol. Develop.

Final

Sep-97

0.0004 mg/m3 0.0003 mg/m3 0.002 mg/kg/day

90 30 30

Renal Renal Renal

Final

Sep-99

Oral

Int. Chr. Int.

URANIUM, INSOLUBLE COMPOUNDS

Inh.

Int.

0.008 mg/m3

30

Renal

Final

Sep-99

VANADIUM

Inh. Oral

Acute Int.

0.0002 mg/m3 0.003 mg/kg/day

100 100

Resp. Renal

Final

Jul-92

Oral URANIUM, HIGHLY SOLUBLE SALTS

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Part II: Safety and Best Industry Practices

Chemical Name

Route

Duration

MRL

Factors

Endpoint

Draft/Final

Cover Date

VINYL ACETATE

Inh.

Int.

0.01 ppm

100

Resp.

Final

Jul-92

VINYL CHLORIDE

Inh.

Acute Int. Chr.

0.5 ppm 0.03 ppm 0.003 mg/kg/day

30 30 30

Develop. Hepatic Hepatic

Final

6-Jul

Acute Int. Chr. Acute Int. Chr.

2 ppm 0.6 ppm 0.05 ppm 1 mg/kg/day 1 mg/kg/day 0.6 mg/kg/day

30 90 300 100 300 300

Neurol. Neurol. Neurol. Neurol. Neurol. Neurol.

Draft

5-Sep

Oral XYLENES, MIXED

Inh.

Oral

ZINC

Oral

Int. Chr.

0.3 mg/kg/day 0.3 mg/kg/day

3 3

Hemato. Hemato.

Final

5-Sep

1-METHYLNAPHTHALENE

Oral

Chr.

0.07 mg/kg/day

1000

Resp.

Final

5-Sep

2-METHYLNAPHTHALENE

Oral

Chr.

0.04 mg/kg/day

100

Resp.

Final

5-Sep

1,1-DICHLOROETHENE

Inh. Oral

Int. Chr.

0.02 ppm 0.009 mg/kg/day

100 1000

Hepatic Hepatic

Final

May-94

1,1-DIMETHYLHYDRAZINE

Inh.

Int.

0.0002 ppm

300

Hepatic

Final

Sep-97

1,1,1-TRICHLOROETHANE

Inh.

Acute Int. Int.

2 ppm 0.7 ppm 20 mg/kg/day

100 100 100

Neurol. Neurol. Body Wt.

Final

6-Jul

Oral 1,1,2-TRICHLOROETHANE

Oral

Acute Int.

0.3 mg/kg/day 0.04 mg/kg/day

100 100

Neurol. Hepatic

Final

Dec-89

1,1,2,2-TETRACHLOROETHANE

Oral

Int.

0.5 mg/kg/day

100

Hepatic

Draft

6-Sep

1,2-DIBROMO-3-CHLOROPROPANE

Inh. Oral

Int. Int.

0.0002 ppm 0.002 mg/kg/day

100 1000

Repro. Repro.

Final

Sep-92

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Chemical Name

Route

Duration

MRL

Factors

Endpoint

Draft/Final

Cover Date

1,2-DICHLOROETHANE

Inh. Oral

Chr. Int.

0.6 ppm 0.2 mg/kg/day

90 300

Hepatic Renal

Final

1-Sep

1,2-DICHLOROETHENE, CIS-

Oral

Acute Int.

1 mg/kg/day 0.3 mg/kg/day

100 100

Hemato. Hemato.

Final

Aug-96

1,2-DICHLOROETHENE, TRANS-

Inh.

Acute Int. Int.

0.2 ppm 0.2 ppm 0.2 mg/kg/day

1000 1000 100

Hepatic Hepatic Hepatic

Final

Aug-96

0.05 ppm 0.007 ppm 0.1 mg/kg/day 0.07 mg/kg/day 0.09 mg/kg/day

1000 1000 1000 1000 1000

Resp. Resp. Neurol. Hemato. Hepatic

Final

Dec-89

Oral

Acute Int. Acute Int. Chr.

1,2-DIMETHYLHYDRAZINE

Oral

Int.

0.0008 mg/kg/day

1000

Hepatic

Final

Sep-97

1,2,3-TRICHLOROPROPANE

Inh. Oral

Acute Int.

0.0003 ppm 0.06 mg/kg/day

100 100

Resp. Hepatic

Final

Sep-92

1,3-DICHLOROPROPENE

Inh.

Int. Chr. Int. Chr.

0.008 ppm 0.007 ppm 0.04 mg/kg/day 0.03 mg/kg/day

30 30 100 100

Resp. Resp. Gastro. Gastro.

Draft

6-Sep

Oral 1,2-DICHLOROPROPANE

Inh.

Oral

1,3-DINITROBENZENE

Oral

Acute Int.

0.008 mg/kg/day 0.0005 mg/kg/day

100 1000

Repro. Hemato.

Final

Jun-95

1,4-DIOXANE

Inh.

Acute Int. Chr. Acute Int. Chr.

2 ppm 1 ppm 1 ppm 4 mg/kg/day 0.6 mg/kg/day 0.1 mg/kg/day

30 30 30 100 100 100

Ocular Hepatic Hepatic Resp. Hepatic Hepatic

Final

6-Jul

Acute Int.

6 ppm 3 ppm

9 9

Hemato. Hemato.

Final

Oct-98

Oral

2-BUTOXYETHANOL

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Inh.

Version 1: March 2008 Chemical Name

Part II: Safety and Best Industry Practices Route

Duration

MRL

Factors

Endpoint

Draft/Final

Cover Date

Oral

Chr. Acute Int.

0.2 ppm 0.4 mg/kg/day 0.07 mg/kg/day

3 90 1000

Hemato. Hemato. Hepatic

2,3-DICHLOROPROPENE

Inh.

Acute

0.002 ppm

90

Resp.

Draft

6-Sep

2,3,4,7,8-PENTACHLORO-DIBENZOFURAN

Oral

Acute Int.

0.001 ug/kg/day 0.00003 ug/kg/day

3000 3000

Immuno. Hepatic

Final

May-94

2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN

Oral

Acute Int. Chr.

0.0002 ug/kg/day 0.00002 ug/kg/day 0.000001 ug/kg/day

21 30 90

Immuno. Lymphor. Develop.

Final

Dec-98

2,4-DICHLOROPHENOL

Oral

Int.

0.003 mg/kg/day

100

Immuno.

Final

Jul-99

2,4-DINITROPHENOL

Oral

Acute

0.01 mg/kg/day

100

Body Wt.

Final

Aug-95

2,4-DINITROTOLUENE

Oral

Acute Chr.

0.05 mg/kg/day 0.002 mg/kg/day

100 100

Neurol. Hemato.

Final

Dec-98

2,4,6-TRINITROTOLUENE

Oral

Int.

0.0005 mg/kg/day

1000

Hepatic

Final

Jun-95

2,6-DINITROTOLUENE

Oral

Int.

0.004 mg/kg/day

1000

Hemato.

Final

Dec-98

4-CHLOROPHENOL

Oral

Acute

0.01 mg/kg/day

100

Hepatic

Final

Jul-99

4,4'-METHYLENEBIS(2-CHLOROANILINE)

Oral

Chr.

0.003 mg/kg/day

3000

Hepatic

Final

May-94

4,4'-METHYLENEDIANILINE

Oral

Acute Int.

0.2 mg/kg/day 0.08 mg/kg/day

300 100

Hepatic Hepatic

Final

Oct-98

4,6-DINITRO-O-CRESOL

Oral

Acute Int.

0.004 mg/kg/day 0.004 mg/kg/day

100 100

Neurol. Neurol.

Final

Aug-95

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SEC. 2(f) JOB HAZARDS ANALYSIS ASSESSMENT CONTENTS 2(f)(1) Introduction ...............................................................................................................II-181 2(f)(2) Responsibility and Tailgate Meetings......................................................................II-181 2(f)(3) Hazards Assessment..................................................................................................II-182 2(f)(3)(i) Purpose of Hazards Assessment........................................................................... II-182 2(f)(3)(ii) Instructions and Forms for Job Hazard Analysis Assessment for PPE............... II-183 2(f)(3)(iii) General Provisions for Performing Safety Inspections ...................................... II-188 2(f)(3)(iv) Inspection Preparation ........................................................................................ II-189 2(f)(3)(v) Hazard Classification........................................................................................... II-189 2(f)(3)(vi) Inspection Equipment......................................................................................... II-190 2(f)(3)(vii) Inspection Process ............................................................................................. II-190 2(f)(3)(viii) Closeout Review .............................................................................................. II-191 2(f)(3)(ix) Abatement Plan .................................................................................................. II-191 2(f)(4) Hazard Assessment and PPE Checklists.................................................................II-191 2(f)(5) Bibliography ..............................................................................................................II-200

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2(f)(1) Introduction A job hazard analysis must accompany all project workplans. A job hazard analysis identifies hazards associated with work projects and worksites, and identifies protective equipment, modified work procedures, managerial controls and personal protective equipment needed. Line officers and staff shall use the job hazard analysis to monitor the safety performance of work supervisors, crews or contractors. It serves as the standard against which actual safety performance is measured. 2(f)(2) Responsibility and Tailgate Meetings The person responsible for preparing project work plans, specified HSE Officers, shall complete a Job Hazard Analysis Form. A recommended Job Hazard Analysis Form is provided in Sec.2(f)(3). A line officer shall approve the job hazard analysis. Work supervisors shall discuss the job hazards with crew members prior to beginning new projects or changing work sites. Identify any hazards not noted on the job hazard analysis. Discuss ways to reduce these hazards, including the use of protective equipment. Document these meetings. File documentation with other project work documents when the project is completed. Exhibit 1 is a suggested format for a work supervisor's tailgate safety meeting. Exhibit 1 WORK SUPERVISOR’S TAILGATE MEETINGS Instructions To be completed by first line supervisor or work leader at the worksite prior to beginning job and when the hazards change due to a change in worksite location or other condition. Add any hazards that do not appear on the Job Hazard Analysis Form (see Sec.2(f)(3)). Reference the Nigerian Electricity Health and Safety Codes to help identify recommended work procedures and protective equipment. Study/Project/Job _________________ Work Leader/Supervisor ________________ Describe Work: _______________________________________________________________________ _____________________________________________________________________ ______________________________________________________________________ Identify & List Hazards; Hazard Reducing Work Procedures Discussed With Crew: _______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ II-181

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Protective Equipment Required by: ________________________________________________________________________ _______________________________________________________________________ Additional Protective Equipment Needed: _______________________________________________________________________ _______________________________________________________________________ Start of Project (date) ________________ Discussed with Crew (date) _______________ To be filed at end of project with other project documents. Signature of Work Supervisor: _________________________ Date: _______________ End 2(f)(3) Hazards Assessment 2(f)(3)(i) Purpose of Hazards Assessment A hazard assessment is an important element of a personal protective equipment (PPE) program because it produces the information needed to select the appropriate PPE for any hazards present or likely to be present at particular workplaces. Employer must have adequate capacity/capability of determining and evaluating the hazards of a particular workplace. The hazard assessment itself should be viewed as a performance-oriented provision that simply requires management to use their awareness of workplace hazards to enable them to select the appropriate PPE for the work being performed. Examples of equipment required to be provided by employers include but are not limited to: • • • • • • • •

II-182

Welding or wire mesh gloves; Respirators; Hard hats; Specialty glasses and goggles such as those used for laser and ultraviolet radiation protection; Specialty foot protection such as metatarsal shoes and lineman's shoes with built-in gaffs [such as those used for climbing]; Face shields; Rubber gloves, blankets, cover-ups; and Hot sticks and other live-line tools used by power generation workers.

Version 1: March 2008

Part II: Safety and Best Industry Practices

The Nigerian Electricity Health and Safety Standards require the use of personal protective equipment (PPE) to reduce employees' exposures to hazards when engineering the administrative controls are not feasible or effective in reducing these exposures to acceptable levels. Employers are required to determine all exposures to hazards in their workplace and determine if PPE should be used to protect their workers. If PPE is to be used to reduce the exposure of employees to hazards, a PPE program should be initialized and maintained. The program should contain identification and evaluation of hazards in the workplace and define whether PPE is an appropriate control measure; if PPE is to be used, how it is selected, maintained and its use evaluated; training of employees using the PPE; and vigilance of the program to determine its effectiveness in preventing employee injury or illness. Other sections of the Nigerian Electricity Health and Safety Standards provide general provisions and specific guidance on: • • • • • • •

General safety requirements Eye and face protection Respiratory protection Head protection Foot protection Hand protection Personal protective equipment.

The following is a recommended approach to conducting a hazard assessment for PPE. The approach also helps to assign a Risk Priority Code to the hazard to determine the course of actions needed to take to control the hazard. Follow the instructions as you conduct the hazard assessment and fill in the hazard assessment form. You can make copies of the form or customize it to fit the needs of the work place. This tool can also serve as written certification that a hazard assessment has been performed. Document the hazard assessment for PPE. Make sure that the blank fields at the bottom of the form (indicated by *) are filled out. * Name of your work place * Address of the work place where you are doing the hazard assessment * Name of person certifying that a workplace hazard assessment was done * Date the hazard assessment was done 2(f)(3)(ii) Instructions and Forms for Job Hazard Analysis Assessment for PPE The following is a recommended step by step approach to conducting the job hazard analysis assessment for PPE. Step 1. Conduct a walk through survey of the work area. For each job/task step, note the presence of any of the hazard types listed in Table 1, their sources, and the body parts at risk. Fill out the left side of the hazard assessment form. Collect all the information you can. Note that this is a generalized approach. The table may be expanded or modified as appropriate. In collecting the information, bear the following in mind: II-183

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• • •

Version 1: March 2008

Look at all steps of a job and ask the employee if there are any variations in the job that are infrequently done and that you might have missed during your observation. For purposes of the assessment, assume that no PPE is being worn by the affected employees even though they may actually be wearing what they need to do the job safely. Note all observed hazards. This list in Table 11 does not cover all possible hazards that employees may face or for which personal protective equipment may be required. Noisy environments or those which may require respirators must be evaluated with appropriate test equipment to quantify the exposure level when overexposure is suspected.

Table 11. List of typical workplace hazards.

Type Hazard Impact Penetration

General Description of Hazard Type Person can strike an object or be struck by a moving or flying or falling object. Person can strike, be struck by, or fall upon an object or tool that would break the skin. Crush or pinch An object(s) or machine may crush or pinch a body or body part. Harmful Dust Presence of dust that may cause irritation, or breathing or vision difficulty. May also have ignition potential. Exposure from spills, splashing, or other contact with chemical substances or Chemical harmful dusts that could cause illness, irritation, burns, asphyxiation, breathing or vision difficulty, or other toxic health effects. May also have ignition potential. Heat Exposure to radiant heat sources, splashes or spills of hot material, or work in hot environments. Light (optical) Radiation Exposure to strong light sources, glare, or intense light exposure which is a byproduct of a process. Electrical Contact Exposure to contact with or proximity to live or potentially live electrical objects. Ergonomic hazards Repetitive movements, awkward postures, vibration, heavy lifting, etc. Environmental hazards Conditions in the work place that could cause discomfort or negative health effects.

Step 2. Analyze the hazard. For each job task with a hazard source identified, use the Job Hazard Analysis Matrix table (Table 12) and review the hazard with the affected employee and supervisor. Fill out the right side of the hazard assessment form: • • •

II-184

Rate the SEVERITY of injury that would reasonably be expected to result from exposure to the hazard. Assign a PROBABILITY of an accident actually happening. Assign a RISK CODE based upon the intersection of the SEVERITY and PROBABILITY ratings on the matrix.

Version 1: March 2008

Part II: Safety and Best Industry Practices

Table 12. Job Hazard Analysis Matrix and Risk Priority Factors.

Job Hazard Analysis Matrix Severity of Injury Level Description

Probability of an Accident Occurring B C A Frequent

I II III IV

Fatal or Permanent Disability Severe Illness or Injury Minor Injury or Illness No Injury or Illness

Risk Priority Code Risk Level 1 High 2

Medium

3

Low

1 1 2 3

Several Times 1 1 2 3

Occasional 1 2 2-3 3

2 2 3 3

D

E

Possible

Extremely Improbable 3 3 3 3

Action Required Work activities must be suspended immediately until hazard can be eliminated or controlled or reduced to a lower level. Job hazards are unacceptable and must be controlled by engineering, administrative, or personal protective equipment methods as soon as possible. No real or significant hazard exists. Controls are not required but may increase the comfort level of employees.

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Step 3. Take action on the assessment. Depending on the assigned Risk Level/Code (or Risk priority), take the corresponding action according to Table 12: • • •

If Risk priority is LOW (3) for a task step requires no further action. If Risk priority is MEDIUM (2) - select and implement appropriate controls. If Risk priority is HIGH (1) - immediately stop the task step until appropriate controls can be implemented.

A high risk priority means that there is a reasonable to high probability that an employee will be killed or permanently disabled doing this task step and/or a high probability that the employee will suffer severe illness or injury. Step 4. Select PPE: Try to reduce employee exposure to the hazard by first implementing engineering, work practice, and/or administrative controls. If PPE is assigned, it must be appropriately matched to the hazard to provide effective protection, durability, and proper fit to the worker. Note the control method to be implemented in the far right column. Guidance on selection of appropriate PPE is provided in Sec.2(g). Step 5. Certify the hazard assessment: • •

Certify on the completed hazard assessment form that the hazard assessment has been performed and that the needed controls have been implemented. Incorporate any new PPE requirements that have developed into a written accident prevention program.

Exhibit 2 is an example of a form that can be copied and used to certify the assessment.

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Part II: Safety and Best Industry Practices

Exhibit 2. Job Hazard Analysis for Personal Protective Equipment (PPE) Assessment Certification Form Job/Task: ______________________________ Location: ______________________________ Job/Task Step

Hazard Type

Hazard Source

Body Parts Severity Probability Risk At Risk Code

Control Method(1)

(1) Note: Engineering, work practice, and/or administrative hazard controls such as guarding must be used, if feasible, before requiring employees to use personal protective equipment. Certification of Assessment * Name of work place: ________________________________ * Address:__________________________________________ *Assessment Conducted By: _________________________ Title:________________________ *Date(s) of Assessment ________________ Implementation of Controls Approved By: ________________________ Title:______________________ Date:__________

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2(f)(3)(iii) General Provisions for Performing Safety Inspections Inspections. Inspections identify and eliminate unsafe acts or conditions before accidents or injuries occur. Two types of planned inspections are made: facility safety and health inspections and workplace and project inspections. Facility safety and health inspections are the focus of this subsection. Workplace and project inspections incorporate standards established in the Nigerian Electricity Health and Safety Standards Handbook. Responsibility. • The Health & Safety Officer (HSO) is responsible for facility safety and health inspections. • Unit manager shall ensure that workplace and project inspections are done by persons knowledgeable of the work activity and who have had training in the Nigerian Electricity Health and Safety Code Handbook standards, Occupational Safety, the inspection process, and use of inspection report forms. Frequency of Workplace and Project Inspections. All regularly used facilities shall be inspected at least annually. Workplace and project inspections shall be done at least annually. Inspect high-risk workplaces more frequently. High-Risk Workplaces. Any facility or operation that offers a high potential for injury, illness, or death due to the activity conducted at the location is a high-risk workplace. Examples are: •

• • • • • •

Storage areas of: – All types of flammables, including paint. – Explosives, chemicals, toxicants, or radioactive materials. – Materials stacked in such manner that they could overload structural systems or fall upon employees working in the area. Vehicle and equipment maintenance, carpentry, and other shops. Any location housing an activity involving powered machinery, equipment, electrical devices, and other mechanical apparatus. Loading operations or operations involving frequent backing or overhead handling of material; for example, ware-housing and zone fire caches. Operations involving chemical storage or usage. All facilities used for housing personnel. All energized points and high energy transmission systems.

Inspection Content. Compare actual situations and conditions to accepted standards. Variations of actual conditions from these standards are deficiencies. These may be classified as either unsafe conditions or unsafe acts. These may be imminently dangerous, serious, or nonserious. The Nigerian Electricity Health and Safety Code Handbook, serves as the basic source of standards for workplace and project inspections.

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Critical Inspection Items. Certain parts of equipment and some operations are critical to safe use or safe completion of a job. When a critical part fails or is absent, the machine, equipment, or operation will fail with a high likelihood of losses. Inspect for the presence and safe operation of these critical items. Some examples are: • • • •

Pop-off valve on hot water heater. Anti-flashback couplings on oxygen-acetylene torches. Proper storage of flammable liquids. Eyewash stations in chemical use areas.

Inspection Checklists. Several types of checklists and inspection forms are available from commercial sources. These can be customized to meet local conditions and improve the quality of inspections. Examples are included in this subsection and may be modified to fit the needs of the facility. Use of Inspection Forms. Safety and Health Inspection Forms, Compliance Worksheets, and Report Narratives are suggested for documenting the inspections. These are designed to assist in documenting notices of Unsafe or Unhealthful Working Conditions. Computerized or electronically reproduced forms containing similar information may also be used. 2(f)(3)(iv) Inspection Preparation Inspectors shall prepare for inspections as follows: 1. If the unit is covered by a bargaining agreement, arrange for a union representative to accompany you on the inspection. 2. Review previous inspection reports, reports of unsafe conditions, accident reports, and the unit's program of work to become familiar with the operations of the site to be inspected. 3. Arrange for the unit manager or designee to accompany you. 4. Prepare inspection equipment. 5. Review applicable safety and health standards. 6. Review inspection checklists and other material. 7. Review material to be covered in the opening conference. 2(f)(3)(v) Hazard Classification Hazards found during an inspection shall be classified so that managers can allocate time and dollars for their correction in order of priority based on the degree of danger present. Hazards shall be classified as: imminent danger, serious, and non-serious based on the following criteria. •

Imminent danger hazards would likely cause death, severe injury or high property losses immediately, or before the hazard can be eliminated through normal procedures. Immediate employee protection and abatement is required. An example is a leaking propane gas cylinder in crew quarters.

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Serious hazards are those in which there is high probability that serious injury, illness, or extensive property damage would result unless corrective action is taken. Abatement shall be accomplished within 14 days. An example is a broken stair tread. Non-serious hazards are those that could cause injury, illness, or property damage. Abatement shall be accomplished in 30 days. An example is a broken window in a workshop.

2(f)(3)(vi) Inspection Equipment Inspectors shall use test or sampling equipment when required to evaluate workplace conditions. Some basic types are listed below. Some situations and conditions require sophisticated equipment that may not be readily available. Contact the Regional Office or Station headquarters for assistance. Basic Sampling Equipment Type or Name Noise Meter Detector Tube Pump Smoke Tubes Velometer

Application To measure noise levels of equipment or processes. To measure levels of airborne contaminants with appropriate tubes To identify air flow currents. To measure air flow such as in laboratory hoods.

Basic Inspection Equipment Receptacle Tester Tape Measure Flashlight Clipboard Camera with Flash

Indicates if an electrical receptacle box of 110 voltage is correctly wired.

2(f)(3)(vii) Inspection Process The inspection process shall be a closed loop system to ensure correction of hazards. The following is a graphic display of a closed loop inspection program. 1. Conducting the Inspection 2. Opening Conference. Discuss the following: a. Purpose of the inspection. b. Items or areas of special interest. c. Involvement of employees or employee representatives. d. Inspection standards to be applied. e. Time and place for a closing conference. 3. Inspection Procedure. Inspection of a workplace or project must be planned to ensure that all situations and conditions are observed. 4. Plan the route of inspection within a workplace inspecting high hazard areas first. Develop an inspection pattern. Complete the inspection of each area before going on. A random pattern is not effective.

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5. Wear required protective equipment. 6. Look for imminent danger and serious hazards, then non-serious hazards. 7. Note unsafe acts of employees, or indicators of unsafe acts, and point these out to the manager's representative. 8. Look for good things as well as deficiencies. Note well-organized areas or unique ways of accomplishing work safely. 9. Look for safety and health program promotional items, such as an active poster program, current safety plans, current bulletin boards, and awards. 10. Search for patterns of deficiencies that affect the entire worksite. An example would be water in all the air compressors. This is a strong indicator that no compressor drain program exists. 11. Don't make assumptions. Ask questions, try it, turn it on, shake it, open it up, look at it. Take your time. Be systematic. 12. Remove equipment and tools that are deficient or suspected of being deficient from service. Use appropriate forms for Ground Equipment Warning Tag, to mark them. 13. Photograph conditions that would be difficult to describe or that rapidly change. 2(f)(3)(viii) Closeout Review At the conclusion of the inspection, meet with the unit manager or representative. Inform the person of unsafe or unhealthful working conditions found during the inspection. Include other topics such as: • • • • • •

Positive things found. The extent of deficiencies found, such as no air compressor drain program or no fire extinguisher inspection program. The list of red-tagged and removed-from-service tools and equipment. Noise readings on measured equipment. The unit manager's responsibilities to correct the hazards and the hazard classification ratings. Period of time for the abatement of the unsafe and unhealthful conditions.

2(f)(3)(ix) Abatement Plan If correction of the noted deficiency cannot be accomplished within 30 days of the inspection, the unit manager shall prepare an abatement plan and submit it to the next higher organizational level. 2(f)(4) Hazard Assessment and PPE Checklists This subsection contains checklists that will assist in assigning personal protective equipment, including, but is not limited to, safety glasses, goggles, hard hats, gloves, safety shoes, and heat or electrically resistant clothing. Electrical protective equipment, respiratory protection, hearing protection, PPE for construction site lasers, and equipment like safety belts, lifelines, lanyards, and safety nets, are addressed in separate checklists. It is important to note that engineering controls should be the primary method of establishing a safe workplace. Personal protective equipment should only be used where engineering controls are not feasible. II-191

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Checklist 1. General Safety Please Circle General Requirements Has a hazard assessment been conducted in the workplace to identify possible hazards that would require the use of PPE? Is there a written certification of hazard assessment which identifies the workplace evaluated, the person certifying that the evaluation has been performed, and the date(s) of the hazard assessment?

Y N N/A ??

Y N N/A ??

Based on the hazards identified, has PPE been selected for all appropriate individuals?

Y N N/A ??

Have individuals involved been informed of the PPE selection decisions?

Y N N/A ??

If PPE is necessary to prevent injury or impairment by exposure to chemical hazards, radiological hazards, or mechanical irritants through absorption, inhalation or physical contact, is it provided?

Y N N/A ??

Has the selected PPE been fitted to appropriate individuals?

Y N N/A ??

Is PPE maintained in a sanitary and reliable condition?

Y N N/A ??

Do appropriate individuals use the PPE selected?

Y N N/A ??

Is defective or damaged PPE removed from service immediately? (shall not be used)

Y N N/A ??

Training Has each individual who is required to use PPE been provided with training?

Y N N/A ??

Has training on PPE included all of the following elements: when PPE is necessary; what PPE is necessary; how to properly don, doff, adjust, and wear PPE; the limitations of the PPE; and the proper care, maintenance, useful life and disposal of the PPE.

Y N N/A ??

Have the trained individuals demonstrated an understanding of the training and the ability to use PPE properly before being allowed to perform work requiring the use of PPE?

Y N N/A ??

Are individuals retrained when there is reason to believe that they do not have the understanding or skill to use PPE properly?

Y N N/A ??

Is retraining conducted whenever changes in the workplace or changes in types of PPE make previous training obsolete?

Y N N/A ??

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Is there written certification for each person who has received PPE training that includes the following: a statement indicating the person understood the training; the name of the person trained; the date(s) of the training; and the subject of the certification?

Y N N/A ??

Head, Foot, and Hand Protection Are protective helmets used wherever there is the possible danger of head injury from impact, or from falling or flying objects, or from electrical shock and burns?

Y N N/A ??

Do protective helmets that are used in the workplace that were purchased prior to July 5, 1994 meet the American Nigerian Standard Safety Requirements for Industrial Head Protection, ANSI Z89.1-1969?

Y N N/A ??

Do protective helmets that are used in the workplace that were purchased after July 5, 1994 meet the American Nigerian Standard for Personnel Protection--Protective Headwear for Industrial Workers--Requirements, ANSI Z89.1-1986?

Y N N/A ??

Is protective footwear used wherever there is the danger of foot injuries due to falling or rolling objects, or objects piercing the sole, and where feet are exposed to electrical hazards?

Y N N/A ??

Does protective footwear that is used in the workplace that was purchased prior to July 5, 1994 meet the requirements of the American Nigerian Standard for Men's Safety-Toe Footwear, ANSI Z41.1-1967?

Y N N/A ??

Does protective footwear that is used in the workplace that was purchased after July 5, 1994 meet the requirements of the American Nigerian Standard for Personal Protection--Protective Footwear, ANSI Z41-1991?

Y N N/A ??

Are appropriate protective gloves used wherever there is the danger to hands of exposure to hazards such as those from skin absorption of harmful substances, severe cuts or lacerations, severe abrasions, punctures, chemical burns, thermal burns, and harmful temperature extremes?

Y N N/A ??

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Eye and Face Protection Are individuals issued and required to wear appropriate eye protective devices while participating or observing activities which present a potential eye safety hazard? Note: Eye potential hazards include: caustic or explosive chemicals or materials, hot liquids or solids, molten materials, welding operations of any type, repairing or servicing of vehicles, heat treatment or tempering of metals, the shaping of solid materials and laser device operation and experimentation.

Y N N/A ??

Do all protective eye and face devices purchased after July 5, 1994 comply with Z87.1-1989? Note: Regular prescription eye glasses do not meet this requirement. Goggles or other protective glasses meeting the American Nigerian Standard must be worn over-top prescription eye glasses.

Y N N/A ??

Posting Requirements Are all lab or shop entrances, areas and equipment requiring the use of PPE devices posted with a sign indicating this requirement?

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Checklist 2 Chemical Safety Checklist - The objective of this surveillance is to ensure that practices for handling, storing, and using chemicals provide effective protection for the health and safety of employees. Surveillance Guideline CHEMICAL SAFETY Surveillance No.:______________ Facility: _____________________ Date Completed:______________ Activity 1: Evaluate the general hazard communication program, including documentation and training, MSDS availability, worker exposure control, etc. Yes No N/A ___ ___ ___ 1. Is there a written hazard communication program which addresses labeling and other forms of warning, material data safety sheets (MSDS), and employee information and training? ___ ___ ___ 2. Is there a list of hazardous chemicals known to be present that also provides a reference to appropriate MSDSs? ___ ___ ___ 3. Is a hazard communication program available to all employees? ___ ___ ___ 4. Are MSDSs readily available during each work shift to employees in their workplace for each hazardous chemical? ___ ___ ___ 5. Do employees receive effective information and training on hazardous chemicals in their work area or with which they work? • • •

Does the training include the physical and health hazards of the chemicals including exposure limits? Does the training include measures employees can take to protect themselves from the chemical hazards (procedures, work practices, and PPE)? Does the training include the details of the hazard communication program, including an explanation of the labeling system, MSDSs, and how employees can obtain and use hazard information?

___ ___ ___ 6. Have the employees been informed of the location and availability of the written hazard communication program, the required list of chemicals, and the location of MSDSs?

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___ ___ ___ 7. Do employers ensure that employees do not exceed Permissible Exposure Levels (PEL) or American Conference of Governmental Industrial Hygienist Threshold Limit Values (TLV), whichever is more restrictive? ___ ___ ___ 8. Do employers measure employee exposure to chemicals if it is believed that action levels or PELs may have been exceeded? ___ ___ ___ 9. Do employers notify employees of monitoring results within 15 workdays of receipt of such information? ___ ___ ___ 10. Do employers have a Chemical Hygiene Plan for laboratory use of chemicals (laboratory use - laboratory scale, multiple chemicals/procedures, non-production chemical use, standard laboratory protective practices)? • • • • • • •

Is the Chemical Hygiene Plan capable of protecting employees from health hazards associated with hazardous chemicals? Does the Chemical Hygiene Plan provide provision for keeping exposures below limits? Is the Chemical Hygiene Plan readily available to employees? Does the Chemical Hygiene Plan identify standard operating procedures relevant to safety and health considerations for handling chemicals? Does the Chemical Hygiene Plan provide criteria used to determine and implement control measures to reduce employee exposure the hazardous chemicals? Does the Chemical Hygiene Plan provide requirements that fume hoods and other protective equipment function properly? Does the Chemical Hygiene Plan contain provisions for employee information and training relative to chemical hazards?

___ ___ ___ 13. Do training records substantiate that workers have received required training on hazard recognition and control related to chemical safety? Activity 2: Observe chemical storage locations and storage practices. Yes No N/A ___ ___ ___ 14. Is each container containing a hazardous chemical labeled, tagged or marked with the identity of the chemical, and appropriate hazard warnings? (Labels are not required on portable containers into which chemicals are transferred from labeled containers and which are intended only for the immediate use of the employee who made the transfer.) ___ ___ ___15. Are the labels on containers legible and prominently displayed? ___ ___ ___ 16. Do containers and portable tanks containing flammable and combustible liquids meet UN hazard warning requirements? ___ ___ ___ 17. Is each portable tank containing flammable/combustible liquid provided with a means of venting to limit internal pressure to less than 68.94 kPa?

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___ ___ ___ 18. Do flammable storage cabinets contain less than 227.1 liters of Class I or Class II liquids, or less than 454.1 liters of Class III liquids? ___ ___ ___ 19. Are flammable storage cabinets conspicuously labeled "Flammable Keep Fire Away"? ___ ___ ___ 20. Does the flammable storage cabinet meet the design requirements? ___ ___ ___ 21. Do flammable storage rooms meet the requirements of safe room design, quantity of liquid stored, ventilation, storage spacing requirements, electrical wiring, etc.? ___ ___ ___ 22. Are suitable fire control devices, such as fire extinguishers, available at locations where flammable or combustible liquids are stored? ___ ___ ___ 23. Are incompatible chemicals/materials segregated to prevent accidental contact with one another? ___ ___ ___ 24. Is the minimum amount of hazardous chemical necessary for work stored in the open in the laboratory work area? ___ ___ ___ 25. Are safety showers and/or an eyewash stations provided within the work area for immediate emergency use? Activity 3: Observe work activities involving handling or use of chemicals. Yes No N/A ___ ___ ___ 26. Are users of flammable/combustible liquids familiar with the hazard classification of the liquid? ___ ___ ___ 27. Is bonding used when transferring Class I flammable liquids between two conductive containers of greater volume than 4.2 liters? ___ ___ ___ 28. Has the maintenance work package or work activity been reviewed by representatives of the safety and/or environmental organizations for appropriate safety and environmental controls? ___ ___ ___ 29. Was an appropriate job safety analysis performed for the work activity, identifying the hazards and implementing controls? ___ ___ ___ 30. Do the work instructions address use of specific personnel protective equipment such as safety glasses with side shields, rubber gloves, aprons, etc.? ___ ___ ___ 31. Do the work instructions include procedures in sufficient detail to ensure the safety and health of the workers?

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___ ___ ___ 32. Were potential chemical hazards discussed with workers during the pre-job brief? ___ ___ ___ 33. Are workers using the personal protective equipment specified in the work instructions or procedures while performing the activity? ___ ___ ___ 34. Do workers follow instructions/procedures prescribed in the work package? ___ ___ ___ 35. Can workers describe the chemical hazards associated with the work they are performing? ___ ___ ___ 36. Were workers provided the opportunity to review and understand the MSDSs for chemicals associated with the activity? ___ ___ ___ 37. Can workers describe the correct response to an emergency involving chemical hazards? NOTE The Facility Representative should avoid interrupting maintenance personnel performing work on systems containing hazardous chemicals. The Facility Representative should wait for opportune times to conduct business with Facility Operators. OTHER: NOTES/COMMENTS: PERSONNEL CONTACTED: PROCEDURES REVIEWED: FINDINGS: Finding No.: Description: OBSERVATIONS: Observation No.: Description:

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FOLLOW-UP ITEMS: CONTRACTOR MANAGEMENT DEBRIEFED AND RESULTS:

Signature: ___________________________________ Date: _____/_____/_____ Facility Representative

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2(f)(5) Bibliography Cheremisinoff, N. P., 1996Safety Management Practices for Hazardous Materials, Marcel Dekker Publishers, N.Y. DOE 5480.4, Environmental Protection, Safety and Health Protection Standards DOE O 440.1A, Worker Protection Management for DOE Federal and Contractor Employees DOE G 440.1-1, Worker Protection Management for DOE Federal and Contractor Employees Guide DOE G 440.1-3, Occupational Exposure Assessment Implementing Guide DOE-HDBK-1100-96, Chemical Hazard Analysis DOE-HDBK-1101-96, Process Safety Management for Highly Hazardous Chemicals 29 CFR 1910.106, Flammable and Combustible Liquids 29 CFR 1910.119, Process Safety Management of Highly Hazardous Chemicals 29 CFR 1910.1200, Hazard Communication 29 CFR 1910.1450, Occupational Exposures to Hazardous Chemicals in Laboratories 29 CFR 1910.132, Personal Protective Equipment, General Requirements 48 CFR 970.5204-2, Integration of Environment, Safety, and Health Into Work Planning and Execution 10 CFR 830.120, Quality Assurance Nigerian Fire Protection Association, Standard 45, Fire Protection for Laboratories Using Chemicals American Conference of Governmental Industrial Hygienists, Threshold Limit Values for Chemical Substances and Physical Agents and Biological Exposure Indices

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SEC. 2(g) PERSONAL PROTECTIVE EQUIPMENT CONTENTS 2(g)(1) Introduction ..............................................................................................................II-203 2(g)(2) General Provisions....................................................................................................II-203 2(g)(3) Requirements of a PPE Program ............................................................................II-203 2(g)(4) Guidelines for PPE Selection ...................................................................................II-205 2(g)(5) Worker Training.......................................................................................................II-205 2(g)(6) Eye and Face Protection...........................................................................................II-206 2(g)(6)(i) Prescription Lenses .............................................................................................. II-206 2(g)(6)(ii) Eye Protection for Exposed Workers ................................................................. II-206 2(g)(6)(iii) Types of Protection............................................................................................ II-207 2(g)(6)(iv) Welding Operations ........................................................................................... II-207 2(g)(6)(v) Laser Operations ................................................................................................. II-208 2(g)(7) Head Protection ........................................................................................................II-208 2(g)(7)(i) Types of Hard Hats .............................................................................................. II-209 2(g)(7)(ii) Size and Care ...................................................................................................... II-209 2(g)(8) Foot and Leg Protection...........................................................................................II-209 2(g)(8)(i) Special Purpose Shoes ......................................................................................... II-209 2(g)(8)(ii) Protective Footwear Care ................................................................................... II-209 2(g)(9) Hand and Arm Protection .......................................................................................II-210 2(g)(9)(i) Protective Gloves Types ..................................................................................... II-210 2(g)(9)(ii) Fabric and Coated Fabric Gloves ....................................................................... II-210 2(g)(9)(iii) Chemical- and Liquid-Resistant Gloves............................................................ II-210 2(g)(9)(iv) Protective Gloves Care ...................................................................................... II-214 2(g)(10) Protective Equipment for the Body ......................................................................II-214 2(g)(11) Hearing Protection .................................................................................................II-214 2(g)(12) Respiratory Protection ...........................................................................................II-215 2(g)(12)(i) Definitions ......................................................................................................... II-215 2(g)(12)(ii) Establishing a Respiratory Protection Program................................................ II-218 2(g)(12)(iii) Levels of Protection......................................................................................... II-223 2(g)(12)(iv) Rules for Breathing Air Quality and Use......................................................... II-225 2(g)(13) Bibliography............................................................................................................II-227

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2(g)(1) Introduction The NERC requires the use of personal protective equipment (PPE) to reduce employee exposure to hazards when engineering and administrative controls are not feasible or effective in reducing these exposures to acceptable levels. Employers are required to determine if PPE should be used to protect their workers. If PPE is to be used, a PPE program should be implemented. This program should address the hazards present; the selection, maintenance, and use of PPE; the training of employees; and monitoring of the program to ensure its ongoing effectiveness. 2(g)(2) General Provisions Hazards exist in every workplace in many different forms: sharp edges, falling objects, flying sparks, chemicals, noise and a myriad of other potentially dangerous situations. The NERC requires that employers protect their employees from workplace hazards that can cause injury. Controlling a hazard at its source is the best way to protect employees. Depending on the hazard or workplace conditions, NERC recommends the use of engineering or work practice controls to manage or eliminate hazards to the greatest extent possible. For example, building a barrier between the hazard and the employees is an engineering control; changing the way in which employees perform their work is a work practice control. When engineering, work practice and administrative controls are not feasible or do not provide sufficient protection, employers are required to provide personal protective equipment (PPE) to their employees and ensure its use. PPE is equipment worn to minimize exposure to a variety of hazards. Examples of PPE include such items as gloves, foot and eye protection, protective hearing devices (earplugs, muffs) hard hats, respirators and full body suits. This subsection will help both employers and employees do the following: • • • •

Understand the types of PPE, Know the basics of conducting a "hazard assessment" of the workplace, Select appropriate PPE for a variety of circumstances, Understand what kind of training is needed in the proper use and care of PPE.

The information in this guide is general in nature and does not address all workplace hazards or PPE requirements. The information, methods and procedures in this subsection are based on a number of references noted in the Bibliography and may be considered general guidance. The employer should perform a job hazards assessment (see Sec. 2(f)) before deciding on the levels of protection required and in selecting specific PPE to match work environment conditions. 2(g)(3) Requirements of a PPE Program The objective of a PPE program is to ensure the greatest possible protection for employees in the workplace. Cooperative efforts of both employers and employees will help in establishing and maintaining a safe and healthful work environment.

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Employers are responsible for: • • • • •

Performing a "job hazard assessment" of the workplace to identify and control physical and health hazards. Identifying and providing appropriate PPE for employees. Training employees in the use and care of the PPE. Maintaining PPE, including replacing worn or damaged PPE. Periodically reviewing, updating and evaluating the effectiveness of the PPE program.

Employees should: • • • •

Properly wear PPE, Attend training sessions on PPE, Care for, clean and maintain PPE, and Inform a supervisor of the need to repair or replace PPE

A PPE Program should be designed based on comprehensive safety and health program which should be unto itself based on identification of physical and health hazards in the workplace. This process is known as a "hazard assessment" or a “job hazards assessment (Sec. 2(f)). Potential hazards may be physical or health-related and a comprehensive hazard assessment should identify hazards in both categories. Examples of physical hazards include moving objects, fluctuating temperatures, high intensity lighting, rolling or pinching objects, electrical connections and sharp edges. Examples of health hazards include overexposure to harmful dusts, chemicals or radiation. The hazard assessment should begin with a walk-through survey of the facility to develop a list of potential hazards in the following basic hazard categories: • • • • • • • •

Impact, Penetration, Compression (roll-over), Chemical, Heat/cold, Harmful dust, Light (optical) radiation, and Biologic.

In addition to noting the basic layout of the facility and reviewing any history of occupational illnesses or injuries, things to look for during the walk-through survey include: • • •

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Sources of electricity. Sources of motion such as machines or processes where movement may exist that could result in an impact between workers and equipment. Sources of high temperatures that could result in burns, eye injuries or fire.

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Types of chemicals used in the workplace. Sources of harmful dusts. Sources of light radiation, such as welding, brazing, cutting, furnaces, heat treating, high intensity lights, etc. The potential for falling or dropping objects. Sharp objects that could poke, cut, stab or puncture. Biologic hazards such as blood or other potentially infected material.

When the walk-through is complete, the employer should organize and analyze the data so that it may be efficiently used in determining the proper types of PPE required at the worksite. The employer should become aware of the different types of PPE available and the levels of protection offered. It is a good idea to select PPE that will provide a level of protection greater than the minimum required to protect employees from hazards. The workplace should be periodically reassessed for any changes in conditions, equipment or operating procedures that could affect occupational hazards. This periodic reassessment should also include a review of injury and illness records to spot any trends or areas of concern and taking appropriate corrective action. The suitability of existing PPE, including an evaluation of its condition and age, should be included in the reassessment. Documentation of the hazard assessment is required through a written certification that includes the following information: • • • •

Identification of the workplace evaluated; Name of the person conducting the assessment; Date of the assessment; and Identification of the document certifying completion of the hazard assessment.

Refer to Sec. 2(f) for further guidance and inspection forms that will aid in performing the job hazards assessment. 2(g)(4) Guidelines for PPE Selection All PPE clothing and equipment should be of safe design and construction, and should be maintained in a clean and reliable fashion. Employers should take the fit and comfort of PPE into consideration when selecting appropriate items for their workplace. 2(g)(5) Worker Training Employers are required to train each employee who must use PPE. Employees must be trained to know at least the following: • • • • •

When PPE is necessary. What PPE is necessary. How to properly put on, take off, adjust and wear the PPE. The limitations of the PPE. Proper care, maintenance, useful life and disposal of PPE. II-205

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Employers should make sure that each employee demonstrates an understanding of the PPE training as well as the ability to properly wear and use PPE before they are allowed to perform work requiring the use of the PPE. If an employer believes that a previously trained employee is not demonstrating the proper understanding and skill level in the use of PPE, that employee should receive retraining. Other situations that require additional or retraining of employees include the following circumstances: •

changes in the workplace or in the type of required PPE that make prior training obsolete.

The employer must document the training of each employee required to wear or use PPE by preparing a certification containing the name of each employee trained, the date of training and a clear identification of the subject of the certification. 2(g)(6) Eye and Face Protection Employees can be exposed to a large number of hazards that pose danger to their eyes and face. Many occupational eye injuries occur because workers are not wearing any eye protection while others result from wearing improper or poorly fitting eye protection. Employers must be sure that their employees wear appropriate eye and face protection and that the selected form of protection is appropriate to the work being performed and properly fits each worker exposed to the hazard. 2(g)(6)(i) Prescription Lenses Everyday use of prescription corrective lenses will not provide adequate protection against most occupational eye and face hazards, so employers must make sure that employees with corrective lenses either wear eye protection that incorporates the prescription into the design or wear additional eye protection over their prescription lenses. It is important to ensure that the protective eyewear does not disturb the proper positioning of the prescription lenses so that the employee’s vision will not be inhibited or limited. Employees who wear contact lenses must wear eye or face PPE when working in hazardous conditions. 2(g)(6)(ii) Eye Protection for Exposed Workers NERC suggests that eye protection be routinely considered for use by carpenters, electricians, machinists, mechanics, millwrights, plumbers and pipefitters, sheetmetal workers and tinsmiths, assemblers, sanders, grinding machine operators, sawyers, welders, laborers, chemical process operators and handlers, and timber cutting and logging workers. Workers in other job categories should decide whether there is a need for eye and face PPE through a hazard assessment. Examples of potential eye or face injuries include: • •

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Dust, dirt, metal or wood chips entering the eye from activities such as chipping, grinding, sawing, hammering, the use of power tools or even strong wind forces. Chemical splashes from corrosive substances, hot liquids, solvents or other hazardous solutions.

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Objects swinging into the eye or face, such as tree limbs, chains, tools or ropes. Radiant energy from welding, harmful rays from the use of lasers or other radiant light (as well as heat, glare, sparks, splash and flying particles).

2(g)(6)(iii) Types of Protection Selecting the most suitable eye and face protection for employees should take into consideration the following elements: • • • • •

Ability to protect against specific workplace hazards. Should fit properly and be reasonably comfortable to wear. Should provide unrestricted vision and movement. Should be durable and cleanable. Should allow unrestricted functioning of any other required PPE.

The eye and face protection selected for employee use must identify the manufacturer. Any new eye and face protective devices must comply with interNigerian product safety standards of performance such as ANSI Z87.1-1989 or be at least as effective s these standard requires. The reader should examine product literature closely to ensure that equipment states performance being equivalent or exceeding an interNigerian product performance standard. 2(g)(6)(iv) Welding Operations Table 13 shows the minimum protective shades for a variety of welding, cutting and brazing operations in general industry practice. Table 13. Filter Lenses for Protection Against Radiant Energy.13

Welding Operation Shielded metal-arc welding 1.6-, 2.4-, 3.2-, 4.0-mm diameter electrodes Gas-shielded arc welding (nonferrous) 1.6-, 2.4-, 3.2-, 4.0-mm diameter electrodes Gas-shielded arc welding (ferrous) 1.6-, 2.4-, 3.2-, 4.0-mm diameter electrodes Shielded metal-arc welding 4.8-, 5.6-, 6.4-mm diameter electrodes 7.9-, 9.5-mm diameter electrodes Atomic hydrogen welding Carbon-arc welding Soldering Torch brazing Light cutting, up to 25.4 mm Medium cutting, 25.4 to 152.4 mm Heavy cutting, more than 152.4 mm Gas welding (light), up to 3.2-mm Gas welding (medium), 3.2- to 12.7-mm Gas welding (heavy), more than 12.7-mm 13

Shade Number 10 11 12 12 14 10 – 14 14 2 3 or 4 3 or 4 4 or 5 5 or 6 4 or 5 5 or 6 6 or 8

Source: 29 CFR 1926.102(b)(1).

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2(g)(6)(v) Laser Operations Laser retinal burns can be painless, so it is essential that all personnel in or around laser operations wear appropriate eye protection. Table 14 below lists maximum power or energy densities and appropriate protection levels for optical densities 5 through 8. Table 14. Recommended Laser Safety Glass14

Intensity, CW maximum Attenuation power density (watts/cm2) 10-2 10-1 1.0 10.0

Optical Density Attenuation (O.D.) factor 5 6 7 8

105 106 107 108

2(g)(7) Head Protection Protecting employees from potential head injuries is a key element of any safety program. Employers must ensure that their employees wear head protection if any of the following apply: • • •

Objects might fall from above and strike them on the head; They might bump their heads against fixed objects, such as exposed pipes or beams; or There is a possibility of accidental head contact with electrical hazards.

Examples of occupations in which employees should be required to wear head protection include construction workers, carpenters, electricians, linemen, plumbers and pipefitters, timber and log cutters, welders, among many others. Whenever there is a danger of objects falling from above, such as working below others who are using tools or working under a conveyor belt, head protection must be worn. Hard hats must be worn with the bill forward to protect employees properly. Protective helmets or hard hats should do the following: • • • •

Resist penetration by objects. Absorb the shock of a blow. Be water-resistant and slow burning. Have clear instructions explaining proper adjustment and replacement of the suspension and headband.

Hard hats must have a hard outer shell and a shock-absorbing lining that incorporates a headband and straps that suspend the shell from 2.54 cm to 3.18 cm away from the head. This type of design provides shock absorption during an impact and ventilation during normal wear.

14

Source: 29 CFR 1926.102(b)(2).

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In the U.S, OSHA standards recommend that protective headgear must meet ANSI Standard Z89.1-1986 (Protective Headgear for Industrial Workers) or provide an equivalent level of protection. The reader should review product literature carefully to ensure that protective headgear meets ANSI or similar interNigerian product performance standards. 2(g)(7)(i) Types of Hard Hats Hard hats are divided into three industrial classes: • • •

Class A hard hats provide impact and penetration resistance along with limited voltage protection (up to 2,200 volts). Class B hard hats provide the highest level of protection against electrical hazards, with high-voltage shock and burn protection (up to 20,000 volts). They also provide protection from impact and penetration hazards by flying/falling objects. Class C hard hats provide lightweight comfort and impact protection but offer no protection from electrical hazards.

2(g)(7)(ii) Size and Care Never drill holes, paint or apply labels to protective headgear as this may reduce the integrity of the protection. Do not store headgear in direct sunlight, such as on the rear window shelf of a car, since sunlight and extreme heat can damage them. 2(g)(8) Foot and Leg Protection If an employee’s feet may be exposed to electrical hazards, non-conductive footwear should be worn. On the other hand, workplace exposure to static electricity may necessitate the use of conductive footwear. Examples of situations in which an employee should wear foot and/or leg protection include: • • • • •

When heavy objects such as barrels or tools might roll onto or fall on the employee’s feet; Working with sharp objects such as nails or spikes that could pierce the soles or uppers of ordinary shoes; Exposure to molten metal that might splash on feet or legs; Working on or around hot, wet or slippery surfaces; and Working when electrical hazards are present.

2(g)(8)(i) Special Purpose Shoes Workers exposed to electrical hazards must never wear conductive shoes. Special Note: Nonconductive footwear must not be used in explosive or hazardous locations. 2(g)(8)(ii) Protective Footwear Care Workers should follow the manufacturers’ recommendations for cleaning and maintenance of protective footwear. II-209

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2(g)(9) Hand and Arm Protection If a workplace hazard assessment reveals that employees face potential injury to hands and arms that cannot be eliminated through engineering and work practice controls, employers must ensure that employees wear appropriate protection. 2(g)(9)(i) Protective Gloves Types The variety of potential occupational hand injuries makes selecting the right pair of gloves challenging. It is mandatory that employees use gloves provided by the employer. 2(g)(9)(ii) Fabric and Coated Fabric Gloves Fabric and coated fabric gloves are made of cotton or other fabric to provide varying degrees of protection. Fabric gloves protect against dirt, slivers, chafing and abrasions. They do not provide sufficient protection for use with rough, sharp or heavy materials. Adding a plastic coating will strengthen some fabric gloves. Coated fabric gloves are normally made from cotton flannel with napping on one side. By coating the unnapped side with plastic, fabric gloves are transformed into general-purpose hand protection offering slip-resistant qualities. These gloves are used for tasks ranging from handling bricks and wire to chemical laboratory containers. When selecting gloves to protect against chemical exposure hazards, always check with the manufacturer or review the manufacturer’s product literature to determine the gloves’ effectiveness against specific workplace chemicals and conditions. 2(g)(9)(iii) Chemical- and Liquid-Resistant Gloves Chemical-resistant gloves are made with different kinds of rubber: natural, butyl, neoprene, nitrile and fluorocarbon (viton); or various kinds of plastic: polyvinyl chloride (PVC), polyvinyl alcohol and polyethylene. These materials can be blended or laminated for better performance. As a general rule, the thicker the glove material, the greater the chemical resistance but thick gloves may impair grip and dexterity, having a negative impact on safety. Examples of chemicalresistant gloves include: •

•

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Butyl gloves are made of a synthetic rubber and protect against a wide variety of chemicals, such as peroxide, rocket fuels, highly corrosive acids (nitric acid, sulfuric acid, hydrofluoric acid and red-fuming nitric acid), strong bases, alcohols, aldehydes, ketones, esters and nitrocompounds. Butyl gloves also resist oxidation, ozone corrosion and abrasion, and remain flexible at low temperatures. Butyl rubber does not perform well with aliphatic and aromatic hydrocarbons and halogenated solvents. Natural (latex) rubber gloves are comfortable to wear, which makes them a popular general-purpose glove. They feature outstanding tensile strength, elasticity and temperature resistance. In addition to resisting abrasions caused by grinding and polishing, these gloves protect workers’ hands from most water solutions of acids, alkalis, salts and ketones. Latex gloves have caused allergic reactions in some individuals

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and may not be appropriate for all employees. Hypoallergenic gloves, glove liners and powderless gloves are possible alternatives for workers who are allergic to latex gloves. Neoprene gloves are made of synthetic rubber and offer good pliability, finger dexterity, high density and tear resistance. They protect against hydraulic fluids, gasoline, alcohols, organic acids and alkalis. They generally have chemical and wear resistance properties superior to those made of natural rubber. Nitrile gloves are made of a copolymer and provide protection from chlorinated solvents such as trichloroethylene and perchloroethylene. Although intended for jobs requiring dexterity and sensitivity, nitrile gloves stand up to heavy use even after prolonged exposure to substances that cause other gloves to deteriorate. They offer protection when working with oils, greases, acids, caustics and alcohols but are generally not recommended for use with strong oxidizing agents, aromatic solvents, ketones and acetates.

The following (Table 15) is a materials selection chart which will guide the reader in the selection of gloves based on the chemicals required to be handled on the job.

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Table 15. Material Chemical Resistance Guide15 (Key: VG: Very Good; G: Good; F: Fair; P: Poor (not recommended). Chemicals marked with an asterisk (*) are for limited service only)

Chemical Neoprene Acetaldehyde* VG Acetic acid VG Acetone* G Ammonium VG hydroxide Amy acetate* F Aniline G Benzaldehyde* F Benzene* P Butyl acetate G Butyl alcohol VG Carbon disulfide F Carbon F tetrachloride* Castor oil F Chlorobenzene* F Chloroform* G Chloronaphthalene F Chromic acid (50%) F Citric acid (10%) VG Cyclohexanol G Dibutyl phthalate* G Diesel fuel G Diisobutyl ketone P Dimethylformamide F Dioctyl phthalate G Dioxane VG Epoxy resins, dry VG Ethyl acetate* G Ethyl alcohol VG Ethyl ether* VG Ethylene F dichloride* Ethylene glycol VG Formaldehyde VG Formic acid VG Freon 11 G Freon 12 G Freon 21 G 15

Latex/Rubber G VG VG VG

Butyl

Nitrile

VG VG VG VG

G VG P VG

P F F P F VG F P

F F G P F VG F P

P P G F P VG F G

P P P P P VG F P P F F P G VG F VG G P

F F P F F VG G G P G G F G VG G VG VG F

VG P F F F VG VG G VG P G VG G VG F VG G P

VG VG VG P P P

VG VG VG F F F

VG VG VG G G G

U.S. Government publication titled Personal Protective Equipment, U.S. Department of Labor, Occupational Safety and Health Administration, OSHA 3151-12R, 2003

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Chemical Freon 22 Furfural* Gasoline, leaded Glycerin Hexane Hydrazine (65%) Hydrochloric acid Hydrofluoric acid (48%) Hydrogen peroxide (30%) G Hydroquinone Isooctane Kerosene Ketones Lacquer thinners Lactic acid (85%) Lauric acid (36%) Lineolic acid Linseed oil Maleic acid Methyl alcohol Methylamine Methyl bromide Methyl chloride* Methyl ethyl ketone* Methyl isobutyl ketone* Methyl metharcrylate Monoethanolamine Morpholine Naphthalene Napthas, aliphatic Napthas, aromatic Nitric acid* Nitric acid, red and white fuming Nitromethane (95.5%)* Nitropropane (95.5%) Octyl alcohol

Part II: Safety and Best Industry Practices

Neoprene G G G VG F F VG VG

Latex/Rubber P G P VG P G G G

Butyl

Nitrile

F G F VG P G G G

G G VG VG G G G G

G

G

G

G

G F VG G G VG VG VG VG VG VG F G P G

G P F VG F VG F P P VG VG F F P G

G P F VG F VG VG F F VG VG G G P VG

F VG VG P P VG VG G VG VG VG G F P P

F

F

VG

P

G

G

VG

F

VG VG G VG G G P

G VG F F P F P

VG VG F F P F P

VG G G VG G F P

F

P

F

F

F

P

F

F

VG

VG

VG

VG

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Chemical Oleic acid Oxalic acid Palmitic acid Perchloric acid (60%) Perchloroethylene Petroleum distillates (naphtha) Phenol Phosphoric acid Potassium hydroxide Propyl acetate Propyl alcohol Propyl alcohol (iso) Sodium hydroxide Styrene Styrene (100%) Sulfuric acid Tannic acid (65) Tetrahydrofuran Toluene* Toluene diisocyanate (TDI) Trichloroethylene* Triethanolamine (85%) Tung oil Turpentine Xylene*

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Neoprene VG VG VG VG

Latex/Rubber F VG VG F

Butyl

Nitrile

G VG VG G

VG VG VG G

F G

P P

P P

G VG

VG VG VG

F G VG

G VG VG

F VG VG

G VG VG VG P P G VG P F F

F VG VG VG P P G VG F P G

G VG VG VG P P G VG F P G

F VG VG VG F F G VG F F F

F VG

F G

P G

G VG

VG G P

P F P

F F P

VG VG F

2(g)(9)(iv) Protective Gloves Care Protective gloves should be inspected before each use to ensure that they are not torn, punctured or made ineffective in any way. 2(g)(10) Protective Equipment for the Body Workers who face possible bodily injury of any kind that cannot be eliminated through engineering, work practice or administrative controls, must wear appropriate body protection while performing their jobs. 2(g)(11) Hearing Protection Employee exposure to excessive noise depends upon a number of factors, including:

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The loudness of the noise as measured in decibels (dB). The duration of each employee’s exposure to the noise. Whether employees move between work areas with different noise levels. Whether noise is generated from one or multiple sources.

Generally, the louder the noise, the shorter the exposure time before hearing protection is required. For instance, employees may be exposed to a noise level of 85 dB for 8 hours per day (unless they experience a Standard Threshold Shift) before hearing protection is required. On the other hand, if the noise level reaches 115 dB hearing protection is required if the anticipated exposure exceeds 15 minutes. For a more detailed discussion of the requirements for a comprehensive hearing conservation program see Sec2(b). If engineering and work practice controls do not lower employee exposure to workplace noise to acceptable levels, employees must wear appropriate hearing protection. Manufacturers of hearing protection devices must display the device’s NRR on the product packaging. Some types of hearing protection include: • • •

Single-use earplugs are made of waxed cotton, foam, silicone rubber or fiberglass wool. They are self-forming and, when properly inserted, they work as well as most molded earplugs. Pre-formed or molded earplugs must be individually fitted by a professional and can be disposable or reusable. Reusable plugs should be cleaned after each use. Earmuffs require a perfect seal around the ear. Glasses, facial hair, long hair or facial movements such as chewing may reduce the protective value of earmuffs.

2(g)(12) Respiratory Protection In the control of those occupational diseases caused by breathing air contaminated with harmful dusts, fogs, fumes, mists, gases, smokes, sprays, or vapors, the primary objective of a respiratory protection program is to prevent atmospheric contamination. This should be accomplished as far as feasible by accepted engineering control measures (for example, enclosure or confinement of the operation, general and local ventilation, and substitution of less toxic materials). When effective engineering controls are not feasible, or while they are being instituted, appropriate respirators should be used. 2(g)(12)(i) Definitions The following U.S. OSHA definitions are important terms used in the respiratory protection standard in this subsection. Air-purifying respirator means a respirator with an air-purifying filter, cartridge, or canister that removes specific air contaminants by passing ambient air through the air-purifying element.

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Assigned protection factor (APF) means the workplace level of respiratory protection that a respirator or class of respirators is expected to provide to employees when the employer implements a continuing, effective respiratory protection program as specified by this section. Atmosphere-supplying respirator means a respirator that supplies the respirator user with breathing air from a source independent of the ambient atmosphere, and includes supplied-air respirators (SARs) and self-contained breathing apparatus (SCBA) units. Canister or cartridge means a container with a filter, sorbent, or catalyst, or combination of these items, which removes specific contaminants from the air passed through the container. Demand respirator means an atmosphere-supplying respirator that admits breathing air to the facepiece only when a negative pressure is created inside the facepiece by inhalation. Emergency situation means any occurrence such as, but not limited to, equipment failure, rupture of containers, or failure of control equipment that may or does result in an uncontrolled significant release of an airborne contaminant. Employee exposure means exposure to a concentration of an airborne contaminant that would occur if the employee were not using respiratory protection. End-of-service-life indicator (ESLI) means a system that warns the respirator user of the approach of the end of adequate respiratory protection, for example, that the sorbent is approaching saturation or is no longer effective. Escape-only respirator means a respirator intended to be used only for emergency exit. Filter or air purifying element means a component used in respirators to remove solid or liquid aerosols from the inspired air. Filtering facepiece (dust mask) means a negative pressure particulate respirator with a filter as an integral part of the facepiece or with the entire facepiece composed of the filtering medium. Fit factor means a quantitative estimate of the fit of a particular respirator to a specific individual, and typically estimates the ratio of the concentration of a substance in ambient air to its concentration inside the respirator when worn. Fit test means the use of a protocol to qualitatively or quantitatively evaluate the fit of a respirator on an individual. (See also Qualitative fit test QLFT and Quantitative fit test QNFT.) Helmet means a rigid respiratory inlet covering that also provides head protection against impact and penetration. High efficiency particulate air (HEPA) filter means a filter that is at least 99.97% efficient in removing monodisperse particles of 0.3 micrometers in diameter.

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Hood means a respiratory inlet covering that completely covers the head and neck and may also cover portions of the shoulders and torso. Immediately dangerous to life or health (IDLH) means an atmosphere that poses an immediate threat to life, would cause irreversible adverse health effects, or would impair an individual's ability to escape from a dangerous atmosphere. Interior structural firefighting means the physical activity of fire suppression, rescue or both, inside of buildings or enclosed structures which are involved in a fire situation beyond the incipient stage. (See 29 CFR 1910.155) Loose-fitting facepiece means a respiratory inlet covering that is designed to form a partial seal with the face. Maximum use concentration (MUC) means the maximum atmospheric concentration of a hazardous substance from which an employee can be expected to be protected when wearing a respirator, and is determined by the assigned protection factor of the respirator or class of respirators and the exposure limit of the hazardous substance. The MUC can be determined mathematically by multiplying the assigned protection factor specified for a respirator by the required permissible exposure limit, short-term exposure limit, or ceiling limit. When no exposure limit is available for a hazardous substance, an employer must determine an MUC on the basis of relevant available information and informed professional judgment. Negative pressure respirator (tight fitting) means a respirator in which the air pressure inside the facepiece is negative during inhalation with respect to the ambient air pressure outside the respirator. Oxygen deficient atmosphere means an atmosphere with an oxygen content below 19.5% by volume. Positive pressure respirator means a respirator in which the pressure inside the respiratory inlet covering exceeds the ambient air pressure outside the respirator. Powered air-purifying respirator (PAPR) means an air-purifying respirator that uses a blower to force the ambient air through air-purifying elements to the inlet covering. Pressure demand respirator means a positive pressure atmosphere-supplying respirator that admits breathing air to the facepiece when the positive pressure is reduced inside the facepiece by inhalation. Qualitative fit test (QLFT) means a pass/fail fit test to assess the adequacy of respirator fit that relies on the individual's response to the test agent. Quantitative fit test (QNFT) means an assessment of the adequacy of respirator fit by numerically measuring the amount of leakage into the respirator.

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Respiratory inlet covering means that portion of a respirator that forms the protective barrier between the user's respiratory tract and an air-purifying device or breathing air source, or both. It may be a facepiece, helmet, hood, suit, or a mouthpiece respirator with nose clamp. Self-contained breathing apparatus (SCBA) means an atmosphere-supplying respirator for which the breathing air source is designed to be carried by the user. Service life means the period of time that a respirator, filter or sorbent, or other respiratory equipment provides adequate protection to the wearer. Supplied-air respirator (SAR) or airline respirator means an atmosphere-supplying respirator for which the source of breathing air is not designed to be carried by the user. Tight-fitting facepiece means a respiratory inlet covering that forms a complete seal with the face. User seal check means an action conducted by the respirator user to determine if the respirator is properly seated to the face. 2(g)(12)(ii) Establishing a Respiratory Protection Program NERC requires the employer to develop and implement a written respiratory protection program with required worksite-specific procedures and elements for required respirator use. The program must be administered by a suitably trained program administrator. In any workplace where respirators are necessary to protect the health of the employee or whenever respirators are required by the employer, the employer shall establish and implement a written respiratory protection program with worksite-specific procedures. The program must be updated as necessary to reflect those changes in workplace conditions that affect respirator use. The employer shall include in the program the following provisions of this section, as applicable: • • • • • • • • •

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Procedures for selecting respirators for use in the workplace; Medical evaluations of employees required to use respirators; Fit testing procedures for tight-fitting respirators; Procedures for proper use of respirators in routine and reasonably foreseeable emergency situations; Procedures and schedules for cleaning, disinfecting, storing, inspecting, repairing, discarding, and otherwise maintaining respirators; Procedures to ensure adequate air quality, quantity, and flow of breathing air for atmosphere-supplying respirators; Training of employees in the respiratory hazards to which they are potentially exposed during routine and emergency situations; Training of employees in the proper use of respirators, including putting on and removing them, any limitations on their use, and their maintenance; and Procedures for regularly evaluating the effectiveness of the program.

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Where respirator use is not required an employer may provide respirators at the request of employees or permit employees to use their own respirators, if the employer determines that such respirator use will not in itself create a hazard. In addition, the employer must establish and implement those elements of a written respiratory protection program necessary to ensure that any employee using a respirator voluntarily is medically able to use that respirator, and that the respirator is cleaned, stored, and maintained so that its use does not present a health hazard to the user. Exception: Employers are not required to include in a written respiratory protection program those employees whose only use of respirators involves the voluntary use of filtering facepieces (dust masks). The employer shall designate a program administrator who is qualified by appropriate training or experience that is commensurate with the complexity of the program to administer or oversee the respiratory protection program and conduct the required evaluations of program effectiveness. The employer shall provide respirators, training, and medical evaluations at no cost to the employee. The employer must evaluate respiratory hazard(s) in the workplace, identify relevant workplace and user factors, and base respirator selection on these factors. This includes specifying appropriately protective respirators for use in IDLH atmospheres, and limits the selection and use of air-purifying respirators. The employer shall identify and evaluate the respiratory hazard(s) in the workplace; this evaluation shall include a reasonable estimate of employee exposures to respiratory hazard(s) and an identification of the contaminant's chemical state and physical form. Where the employer cannot identify or reasonably estimate the employee exposure, the employer shall consider the atmosphere to be IDLH. The employer shall select respirators from a sufficient number of respirator models and sizes so that the respirator is acceptable to, and correctly fits, the user. The employer must select a respirator for employee use that maintains the employee's exposure to the hazardous substance, when measured outside the respirator, at or below the MUC. Employers must not apply MUCs to conditions that are immediately dangerous to life or health (IDLH); instead, they must use respirators listed for IDLH conditions in paragraph (d)(2) of this standard. When the calculated MUC exceeds the IDLH level for a hazardous substance, or the performance limits of the cartridge or canister, then employers must set the maximum MUC at that lower limit. The respirator selected shall be appropriate for the chemical state and physical form of the contaminant.

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Medical evaluation. Using a respirator may place a physiological burden on employees that varies with the type of respirator worn, the job and workplace conditions in which the respirator is used, and the medical status of the employee. Accordingly, this paragraph specifies the minimum requirements for medical evaluation that employers must implement to determine the employee's ability to use a respirator. The employer shall provide a medical evaluation to determine the employee's ability to use a respirator, before the employee is fit tested or required to use the respirator in the workplace. The employer may discontinue an employee's medical evaluations when the employee is no longer required to use a respirator. The medical evaluation shall obtain the information requested by the questionnaire. The employer shall ensure that a follow-up medical examination is provided for an employee who gives a positive response to any question. The follow-up medical examination shall include any medical tests, consultations, or diagnostic procedures that the examiner deems necessary to make a final determination. The employer shall provide the employee with an opportunity to discuss the questionnaire and examination results with the medical examiner. Fit testing. This is an important part of a program. It requires that, before an employee may be required to use any respirator with a negative or positive pressure tight-fitting facepiece, the employee must be fit tested with the same make, model, style, and size of respirator that will be used. The employer shall ensure that employees using a tight-fitting facepiece respirator pass an appropriate qualitative fit test (QLFT) or quantitative fit test (QNFT). Continuing respirator effectiveness. Appropriate surveillance shall be maintained of work area conditions and degree of employee exposure or stress. When there is a change in work area conditions or degree of employee exposure or stress that may affect respirator effectiveness, the employer shall reevaluate the continued effectiveness of the respirator. The employer shall ensure that employees leave the respirator use area: • • •

To wash their faces and respirator facepieces as necessary to prevent eye or skin irritation associated with respirator use; or If they detect vapor or gas breakthrough, changes in breathing resistance, or leakage of the facepiece; or To replace the respirator or the filter, cartridge, or canister elements.

If the employee detects vapor or gas breakthrough, changes in breathing resistance, or leakage of the facepiece, the employer must replace or repair the respirator before allowing the employee to return to the work area. Maintenance and care of respirators. The recommended respiratory protection program requires the employer to provide for the cleaning and disinfecting, storage, inspection, and repair of respirators used by employees.

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Cleaning and disinfecting. The employer shall provide each respirator user with a respirator that is clean, sanitary, and in good working order. The respirators shall be cleaned and disinfected at the following intervals: a. Respirators issued for the exclusive use of an employee shall be cleaned and disinfected as often as necessary to be maintained in a sanitary condition; b. Respirators issued to more than one employee shall be cleaned and disinfected before being worn by different individuals; c. Respirators maintained for emergency use shall be cleaned and disinfected after each use; and d. Respirators used in fit testing and training shall be cleaned and disinfected after each use. Storage. The employer shall ensure that respirators are stored as follows: e. All respirators shall be stored to protect them from damage, contamination, dust, sunlight, extreme temperatures, excessive moisture, and damaging chemicals, and they shall be packed or stored to prevent deformation of the facepiece and exhalation valve. f. In addition emergency respirators shall be: i. Kept accessible to the work area; ii. Stored in compartments or in covers that are clearly marked as containing emergency respirators; and iii. Stored in accordance with any applicable manufacturer instructions. Inspection. The employer shall ensure that respirators are inspected as follows: g. All respirators used in routine situations shall be inspected before each use and during cleaning; h. All respirators maintained for use in emergency situations shall be inspected at least monthly and in accordance with the manufacturer's recommendations, and shall be checked for proper function before and after each use; and i. Emergency escape-only respirators shall be inspected before being carried into the workplace for use. j. The employer shall ensure that respirator inspections include the following: i. A check of respirator function, tightness of connections, and the condition of the various parts including, but not limited to, the facepiece, head straps, valves, connecting tube, and cartridges, canisters or filters; and ii. A check of elastomeric parts for pliability and signs of deterioration. iii. Section, self-contained breathing apparatus shall be inspected monthly. Air and oxygen cylinders shall be maintained in a fully charged state and shall be recharged when the pressure falls to 90% of the manufacturer's recommended pressure level. The employer shall determine that the regulator and warning devices function properly. iv. For respirators maintained for emergency use, the employer shall: (1) Certify the respirator by documenting the date the inspection was performed, the name (or signature) of the person who made the inspection, the findings, required remedial action, and a serial number or other means of identifying the inspected respirator; and (2) Provide this information on a tag or label that is attached to the storage compartment for the respirator, is kept with the respirator, or is included in

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inspection reports stored as paper or electronic files. This information shall be maintained until replaced following a subsequent certification. Repairs. The employer shall ensure that respirators that fail an inspection or are otherwise found to be defective are removed from service, and are discarded or repaired or adjusted in accordance with the following procedures: k. Repairs or adjustments to respirators are to be made only by persons appropriately trained to perform such operations and shall use only the respirator manufacturer's approved parts designed for the respirator; l. Repairs shall be made according to the manufacturer's recommendations and specifications for the type and extent of repairs to be performed; and m. Reducing and admission valves, regulators, and alarms shall be adjusted or repaired only by the manufacturer or a technician trained by the manufacturer.

Identification of filters, cartridges, and canisters. The employer shall ensure that all filters, cartridges and canisters used in the workplace are labeled and color coded with the NIOSH approval label and that the label is not removed and remains legible. Training and Recordkeeping. The employer shall provide effective training to employees who are required to use respirators. The training must be comprehensive, understandable, and recur annually, and more often if necessary. The employer shall ensure that each employee can demonstrate knowledge of at least the following: • • • • • • •

Why the respirator is necessary and how improper fit, usage, or maintenance can compromise the protective effect of the respirator; What the limitations and capabilities of the respirator are; How to use the respirator effectively in emergency situations, including situations in which the respirator malfunctions; How to inspect, put on and remove, use, and check the seals of the respirator; What the procedures are for maintenance and storage of the respirator; How to recognize medical signs and symptoms that may limit or prevent the effective use of respirators; and The general requirements of this section.

Training shall be conducted in a manner that is understandable to the employee. The employer shall provide the training prior to requiring the employee to use a respirator in the workplace. Retraining shall be administered annually, and when the following situations occur: • • •

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Changes in the workplace or the type of respirator render previous training obsolete; Inadequacies in the employee's knowledge or use of the respirator indicate that the employee has not retained the requisite understanding or skill; or Any other situation arises in which retraining appears necessary to ensure safe respirator use.

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Program evaluation and documentation. The employer is required to conduct evaluations of the workplace to ensure that the written respiratory protection program is being properly implemented, and to consult employees to ensure that they are using the respirators properly. The employer shall conduct evaluations of the workplace as necessary to ensure that the provisions of the current written program are being effectively implemented and that it continues to be effective. The employer shall regularly consult employees required to use respirators to assess the employees' views on program effectiveness and to identify any problems. Any problems that are identified during this assessment shall be corrected. Factors to be assessed include, but are not limited to: • • • •

Respirator fit (including the ability to use the respirator without interfering with effective workplace performance); Appropriate respirator selection for the hazards to which the employee is exposed; Proper respirator use under the workplace conditions the employee encounters; and Proper respirator maintenance.

Recordkeeping. This section requires the employer to establish and retain written information regarding medical evaluations, fit testing, and the respirator program. This information will facilitate employee involvement in the respirator program, assist the employer in auditing the adequacy of the program, and provide a record for compliance determinations by the NERC. 2(g)(12)(iii) Levels of Protection Respirators for IDLH atmospheres - The employer shall provide the following respirators for employee use in IDLH atmospheres: • •

A full facepiece pressure demand SCBA certified by NIOSH for a minimum service life of thirty minutes, or A combination full facepiece pressure demand supplied-air respirator (SAR) with auxiliary self-contained air supply.

For all IDLH atmospheres, the employer shall ensure that: • • • • •

One employee or, when needed, more than one employee is located outside the IDLH atmosphere; Visual, voice, or signal line communication is maintained between the employee(s) in the IDLH atmosphere and the employee(s) located outside the IDLH atmosphere; The employee(s) located outside the IDLH atmosphere are trained and equipped to provide effective emergency rescue; The employer or designee is notified before the employee(s) located outside the IDLH atmosphere enter the IDLH atmosphere to provide emergency rescue; The employer or designee authorized to do so by the employer, once notified, provides necessary assistance appropriate to the situation;

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Employee(s) located outside the IDLH atmospheres are equipped with: Pressure demand or other positive pressure SCBAs, or a pressure demand or other positive pressure supplied-air respirator with auxiliary SCBA; and either appropriate retrieval equipment for removing the employee(s) who enter(s) these hazardous atmospheres where retrieval equipment would contribute to the rescue of the employee(s) and would not increase the overall risk resulting from entry; or equivalent means for rescue where retrieval equipment is not required.

Procedures for interior structural firefighting. This is a special IDLH situation. The U.S. OSHA protocol requires: • • •

At least two employees enter the IDLH atmosphere and remain in visual or voice contact with one another at all times; At least two employees are located outside the IDLH atmosphere; and All employees engaged in interior structural firefighting use SCBAs.

One of the two individuals located outside the IDLH atmosphere may be assigned to an additional role, such as incident commander in charge of the emergency or safety officer, so long as this individual is able to perform assistance or rescue activities without jeopardizing the safety or health of any firefighter working at the incident. Nothing in this section is meant to preclude firefighters from performing emergency rescue activities before an entire team has assembled. All oxygen-deficient atmospheres shall be considered IDLH. Respirators for atmospheres that are not IDLH - The employer shall provide a respirator that is adequate to protect the health of the employee and ensure compliance with all other OSHA statutory and regulatory requirements, under routine and reasonably foreseeable emergency situations. For protection against gases and vapors, the employer shall provide: • •

An atmosphere-supplying respirator, or An air-purifying respirator, provided that the respirator is equipped with an end-ofservice-life indicator (ESLI) certified by NIOSH for the contaminant; or

For protection against particulates, the employer shall provide: • • •

An atmosphere-supplying respirator; or An air-purifying respirator equipped with a filter such as a high efficiency particulate air (HEPA) filter, or an air-purifying respirator equipped with a filter; or For contaminants consisting primarily of particles with mass median aerodynamic diameters (MMAD) of at least 2 micrometers, an air-purifying respirator equipped with any filter certified for particulates.

Assigned Protection Factors (APFs) - Employers must use the assigned protection factors listed in Table 16 below to select a respirator that meets or exceeds the required level of II-224

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employee protection. When using a combination respirator (e.g., airline respirators with an airpurifying filter), employers must ensure that the assigned protection factor is appropriate to the mode of operation in which the respirator is being used. Table 16. Assigned Protection Factors

Type of respirator1, 2

1. Air-Purifying Respirator 2. Powered Air-Purifying Respirator (PAPR) 3. Supplied-Air Respirator (SAR) or Airline Respirator • Demand mode • Continuous flow mode • Pressure-demand or other positive-pressure mode 4. Self-Contained Breathing Apparatus (SCBA) • Demand mode • Pressure-demand or other positive-pressure mode (e.g., open/closed circuit)

Quarter mask

Half mask

5 ..............

.............. .............. ..............

3

10 50

Loosefitting facepiece 50 .............. .............. 1,000 425/1,000 25

10 50 50

50 .............. .............. 1,000 425/1,000 25 1,000 .............. ..............

.............. 10 .............. ..............

Full Helmet/ facepiece hood

50 10,000

50 .............. 10,000 ..............

Notes: 1Employers may select respirators assigned for use in higher workplace concentrations of a hazardous substance for use at lower concentrations of that substance, or when required respirator use is independent of concentration. 2The assigned protection factors in Table are only effective when the employer implements a continuing, effective respirator program including training, fit testing, maintenance, and use requirements. 3This APF category includes filtering facepieces and half masks with elastomeric facepieces. 4The employer must have evidence provided by the respirator manufacturer that testing of these respirators demonstrates performance at a level of protection of 1,000 or greater to receive an APF of 1,000. This level of performance can best be demonstrated by performing a WPF or SWPF study or equivalent testing. Absent such testing, all other PAPRs and SARs with helmets/hoods are to be treated as loose-fitting facepiece respirators, and receive an APF of 25. 5These APFs do not apply to respirators used solely for escape. For escape respirators used in association with specific substances employers must refer to the appropriate substance-specific standards in that subpart.

2(g)(12)(iv) Rules for Breathing Air Quality and Use This subsection requires the employer to provide employees using atmosphere-supplying respirators (supplied-air and SCBA) with breathing gases of high purity. The employer shall ensure that compressed air, compressed oxygen, liquid air, and liquid oxygen used for respiration accords with the following specifications: •

Compressed and liquid oxygen shall meet the interNigerian requirements for medical or breathing oxygen; and

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Compressed breathing air shall meet at least the requirements for Grade D breathing air described in ANSI/Compressed Gas Association Commodity Specification for Air, G7.1-1989, to include: a. Oxygen content (v/v) of 19.5-23.5%; b. Hydrocarbon (condensed) content of 5 milligrams per cubic meter of air or less; c. Carbon monoxide (CO) content of 10 ppm or less; d. Carbon dioxide content of 1,000 ppm or less; and e. Lack of noticeable odor.

The employer shall ensure that compressed oxygen is not used in atmosphere-supplying respirators that have previously used compressed air. The employer shall ensure that oxygen concentrations greater than 23.5% are used only in equipment designed for oxygen service or distribution. The employer shall ensure that cylinders used to supply breathing air to respirators meet the following requirements: • • •

Cylinders are tested and maintained as prescribed in the Shipping Container Specification Regulations of the Department of Transportation (49 CFR part 173 and part 178) or equivalent Nigerian standard or equivalent EU standard; Cylinders of purchased breathing air have a certificate of analysis from the supplier that the breathing air meets the requirements for Grade D breathing air; and The moisture content in the cylinder does not exceed a dew point of -45.6 deg.C at 1 atmosphere pressure.

The employer shall ensure that compressors used to supply breathing air to respirators are constructed and situated so as to: • • • •

Prevent entry of contaminated air into the air-supply system; Minimize moisture content so that the dew point at 1 atmosphere pressure is 5.56 deg.C below the ambient temperature; Have suitable in-line air-purifying sorbent beds and filters to further ensure breathing air quality. Sorbent beds and filters shall be maintained and replaced or refurbished periodically following the manufacturer's instructions. Have a tag containing the most recent change date and the signature of the person authorized by the employer to perform the change. The tag shall be maintained at the compressor.

For compressors that are not oil-lubricated, the employer shall ensure that carbon monoxide levels in the breathing air do not exceed 10 ppm. For oil-lubricated compressors, the employer shall use a high-temperature or carbon monoxide alarm, or both, to monitor carbon monoxide levels. If only high-temperature alarms are used, the air supply shall be monitored at intervals sufficient to prevent carbon monoxide in the breathing air from exceeding 10 ppm. II-226

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The employer shall ensure that breathing air couplings are incompatible with outlets for nonrespirable worksite air or other gas systems. No asphyxiating substance shall be introduced into breathing air lines. 2(g)(13) Bibliography Eye and Face Protection: ANSI Z87.1-1989 (USA Standard for Occupational and Educational Eye and Face Protection). ANSI Standard Z89.1-1986 (Protective Headgear for Industrial Workers) Foot Protection: ANSI Z41.1-1991. A.M. Best Co. (AMB). 1990. Bests Safety Directory. AMB: Odwick, NJ. Hering, S.V., Ed. 1989. Air Sampling Instruments for Evaluation of Atmospheric Contaminants, American Conference of Governmental Industrial Hygienists: Cincinnati, Ohio. Handbook of Industrial Toxicology and Hazardous Materials, Cheremisinoff, N. P. , Marcel Dekker Publishers, NY, NY. , 1999 Chemical Protective Clothing Performance Index, 2nd Edition, Krister Forsberg, Lawrence H. Keith, ISBN: 978-0-471-32844-5, September 1999 Industrial Solvents Handbook, 2nd Edition, N. P. Cheremisinoff, Marcel Dekker Publishers, New York and Basel, 2003. Handbook of Hazardous Chemical Properties, N. P. Cheremisinoff, Butterworth-Heinemann, Oxford, UK 2000. Handbook of Pollution and Hazardous Materials Compliance, N. P. Cheremisinoff, Noyes Publications, Park Ridge, N.J., 1996. Noise Control in Industry, N. P. Cheremisinoff, Noyes Publications, Park Ridge, N.J., 1996. Materials Selection Deskbook, N. P. Cheremisinoff, Noyes Publications, Park Ridge, N.J., 1996. Safety Management Practices for Hazardous Materials, N. P. Cheremisinoff, Marcel Dekker Publishers, N.Y., 1996. Handbook of Emergency Response to Toxic Chemical Releases: A Guide to Compliance, N. P. Cheremisinoff, Noyes Publications, Park Ridge, N.J., 1995. Environmental and Health & Safety Management: A Guide to Compliance, N. P. Cheremisinoff, Noyes Publications, Park Ridge, N.J., 1995. Dangerous and Toxic Properties of Industrial and Consumer Products, N. P. Cheremisinoff, et. al., Marcel Dekker Publishers, Inc., N.Y., 1994.

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The following are links to WWW sites on safety equipment: http://www.occupationalhazards.com/zone/342/OHRespiratory_Protection.aspx http://www.osha.gov/SLTC/etools/respiratory/ http://www.cdc.gov/niosh/npptl/topics/protclothing/ http://www.osha.gov/dts/osta/otm/otm_viii/otm_viii_1.html

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SEC. 2(h) FIRST AID AND RESUSCITATION CONTENTS 2(h)(1) Introduction ..............................................................................................................II-231 2(h)(2) First Aid Assessments ..............................................................................................II-231 2(h)(3) Elements of a First Aid Training Program ............................................................II-232 2(h)(4) Periodic Program Updates ......................................................................................II-235 2(h)(5) First Aiders ...............................................................................................................II-235 2(h)(6) First Aid Training and Certification ......................................................................II-235 2(h)(7) First Aid for Electric Shock.....................................................................................II-236 2(h)(8) Skills Update .............................................................................................................II-237 2(h)(9) First Aid Supplies .....................................................................................................II-237 2(h)(10) Bibliography ...........................................................................................................II-238

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2(h)(1) Introduction16 First aid is emergency care provided for injury or sudden illness before professional emergency medical treatment is available. The first aid provider in the workplace is someone who is trained and experienced in the delivery of initial medical emergency procedures, using a limited amount of equipment to perform a primary assessment and intervention while awaiting arrival of emergency medical service (EMS) personnel. A workplace first aid program is part of a comprehensive safety and health management system consisting of the following four essential elements: • • • •

Management leadership and employee involvement; Worksite evaluation and analysis; Hazard and risk prevention and control; and Safety and health training.

Additionally, the fundamental elements for a first aid program at the workplace should include: • •

• • •

Identifying and assessing the workplace risks displaying the potential to cause worker injury or illness. Designing and implementing a workplace first aid program that: – aims to limit the outcome of accidents or exposures; and – includes sufficient quantities of appropriate and readily accessible first aid supplies and first aid equipment. Assigning and training first aid providers who: – receive first aid training suitable to the specific workplace; and – receive periodic refresher courses on first aid skills and knowledge. Familiarizing all workers with the first aid program, including what workers should do if a coworker is injured or ill. Establishing the policies and program in writing will assist with implementing this and other program elements. Providing for scheduled evaluation and changing of the first aid program to keep the program current and applicable to emerging risks in the workplace, including regular assessment of the adequacy of the first aid training course.

2(h)(2) First Aid Assessments17 First aid assessments must be conducted in each area and department to determine the appropriate first aid facilities and suitably trained people. The assessment should be documented in consultation with the first aider and a health and safety representative or expert with consideration to: •

Size, design, and layout of the facility or workplace;

16

Occupational Safety and Health Administration Best Practices Guide: Fundamentals of a Workplace First aid Program. 17 La Trobe University Occupational Health and Safety Manual, December 1999.

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The number and distribution of employees including arrangements such as shift work, after hours and field trips; The nature of hazards and the severity of the risk; The location of the workplace; and Known occurrences of accidents or illness.

. 2(h)(3) Elements of a First Aid Training Program18 There are a number of elements to include when planning a first aid training program for a particular workplace including: 1. Teaching Methods Training programs should consider and include the following principles: • • • • • • • •

Basing the curriculum on a consensus of scientific evidence where available; Having trainees develop “hands-on” skills through the use of mannequins and partner practice; Having proper first aid supplies and equipment available; Exposing trainees to acute injury and illness settings as well as to the appropriate response through the use of visual aids; Including a course information resource for reference both during and after training; Allowing adequate time for emphasis on frequently occurring situations; Emphasizing skills training and confidence-building over classroom lectures; and Emphasizing quick response to first aid situations.

2. Preparing to Respond to a Health Emergency The training program should include instruction or discussion in the following: • • • • • •

Prevention as a strategy in reducing and limiting fatalities, illnesses and injuries; Interacting with the existing local Emergency Management System (if available); Maintaining a current list of emergency telephone numbers (police, fire, ambulance, poison control) easily accessible by all employees; Understanding the legal aspects of providing first aid care, Understanding the effects of stress, fear of infection, panic; how they interfere with performance; and what to do to overcome these barriers to action; Learning the importance of universal precautions and body substance isolation to provide protection from blood-borne pathogens and other potentially infectious materials. Learning about personal protective equipment – gloves, eye protection, masks, and respiratory barrier devices. Appropriate management and disposal of blood-contaminated sharps and surfaces; and awareness of blood-borne Pathogens standard.

3. Evaluating the Scene and the Victim(s) An effective training program should include instruction in the following areas: 18

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Assessing the scene for safety, number of injured, and nature of the event; Assessing the toxic potential of the environment and the need for respiratory protection; Establishing the presence of a confined space and the need for respiratory protection and specialized training to perform a rescue; Prioritizing care when there are several injured; Assessing each victim for responsiveness, airway patency (blockage), breathing, circulation, and medical alert tags; Taking a victim’s history at the scene, including determining the mechanism of injury; Performing a logical head-to-toe check for injuries; Stressing the need to continuously monitor the victim; Emphasizing early activation of the Emergency Management System and emergency medical personnel; Indications for and methods of safely moving and rescuing victims; and Repositioning ill/injured victims to prevent further injury.

4. Responding to Life-Threatening Emergencies The training program should be designed or adapted for the specific worksite and may include first aid instruction in the following: • • • • • • • • • •

• •

Establishing responsiveness; Establishing and maintaining an open and clear airway; Performing rescue breathing; Treating airway obstruction in a conscious victim; Performing cardiopulmonary resuscitation (CPR); Using an automated external defibrillator (AED); Recognizing the signs and symptoms of shock and providing first aid for shock due to illness or injury; Assessing and treating a victim who has an unexplained change in level of consciousness or sudden illness; Controlling bleeding with direct pressure; Dealing with a variety of poisonings including: – Ingested poisons: alkali, acid, and systemic poisons. Role of the Poison Control Center; – Inhaled poisons: carbon monoxide; hydrogen sulfide; smoke; and other chemical fumes, vapors, and gases. Assessing the toxic potential of the environment and the need for respirators; – Knowledge of the chemicals at the worksite and of first aid and treatment for inhalation or ingestion; and – Effects of alcohol and illicit drugs so that the first aid provider can recognize the physiologic and behavioral effects of these substances. Recognizing asphyxiation and the danger of entering a confined space without proper respiratory protection. Additional training is required if first aid personnel will assist in the rescue from the confined space. Responding to wide-range of medical emergencies including: – Chest pain; II-233

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Stroke; Breathing problems; Anaphylactic reaction; Hypoglycemia in diabetics taking insulin; Seizures; Pregnancy complications; Abdominal injury; Reduced level of consciousness; and Impaled object.

5. Responding to Non-Life-Threatening Emergencies The training program should be designed for the specific worksite and to include first aid instruction for the management of the following: •

•

• •

• • •

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Wounds – Assessment and first aid for wounds including abrasions, cuts, lacerations, punctures, avulsions, amputations and crush injuries; – Principles of wound care, including infection precautions; and – Principles of body substance isolation, universal precautions and use of personal protective equipment. Burns – Assessing the severity of a burn; – Recognizing whether a burn is thermal, electrical, or chemical and how to administer the appropriate first aid; and – Reviewing corrosive chemicals at a specific worksite, along with administering the appropriate first aid. Temperature Extremes – Exposure to cold, including frostbite and hypothermia; and – Exposure to heat, including heat cramps, heat exhaustion and heat stroke. Musculoskeletal Injuries – Fractures; – Sprains, strains, contusions and cramps; – Head, neck, back and spinal injuries; and – Appropriate handling of amputated body parts. Eye injuries – First aid for eye injuries; – First aid for chemical burns. Oral Injuries – Lip and tongue injuries; broken and missing teeth; and – The importance of preventing aspiration of blood and/or teeth. Bites and Stings – Human and animal bites; and – Bites and stings from insects; instruction in first aid treatment of anaphylactic shock.

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2(h)(4) Periodic Program Updates19 The first aid program should be reviewed periodically to determine if it continues to address the current needs of the specific workplace. Training, supplies, equipment and first aid policies should be added or modified to account for changes in workplace safety and health hazards, worksite locations and worker schedules since the last program review. The first aid training program should be kept up-to-date with the latest first aid techniques and knowledge. Outdated training and reference materials should be replaced or removed from the workplace. 2(h)(5) First Aiders20 First aiders should be selected from those staff members whose duties normally do not remove them from the workplace. First aiders should be on-site at the workplace as often as possible. Additionally, prospective first aiders should be: • • • • • •

Staff who show evidence of enthusiasm and a ability to deal with injury and illness; Able to relate well to and communicate clearly with other staff; In reasonable health; Able to exercise sound judgment especially regarding the need to involve other support services; Able to be called away from their ordinary work and respond in short notice; and Appointed to the first aider role via their own free wi1l.

2(h)(6) First Aid Training and Certification21 First aiders assume the initial treatment of people suffering injury and illness. The treatment provided by first aiders should be consistent with their training and competency. When in doubt, a first aider should recommend that an injured employee seek medical advice. A first aider should not be responsible for ongoing care. In order to be effective, a workplace first aid in the training plan must cover the following issues and principles: • • • • • • • • •

Principals of First aid, Aims of first aid and priorities of care; Expired Air Resuscitation (EAR); Cardio Pulmonary resuscitation (CPR); Hygiene, infection control and medical waste removal; Reports and legalities; First aid kits; Practical decision making; Function of respiratory and circulatory systems; Cardiac emergencies;

19

Occupational Safety and Health Administration Best Practices Guide: Fundamentals of a Workplace First Aid Program. 20 La Trobe University Occupational Health and Safety Manual, December 1999. 21 Ibid.

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Secondary assessment & altered conscious state; Burns Fractures; theory and practical; Soft Tissue Injury; theory and practical; Head Injuries; Spinal Injuries; Eye Injuries; Respiratory emergencies; Asthma; hyperventilation; Diabetes, Stroke, Epilepsy, Allergic reactions; Poisoning; Moving a patient; and Material Safety Data Sheets and how to read them.

2(h)(7) First Aid for Electric Shock22 Shock is a common occupational hazard associated with working with electricity. A person who has stopped breathing is not necessarily dead but is in immediate danger. Life is dependent on oxygen, which is breathed into the lungs and then carried by the blood to every body cell. Since body cells cannot store oxygen and since the blood can hold only a limited amount (and only for a short time), death will surely result from continued lack of breathing. However, the heart may continue to beat for some time after breathing has stopped, and the blood may still be circulated to the body cells. Since the blood will, for a short time, contain a small supply of oxygen, the body cells will not die immediately. For a very few minutes, there is some chance that the person's life may be saved. The process by which a person who has stopped breathing can be saved is called artificial ventilation (respiration). The purpose of artificial respiration is to force air out of the lungs and into the lungs, in rhythmic alternation, until natural breathing is reestablished. Records show that seven out of ten victims of electric shock were revived when artificial respiration was started in less than three minutes. After three minutes, the chances of revival decrease rapidly. Artificial ventilation should be given only when the breathing has stopped. Do not give artificial ventilation to any person who is breathing naturally. You should not assume that an individual who is unconscious due to electrical shock has stopped breathing. To tell if someone suffering from an electrical shock is breathing, place your hands on the person's sides at the level of the lowest ribs. If the victim is breathing, you will usually be able to feel movement. Once it has been determined that breathing has stopped, the person nearest the victim should start the artificial ventilation without delay and send others for assistance and medical aid. The only logical, permissible delay is that required to free the victim from contact with the electricity in the quickest, safest way. This step must be done with enormous care; otherwise, the first aid responder may be injured.

22

Electricians Toolbox Etc., http://www.elec-toolbox.com/Safety/safety.htm

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In the case of portable electric tools, lights, appliances, equipment, or portable outlet extensions, the victim should be freed from contact with the electricity by turning off the supply switch or by removing the plug from its receptacle. If the switch or receptacle cannot be quickly located, the suspected electrical device may be pulled free of the victim. Other persons arriving on the scene must be clearly warned not to touch the suspected equipment until it is de-energized. The injured person should be pulled free of contact with stationary equipment (such as a bus bar) if the equipment cannot be quickly de-energized or if the survival of others relies on the electricity and prevents immediate shutdown of the circuits. This can be done quickly and easily by carefully applying the following procedures: 1. Protect yourself with dry insulating material. 2. Use a dry board, belt, clothing, or other available nonconductive material to free the victim from electrical contact. Do NOT touch the victim until the source of electricity has been removed. Once the victim has been removed from the electrical source, it should be determined whether the person is breathing. If the person is not breathing, a method of artificial respiration is used. Cardiopulmonary Resuscitation (CPR) CPR has been developed to provide aid to a person who has stopped breathing and suffered a cardiac arrest. The techniques are relatively easy to learn. Note: A heart that is in fibrillation cannot be restricted by closed chest cardiac massage. A special device called a defibrillator is available in some medical facilities and ambulance services. Muscular contractions are so severe with 200 milliamperes and over that the heart is forcibly clamped during the shock. This clamping prevents the heart from going into ventricular fibrillation, making the victim's chances for survival better. 2(h)(8) Skills Update First aid responders tend to experience long intervals between learning certain skills such as CPR and AED and actually using them. Numerous studies have shown a retention rate of only 6-12 months of these crucial, life-saving skills. Skill reviews and practice sessions are encouraged at least every 6 months for CPR and AED skills. Instructor-led retraining for life-threatening emergencies should occur at least annually. Retraining for non-life-threatening response should also occur periodically. 2(h)(9) First Aid Supplies23 It is important for the employer to give a specific person at the workplace the responsibility for choosing the types and amounts of first aid supplies and for maintaining those supplies. The supplies must be adequate, should address the kinds of injuries that commonly occur, and must 23

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be stored in an area where they are readily available for emergency access. An automated external defibrillator (AED) should be considered when selecting first aid supplies and equipment. Employers who have unique or revolving first aid needs should consider upgrading their first aid kits. Consultation with the local fire and rescue service or emergency medical professionals and experts may be beneficial. By assessing the specific needs of their workplaces, employers can ensure the availability of adequate first aid supplies. Employers should periodically reassess the demand for these supplies and adjust their inventories accordingly. 2(h)(10) Bibliography Accident Compensation Act 1985, Victorian Consolidated Legislation, http://www.austlii.edu.au/au/legis/vic/consol_act/aca1985204/. American Red Cross. First Aid: Responding to Emergencies. Third Edition. 2001. ANSI Z308.1-2003. Minimum Requirements for Workplace First Aid Kits. Arlington VA: InterNigerian Safety Equipment Association, 2003. American Heart Association, Heartsaver First Aid with CPR and AED, Publication 70-2562, Dallas: American Heart Association, 2002. American Heart Association in collaboration with InterNigerian Liaison Committee on Resuscitation, Guidelines 2000 for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care: InterNigerian Consensus on Science, Part 3: Adult Basic Life Support, Circulation. 2000; Vol. 102, Supplement I: I 22 - I 59. Electricians Toolbox Etc., http://www.elec-toolbox.com/Safety/safety.htm. La Trobe University, Occupational Health and Safety Manual, December 1999. Occupational Health and Safety Act of 2004, prepared by the Legislative Counsel Office, http://www.gov.pe.ca/law/statutes/pdf/o-01_01.pdf. Occupational Safety and Health Administration, Best Practices Guide: Fundamentals of a Workplace First aid Program, OSHA 3317-06N, 2006. Workplace Health and Safety Act 1995, Code of Practice, First Aid in the Workplace, http://www.legislation.qld.gov.au/LEGISLTN/CURRENT/W/WorkplHSaA95.pdf.

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SEC. 2(i) FIRE PROTECTION, EVACUATION, FIRST RESPONDER AND EMERGENCY PLANNING CONTENTS 2(i)(1) Flammability Properties ...........................................................................................II-241 2(i)(1)(i) General Information.............................................................................................. II-241 2(i)(1)(ii) Flammability Designation ................................................................................... II-244 2(i)(2) Ignition Temperature................................................................................................II-246 2(i)(3) Flammability Limits..................................................................................................II-247 2(i)(4) Vapor Density ............................................................................................................II-249 2(i)(5) Specific Gravity .........................................................................................................II-250 2(i)(6) Water Solubility.........................................................................................................II-250 2(i)(7) Responding to Fires...................................................................................................II-251 2(i)(8) Fire Fighting Agents..................................................................................................II-254 2(i)(8)(i) Water..................................................................................................................... II-254 2(i)(8)(ii) Foam .................................................................................................................... II-255 2(i)(8)(iii) Alcohol-Resistant Foams.................................................................................... II-257 2(i)(8)(iv) High Expansion Foams....................................................................................... II-257 2(i)(8)(v) Other Extinguishing Agents................................................................................. II-257 2(i)(8)(vi) Carbon Dioxide................................................................................................... II-258 2(i)(9) Electrical Fire Prevention.........................................................................................II-258 2(i)(10) Firefighting Guidance .............................................................................................II-259 2(i)(10)(i) Types................................................................................................................... II-259 2(i)(10)(ii) Firefighting Agents and Extinguishers .............................................................. II-260 2(i)(10)(iii) Vehicles ............................................................................................................ II-262 2(i)(10)(iv) Firefighting Gear .............................................................................................. II-262 2(i)(11) Specialized Rescue Procedures...............................................................................II-264 2(i)(12) First Responder to Electrical Fire Incidents.........................................................II-265 2(i)(13) Evacuation Planning ...............................................................................................II-266 2(i)(13)(i) Designated Roles and Responsibilities............................................................... II-266 2(i)(13)(ii) Preparation & Planning for Emergencies .......................................................... II-267 2(i)(13)(iii) Evacuation Procedure....................................................................................... II-267 2(i)(13)(iv) General.............................................................................................................. II-268 2(i)(13)(v) Template for Emergency Evacuation Plan ........................................................ II-268 2(i)(14) Bibliography.............................................................................................................II-270

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2(i)(1) Flammability Properties 2(i)(1)(i) General Information The majority of information organized in this subsection has been taken from the Handbook of Industrial Toxicology and Hazardous Materials for which permission has been granted. Two main categories of liquids are flammable and combustible, and are determined mainly by the liquid's flash point. Both categories of liquids will burn, but it is into which of these two categories the liquid belongs that determines its relative fire hazard. Flammable liquids are generally considered the more hazardous of the two categories mainly because they release ignitable vapors.24 A flammable material is any liquid having a flash point below 37.8°C. The U.S. Nigerian Fire Protection Agency (NFPA) expands this definition by including the stipulation that the vapor cannot exceed 275.79 kPa at a liquid temperature of 37.8°C, with the theory being that such liquids are capable of releasing vapor at a rate sufficient to be ignitable. Since this aspect of the definition relating to vapor pressure has little fire-ground application it is often ignored. However, it is important to note that if the heat from a fire raises the liquid temperature to a temperature above the liquid's flash point, it will automatically increase the vapor pressure inside a closed container. Any other source of sufficient heat will produce the same result. Within the combustible liquid category are those materials with a flash point above 37.8°C, Combustible liquids are considered less hazardous than flammable liquids because of their higher flash points. However, this statement can be misleading since there are circumstances when it is not a valid assumption. It is possible for certain combustible liquids to be at their flash point when a hot summer sun has been striking their metal container for some time. Additionally, during the transportation of some combustible products, the product is either preheated or a heat source is maintained to make the product more fluid than it would be at atmospheric temperatures. One reason this is done is to facilitate transportation or pumping; i.e. to aid with the movement of a material that is very viscous, such as asphalt or tar. Also, some materials classed as combustible solids will be heated to their melting point. Naphthalene is one example of this treatment. Naphthalene might be heated to a temperature above its melting point, which is about 80°C. Despite its fairly high ignition temperature (almost 526.7°C), it would not be unreasonable to surmise that a spill of liquid naphthalene could present a serious fire hazard. Fortunately, with naphthalene, quick action with adequate amounts of water applied as spray streams should cool and solidify it, thus greatly minimizing the fire risk. It is important to note that a combustible liquid at or above its flash point will behave in the same manner that a flammable liquid would in a similar emergency. As an example, No.2 fuel oil when heated to a temperature of 65.6°C can be expected to act or react in the same way gasoline would at 10°C. In most instances, however, to reach this elevated temperature will require the introduction of an external heat source. Some common examples of combustible petroleum liquids are given in Table 17.

24

Cheremisinoff, N. P., Handbook of Industrial Toxicology and Hazardous Materials, Marcel Dekker Publishers, New York, New York, 1999. Both the Publisher and Author hereby grant the Government of Nigeria the use materials reprinted in this section of the Nigerian Electricity Safety Standards.

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Table 17. Examples of Petroleum Liquids That Are Combustible

Product

Flash Point (°C)

Kerosene

37.8+

Fuel Oils

37.8 – 60

Diesel Oil

54.4

Lubricating Oil

148.9

Asphalt

204.4

It is important to note that the extinguishing techniques, controlling actions, or fire-prevention activities implemented can differ greatly depending upon which of the two categories the liquid falls in. To have the ability to categorize a liquid correctly when it is not so identified, it is only necessary to know its flash point. By definition, the flash point of a liquid determines whether a liquid is flammable or combustible. The categories of liquids are further subdivided into classes according to the flash point plus the boiling point of certain liquids. These divisions are summarized in Table 18, which shows that flammable liquids fall into Class 1, and combustible liquids into Classes 2 and 3. The products that are at the low end (37.8°C) of the Class 2 combustible-liquid group might be thought of as borderline cases. These could act very much like flammable liquids if atmospheric temperatures were in the same range. It is not a common industry practice to identify either stationary or portable (mobile) liquid containers by the class of liquid it contains. The usual practice is to label either "Flammable" or "Combustible" and include the required United Nations hazard placard. Table 18. Classes of Flammable and Combustible Liquids

Class

Flash Point (°C)

Boiling Point (°C)

1

Below 37.8

—

1A

Below 22.8

Below 37.8

1B

Below 22.8

At or above 37.8

1C

22.8-37.2

—

2

37.8-59.4

—

3

60 or above

Below 37.8

3A

60-92.8

At or above 137.8

3B

93.3 or above

—

Flash point is the temperature a liquid must be at before it will provide the fuel vapor required for a fire to ignite. A more technical definition for flash point is: The lowest temperature a liquid may be at and still have the capability of liberating flammable vapors at a sufficient rate that, when united with the proper amounts of air, the air-fuel mixture will flash if a source of ignition II-242

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is presented. The amounts of vapor being released at the exact flash-point temperature will not sustain the fire and, after flashing across the liquid surface, the flame will go out. It must be remembered that at the flash-point temperature, the liquid is releasing vapors and, as with other ordinary burnable materials, it is the vapors that burn. The burning process for both ordinary combustible solids and liquids requires the material to be vaporized. It may also be in the form of a very fine mist, which will be instantly vaporized if a source of heat is introduced. It is not the actual solid or the liquid that is burning, but the vapors being emitted from it. For this reason, when we speak of a fuel we are referring to the liberated vapor. It is an accepted phenomenon, assuming sufficient amounts of air to be present, that the greater the volume of released vapor, the larger the fire will be. The technical literature sometimes refers to the "fire point", which in most instances is just a few degrees above the flash point temperature, and is the temperature the liquid must be before the released vapor is in sufficient quantity to continue to burn, once ignited. However, because a flash fire will normally ignite any Class "A" combustible present in the path of the flash, it is reasonable to accept the flash point as being the critical liquid temperature in assessing a fire hazard. Any of the other combustibles ignited by the flash fire that is, wood, paper, cloth, etc., once burning, could then provide the additional heat necessary to bring the liquid to its fire point. A crucial objective upon arrival of the first responding fire forces is to determine if the liquid present is a product that is vaporizing at the time or, if it is not, and what condition may be present that is capable of providing the required heat to cause the liquid to reach its flash point. This information would have a direct influence on the selection of control and/or extinguishing activities. An emergency involving a petroleum liquid, which is equal to or above flash point, means that a fuel source consisting of flammable vapors will be present. This, in turn, means the responding fire-fighting forces will be faced with either a highly hazardous vapor cloud condition or with a fire if ignition has occurred before arriving at the scene. Conversely, if it is a liquid at a temperature below its flash point, then fuel would not be immediately available to burl. A source of air or more specifically, oxygen must be present. A reduction in the amount of available air to below ideal quantities causes the fire to diminish. Moreover, reduce the fuel quantity available and the fire will also diminish in size. Almost all extinguishing techniques developed are methods of denying the fire one or both of these requirements. By cooling a material below its flash point, vapor production is halted, thus removing the fuel from the fire. When utilizing a smothering-type extinguishing agent, the principle involved consists of altering the air-fuel mixture. When the vapor is no longer in its explosive range, the fire dies, either due to insufficient fuel or a lack of oxygen. The flash point tells us the conditions under which we can expect the fuel vapor to be created, but it is the explosive range which tells us that a certain mixture of fuel vapor and air is required for the vapor to become ignitable. The terms flammable limit and combustible limit are also used to describe the explosive range. These three terms have identical meanings and can be used interchangeably. This information is reported as the lower explosive limits (LEL) and the upper explosive limits (UEL). The values that are reported for the LEL and UEL are given as a percentage of the total volume of the air-fuel mixture. The area between the LEL and the UEL is

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what is known as the explosive range. The figures given for the amount of fuel vapor required to place a substance within its explosive range are shown as a percentage of the total air-fuel mixture. To compute how much air is required to achieve this mixture, subtract the listed percentage from 100 percent: the remainder will be the amount of air needed. Even though it is only the oxygen contained in the air that the fire consumes, flammable ranges are shown as airfuel ratios because it is the air that is so readily available. Any air-fuel mixture in which the vapor is above the UEL, or any air-fuel mixture in which the vapor is below the LEL, will not burn. Using gasoline as an example, the explosive range can be computed as follows, in Table 19. Table 19. Explosive Range of Gasoline

Gasoline vapor Air Total volume

LEL(%) 1.5 98.5 100

UEL (%) 7.6 92.4 100

This example helps to illustrate that large volumes of air are required to burn gasoline vapors. The explosive ranges for the different grades of gasoline, or even those of most other petroleum liquids, are such that average explosive-range figures that are suitable for use by the fire fighter would be the LEL at 1 percent and the UEL at about 7 percent. The vapor content of a contaminated atmosphere may be determined through the use of a combustible gas-detecting instrument, referred to as an explosimeter. If a fire involving a petroleum liquid does occur, an extinguishing technique that may be appropriate is the altering of the air-fuel mixture. One technique utilized will necessitate the use of an extinguishing agent such as a foam with the capability of restricting the air from uniting with the vapor. Another technique is to prevent the liquid from having the ability to generate vapor. Usually this is a cooling action and is accomplished with water spray streams. In both cases, extinguishment is accomplished as a result of altering the air-fuel mixture to a point below the LEL for the specific liquid. Flammability, the tendency of a material to burn, can only be subjectively defined. Many materials that we normally do not consider flammable will burn, given high enough temperatures. Neither can flammability be gauged by the heat content of materials. Fuel oil has a higher heat content than many materials considered more flammable because of their lower flashpoint. In fact, flashpoint has become the standard for gauging flammability. 2(i)(1)(ii) Flammability Designation The most common systems for designating flammability are the Department of Transportation (DOT) definitions, the Nigerian Fire Protection Association's (NFPA) system, and the Environmental Protection Agency's (EPA) Resource Conservation and Recovery Act's (RCRA) definition of ignitable wastes, all of which use flashpoint in their schemes. The NFPA diamond, which comprises the backbone of the NFPA Hazard Signal System, uses a four-quadrant diamond to display the hazards of a material. The top quadrant (red quadrant) contains flammability information in the form of numbers ranging from zero to four. Materials designated as zero will not burn. Materials designated as four rapidly or completely vaporize at atmospheric pressure and

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ambient temperature, and will burn readily (flashpoint <22.8°C and boiling point < 37.8°C). The NFPA defines a flammable liquid as one having a flashpoint of 93.3°C or lower, and divides these liquids into five categories: 1. Class IA: liquids with flashpoints below 22.8°C and boiling points below 37.8°C. An example of a Class 1A flammable liquid is n-pentane (NFPA Diamond: 4). 2. Class IB: liquids with flashpoints below 22.8°C and boiling points at or above 37.8°C. Examples of Class IB flammable liquids are benzene, gasoline, and acetone (NFPA Diamond: 3). 3. Class IC: liquids with flashpoints at or above 22.8°C and below 37.8°C. Examples of Class IC flammable liquids are turpentine and n-butyl acetate (NFPA Diamond: 3). 4. Class II: liquids with flashpoints at or above 37.8°C but below 60°C, Examples of Class II flammable liquids are kerosene and camphor oil (NFPA Diamond: 2). 5. Class III: liquids with flashpoints at or above 60°C but below 93.3°C. Examples of Class III liquids are creosote oils, phenol, and naphthalene. Liquids in this category are generally termed combustible rather than flammable (NFPA Diamond: 2). The DOT system designates those materials with a flashpoint of 37.8°C or less as flammable, those between 37.8°C and 93.3°C as combustible, and those with a flashpoint of greater than 93.3°C as nonflammable. EPA designates those wastes with a flashpoint of less than 60°C as ignitable hazardous wastes. The elements required for combustion are few – a substrate, oxygen, and a source of ignition. The substrate, or flammable material, occurs in many classes of compounds but most often is organic. Generally, compounds within a given class exhibit increasing heat contents with increasing molecular weights (MW). These designations serve as useful guides in storage, transport, and spill response. However, they do have limitations. Since these designations are somewhat arbitrary, it is useful to understand the basic concepts of flammability. Other properties specific to the substrate that are important in determining flammable hazards are the auto-ignition temperature, boiling point, vapor pressure, and vapor density. Auto-ignition temperature (the temperature at which a material will spontaneously ignite) is more important in preventing fire from spreading (e.g., knowing what fire protection is needed to keep temperatures below the ignition point) but can also be important in spill or material handling situations. For example, gasoline has been known to spontaneously ignite when spilled onto an overheated engine or manifold. The boiling point and vapor pressure of a material are important not only because vapors are more easily ignited than liquids, but also because vapors are more readily transportable than liquids (they may disperse, or when heavier than air, flow to a source of ignition and flash back). Vapors with densities greater than one do not tend to disperse but rather to settle into sumps, basements, depressions in the ground, or other low areas, thus representing active explosion hazards. Oxygen, the second requirement for combustion, is generally not limiting. Oxygen in the air is sufficient to support combustion of most materials within certain limits. These limitations are

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compound specific and are called the explosive limits in air. The upper and lower explosive limits (UEL and LEL) of several common materials are given in Table 20. Table 20. Explosive Limits of Hazardous Materials

Compound Acetone Acetylene Ammonia, Benzene Carbon monoxide Gasoline Hexane Toluene Vinyl chloride p-xylene

LEL % 2.15 2.50 16 1.30 12.4 1.4 1.1 1.2 3.6 1.0

UEL % 13 100 25 7.1 74 7.6 7.5 7.1 33 6.0

Flashpoint °C -20 Gas Gas -11.1 Gas -42.8 -21.7 4.4 Gas 32.2

Vapor Density 2.0 0.9 0.6 7.8 1.0 3-4 3.0 3.1 2.2 3.7

The source of ignition may be physical (such as a spark, electrical arc, small flame, cigarette, welding operation, or a hot piece of equipment), or it may be chemical in nature, such an exothermic reaction. In any case, when working with or storing flammables, controlling the source of ignition is often the easiest and safest way to avoid fires or explosions. Once a fire has started, control of the fire can be accomplished in several ways: through water systems (by reducing the temperature), carbon dioxide or foam systems (by limiting oxygen), or through removal of the substrate (by shutting off valves or other controls). Chapter 4 provides detailed discussion on the theories of fire and specific information on hydrocarbons, as well as chemical specific fire characteristics. 2(i)(2) Ignition Temperature Consider the emergency situation where there is a spill of gasoline. We may immediately conclude that two of the requirements for a fire exist. First, the gasoline, which would be at a temperature above its flash point, will be releasing flammable vapors; thus a source of fuel will be present. Moreover, there is ample air available to unite with the fuel thus there is the potential for the mixture to be in its explosive range. The only remaining requirement needed to have a fire is a source of heat at or above the ignition temperature of gasoline. Technically speaking, all flammable vapors have an exact minimum temperature that has the capability of igniting the specific air-vapor mixture in question. This characteristic is referred to as the ignition temperature and could range from as low as 148.9°C for the vapor from certain naphthas to over 482.2°C for asphaltic material vapor. Gasoline vapor is about halfway between, at 315.6°C. A rule of thumb for the ignition temperature of petroleum-liquid vapors is 260°C. This figure may appear low for several of the hydrocarbon vapors, but it is higher than that of most ordinary combustibles, and is close enough to the actual ignition temperatures of the products most frequently present at emergency scenes to give a suitable margin of safety.

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In emergency situations, it is best to take conservative approaches by assuming that all heat sources are of a temperature above the ignition temperature of whatever liquid may be present. This approach is not an overreaction when it is realized that almost all the normally encountered spark or heat sources are well above the ignition temperature of whatever petroleum liquid might be present. Among the more common sources of ignition would be smoking materials of any kind (cigarettes, cigars, etc.), motor vehicles, and equipment powered by internal combustion engines: also electrically operated tools or equipment, as well as open-flame devices such as torches and flares. The removal of any and all potential ignition sources from the area must be instituted immediately and methodically. The operation of any motor vehicle, including dieselpowered vehicles, must not be permitted within the immediate vicinity of either a leak or spill of a flammable liquid. The probability of a spark from one of the many possible sources on a motor vehicle is always present. Also, under no circumstances should motor vehicles be allowed to drive through a spill of a petroleum product. Ignition sources are not necessarily an external source of heat; it could be the temperature of the liquid itself. Refineries and chemical plants frequently operate processing equipment that contains a liquid above its respective ignition temperature. Under normal operating conditions, when the involved liquid is totally contained within the equipment, no problems are presented because the container or piping is completely filled with either liquid or vapor. If full and totally enclosed, it means there can be no air present; thus an explosive or ignitable mixture cannot be formed. If the enclosed liquid, which in certain stages of its processing, may be above the required ignition temperature should be released to the atmosphere, there is a possibility that a vapor-air mixture could be formed and hence, ignition could occur. This type of ignition is referred to as auto-ignition. Auto-ignition is defined as the self-ignition of the vapors emitted by a liquid heated above its ignition temperature and that, when escaping into the atmosphere, enter into their explosive range. Some typical ignition temperatures for various petroleum liquids are 315.6°C for gasoline, 287.8°C for naphtha and petroleum ethers, 210°C for kerosene, and 385°C for methanol. From the above discussions, the important elements that are responsible for a fire are: • • •

Fuel in the form of a vapor that is emitted when a liquid is at or above its flash point temperature. Air that must combine with the vapor in the correct amounts to place the mixture in the explosive range. Heat, which must be at least as hot as the ignition temperature, must then be introduced.

2(i)(3) Flammability Limits Petroleum liquids have certain characteristics that can exert an influence on the behavior of the liquid and or vapor that is causing the problem. For this reason, these features may have a bearing on the choice of control practices or extinguishing agents under consideration. These characteristics include the weight of the vapor, the weight of the liquid, and whether the liquid will mix readily with water. The specific properties of importance are vapor density, specific gravity, and water solubility. Before discussing these important physical properties, let's first examine the data in Table 21 which lists the flammability limits of some common gases and liquids. Two general conclusions can be drawn. First, the lower the material's LEL, obviously the II-247

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more hazardous. Also note that there are some materials that have wide explosive ranges. This aspect is also significant from a fire standpoint. As an example, comparing hydrogen sulfide to benzene, although the LEL for H2S is more than 3 times greater, its explosive range is 7 times wider. This would suggest that H2S is an extremely hazardous material even though its LEL is relatively high. In fact, H2S fires are generally so dangerous that the usual practice is to contain and allow burning to go to completion rather than to fight the fire. Table 21. Limits of Flammability of Gases and Vapors, % in Air

Gas or Vapor

LEL

UEL

Hydrogen

4.00

75.0

Carbon monoxide

12.5

74.0

Ammonia

15.5

26.60

Hydrogen sulfide

4.30

45.50

Carbon disulfide

1.25

44.0

Methane

5.30

14.0

Ethane

3.00

12.5

Propane

2.20

9.5

Butane

1.90

8.5

Iso-butane

1.80

8.4

Pentane

1.50

7.80

Iso-pentane

1.40

7.6

Hexane

1.20

7.5

Heptane

1.20

6.7

Octane

1.00

3.20

Nonane

0.83

2.90

Decane

0.67

2.60

Dodecane

0.60

Tetradecane

0.50

Ethylene

3.1

32.0

Propylene

2.4

10.3

Butadiene

2.00

11.50

Butylene

1.98

9.65

Amylene

1.65

7.70

Acetylene

2.50

81.00

Allylene

1.74

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Gas or Vapor

LEL

UEL

Benzene

1.4

7.1

Toluene

1.27

6.75

Styrene

1.10

6.10

o-Xylene

1.00

6.00

Naphthalene

0.90

Antluacene

0.63

Cyclo-propane

2.40

10.4

Cyclo-hexene

1.22

4.81

Cyclo-hexane

1.30

8.0

Methyl cyclo-hexane

1.20

Gasoline-regular

1.40

7.50

Gasoline-73 octane

1.50

7.40

Gasoline-92 octane

1.50

7.60

Gasoline-100 octane Naphtha

1.45 1.10

7.50 6.00

2(i)(4) Vapor Density Vapor density is a measure of the relative weight of vapor compared to the weight of air. Published data on the characteristics of petroleum products usually include the vapor density. The value of unity has been arbitrarily assigned as the weight of air. Hence any vapor that is reported to have a density of greater than 1 is heavier than air, and any vapor with a density of less than 1 is lighter than air. Vapors weighing more than 1 will usually flow like water, and those weighing less will drift readily off into the surrounding atmosphere. Even heavier-than-air flammable petroleum-liquid vapor can be carried along with very slight air currents. It may spread long distances before becoming so diluted with enough air as to place it below the lower explosive limit (LEL), at which time it would become incapable of being ignited. There are catastrophic incidences that have occurred whereby ignitable air-vapor mixtures have been detected as far as one-half mile from the vapor source. For this reason, while responding to a spill or leak, we must consider environmental and topographical features of the surroundings, such as wind direction, the slope of the ground, any natural or artificial barriers that may channel the liquid or vapors. It is critical in a non-fire incident such as a spill or leak to determine the type of petroleum liquid present and its source. Information about the material's vapor density enables us to make reasonable predictions as to the possible behavior of the emitting vapor. These factors may influence the route of approach, the positioning of firefighting apparatus and personnel, the need for and the route of evacuation, and the boundaries of the potential problem area. It is essential that no apparatus or other motor vehicles or personnel be located in the path that a vapor cloud will most likely follow.

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As a rule of thumb one should approach a hydrocarbon spill (non-fire situation) under the assumption that the liquid is vaporizing (the vapors will be invisible) and that the liberated vapors are heavier than air unless proven otherwise. The expected conduct of a heavier-than-air vapor is for it to drop and spread at or below ground level much as a liquid would. The big difference is that a liquid will be visible and its boundaries well defined. One can expect that the invisible heavier-than-air vapor will settle and collect in low spots such as ditches, basements, sewers, etc. As the vapor travels, it will be mixing with the air, thus some portions of the cloud may be too rich to burn, other sections too lean, and still others well within the explosive range. Some typical vapor densities for petroleum products are 3 to 4 for gasoline, 2.5 for naphtha, and 1.1 for methanol. For comparison, the vapor density for hydrogen gas is 0.1. 2(i)(5) Specific Gravity The property of specific gravity indicates a petroleum liquid's weight relative to the weight of an equal volume of water. The specific gravity of water is assigned the value of unity as a reference point. Hence, other liquids are evaluated relative to water; those lighter than water have a value less t11an unity, whereas those that are heavier have a value that is greater than unity. In general, petroleum products are lighter than water; as a result, they can be expected to float on and spread over the water's surface. The exceptions to this are thick, viscous materials such as road tars and heavy "bunker" fuel. With their low specific gravity, most petroleum liquids, if spilled onto a pool of water, have a tendency to spread quickly across the water's surface. Unless the fluid contacts an obstacle, the oil will continue to spread until it is of microscopic thickness. For this reason, a relatively small amount of oil floating on water is capable of covering a large area of the surface. In a spill situation, knowledge of the liquid's specific gravity can help determine which one of several tactics will be implemented to mitigate the spread of contamination or to eliminate a fire hazard. Knowing the specific gravity will help determine the following: • • •

If it will be possible to use only water, or must we apply a different agent for purposes of smothering the fire. How great the probability is that the burning liquid could result in the involvement of exposures because of it floating on any water that is applied. Can the displacement of the fuel by water be considered an effective technique to control a leak from a container?

Some specific gravities of common petroleum liquids are 1 to 1.1 for asphalt, 0.8 for gasoline, and 0.6 for naphtha. 2(i)(6) Water Solubility Another important property is water solubility, which may be described as the ability of a liquid to mix with water. Since most petroleum products are lighter than water, and even if they are well mixed with water, they will separate into a layer of water and a layer of the hydrocarbon. Exceptions to this are polar solvents such as methanol and other alcohols. These types of materials will readily mix with water and can even become diluted by it.

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Information on solubility is important in an emergency situation because a petroleum fire will require the application of a regular-type foam or an alcohol-resistant-type foam for extinguishment or for vapor-suppression purposes. For use on a water-soluble liquid, a goodquality alcohol-resistant foam is generally applied. 2(i)(7) Responding to Fires In an emergency situation involving a flammable liquid, the product can be expected to behave as follows: • • • •

When accidentally released from its container it almost always results in a fire response. If a fire does occur, flammable liquids prove to be virtually impossible to extinguish by cooling with water. If the liquid is contained, the confined space will consist of a vapor-rich mixture. After extinguishment, there is still the strong possibility for a reflash owing to the continued production of vapor.

It is important to remember that during an emergency the escaping flammable liquids are lowflash products and, as a result, are releasing vapor at the usual atmospheric temperatures. These materials are, therefore, very susceptible to ignition. Because of this, they are generally encountered as an event requiring fire-control procedures. Also, for the same reasons, and the frequent need for large quantities of chemical extinguishing agents, they can present difficult extinguishment problems. The fact that the temperature at which many flammable liquids release vapor is well below the temperature of the water that is being used for fire-control purposes means that extinguishment by the cooling method is not feasible. This does not mean water cannot be used. In fact, the use of water serves an important function in spite of its limitations. However, to obtain extinguishment other tactics utilizing a different agent and techniques are needed. Exactly what agent and what technique will be dictated by the size of the fire, the type of storage container or processing equipment involved, and the fire-fighting resources that are available. When dealing with a low flash point flammable liquid, the probability of a reflash occurring after initial extinguishment is achieved is a high probability. The probability of an ignitable air-fuel mixture existing inside a closed storage container of a flammable liquid is normally low. Flammable liquids have the capacity of generating vapor below the commonly encountered atmospheric temperatures; thus, the space between the tank top and the liquid surface will most usually contain a vapor-rich atmosphere (i.e., conditions will be above the UEL). As the vapor being liberated drives the air from the container, the vapor-rich mixture being above the UEL cannot be ignited; moreover, if a fire should occur outside the tank or vessel, it will not propagate a flame back into the tank. The major exceptions would be those instances where the product had a flash point temperature about the same as the prevailing atmospheric temperature. Another example would be when a tank containing a low vapor pressure product with a flash point in the same range as the prevailing atmospheric temperature is suddenly cooled. A thunderstorm accompanied by a downpour of rain could cause the tank to breathe in air if the liquid is cooled below the temperature at which it is capable of emitting vapor (the boiling point).

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In contrast to flammable liquids, an emergency situation that involves a combustible liquid will have a much different behavior. The expected behavior of a combustible product would be for: • • •

the liquid to present no significant vapor problem; a fire to be readily extinguished by cooling the liquid with water; and the atmosphere above the liquid level to be below the LEL of any confined product.

Most combustible liquids do not present a vapor problem if accidentally released into the atmosphere. The probability of a fire, therefore, is considerably less than it would be if the spill was of a flammable material. If, however, the combustible liquid is at a temperature higher than its flash point, then it can be expected to behave in the identical manner of a flammable liquid. One major difference between the two in a fire situation is that the potential exists for cooling the combustible liquid below its flash point by the proper application of water (generally applied in the form of water spray). In the event the liquid is burning, and if the fire forces are successful in achieving the required reduction in liquid temperature, then vapor production will cease and the fire will be extinguished because of a lack of vapor fuel. Unless this reduction in liquid temperature can be brought about, the fire will necessitate the same control considerations a lowflash liquid fire would. With a fire in a storage tank containing a combustible liquid, normally the application of a foam blanket is the only practical method to achieve extinguishment. This is normally done when the entire exposed surface is burning and is necessitated by the fact that the sheer size of the fire makes it very difficult to apply water spray in the amounts and at the locations needed. Also, the volume of oil that has become heated is such that the large quantities of water needed to cool the liquid would introduce the possibility of overflowing the tank. Another problem is that the water requirements for both protecting exposures and attempting extinguishment might be far greater than what is available. These factors alone would cause the emergency forces to treat all refined product tank fires alike and, regardless of the flash point of the liquid, initiate the required steps to apply a foam blanket to the liquid surface. In addition there is always concern for any reaction the water may cause when contacting an oil or hydrocarbon heated above the boiling point of water (212°F). In general, because a spill is generally shallow, spilled or splashed combustible liquids do not present the type of problems that a large storage tank does. It is reasonable to expect to be able to extinguish shallow pools or surface spills with water spray. In the case of a storage tank with a combustible product, the atmosphere inside the container will normally consist of air. On occasion, there will be detectable odors such as that associated with fuel oil. These odors, which are a good indicator of the presence of a combustible product, are not considered fuel vapor. During a fire situation, flame impingement or radiant heat on a container could cause the liquid to become heated to the temperature at which it would emit vapors. Should this occur, and the vapors being generated then start to mix with the air already in the tank, at some instant the space in the container would then contain a mixture that was within the explosive range of the product; if ignition occurred, a forceful internal explosion could result. The case of crude oil is somewhat unique compared to fires with refined petroleum products. Burning crude oil has the capability of developing a "heat wave". Crude oil has a composition of different fractions of petroleum products. In a manner similar to a refinery operation which

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distills, or heats crude oil to separate it into the various usable products - such as gasoline and asphalt, a fire accomplishes the same effect. As crude oil burns it releases the fractions that have lower flash points first, and these are burned. The heavier fractions sink down into the heated oil. This movement of light fractions up to the fire and heavier, heated fractions down into the crude produces the phenomenon known as a heat wave. Crude oil has the same basic characteristics as other flammable liquids. There are different grades of crude oil produced from various geographic locations throughout the world, with some crudes having more heavy-asphalt type material than others. Some have greater quantities of sulfur (creating the problem of poisonous hydrogen sulfide gas generation during a fire) and still others more light, gaseous fractions; however, a common characteristic among them is that all will have varying amounts of impurities and some entrained water. When liquids of this type burn, creating a heat wave which is comprised of the higher boiling point components plus whatever impurities may be present in the product, radiant heat from the flame heats the liquid surface, the light products boil-off, thus creating the vapor that is burning. The remaining hot, heavier materials transfer their heat down into the oil. As it is formed, this heat wave, or layer of heated crude oil components, can reach temperatures as high as 315.6°C and spread downward at a rate of from 30.5 to 45.7 centimeters per hour faster than the burn-off rate of the crude oil. This would mean that with a crude oil burn-off of 30.5 centimeters per hour, at the end of two hours the heat wave would be somewhere between 61.0 and 91.4 centimeters thick. Once this heat wave is created, the chances of extinguishing a crude-oil tank fire, unless it is of small size, are poor, and any water or foam applied could result in a "slopover" of burning oil. Crude oil normal contains some entrained water and/or an emulsion layer of water and oil. In addition, crude-oil storage tanks will have some accumulations of water on the uneven tank bottoms. In a fire, when a heat wave is formed and comes in contact with any water, a steam explosion will occur, thus agitating the hot oil above it with great force. The evolution of the steam explosion can be attributed to the reaction of water to high temperatures. When water is heated to its boiling point of 100°C, water vapor or steam is generated. Steam that is produced expands approximately 1700 times in volume over the volume of the water that boils away. If a heat wave of a temperature well above 100°C contacts any water entrained in the oil, or some of the bottom water, which is usually in larger quantities, the instantaneous generation of steam will act like a piston, causing the oil to be flung upward with considerable violence and force. This reaction is so strong that it causes the oil to overflow the tank shell. This sudden eruption is known as a boilover. When the hot oil and steam reaction takes place, the oil is made frothy, this in turn further increases its volume. The reaction resulting from the heat wave contacting entrained water can be expected to be of lesser activity than from contact with bottom water. The reason for this difference is that the quantities of water converted to steam in a given spot are usually less. Another phenomenon associated with a crude oil fire is slopover. Basically, the same principles that are responsible for a boilover are the cause of a slopover. The fundamental difference is that in a slopover the reaction is from water that has entered the tank since the start of the fire. Usually this introduction is the result of firefighting activities. A slopover will occur at some point after the heat wave has been formed. Either the water from the hose streams or, after the

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bubbles collapse, the water in the foam will sink into the oil, contacting the heat wave, where it is converted to steam, and the agitation of the liquid surface spills some amount of oil over the tank rim. The proper extinguishing agents suitable for petroleum liquid emergencies must be capable of performing the identical functions as those agents used in the combating of structural-type fires. There will be times when circumstances dictate the use of a cooling agent, whereas at other times it will be a smothering agent, and on some occasions, both agents will be necessary. There are a variety of agents capable of accomplishing each of these objectives, as well as being appropriate to combat Class B-type fires. Agents suitable for use on Class B-type fires include halon, carbon dioxide (COD), dry chemicals, foam, and aqueous film forming foam. A description of the major types of fire fighting agents is given below. 2(i)(8) Fire Fighting Agents 2(i)(8)(i) Water For chemical fires water can be used for the dissipation of vapors, for the cooling of exposed equipment, for the protection of personnel, for control purposes, and, for actual extinguishment. For the cooling down of exposed equipment such as pipelines, pinups, or valves, it is recommended that water be applied at the minimum flow rate of 3.8 liters per minute per 10 square feet of exposed surface area. Some general guidelines to consider when applying water are as follows: • • • • • •

All areas of any piping, containers, etc., that are exposed to the fire's heat or flame should be kept wetted during the course of the fire. The use of water streams to push and move the burning liquid away from exposed equipment is recommended provided that it can be done safely. The rate of flow from any hose stream should not be less than 378.4 l/min regardless of its purpose. The use of spray streams is recommended whenever possible. Back-up lines for lines in active service should be provided and they should be at least of the same capacity as the attack line. Any equipment being protected is cool enough if water applied to it no longer turns to steam.

With storage tanks or processing equipment exposed to fire or radiant heat, the cooling of any metal above the liquid level inside the vessel is critical. Metal surfaces that have a constant film of water flowing over them will not reach a surface temperature above the boiling point of water. This temperature is well below that which would subject the metal to loss of integrity because of softening. Water flows employed to cool exposed vertical storage tanks can be calculated using as a requirement one hose line (flowing 756.9 l/min) per 3.0 meters of tank diameter. Assuming an average tank height of 15.2 feet, this would give a water flow capability in excess of the recommended rate. On the fire ground, wind conditions, personnel deficiencies (fatigue, lack of experience or training, etc.), strewn feathering, and so forth have historically resulted in not all

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the water that is flowing actually doing its intended function. The rule of thumb of one line flowing a minimum of 756.9 l/min for each 3.0 meters of tank diameter provides a suitable safety margin to overcome the loss of water not reaching its target. This flow is only required on the side or sides of the tank being heated; therefore, if a 30.5-meter-diameter tank is receiving heat on just one-half of its circumference, it would require five hose streams of 756.9 l/min, each applied to the heated area for cooling purposes. It must be anticipated that these minimum flows will need to be maintained for a time period of at least 60 minutes. Tank truck incidents in which the fire burned for several hours are not unusual. It should be appreciated that a relatively minor fire on a tank truck or rail car could require in excess of 75,686 liters of water for control and/or extinguishment. It is imperative that as early into the event as possible, an accurate assessment of water flow requirements should be made and flow rates adjusted accordingly. First responders must be constantly alert for any indication of an increase in the internal pressure of a container. Such an increase or any visible outward distortion of the tank shell would be an indication that additional water flows are required. These warning signs, which would be an indication of increased internal pressures, could justify the immediate use of unmanned monitors or hoseholders, larger size nozzles, and the pulling back of all personnel to a safe location. In preparing emergency response plans for petroleum liquid spills or fires, it should be taken into consideration that the required water rates could be needed for long periods of time. Built into the plans must be provisions for an uninterrupted supply at a suitable volume. The rates stipulated in the foregoing do not include amounts of water that may be needed for the protection of fire-fighting personnel who are involved in activities such as rescue work or valve closing and block off operations. If these or other water-consuming activities are required, additional water must be provided. Of equal importance to the amount of water being used is that water be used in the right place. In general, to application of water should have as its objective one or more of the following goals: • • • •

The cooling of the shell of any container that is being subjected to high heat levels. This is most effectively accomplished by applying the water to the uppermost portions of the container and allowing it to cascade down the sides. The cooling of any piece of closed-in equipment containing a liquid or gas and exposed to high heat levels. This is most effectively accomplished by applying the water spray over the entire area being heated. The protection of any part of a container, piping, or item of processing equipment receiving direct time contact. This is most effectively accomplished with a very narrow spray pattern or even a straight stream directed at the point of flame contact. The cooling of steel supports of any container or pipe rack that may be subjected to high heat levels. This is most effectively accomplished by the application of narrow spray streams to the highest part of the support being heated and permitting the water to run down the vertical length of the support.

2(i)(8)(ii) Foam The application of a foam blanket is the only means available to the fire forces for the extinguishment of large petroleum storage tank fires. The foam blanket extinguishes by preventing vapor, rising from the liquid surface, from uniting with the surrounding air and forming a flammable mixture. Although the water in a foam does provide some incidental II-255

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cooling action, this is considered of more importance for cooling heated metal parts, thus reducing the possibility of re-ignition, than as an extinguishing factor. A good-quality foam blanket of several inches in thickness has also been proved effective as a vapor suppressant on low flash-point liquids. Foam may also be used to suppress vapor, hence the layer of foam will be instrumental both in preventing ignition and reducing the contamination of the surrounding atmosphere. Since foam is still water, even if in a different form from that usually used, it may conduct electricity: consequently, its use on live electrical equipment is not recommended. There are basically two methods of foam application to fires. The first involves the application of chemical foam, which is generated from the reaction of a powder with water. This type of foam has been replaced largely by a technique that involves the formation of foam bubbles when a foaming agent and water are expanded by the mechanical introduction of air. This type, which is not a chemical reaction, is referred to as mechanical foam. Another name for the same material is air-foam. There are a variety of foam concentrates designed to fit different hazards. These include regular protein-based foams, fluoroprotein foams, aqueous film forming types, alcoholresistant types, as well as foams that are compatible with dry chemical powders and those that will not freeze at below-zero temperatures. Of the many types, the most suitable for general allaround petroleum the use would be either a good-quality fluoroprotein or a good-quality aqueous film forming foam (AFFF). Foam liquids are also available in a wide range of concentrates, from 1 percent to 10 percent. The 3 percent and 6 percent protein and fluoroprotein types are usually employed as low-expansion agents with an expansion ratio of about 8 to 1. That is, for each 378.4 liters of foam solution (water/concentrate mix) to which air is properly introduced, it will then develop approximately 3,027.4 liters of finished foam. Foam concentrates of other than 3 percent or 6 percent generally are either high-expansion (as high as 1,000 to 1) or alcoholresistant types. In foam applications, the manufacturer will provide a percentage rating of a concentrate, which identifies the quantity of concentrate required to be added to water to achieve a correct solution mixture. For each 378.4 liters of solution flowing, a concentrate rated as 3 percent would mean 3 gallons of concentrate per 367.1 liters of water, whereas a 6 percent concentrate would mix with 355.7 liters of water. This readily explains why only half as much space is required to store or transport the amount of 3 percent concentrate needed to generate a given quantity of foam than would be needed for a 6 percent concentrate to make the same volume of foam. Once the application of foam is initiated, it must be applied as gently as possible in order to develop a good vapor-tight blanket on the liquid surface. Any agitation of the foam blanket or of the burning liquid surface will serve to prolong the operation and to waste foam supplies. Water streams cannot be directed into the foam blanket or across the foam streams because the water will dilute and break down the foam. To be assured that all metal surfaces are cool enough and a good, thick (10.2 centimeters or more) blanket of foam has been applied, continue application for a minimum of five minutes after all visible fire is extinguished. One of the agents considered suitable for the extinguishment of petroleum-liquid fires is aqueous film forming foam. This is a liquid concentrate that contains a fluorocarbon surfactant to help float and spread the film across the petroleum-liquid surface and is commonly referred to as "A Triple F". AFFF concentrates of 1, 3, or 6 percent are available, all with about an 8 to 1 expansion ratio. This material is one of the mechanical-type foaming agents. The same kind of

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air-aspirating nozzles and proportioners that are used for protein-based foams are usable with AFFF concentrates. The primary advantage of AFFF over other foaming agents is its ability to form a thin aqueous film that travels ahead of the usual foam bubbles. This film has the ability to flow rapidly across the burning liquid surface, thus extinguishing the tire by excluding the air as it moves across the surface. The regular foam bubbles formed and flowing behind the film have good securing qualities, which serve to prevent rehashing from occurring. As with all types of foams, care must be exercised that the foam blanket, once formed, is not disturbed. Water streams should not be directed into the foam blanket or onto the same target a foam stream is aimed at. Water will dilute the foam below the needed concentration and, simultaneously, the force of the stream will destroy the foam's blanketing effect. The blanket must be maintained until all flames are extinguished, all heated metal surfaces cooled, and other sources of ignition removed from the vicinity. 2(i)(8)(iii) Alcohol-Resistant Foams Foams that are suitable for water-soluble polar solvents are formulated to produce a bubble that is stable in those fuels and tends to mix and unite with water. Fuels of this type dissolve the water contained in regular foam very rapidly resulting in the collapse of the bubbles. The breakdown is so fast and complete with regular protein or fluoroprotein based foams that unless the rate at which the foam is being applied is well above the recommended rate, the blanket will not form at all. Alcohol-type foam concentrates are most commonly available at strengths of 3 percent, 6 percent, or 10 percent. Because of the possibility of breakdown, regular foams are not considered suitable for polar solvent-type fires. The exception would be a fire in a container of fairly small diameter or a shallow spill, either of which would allow for the possibility of applying foam at sufficient rates to the point of overwhelming the tire. 2(i)(8)(iv) High Expansion Foams High-expansion foam includes foaming agents with the expansion ratio between the solution and the foam bubbles of from 20 to 1 to as high as 1,000 to 1. This agent has been found suitable when combating certain types of Class A and Class B fires. Originally developed to help fight fires inside mines, it is most effective when used in confined areas. Extinguishment is accomplished both by the smothering action of the foam blanket and the cooling action obtained from the water as the bubbles break down. Light, fluffy bubbles break apart and are easily dispersed by even relatively moderate wind currents. Bubbles formed at ratios greater than about 400 to 1 are most likely to be adversely affected by regular air movement as well as the thermal updrafts created by the fire. In an effort to overcome the susceptibility of the bubbles to wind currents, medium expansion foams have been introduced, which have expansion ratios ranging from about 20:1 to 200:1. High-expansion foam concentrates require special foam generators both for proportioning the liquid with water, and aspirating the mixture. Many high expansion foam-dispensing devices have a discharge range of only a few feet; thus, they must be operated fairly close to the area being blanketed. 2(i)(8)(v) Other Extinguishing Agents Other extinguishing agents that are suitable for use on fires involving petroleum liquids include dry chemical powders, carbon dioxide gas, and halon gases. Each of these agents, while being

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capable of extinguishing Class B fires, usually is available in either hand-held extinguishers or the larger wheeled or trailer-mounted portable units. In some petroleum refineries or chemical plants, an on-site fire brigade that is equipped with an apparatus capable of dispensing large volumes of dry chemical, or a vehicle with a large-capacity carbon dioxide (CO2) cylinder is common practice. 2(i)(8)(vi) Carbon Dioxide Carbon Dioxide (CO2) is used in fighting electrical fires. It is nonconductive and, therefore, the safest to use in terms of electrical safety. It also offers the least likelihood of damaging equipment. However, if the discharge horn of a CO2 extinguisher is allowed to accidentally touch an energized circuit, the horn may transmit a shock to the person handling the extinguisher. The very qualities which cause CO2 to be a valuable extinguishing agent also make it dangerous to life. When it replaces oxygen in the air to the extent that combustion cannot be sustained, respiration also cannot be sustained. Exposure of a person to an atmosphere of high concentration of CO2 will cause suffocation. 2(i)(9) Electrical Fire Prevention To prevent electrical fires, pay special attention to the following areas. •

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Against short circuit: Electrical short circuit has three situations: grounding short-circuit, short-circuit between the lines, and completely short-circuit. – To prevent short circuits: (1) Install electrical equipment according to the circuit voltage, current strength and the use of nature, correct wiring. In acidic, hot or humid places, it is necessary to use acid with anti-corrosion, high temperature and moisture-resistant wires. Traverse firmly installed to prevent shedding and should not be tied into wire or wires tightly knotting hung on the wire or nails. (2) Mobile power tools wire, a good layer of protection to prevent the mechanical damage, loss. (3) No bare wire inserted in the socket on the end. (4) Power master switch, the switch should be installed for the use of the current strength of the insurance unit, and conduct periodic current operation to eliminate hidden perils. Prevent overloads: Various conductors have certain load, when the load current intensity over Traverse, Traverse temperature surge, insulating layer can lead to fire. Prevent circuit overload by: (1) Ensure that all electrical equipment are in strict accordance with the electrical safety codes matching the corresponding wires, and the correct installation, are not allowed to randomly indiscriminate access. (2) Check to see that the appropriate use of load is induced on wires. Make sure that electrical equipment do not exceed load limitations, and that production levels and needs have separation, control use. (3) To prevent single-phase three-phase motor running, it is necessary to install three-phase switching single-phase power distribution boards running lights. (4) Circuit master switch, the switch should be installed in traffic safety and wire line Fusing easy for the insurance. Anti-contact resistance: When a conductor with another wire or wires and switches, protective devices, meters and electrical connections are exposed, they form a resistance,

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called contact resistance. If the contact resistance is too large, then when the current is passed it will result in heating to the point where the wire insulation layers will catch on fire, metal wire fuse, and sparks are generated. If there is any source of fuel in close proximity then the potential for a fire exists. To avoid this: (1) all connections should be secured and layers should be thoroughly clean of grease, dirt and oxide films. (2) Apply 6-102 mm cross-sectional area of wire, welding method of connecting. 102 mm cross section above the wire should be connected by wiring tablets. (3) Regular line connections should be made and any connections found to be tap loose or hot should be immediately corrected. Check electrical equipment regularly for sparks or arcing. These conditions can trigger spontaneous combustion of flammable gases or cause dust explosions. To prevent electrical equipment from contributing to fires: (1) Conduct regular inspections of insulation resistance and monitor the quality of insulation layers. (2) Inspect and correct naked wires and metal contacts to prevent short circuit. (3) Install explosion-proof seals or isolated lighting fixtures, switches and protective devices. Lighting fires: (1) Lamp fire such as bulbs, including incandescent, iodine-tungsten lamp, and high pressure mercury lamps generate high temperature surfaces. The greater the power along with continuous service, the higher temperatures will be experienced. Thermal radiation from hot surfaces can be a source of spontaneous combustion if fuels and combustible materials are stored nearby. Fire Prevention bulbs should pay attention to make sure: no paper lamp door, or the use of paper, cloth lamp; likely to be hit in place, the lamps should have solid metal enclosures; they should not be closer than 30 cm from cloth, paper or clothing, and should be isolated from flammable materials. (2) Fluorescent fire: Ballasts can be the cause for such fires. Attention should be given to the installation of ventilation in order to provide cooling the fluorescent and to prevent leakage. Ballasts should be installed from the bottom up, not down. During installation, care should be given to prevent Asphalt seals from spilling and resulting in burning on the ballast. Ballasts may be installed with high temperature alarms that automatically cut off the power supply when temperature becomes excessive or smoke is detected.

2(i)(10) Firefighting Guidance 2(i)(10)(i) Types The types of firefighting are: • • • •

Structural firefighting is fighting fires involving buildings and other structures. Most city firefighting is structural firefighting. Structural firefighting is what most people think of when they think of what their local "fire department" does. Wildland firefighting is fighting forest fires, brush or bush fires, and fires in other undeveloped areas. Proximity firefighting is fighting fires in situations where the fire produces a very high level of heat, such as aircraft and some chemical fires. Proximity firefighting is not the same thing as structural firefighting and in some (but not all) cases takes place outdoors. Entry firefighting is a highly specialized form of firefighting involving the actual direct entry of firefighters into a fire with a very high level of heat. It is not the same thing as

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proximity firefighting, although it is used in many of the same situations (such as flammable liquid fires). Three elements necessary for a fire to burn: oxygen, fuel, and a source of heat. Remove any one of the three and the fire can no longer burn. All firefighting tactics are based on removing one or more of the three elements in the fire triangle. Fire fighting involves a range of methods and equipment for fighting fires, depending on the circumstances and availability. 2(i)(10)(ii) Firefighting Agents and Extinguishers Water: The standard method is to pour water onto the fire. This reduces the heat, hopefully to the point that the fire can no longer burn. However, water is not suitable for liquid fuel fires, because it is likely to spread the fuel and make the fire larger, nor for electrical fires, because of the risk of electric shock. Foam: Foam is put onto fires fuelled by liquid fuel. It works by preventing oxygen getting to the fire, but does not spread the fuel around. Powder: Powder is used on electrical fires, as it does not conduct electricity. Like foam, it works by cutting off the oxygen supply to the fire. Gas: Non-combustible gases are sometimes used in fire-suppression systems installed in buildings. They work by being heavier than air, thus displacing the oxygen. However, because the oxygen is displaced from the building, humans are unable to survive for long either, so gas systems are only used in special circumstances. Fire beaters and rakes: Fire beaters and rakes are low-tech ways to fight small fire in scrub. They work by spreading the fire out, thus reducing the concentration of heat, and by removing the source of fuel from the fire. Extinguishers: Fire extinguishers are canisters of water, foam, or powder which can be carried by one person to the fire. They are of limited capacity, but can be used to stop a fire before it becomes large. Vehicles: Various vehicles are used by fire fighters, including trucks which pump water from a nearby supply onto a fire, and tankers which carry water to the site of the fire when no local supply is available. Fire breaks: For fires in forested areas, bulldozers or other heavy equipment may be used to cut a clear path through the forest in front of an advancing fire, or such fire breaks may be permanently maintained in forested areas. Fire breaks provide an area with little fuel content, for the purpose of the fire stopping when it reaches the break. However, strong winds might carry sparks from the fire across the fire break to further forest on the other side. Even so, it may slow down the fire enough for fire crews to cope with the rest.

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Back-burning: Instead of constructing fire breaks, an area ahead of an advancing fire might be set alight and burnt in a controlled manner to remove the fuel from that area, thus impeding the advance of the main fire. For small fires, a fire extinguisher can be used. Remember P.A.S.S. (Pull - Aim - Squeeze Sweep). Fire extinguishers are rated for the types of fires they are effective against. Class A: ordinary flammable solids, such as wood and paper; Class B: flammable liquids, such as grease, oil, and gasoline; Class C: electrical fires. Class D: flammable metals. Fire extinguishers are divided into four categories, based on different types of fires. Each fire extinguisher also has a numerical rating that serves as a guide for the amount of fire the extinguisher can handle. The higher the number, the more fire-fighting power. The following is a quick guide to help choose the right type of extinguisher. • • •

•

Class A extinguishers are for ordinary combustible materials such as paper, wood, cardboard, and most plastics. The numerical rating on these types of extinguishers indicates the amount of water it holds and the amount of fire it can extinguish. Class B fires involve flammable or combustible liquids such as gasoline, kerosene, grease and oil. The numerical rating for class B extinguishers indicates the approximate number of square feet of fire it can extinguish. Class C fires involve electrical equipment, such as appliances, wiring, circuit breakers and outlets. Never use water to extinguish class C fires - the risk of electrical shock is far too great! Class C extinguishers do not have a numerical rating. The C classification means the extinguishing agent is non-conductive. Class D fire extinguishers are commonly found in a chemical laboratory. They are for fires that involve combustible metals, such as magnesium, titanium, potassium and sodium. These types of extinguishers also have no numerical rating, nor are they given a multi-purpose rating - they are designed for class D fires only.

Some fires may involve a combination of these classifications. •

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Water extinguishers or APW extinguishers (air-pressurized water) are suitable for class A fires only. Never use a water extinguisher on grease fires, electrical fires or class D fires - the flames will spread and make the fire bigger! Water extinguishers are filled with water and pressurized with oxygen. Again - water extinguishers can be very dangerous in the wrong type of situation. Only fight the fire if you're certain it contains ordinary combustible materials only. Dry chemical extinguishers come in a variety of types and are suitable for a combination of class A, B and C fires. These are filled with foam or powder and pressurized with nitrogen. – BC - This is the regular type of dry chemical extinguisher. It is filled with sodium bicarbonate or potassium bicarbonate. The BC variety leaves a mildly corrosive residue which must be cleaned Figure 6. Fire Extinghishers immediately to prevent any damage to materials.

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ABC - This is the multipurpose dry chemical extinguisher. The ABC type is filled with mono-ammonium phosphate, a yellow powder that leaves a sticky residue that may be damaging to electrical appliances such as a computer.

Dry chemical extinguishers have an advantage over CO2 extinguishers since they leave a nonflammable substance on the extinguished material, reducing the likelihood of re-ignition. •

Carbon Dioxide (CO2) extinguishers are used for class B and C fires. CO2 extinguishers contain carbon dioxide, a non-flammable gas, and are highly pressurized. The pressure is so great that it is not uncommon for bits of dry ice to shoot out the nozzle. They don't work very well on class A fires because they may not be able to displace enough oxygen to put the fire out, causing it to re-ignite.

CO2 extinguishers have an advantage over dry chemical extinguishers since they don't leave a harmful residue - a good choice for an electrical fire on a computer or other favorite electronic device such as a stereo or TV. These are only the common types of fire extinguishers. There are many others to choose from. Base your selection on the classification and the extinguisher's compatibility with the items you wish to protect. 2(i)(10)(iii) Vehicles The "fire truck" and "fire engine" are two different vehicles, and the terms should not be used interchangeably. In general, fire engines are outfitted to pump water at a fire. Trucks do not pump water and are outfitted with ladders and other equipment for use in ventilation of the building, rescue, and related activity. In many jurisdictions it is common to have a ladder (or truck) company and an engine company stationed together in the same firehouse. 2(i)(10)(iv) Firefighting Gear Basic firefighting gear includes: • Bunker gear - refers to the set of protective clothing worn by firefighters (Figures 8 and 9). This is made of a modern fire-resistant material such as Nomex, and has replaced the old rubber coat which was traditionally worn. Nomex is a registered trademark for flame resistant metaaramid material developed in the early 1960s by DuPont. The original use was for parachutes in the space program. A Nomex hood is a common piece of firefighting equipment. It is placed on the head on top of a firefighter's face mask. The hood Figure 7. Protective Clothing worn by protects the portions of the head not covered by Firemen the helmet and face mask from the intense heat of the fire.

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SCBA, or self-contained breathing apparatus, is worn in any IDLH (immediately dangerous to life or health) situation, which includes entry into burning buildings (where hot air and smoke inhalation present a danger) or any situation involving hazardous materials exposure. It consists of a breathing mask and a tank of air worn on the back. Helmet, boots, gloves. Tools: traditional hand tools such as the pike, halligan, pulaski, axe, hydrant wrench; power tools such as saws. Hoses and nozzles. Other equipment.

"Two in, two out" refers to the rule that firefighters never enter a building or other IDLH situation alone but go in Figure 8. Protective Clothing and as a pair. Two go in and two come out; also, the two in Equipment used by Firemen can refer to the two who enter the building while a backup team of two remains outside the building ready to enter if needed. To minimize the risk of electrocution, electrical shock, and electricity-related burns while fighting wildland fires, NIOSH recommends that fire departments and fire fighters take the following precautions [IFSTA 1998a,b; NWCG 1998; NFPA 1997; 29 CFR* 1910.332(b); 29 CFR 1910.335(b); Brunacini 1985]: Fire departments should do the following: • • •

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Keep fire fighters a minimum distance away from downed power lines until the line is de-energized. This minimum distance should equal the span between two poles. Ensure that the Incident Commander conveys strategic decisions related to power line location to all suppression crews on the fireground and continually reevaluates fire conditions. Establish, implement, and enforce standard operating procedures (SOPs) that address the safety of fire fighters when they work near downed power lines or energized electrical equipment. For example, assign one of the fireground personnel to serve as a spotter to ensure that the location of the downed line is communicated to all fireground personnel. Do not apply solid-stream water applications on or around energized, downed power lines or equipment. Ensure that protective shields, barriers, or alerting techniques are used to protect fire fighters from electrical hazards and energized areas. For example, rope off the energized area. Train fire fighters in safety-related work practices when working around electrical energy. For example, treat all downed power lines as energized and make fire fighters aware of hazards related to ground gradients.

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Ensure that fire fighters are equipped with the proper personal protective equipment (Nomex® clothing compliant with NFPA standard 1500 [NFPA 1997], leather boots, leather gloves, etc.) and that it is maintained in good condition. Ensure that rubber gloves and dielectric overshoes and tools (insulated sticks and cable cutters) for handling energized equipment are used by properly trained and qualified personnel.

Fire fighters should do the following: • • •

Assume all power lines are energized and call the power provider to de-energize the line(s). Wear appropriate personal protective equipment for the task at hand—Nomex® clothing compliant with NFPA standard 1500, rubber gloves, and dielectric overshoes and tools (insulated sticks and cable cutters). Do not stand or work in areas of dense smoke. Dense smoke can obscure energized electrical lines or equipment and can become charged and conduct electrical current.

2(i)(11) Specialized Rescue Procedures There are many common types of rescues such as building search, victim removal, and extrication from motor vehicles. On the other side there are certain specialized rescues such as water rescues, ice rescues, structural collapse rescues, and elevator/escalator rescues. These specialized rescues are generally low volume calls, depending on coverage area, and thus should be trained for fire fighters to better asses the situation. Structural collapse, while not a common incident, may occur for any number of reasons: weakening from age or fire, environmental causes (earthquake, tornado, hurricane, flooding, rain, or snow buildup on roofs), or an explosion (accidental or intentional). Structural collapses can create numerous voids where victims could be trapped. When arriving on scene the number of potential victims should be acquired. Certain hazards to look for in a structural collapse are a secondary collapse, live electrical wires, and gas leaks. The electricity and gas should be shut-off. Structural collapses come in three different types: pancake collapse, lean-to collapse, and v-type collapse. • • •

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A pancake collapse is characterized by both supporting walls failing or from the anchoring system failing and the supported roof or upper floor falling parallel to the floor below. Small voids where victims can be found are created by debris. A lean-to collapse occurs when one only one side of the supporting walls or floor anchoring system fails. One side of the collapsed roof is attached to the remaining wall or anchoring system. The lean-to collapse creates a significant void near the remaining wall. A v-type collapse can happen when there is a large load in the center of the floor or roof above. The roof may be overloaded from a buildup of snow and/or have been weakened by fire, rot, termites, and improper removal of support beams. Both sides of the supporting wall are still standing but the center of the floor or roof above is compromised and thus collapsed in the center. The v-type collapse usually leaves a void on each side of the supporting walls.

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Knowing where the voids are can help a fire fighter locate survivors of the structural collapse. After the firefighter has identified the type of collapse and where the voids may be they need to make a safe entranceway. The firefighter needs to have a basic knowledge of cribbing, shoring, and tunneling, all of which are useful in collapse operations. Cribbing is the use of various sizes of lumber arranged in systematic stacks to support an unstable load. Shoring is the use of wood to support and/or strengthen weakened structures such as roofs, floors, and walls. This avoids a secondary collapse during rescue. Tunneling could be necessary to reach survivors if there is no way other way to reach the victim. When tunneling there should be a set destination and a good indication that there is a victim in that void. 2(i)(12) First Responder to Electrical Fire Incidents This information is essential for anyone who might encounter emergency situations where energized electrical equipment creates a hazard. The language is intentionally non-technical in an effort to provide easily understandable information for those without an in-depth knowledge of electricity. Because of the wide variety of emergency situations first responders (i.e., law enforcement officers, fire fighters, ambulance attendants, etc.) might encounter, it is not possible to cover every situation. •

•

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•

You must always maintain proper respect for downed wires even though some may appear harmless. Electrical equipment requires the same respect, awareness and caution you would accord a firearm – always "consider it loaded." In situations where no emergency exists and human life is not in any immediate danger, wait for the local utility personnel to secure the area; they have the knowledge and equipment to complete the job safely. Law enforcement officers, fire fighters or ambulance attendants are usually first on the scene when overhead wires are down – usually as a result of storms, damaged utility poles or fallen branches. They need to be aware of the hazards and procedures involved in dealing with emergencies resulting from fallen energized wires. Electricity seeks the easiest path to ground itself and does not "care" how it gets there. If you or your equipment creates that path, you will be placing yourself (and possibly others) in a life threatening situation. In some situations fallen wires snap and twist, sending out lethal sparks as they strike the ground. At other times the wires lie quietly; producing no sparks or warning signals – as quiet as a rattlesnake and potentially as dangerous. The first rule is to consider any fallen or broken wire extremely dangerous and not to approach within eight feet of it. Next, notify the local utility and have trained personnel sent to the scene. Have an ambulance or rescue unit dispatched if necessary. Remember, do not attempt to handle wires yourself unless you are properly trained and equipped. Set out flares and halt or reroute traffic. Keep all spectators a safe distance (at least 30.5 meters) from the scene. Electric power emergencies often occur when it is raining; wet ground increases the hazard. After dark, light the scene as well as you can. Direct your spotlight on the broken or fallen wires. Remember that metal or cable guard-rails, steel wire fences and telephone lines may be energized by a fallen wire and may carry the current a mile or more from the point of contact. An ice storm, windstorm, tornado, forest fire or flood may bring down power lines by the hundreds. Under those circumstances electric companies customarily borrow skilled II-265

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professionals from one another to augment their own work forces. First Responders have their own jobs to perform at such times – usually as part of a task force – which lessens the need for individual decision making. But every first responder should be prepared for when he or she faces an electric power emergency alone and must make decisions about people, power and the hazards involved. Remember that electricity from a power line (like lightening from a thundercloud) seeks to reach the ground, so it is imperative when working with fallen wires not to let yourself or others create a circuit between a wire and the ground. In a typical power emergency a car strikes a utility pole and a snapped power line falls on it. Advise the car's occupants they should stay in the car. Call the local power company, but remember: Do not come in contact with either the car or its occupants. If the car catches fire, instruct the occupants to leap, not step, from the car. To step out would put them in the circuit between the wire, the energized car and the ground – with deadly results. If fire fighters are on the scene, they may be best able to handle the situation; most full-time fire fighters are trained to deal with electric power emergencies and will have the proper equipment to do so. If you must extinguish a car fire without the aid of fire fighters, use only dry chemical or CO2 extinguishers. If the car's occupants are injured and cannot leap to safety, you may be able to use your vehicle to push them out of contact with the wire. If you do this, it is critical to look around the vehicle before leaving your car – there may be another fallen wire behind you or a wire hooked to your bumper. If there is (or you suspect there is), leap from your vehicle. Once a victim has been removed from the electric hazard, immediately check vital signs. If the victim has no pulse and is not breathing, begin cardio-pulmonary resuscitation immediately (and any other appropriate first aid treatment) until he or she is placed in the ambulance. In any rescue attempt it is essential that you protect yourself – it is a truism that dead heroes rescue no one. Do not, under any circumstance, rely on rubber boots, raincoats, rubber gloves or ordinary wire cutters for protection. Above all, do not touch (or allow your clothing to touch) a wire, a victim, or a vehicle that is possibly energized.

2(i)(13) Evacuation Planning Each facility should have a written plan for the orderly evacuation of each building at a facility. The plan should establish the necessary procedures for fire emergencies, bomb threats, etc. Each employee should be familiar with the plan. The following are recommended essential elements to include in the plan. 2(i)(13)(i) Designated Roles and Responsibilities There should be a Building Coordinator for each building who is the designated Responsible Individual. The Building Coordinator is responsible for seeing that the plan is implemented and will appoint an adequate number of Floor Marshals, assure everyone is familiar with this plan and act as a liaison with the Health and Safety Officer (HSO) and First Responders such as the Fire Department. For the Floor Marshals, at least one individual per floor should be designated and there should be designated back-ups. Floor Marshals will assist in the implementation of the plan by knowing

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and communicating evacuation routes to occupants during emergency evacuation and report the status of the evacuation to the Building Coordinator. 2(i)(13)(ii) Preparation & Planning for Emergencies Pre-planning for emergencies is a crucial element of the plan. The following steps should be taken in planning for emergency evacuation of each building: 1. All exits are labeled and operable. 2. Evacuation route diagrams have been approved by the HSO or Safety Division and are posted on all floors and at all exits, elevator lobbies, training/conference rooms and major building junctions. 3. Occupants do not block exits, hoses, extinguishers, corridors or stairs by storage or rearrangement of furniture or equipment. Good housekeeping is everyone's responsibility. 4. All Floor Marshals have been trained in their specific duties and all building occupants have been instructed in what to do in case of an emergency evacuation. 5. Fire evacuation drills are held at least annually in this building and are critiqued and documented. Prior to holding a fire evacuation drill where the alarm is to be triggered, the Electric Shop and the Fire Marshal are notified. 6. Appendix A contains instructions that are posted and/or used in instructing students and visitors using this building's facilities. 2(i)(13)(iii) Evacuation Procedure When a fire is discovered: 1. Anyone who receives information or observes an emergency situation should immediately call a central designated number. The Plan should identify the Emergency Number to call, which for most offices can be the Fire Department, Police Department, or Civil Defense. 2. In the incident building, occupants will be notified of emergencies by a notification system such as: fire alarm, paging system, and/or word of mouth. Occupants will: 1. Know at least two exits from the building. 2. Be familiar with the evacuation routes posted on the diagram on your floor. 3. To report a fire or emergency, call the Emergency Number. Give your name, room number and the floor that locates the fire. State exactly what is burning, or what is smoking or what smells like a fire to you. Then notify the Building Coordinator (or other designated person) and activate the building notification system. 4. When notified to evacuate, do so in a calm and orderly fashion: a. Walk, don't run. b. Keep conversation level down. c. Take your valuables and outer garments. d. Close all doors behind you. e. Use the stairs, not the elevators. f. Assist others in need of assistance. II-267

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5. Go to the designated assembly area or as instructed during the notification. Upon exiting the building, move at least 45.7 meters from the building to allow others to also safely exit the building. (specify designated assembly areas or indicate areas on evacuation diagram). 2(i)(13)(iv) General During evacuation Floor Marshals should assure that every person on his/her floor has been notified and that evacuation routes are clear. If possible, the Floor Marshal - will check that all doors are closed and be the last one out. Upon leaving the floor, the Floor Marshal will report the status of the floor evacuation to the Building Coordinator. Persons with Disabilities (mobility, hearing, sight): Each individual who requires assistance toevacuate is responsible for pre-arranging with someone else in their immediate work area to assist them. Anyone knowing of a person with a disability or injury who was not able to evacuate will report this immediately to a Floor Marshal, the Building Coordinator or the Incident Commander. The following are general evacuation instructions to include in Plan: 1. Know at least two exits from the building. 2. Be familiar with the evacuation routes posted on the diagram on your floor. 3. To report a fire or emergency, call a central Emergency Number designated in the Plan. Give your name, room number and the floor that locates the fire. State exactly what is burning, or what is smoking or what smells like a fire to you. Then notify the Building Manager or other designated person and activate the building notification system. 4. When notified to evacuate, do so in a calm and orderly fashion: a. Walk, don't run. b. Keep conversation level down. c. Take your valuables and outer garments. d. Close all doors behind you. e. Use the stairs, not the elevators. f. Assist others in need of assistance. 5. Go to the designated assembly area or as instructed during the notification. If exiting the building, move at least 45.7 meters from the building to allow others to also safely exit the building. 6. Persons with disabilities that may impair mobility should establish a buddy system to help ensure that any needed assistance will be available to them in an emergency. 2(i)(13)(v) Template for Emergency Evacuation Plan The following are general guidelines for implementation: 1. Assignment of Responsibility - Administrative responsibility for evacuation of each building must be clearly defined. The HSO shall designate an individual with a thorough understanding and appropriate authority as the Building Coordinator under the plan. The Building Coordinator shall appoint Floor Marshals as appropriate and ensure that they are adequately instructed in their duties and responsibilities. There must be adequate II-268

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alternates to assume responsibilities in the absence of the Building Coordinator or Floor Marshals. These designations should also be made in the pre-planning stage. Coordination - In buildings that are under the control of more than one manager or HSO, there should be one evacuation plan for that building that has been coordinated with all key persons. Notification - The Building Coordinator must assure that building occupants know who to call in case of an emergency and the proper sequence of notification. If it is a fire emergency, call a designated three digit number (in the United States 911 for example), then notify the Building Coordinator and activate the building notification system. Similar emergency incidents may be covered under the same Plan. If it is a tornado, the Building Coordinator or other designated person will notify occupants through the Floor Marshal of safe places of haven. If it is a bomb threat, call a centralized Emergency Notification Number identified in the Plan, then notify the Building Coordinator, but do not activate the building notification system. Responsible Parties will review the specific circumstances and mandate evacuation when deemed necessary or will otherwise advise Management when evacuation is not necessary. Occupants must be aware of who to notify in the event the Building Coordinator is absent. The Building Coordinator must assure that there is an effective method to notify occupants of an emergency. Notification may be by means of an alarm system, public address system, telephone fan out system or oral communication, although this last method is not advisable for work areas with ten or more persons. Preparation and Planning - Proper preparation and planning for emergencies is essential in order for evacuation to be effective and efficient. Emergency route diagrams can be produced using the building "key plans". These should be made accessible to all employees. Building/room diagrams should also be made available through the Facilities Management Information System (FMIS). Use the key plan to highlight the main corridor exit ways and stairways and to identify the exits. You can also use this diagram to indicate where fire extinguisher and fire fighting equipment are located by using color coding or a symbol. The diagram can also be used to indicate designated assembly areas. Post the diagrams at: elevator lobbies, junctions in buildings where directions are routinely posted, information bulletin boards, training/conference rooms, or other strategic locations throughout the building. All emergency route diagrams must be reviewed the Fire Marshall and the HSO. Make sure all exits are labeled, operable and not blocked and there is proper illumination of pathways and exit signs. Floor Marshals should be fully familiar with the building evacuation plan and their role. Make sure there are alternates to cover during absences. Decide on a designated meeting place outside the building where Floor Marshals can quickly report to the Building Coordinator and where occupants can be accounted for. Communicate the program to all staff in each building. Fire Evacuation Drills - All building occupants must be familiar with what they should do during an evacuation. The most effective method of familiarizing them is to hold a fire drill at least annually. Holding a fire drill has other advantages as well; it will provide you with an opportunity to evaluate your notification and evacuation procedures and it will give you an opportunity to test your fire alarm system and make occupants aware of the sound.

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Steps In Conducting a Fire Drill: a. If you have an alarm system you must first contact the Electric Shop to make the appropriate arrangements. b. Contact the Fire Marshal before holding your drill so that a representative can be on site to assist in critiquing the evacuation. c. Although the fire drills should be unannounced, you may need to give advanced notice to key personnel in your building. 2(i)(14) Bibliography Cheremisinoff, N. P., Handbook of Industrial Toxicology and Hazardous Materials, Marcel Dekker Publishers, New York, New York, 1999.

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SEC. 2(j) ELECTRIC SHOCK AND LOCKOUT/TAGOUT CONTENTS 2(j)(1) Introduction ................................................................................................................... 273 2(j)(2) Fuses ............................................................................................................................... 273 2(j)(3) GFCIs ............................................................................................................................. 273 2(j)(4) Electrical Shock ............................................................................................................. 274 2(j)(5) Feedback Electrical Energy.......................................................................................... 276 2(j)(6) Universal Precautions ................................................................................................... 276 2(j)(7) Training Programs........................................................................................................ 276 2(j)(8) Protective Equipment and Work Practices ................................................................ 276 2(j)(9) Detection of Low Voltage.............................................................................................. 277 2(j)(10) Lockout/Tagout ........................................................................................................... 277 2(j)(11) Lockout Devices........................................................................................................... 279 2(j)(12) Specific Procedures for Logout/Tagout..................................................................... 279 2(j)(13) Bibliography ................................................................................................................ 281

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2(j)(1) Introduction Several occupational safety and health investigations have documented a number of fatalities whose circumstances suggest that the victims were unaware of the electrocution hazard from feedback electrical energy in power lines that were assumed to be de-energized. Occupational electrocutions from all causes continue to be a serious problem and take a very large toll on the workforce. Safety laws are established to help provide safe working areas for electricians. Individuals can work safely on electrical equipment with today's safeguards and recommended work practices. In addition, an understanding of the principles of electricity is gained. It is good practice to always ask supervisors when in doubt about a procedure. Additionally, reporting any unsafe conditions, equipment, or work practices as soon as possible can help reduce the number of electrical shock accidents and fatalities. 2(j)(2) Fuses25 Confirm that the switch for the circuit is open or disconnected before removing any fuse from a circuit. When removing fuses, use an approved fuse puller and break contact on the hot side of the circuit first. When replacing fuses, first install the fuse into the load side of the fuse clip, then into the line side. 2(j)(3) GFCIs26 A groundfault circuit interrupter (GFCI) is an electrical device which protects personnel by detecting potentially hazardous ground faults and immediately disconnecting power from the circuit. Any current over 8 mA is considered potentially dangerous depending on the path the current takes, the amount of time exposed to the shock, as well as the physical condition of the person receiving the shock. GFCls should be installed in such places as dwellings, hotels, motels, construction sites, marinas, receptacles near swimming pools and hot tubs, underwater lighting, fountains, and other areas in which a person may experience a ground fault. A GFCI compares the amount of current in the ungrounded (hot) conductor with the amount of current in the neutral conductor (Figure 10). If the current in the neutral conductor becomes less than the current in the hot conductor, a ground fault condition exists. The missing current is returned to the source by some path other than the intended path (fault current). A fault current as low as 4 mA to 6 mA activates the GFCI and interrupts the circuit. Once activated, the fault condition is cleared and the GFCI manually resets before power may be restored to the circuit.

25 26

Electricians Toolbox Etc., http://www.elec-toolbox.com/Safety/safety.htm Ibid.

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Figure 9. A GFCI compares the amount of current in the ungrounded (hot) conductor with the amount of current in the neutral conductor.

GFCI protection may be installed at different locations within a circuit. Direct-wired GFCI receptacles provide a ground fault protection at the point of installation. GFCI receptacles may also be connected to provide GFCI protection at all other receptacles installed downstream on the same circuit. GFCI CBs, when installed in a load center or panelboard, provide GFCI protection and conventional circuit overcurrent protection for all branch-circuit components connected to the CB. Plug-in GFCls provide ground fault protection for devices plugged into them. Plug-in devices are generally utilized by personnel working with power tools in an area that does not include GFCI receptacles. 2(j)(4) Electrical Shock27 Most fatal electrical shocks happen to people who are actually knowledgeable regarding electrical shock safety precautions. A majority of the electrical shock accidents occur when an employee in a rush disregards safety precautions that they know should be followed. The following are some electromedical facts intended to make employees think twice before taking chances. It's not the voltage but the current that kills. People have been killed by 100 volts AC in the home and with as little as 42 volts DC. The real measure of a shock's intensity lies in the amount of current (in milliamperes) forced through the body. Any electrical device used on a house wiring circuit can, under certain conditions, transmit a fatal amount of current. Currents between 100 and 200 milliamperes (0.1 ampere and 0.2 ampere) are fatal. Anything in the neighborhood of 10 milliamperes (0.01) is capable of producing painful to severe shock. 27

Electricians Toolbox Etc., http://www.elec-toolbox.com/Safety/safety.htm.

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Current values and their effects are summarized in Table 22 below. Table 22. Current values and their effects

Readings < than 1 mA 1 mA to 8 mA

Effects Causes no sensation Sensation of shock, not painful. Safe Current Values Individual can let go at will since muscular control is not lost 8 mA to 15 mA Painful shock; individual can let go at will since muscular control is not lost. 15 mA to 20 mA Painful shock; control of adjacent muscles lost; victim can not let go. 50 mA to 100mA Ventricular fibrillation – a heart condition Unsafe Current Values that can result in death is possible. 100 mA to 200 mA Ventricular fibrillation occurs. > than 200 mA Severe burns, severe muscular contraction, so severe that chest muscles clamp the heart and stop it for the duration of the shock. Ref: Electricians Toolbox Etc., http://www.elec-toolbox.com/Safety/safety.htm The severity of the shock increases as the current increases. Below 20 milliamperes, breathing becomes labored, and it can cease completely even at values below 75 milliamperes. As the current approaches 100 milliamperes ventricular fibrillation occurs. This is an uncoordinated twitching of the walls of the heart's ventricles. Since you don't know how much current went through the body, it is necessary to perform artificial respiration to try to get the person breathing again. If the heart is not beating, cardio pulmonary resuscitation (CPR) is necessary. Electrical shock occurs when a person comes in contact with two conductors of a circuit or when the body becomes part of the electrical circuit. In either instance, a severe shock can cause the heart and lungs to stop functioning. Additionally, severe burns may occur where current enters and exits the body. Prevention is the best medicine for electrical shock. Employees should respect all voltages and possess the knowledge of the principles of electricity. It is important to always follow safe work procedures. Do not take unnecessary chances. All electricians should be encouraged to take a basic course in CPR so they can aid a coworker in emergency situations. Portable electric tools should always be well maintained and in safe operating condition. Make sure there is a third wire on the plug for grounding in case of shorts. The fault current should flow through the third wire to ground instead of through the operator's body to ground if electric power tools are grounded and if an insulation breakdown occurs.

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2(j)(5) Feedback Electrical Energy28 The potential for electrocution due to feedback electrical energy should never be underestimated. Workers may not be aware of the extreme hazard of electrocution and electrical injuries presented by feedback energy. The problem of feedback electrical energy in electrical transmission and distribution systems is always present and diligent efforts should be applied to safeguard against it. "Fuzzing" a line is a standard practice to test for the presence of high voltage in power lines. "Fuzzing" is accomplished by bringing a metallic object, such as a pair of lineman's pliers, close to a power line while watching for an arc and listening for a buzzing sound. This method does not reliably detect low voltages and should not be used as the only test for electrical energy in power lines. Once fuzzing has determined that high voltage is not present, low voltage testing equipment, such as a glowing neon light or a light-emitting diode, should be used to determine whether low voltage is present. 2(j)(6) Universal Precautions29 • •

Exercise extreme caution when working on or in the vicinity of unverified de-energized power lines. All persons performing this work should treat all power lines as "hot" unless they positively know these lines are properly de-energized and grounded. “Fuzzing," although an accepted practice to check for high voltage in power lines, is not a reliable test method. "Fuzzing" should only be attempted after power lines have been de-energized and properly grounded. The person performing the work should personally ground all lines on both sides of the work area unless he or she is wearing the proper protective equipment.

2(j)(7) Training Programs30 • •

Training programs for linemen should emphasize proper procedures for working with electrical transmission and distribution systems and their associated hazards. Training programs for linemen should include basic electrical theory that addresses electrical distribution systems and the identification, evaluation, and control of the hazards associated with these systems. Because the danger of feedback energy is always present, an improved method of de-energizing these systems should be stressed.

2(j)(8) Protective Equipment and Work Practices31 • • •

28

Power lines should not be repaired or otherwise accessed without adequate personal protective equipment unless the worker personally verifies that the line is de-energized and properly grounded. Workers must be specifically instructed to wear proper protective equipment, such as gloves and sleeves, required for the task to be performed. Linemen must be instructed to treat all power lines as energized unless they personally de-energize them by establishing a visible open point between the load and supply sides

The National Institute for Occupational Safety and Health, Preventing Electrocutions by Undetected Feedback Electrical Energy Present in Power Lines, Publication No. 88-104, December 1987. 29 Ibid. 30 Ibid. 31 Ibid.

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of the line to be repaired, by opening a fused disconnect, by opening a fused switch, or by removing a tap jumper if the load permits. Workers must verify that the power lines have been de-energized. Workers must provide proper grounding for the lines. Unless a power line is effectively grounded on both sides of a work area, it must be considered energized even though the line has been de-energized. Lines must be grounded to the system neutral. Grounds must be attached to the system neutral first and removed from the system neutral last. If work is being performed on a multiphase system, grounds must be placed on all lines. Lines should be grounded in sight of the working area and work should be performed between the grounds whenever possible. If work is to be performed out of sight of the point where the line has been de-energized, an additional ground should be placed on all lines on the source side of the work area.

2(j)(9) Detection of Low Voltage32 • •

Appropriate safety and protective equipment should be provided to all persons working on or in the vicinity of power lines. All persons should also be trained in procedures that address all magnitudes of voltages. to which they may be exposed Procedures should be established to perform a dual voltage check on the grounded load and supply sides of the open circuit. Once the "fuzzing" method has determined that high voltage is not present, low voltage testing equipment, such as a glowing neon light or a light-emitting diode, should be used to determine if lower voltage is present.

2(j)(10) Lockout/Tagout33 Electrical power must be removed when electrical equipment is inspected, serviced, or repaired. To ensure the safety of personnel working with the equipment, power is removed and the equipment must be locked out and tagged out. Equipment should be locked out and tagged out before any preventive maintenance or servicing is performed (Figure 11). Lockout is the process of removing the source of electrical power and installing a lock which prevents the power from being turned ON. Tagout is the process of placing a danger tag on the source of electrical power which indicates that the equipment may not be operated until the danger tag is removed. A danger tag has the same importance and purpose as a lock and is used alone only when a lock does not fit the disconnect device. The danger tag shall be attached at the disconnect device with a tag tie or equivalent and shall have space for the worker's name, craft, and other required information. A danger tag must withstand the elements and expected atmosphere for as long as the tag remains in place. A lockout/tagout should be used when: •

Servicing electrical equipment that does not require power to be ON to perform the service;

32

The National Institute for Occupational Safety and Health, Preventing Electrocutions by Undetected Feedback Electrical Energy Present in Power Lines, Publication No. 88-104, December 1987. 33 Electricians Toolbox Etc., http://www.elec-toolbox.com/Safety/safety.htm.

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Removing or bypassing a machine guard or other safety device. The possibility exists of being injured or caught in moving machinery; and

Figure 10. Equipment must be locked out and tagged out before preventive maintenance or servicing is performed.

•

Clearing jammed equipment. The danger exists of being injured if equipment power is turned ON.

An approved procedure should be developed, implemented and followed when applying a lockout/tagout. Lockouts and tagouts are attached only after the equipment is turned OFF and tested to ensure that power is OFF. The lockout/tagout procedure is required for the safety of workers due to modern equipment hazards. An example of a standard procedure for equipment lockout/tagout is: 1. 2. 3. 4. 5. 6.

Prepare for machinery shutdown; Machinery or equipment shutdown; Machinery or equipment isolation; Lockout or tagout application; Release of stored energy; and Verification of isolation.

A lockout/tagout should only be removed by the person that installed it, except in an emergency. In an emergency, the lockout/tagout may be removed only by authorized personnel. The authorized personnel shall follow approved procedures. The following lockout and tagout procedures and steps can effectively reduce the number of electrocutions in the workplace: • • • • • •

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Use a lockout and tagout whenever possible; Use a tagout when a lockout is impractical. A tagout is used alone only when a lock does not fit the disconnect device; Utilize a multiple lockout when individual employee lockout of equipment is impractical; Notify all employees affected before using a lockout/tagout; Remove all primary and secondary power sources; and Measure for voltage using a voltmeter to ensure that power is OFF.

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2(j)(11) Lockout Devices34 Lockout devices are lightweight enclosures that allow the lockout of standard control devices. Lockout devices are available in various shapes and sizes that allow for the lockout of ball valves, gate valves, and electrical equipment such as plugs, disconnects, etc. Lockout devices resist chemicals, cracking, abrasion, and temperature changes. They are available in colors to match ANSI pipe colors. Lockout devices are sized to fit standard industry control device sizes. Locks used to lock out a device may be color coded and individually keyed. The locks are rust-resistant and are available with various size shackles. Danger tags provide additional lockout and warning information. Various danger tags are available. Danger tags may include warnings such as "Do Not Start," "Do Not Operate," or may provide space to enter worker, date, and lockout reason information. Tag ties must be strong enough to prevent accidental removal and must be self-locking and nonreusable. 2(j)(12) Specific Procedures for Logout/Tagout 1. Preparation for Lockout/Tagout35 • Prepare and conduct a survey to locate and identify all isolating devices to be certain which switches, valves, or other energy isolating devices apply to the equipment to be locked or tagged out. It is possible that more than one energy source (electrical, mechanical, stored energy, or others) may be involved. 2. Sequence of Lockout or Tagout System Procedure36 • Notify affected employees that a lockout or tagout system is going to be utilized the reason for using the system. • The authorized employee shall know the type and magnitude of energy that the machine or equipment utilizes and shall understand the potential dangers and hazards. • If the machine or equipment is operating, shut it down by the normal stopping procedure (depress stop button, open toggle switch, etc.). • Operate the switch, valve, or other energy isolating devices in order to isolate the equipment from its energy sources. • Stored energy must be dissipated or restrained by methods such as repositioning, blocking, bleeding down, etc. • Lockout/tagout the energy isolating devices with assigned individual locks and/or tags. • After ensuring that no personnel are exposed, and to serve as a check on having disconnected the energy sources, operate the push button or other normal operating controls to make sure the equipment will not operate. CAUTION: Always return operating controls to neutral or off position after the test. • The equipment is now locked out or tagged out.

34

Electricians Toolbox Etc., http://www.elec-toolbox.com/Safety/safety.htm. North Carolina State University, Environmental Health and Public Safety, http://www.ncsu.edu/ehs/www99/right/handsMan/workplace/lockout.html 36 Ibid. 35

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3. Restoring Machines or Equipment to Normal Operations37 • Once the servicing and/or maintenance is complete and the equipment is ready for normal production operations, safeguard the area around the machines or equipment to ensure that no one is exposed. • Lockout or tagout devices should only be removed after all tools have been removed from the machine or equipment, guards have been reinstalled, and employees are in the clear. Operate the energy isolating devices to restore energy to the machine or equipment. 4. Procedure Involving More Than One Person38 If more than one individual is required to lockout or tagout equipment, each shall place his/her own personal lockout/tagout device on the energy isolating devices. A multiple lockout or tagout device may be used when an energy isolating device cannot accept multiple locks or tags. If lockout is used, a single lock may be used to lockout the machine or equipment with the key being placed in a lockout box or cabinet which allows the use of multiple locks to secure it. Each employee will then use his/her own lock to secure the box or cabinet. As each person no longer needs to maintain his/her lockout protection, that person will remove his/her lock from the box or cabinet. 5. Temporary Removal of Lockout/Tagout Devices39 In situations where lockout/tagout devices must be temporarily removed from the energy isolating device and the machine or equipment energized to test or position the machine, equipment or component thereof, the following sequence of actions should be followed: 1. 2. 3. 4. 5.

Remove non-essential items and ensure that machine or equipment components are operationally intact. Notify affected employees that lockout/tagout devices have been removed and ensure that all employees have been safely positioned or removed from the area. Have employees who applied the lockout/tagout devices remove the lockout/tagout devices. 6. Energize and proceed with testing or positioning. 7. De-energize all systems and reapply energy control measures. 6. Maintenance Requiring Undisrupted Energy Supply40 Where maintenance, repairing, cleaning, servicing, adjusting, or setting up operations cannot be accomplished with the prime mover or energy source disconnected, such operations may only be performed under the following conditions: •

37

The operating station (e.g. external control panel) where the machine may be activated must at all times be under the control of a qualified operator.

North Carolina State University, Environmental Health and Public Safety, http://www.ncsu.edu/ehs/www99/right/handsMan/workplace/lockout.html. 38 Ibid. 39 Sonoma State University, Environmental Health & Safety, http://www.sonoma.edu/ehs/esp/LOTOp.shtml. 40 Sonoma State University, Environmental Health & Safety, http://www.sonoma.edu/ehs/esp/LOTOp.shtml.

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All participants must be in clear view of the operator or in positive communication with each other. All participants must be beyond the reach of machine elements which may move rapidly and present a hazard. Where machine configuration or size requires that the operator leave the control station to install tools, and where there are machine elements which may move rapidly, if activated, such elements must be separately locked out. During repair procedures where mechanical components are being adjusted or replaced, the machine shall be de-energized or disconnected from its power source.

2(j)(13) Bibliography Electrical Safety-Related Work Practices Program, 29 Code of Federal Regulations 1910.331335, Washington, DC: U.S. Government Printing Office, Office of the Federal Register, 1985. Electricians Toolbox Etc., http://www.elec-toolbox.com/Safety/safety.htm. Nigerian Electrical Safety Code. C2-1984, Section 42-420, New York, NY: American Nigerian Standards Institute, 1984. Nigerian Institute for Occupational Safety and Health, Preventing Electrocutions by Undetected Feedback Electrical Energy Present in Power Lines, Publication No. 88-104, December 1987. Occupational Safety and Health Act of 1984, Fatalgram: Reports of OSHA Fatality/Catastrophe Investigations, Washington, DC: U.S. Department of Labor, Occupational Safety and Health, 1984. North Carolina State University, Environmental Health and Public Safety, http://www.ncsu.edu/ehs/www99/right/handsMan/workplace/lockout.html. Occupational Safety and Health Administration, An Illustrated Guide to Electrical Safety, U.S. Department of Labor, 1983. Sonoma State University, Environmental Health & Safety, http://www.sonoma.edu/ehs/esp/LOTOp.shtml.

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SEC. 2(k) HAND TOOLS AND WORKSHOP MACHINES CONTENTS 2(k)(1) Introduction ..............................................................................................................II-285 2(k)(2) What Are the Hazards of Hand Tools? ..................................................................II-285 2(k)(3) What Are the Dangers of Power Tools?.................................................................II-286 2(k)(4) Guards .......................................................................................................................II-286 2(k)(5) Operating Controls and Switches ...........................................................................II-287 2(k)(6) Electric Tools ............................................................................................................II-287 2(k)(7) Portable Abrasive Wheel Tools...............................................................................II-288 2(k)(8) Pneumatic Tools .......................................................................................................II-289 2(k)(9) Liquid Fuel Tools......................................................................................................II-290 2(k)(10) Powder-Actuated Tools..........................................................................................II-290 2(k)(11) Hydraulic Power Tools ..........................................................................................II-291 2(k)(12) General Requirements of Safety in Workshops Policy.......................................II-292 2(k)(13) Machinery Installation...........................................................................................II-293 2(k)(14) Machine Controls ...................................................................................................II-293 2(k)(15) Machine Guards .....................................................................................................II-293 2(k)(16) Service Installations ...............................................................................................II-293 2(k)(17) Grinding and Polishing Machines.........................................................................II-294 2(k)(18) Milling Machines ....................................................................................................II-294 2(k)(19) Metal-Cutting Guillotines......................................................................................II-295 2(k)(20) General Considerations .........................................................................................II-295 2(k)(21) Solvent Degreasing .................................................................................................II-296 2(k)(22) Bibliography ...........................................................................................................II-296

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2(k)(1) Introduction Employees should be trained in the proper use of all tools. Workers should be able to recognize the hazards associated with the different types of tools and the safety precautions necessary. Five basic safety rules can help prevent hazards associated with the use of hand and power tools: • • • • •

Keep all tools in good condition with regular maintenance; Use the right tool for the job; Examine each tool for damage before use and do not use damaged tools; Operate tools according to the manufacturers' instructions; and Provide and use properly the right personal protective equipment.

Employees and employers should work together to establish safe working procedures. If a hazardous situation is encountered, it should be brought immediately to the attention of the proper individual for hazard abatement. 2(k)(2) What Are the Hazards of Hand Tools?41 Employees should be trained in the proper use and handling of tools and equipment. The greatest hazards posed by hand tools result from misuse and improper maintenance. Some examples include: • • • • •

Using a chisel as a screwdriver, the tip of the chisel may break and fly off, hitting the user or other employees. If a wooden handle on a tool is loose, splintered, or cracked, the head of the tool may fly off and strike the user or other employees. If the jaws of a wrench are sprung, the wrench might slip. If impact tools such as chisels, wedges, or drift pins have mushroomed heads, the heads might shatter on impact, sending sharp fragments flying toward the user or other employees. When working in close proximity, employees should target saw blades, knives, or other tools away from away aisle areas and other employees. Knives and scissors must be sharp; dull tools can cause more hazards than sharp ones. Cracked saw blades must be removed from service.

Wrenches must not be used when jaws are sprung to the point that slippage occurs. Impact tools such as drift pins, wedges, and chisels must be kept free of mushroomed heads. Iron or steel hand tools may produce sparks that can be an ignition source around flammable substances. Where this hazard exists, spark-resistant tools made of non-ferrous materials should be used where flammable gases, highly volatile liquids, and other explosive substances are stored or used.

41

Hand and Power Tools, U.S. Department of Labor, Occupational Safety & Health Administration, http://www.osha.gov/Publications/osha3080.html.

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2(k)(3) What Are the Dangers of Power Tools?42 Power tools are determined by their power source: electric, pneumatic, liquid fuel, hydraulic, and powder-actuated. Power tools should be equipped with guards and safety switches. Personal protective equipment such as safety goggles and gloves should be worn to protect against hazards that may be encountered while using power tools. To prevent hazards associated with the use of power tools, workers should observe the following general precautions: • • • • • • • • • • •

Never carry a tool by the cord or hose. Never yank the cord or the hose to disconnect it from the receptacle. Keep cords and hoses away from heat, oil, and sharp edges. Disconnect tools when not using them, before servicing and cleaning them, and when changing accessories such as blades, bits, and cutters. Keep all people not involved with the work at a safe distance from the work area. Secure work with clamps or a vise, freeing both hands to operate the tool. Avoid accidental starting. Do not hold fingers on the switch button while carrying a plugged-in tool. Maintain tools with care; keep them sharp and clean for best performance. Follow instructions in the user's manual for lubricating and changing accessories. Be sure to keep good footing and maintain good balance when operating power tools. Wear proper apparel for the task. Loose clothing, ties, or jewelry can become caught in moving parts.

Remove all damaged portable electric tools from use and tag them: "Do Not Use." 2(k)(4) Guards43 The exposed moving parts of power tools need to be safeguarded. Belts, gears, shafts, pulleys, sprockets, spindles, drums, flywheels, chains, or other reciprocating, rotating, or moving parts of equipment must be guarded. Appropriate machine guards must be provided to protect the operator and others from the following: • • • •

Point of operation; In-running nip points; Rotating parts; and Flying chips and sparks.

Safety guards must never be removed when a tool is being used. Portable circular saws having a blade greater than 5.08 centimeters in diameter must be equipped at all times with guards. An 42

Hand and Power Tools, U.S. Department of Labor, Occupational Safety & Health Administration, http://www.osha.gov/Publications/osha3080.html. 43 Ibid.

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upper guard must cover the entire blade of the saw. A retractable lower guard must cover the teeth of the saw, except where it makes contact with the work material. The lower guard must automatically return to the covering position when the tool is withdrawn from the work material. 2(k)(5) Operating Controls and Switches44 The following hand-held power tools must be equipped with a constant-pressure switch or control that shuts off the power when pressure is released: • • • • • • •

drills; tappers; fastener drivers; horizontal, vertical, and angle grinders with wheels more than 5.08 centimeters in diameter; disc sanders with discs greater than 5.08 centimeters; belt sanders; reciprocating saws; saber saws, scroll saws, and jigsaws with blade shanks greater than 0.63 centimeters wide; and other similar tools.

These tools also may be equipped with a "lock-on" control, if it allows the worker to also shut off the control in a single motion using the same finger or fingers. The following hand-held power tools must be equipped with either a positive "on-off" control switch, a constant pressure switch, or a "lock-on" control: • • • •

disc sanders with discs 5.08 centimeters or less in diameter; grinders with wheels 5.08 centimeters or less in diameter; platen sanders, routers, planers, laminate trimmers, nibblers, shears, and scroll saws; and jigsaws, saber and scroll saws with blade shanks a nominal 6.35 millimeters or less in diameter.

Circular saws having a blade diameter greater than 5.08 centimeters, chain saws, and percussion tools with no means of holding accessories securely must be equipped with a constant-pressure switch. 2(k)(6) Electric Tools45 Electrical shocks, which can lead to injuries such as heart failure and burns, are among the major hazards associated with electric-powered tools. In certain instances, even a small amount of electric current can result in fibrillation of the heart and death. Electric tools must have a three-wire cord with a ground and be plugged into a grounded receptacle, be double insulated, or be powered by a low-voltage isolation transformer. Three44

Hand and Power Tools, U.S. Department of Labor, Occupational Safety & Health Administration, http://www.osha.gov/Publications/osha3080.html. 45 Ibid.

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wire cords contain two current-carrying conductors and a grounding conductor. Any time an adapter is used to accommodate a two-hole receptacle, the adapter wire must be attached to a known ground. Never remove the third prong from the plug. Double-insulated tools provide protection against electrical shock without third-wire grounding. On double-insulated tools, an internal layer of protective insulation completely isolates the external housing of the tool. The following general practices should be followed when using electric tools: • • • • • •

Operate electric tools within their design limitations; Use gloves and appropriate safety footwear when using electric tools; Store electric tools in a dry place when not in use; Do not use electric tools in damp or wet locations unless they are approved for that purpose; Keep work areas well lighted when operating electric tools; and Ensure that cords from electric tools do not present a tripping hazard.

In the construction industry, employees who use electric tools must be protected by ground-fault circuit interrupters or an assured equipment-grounding conductor program. 2(k)(7) Portable Abrasive Wheel Tools46 Abrasive wheel tools must be equipped with guards that: (1) cover the spindle end, nut, and flange projections; (2) maintain proper alignment with the wheel; and (3) do not exceed the strength of the fastenings. An abrasive wheel should be: • •

Inspected for damage and should be sound- or ring-tested to ensure that it is free from cracks or defects; and Tested by tapping gently with a light, non-metallic instrument. A stable and undamaged wheel, when tapped, will give a clear metallic tone or "ring."

To prevent an abrasive wheel from cracking, it must fit freely on the spindle. The spindle nut must be tightened enough to hold the wheel in place without distorting the flange. Always follow the manufacturer's recommendations. Take care to ensure that the spindle speed of the machine will not exceed the maximum operating speed marked on the wheel. An abrasive wheel may disintegrate or explode during start-up. Allow the tool to come up to operating speed prior to grinding or cutting. Never stand in the plane of rotation of the wheel as it accelerates to full operating speed. Portable grinding tools need to be equipped with safety guards to protect workers not only from the moving wheel surface, but also from flying fragments in case of wheel breakage.

46

Hand and Power Tools, U.S. Department of Labor, Occupational Safety & Health Administration, http://www.osha.gov/Publications/osha3080.html.

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When using a powered grinder: • • •

Always use eye or face protection; Turn off the power when not in use; and Never clamp a hand-held grinder in a vise.

2(k)(8) Pneumatic Tools47 Pneumatic tools are powered by compressed air and include chippers, drills, hammers, and sanders. There are several dangers associated with the use of pneumatic tools. First and foremost is the danger of getting hit by one of the tool's attachments or by some kind of fastener the worker is using with the tool. Pneumatic tools must be checked to see that the tools are fastened securely to the air hose to prevent them from becoming disconnected. A short wire or positive locking device attaching the air hose to the tool must also be used and will serve as an added safeguard. If an air hose is more than 12.7 millimeters in diameter, a safety excess flow valve must be installed at the source of the air supply to reduce pressure in case of hose failure. In general, the same precautions should be taken with an air hose that are recommended for electric cords, because the hose is subject to the same kind of damage or accidental striking, and because it also presents tripping hazards. When using pneumatic tools, a safety clip or retainer must be installed to prevent attachments such as chisels on a chipping hammer from being ejected during tool operation. Pneumatic tools that shoot nails, rivets, staples, or similar fasteners and operate at pressures more than 6,890 kPa, must be equipped with a special device to keep fasteners from being ejected, unless the muzzle is pressed against the work surface. Airless spray guns that atomize paints and fluids at pressures of 6,890 kPa or more must be equipped with automatic or visible manual safety devices that will prevent pulling the trigger until the safety device is manually released. Eye protection is required, and head and face protection is recommended for employees working with pneumatic tools. Screens must also be set up to protect nearby workers from being struck by flying fragments around chippers, riveting guns, staplers, or air drills.

47

Hand and Power Tools, U.S. Department of Labor, Occupational Safety & Health Administration, http://www.osha.gov/Publications/osha3080.html.

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Compressed air guns should never be pointed toward anyone. Workers should never "dead-end" them against themselves or anyone else. A chip guard must be used when compressed air is used for cleaning. Use of heavy jackhammers can cause fatigue and strains. Heavy rubber grips reduce these effects by providing a secure handhold. Workers operating a jackhammer must wear safety glasses and safety shoes that protect them against injury if the jackhammer slips or falls. A face shield also should be used. Noise is another hazard associated with pneumatic tools. Working with noisy tools such as jackhammers requires proper, effective use of appropriate hearing protection. 2(k)(9) Liquid Fuel Tools48 The most serious hazard associated with the use of fuel-powered tools comes from fuel vapors that can burn or explode and also give off dangerous exhaust fumes. The worker must be careful to handle, transport, and store gas or fuel only in approved flammable liquid containers. Before refilling a fuel-powered tool tank, shut down the engine and allow it to cool to prevent accidental ignition of hazardous vapors. When a fuel-powered tool is used inside a closed area, effective ventilation and/or proper respirators such as atmosphere-supplying respirators must be utilized to avoid breathing carbon monoxide. Fire extinguishers must also be available in the area. 2(k)(10) Powder-Actuated Tools49 Powder-actuated tools operate like a loaded gun and must be treated with extreme caution. When using powder-actuated tools, an employee must wear suitable ear, eye, and face protection. Select a powder level that is suitable for the powder-actuated tool and necessary to do the work. The muzzle end of the tool must have a protective shield or guard centered perpendicular to and concentric with the barrel to confine any fragments or particles that are projected when the tool is fired. A tool containing a high-velocity load must be designed not to fire unless it has this kind of safety device. To prevent the tool from firing accidentally, two separate motions are required for firing. The first motion is to bring the tool into the firing position, and the second motion is to pull the trigger. The tool must not be able to operate until it is pressed against the work surface with a force of at least 2.2 kg greater than the total weight of the tool. If a powder-actuated tool misfires, hold the tool in the operating position for at least 30 seconds before trying to fire it again. If it still will not fire, hold the tool in the operating position for 48

Hand and Power Tools, U.S. Department of Labor, Occupational Safety & Health Administration, http://www.osha.gov/Publications/osha3080.html. 49 Ibid.

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another 30 seconds and then carefully remove the load in accordance with the manufacturer's instructions. This procedure will make the faulty cartridge less likely to explode. The bad cartridge should then be put in water immediately after removal. If the tool develops a defect during use, it should be tagged and must be immediately removed from service. Safety precautions that must be followed when using powder-actuated tools include the following: • • • • • •

Do not use a tool in an explosive or flammable atmosphere. Inspect the tool before using it to determine that it is clean, that all moving parts operate freely, and that the barrel is free from obstructions and has the proper shield, guard, and attachments recommended by the manufacturer. Do not load the tool unless it is to be used immediately. Do not leave a loaded tool unattended, especially where it would be available to unauthorized persons. Keep hands clear of the barrel end. Never point the tool at anyone.

When using powder-actuated tools to apply fasteners, several additional procedures must be followed: • • • • •

Do not fire fasteners into material that would allow the fasteners to pass through to the other side. Do not drive fasteners into very hard or brittle material that might chip or splatter or make the fasteners ricochet. Always use an alignment guide when shooting fasteners into existing holes. When using a high-velocity tool, do not drive fasteners more than 7.62 centimeters from an unsupported edge or corner of material such as brick or concrete. When using a high velocity tool, do not place fasteners in steel any closer than 1.27 centimeters from an unsupported corner edge unless a special guard, fixture, or jig is used.

2(k)(11) Hydraulic Power Tools50 The fluid used in hydraulic power tools must be an approved fire-resistant fluid and must retain its operating characteristics at the most extreme temperatures to which it will be exposed. The exception to fire-resistant fluid involves all hydraulic fluids used for the insulated sections of derrick trucks, aerial lifts, and hydraulic tools that are used on or around energized lines. Do not exceeded the manufacturer's recommended safe operating pressure for hoses, valves, pipes, filters, and other fittings.

50

Hand and Power Tools, U.S. Department of Labor, Occupational Safety & Health Administration, http://www.osha.gov/Publications/osha3080.html.

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All jacks – including lever and ratchet jacks, screw jacks, and hydraulic jacks – must have a stop indicator, and the stop limit must not be exceeded. Also, the manufacturer's load limit must be permanently marked in a prominent place on the jack, and the load limit must not be exceeded. Never use a jack to support a lifted load. Once the load has been lifted, it must immediately be blocked up. Put a block under the base of the jack when the foundation is not firm, and place a block between the jack cap and load if the cap might slip. To set up a jack, make certain of the following: • • • •

The base of the jack rests on a firm, level surface; The jack is correctly centered; The jack head bears against a level surface; and The lift force is applied evenly.

All jacks must be lubricated regularly. Additionally, each jack must be inspected according to the following schedule: • • •

for jacks used continuously or intermittently at one site – inspected at least once every 6 months; for jacks sent out of the shop for special work – inspected when sent out and inspected when returned; and for jacks subjected to abnormal loads or shock – inspected before use and immediately thereafter.

2(k)(12) General Requirements of Safety in Workshops Policy51 The following rules apply to all workshop personnel, whether they are permanently employed in the workshop or just occasional users: • • • • • • • • • • 51

Keep the workshop clean and tidy at all times. Always seek instruction before using an unfamiliar piece of equipment. Only use tools and machines for their intended purpose. Report all damaged equipment and do not use it until it has been repaired by a qualified person. Where machine guards are provide they must be kept in place. Never distract the attention of another staff member when that person is operating equipment and never indulge in horseplay. Always use the appropriate personal protective devices and check that they are clean and in good repair before and after use. Long hair needs to be restrained by either a tie or hat. Never use compressed air for cleaning clothing and machinery. Report all hazards and unsafe conditions and work practices.

The University of Western Australia, Safety in Workshops, Australian Standard, Safety and Health, http://www.safety.uwa.edu.au/policies/safety_in_workshops.

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2(k)(13) Machinery Installation52 Inspect machinery, plant and equipment on delivery to ensure its safety features comply with the requirements of the Department. Inspect each machine prior to commencement of work to ensure that all guards are correctly fitted. Install machinery, plant and equipment so as to ensure that sufficient space and safe footholds are provided around an individual machine to allow for normal operation, group instruction, adjustment and ordinary repairs. 2(k)(14) Machine Controls53 Machine controls should be in accordance with the following requirements: • • •

•

Start-stop controls of the push button type easily visible, readily accessible and incorporating both no-volt and overload release. Start buttons should be shrouded or recessed, colored green and the word START shall be indicated on or near the button. Starting levers and handles should have a provision for automatic retention in the "off" position. Stop buttons shall be long, easy to locate, colored red and clearly marked with an identifying symbol or the word STOP. Each machine shall have a stop control for disconnecting power and the control should be readily and safely accessible to the operator from the normal operating position. Emergency stop buttons of the mushroom-head type, prominently and suitably labeled, should be installed at selected positions so that pressing any one of the buttons will immediately operate the circuit breaker and disconnect the supply from the machines.

2(k)(15) Machine Guards54 Use of any power machinery introduces the danger of personal injury due to pinching, cutting, tearing or crushing. Minimize this danger by the wearing of suitable clothing and fitting suitable guards to protect both the operator and passing traffic. Guards should be made of unperforated material, but designed to allow access for inspection and maintenance. They should not make the operation of the machine more difficult. 2(k)(16) Service Installations55 Design and construct electrical equipment and apparatus to prevent danger from shock and fire and should always be maintained in a safe and good condition. Any electrical equipment should be checked by a qualified electrician at least quarterly and a tagged to identify the type of item concerned, the name of the owner of the item, the license number of the electrical worker who carried out the inspection and test and the date on which the 52

The University of Western Australia, Safety in Workshops, Australian Standard, Safety and Health, http://www.safety.uwa.edu.au/policies/safety_in_workshops. 53 Ibid. 54 Ibid. 55 Ibid.

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inspection and test was carried out. Unqualified persons must not interfere with or alter any electrical installation. All electrical power distribution circuitry should be protected by corebalance earth-leakage protection of 30mA sensitivity. The gas supply must be automatically interrupted at the occurrence of system failure. 2(k)(17) Grinding and Polishing Machines56 Provide every grinding or polishing machine which generates dust with an efficient exhaust system or dust abatement system. The exhaust system should consist of a hood ducted to an exhaust fan in such a manner as to carry away the dust to a device whereby the dust is separated from the air and is prevented from entering the workroom. All personnel engaged in grinding or polishing operations must wear suitable eye protection. Properly mount grinding wheels, and where necessary, fit with a bush of suitable material between the wheel and the spindle. A guard of sufficient mechanical strength should enclose the grinding wheel. It is necessary to prevent vibration, which can be caused by incorrect wheel balance, lack of rigidity in the machine, loose bearings or incorrect use of the work rest. Additionally, incorrect fitting of the belt fasteners for a belt-driven wheel may cause the vibration. Provide an eye screen for hand-held work when using pedestal or bench-type grinding machines. The area of the screen should be large enough to discourage the operator from looking around it. The screen should always be in place and maintained at an adequate transparency. Every grinding wheel should be positioned so that when in use the plane of rotation is not in line with any door, passageway, entrance or a place where someone regularly works. Finishing machines should be guarded with only the working face of the belt exposed and the belt should be mounted such that it rotates away from the operator wherever practicable. Before use the condition of abrasive belt should be examined and replaced if worn and the correctness of the tracking of the belt should be checked by rotating the belt by hand. If necessary the belt should be adjusted and finally checked with a trial run. Where possible suitable jigs or fixtures should be used to hold or locate the work piece. The work piece should never be held in a cloth or any form of pliers and gloves must not be worn when using a finishing machine. 2(k)(18) Milling Machines57 Operators of milling machines should observe the following: • •

56

Exercise care when using fast traverse levers in order to avoid running the job into the cutter and never attempt to remove the arbor nut by applying power to the machine. Clamp the job or vice firmly on the table before starting the machine, and, where necessary, to provide steady supports to prevent vibration.

The University of Western Australia, Safety in Workshops, Australian Standard, Safety and Health, http://www.safety.uwa.edu.au/policies/safety_in_workshops. 57 Ibid.

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Utilize the correct type of handling equipment when heavy cutters are involved and the use of a chip guard when a fly cutter is used. Keep hands and fingers away from the cutters when an unguarded cutter is in motion.

2(k)(19) Metal-Cutting Guillotines58 The following requirements apply to the safe use of metal-cutting guillotines: • • • •

Guards must be provided to prevent the operator's fingers from contacting the knife or clamp from either the front or rear of the machine. Only one person should be allowed to operate the machine at the one time and where long material is being cut and cannot be adequately supported by the work table, additional supports should be provided. The shear edges of the blades should be maintained in good condition and blade clearance must be adjusted in accordance with the manufacturer's recommendation appropriate to the thickness of the material being cut. Waste scrap metal provides a hazard for the hands and protective gloves should be worn when the metal is handled. A container should be provided for waste material from the guillotine.

2(k)(20) General Considerations59 There are several points in relation to chemical safety which are particularly relevant to workshops including: • • • • •

Harmful or potentially harmful processes should be carried out using properly designed and well maintained equipment and where practicable in separate areas restricted to a minimum of persons. If harmful concentrations of fumes or gases develop in certain processes, specific provision should be made for their extraction using local exhaust ventilation in addition to the general ventilation of the workshop. Provision should be made to afford protection against chemical agencies such as harmful dusts, mists, vapors. Chemicals bearing trade names should not be used unless the supplier or manufacturer provides a material safety data sheet giving full information on the precautions which need to be taken when handling the chemical. The possibility of toxic or flammable gases existing or being generated should be indicated by prominently displayed notices.

58

The University of Western Australia, Safety in Workshops, Australian Standard, Safety and Health, http://www.safety.uwa.edu.au/policies/safety_in_workshops. 59 Ibid.

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2(k)(21) Solvent Degreasing60 The following solvents are permitted for use in workshops: •

1,1,1, trichloroethane - should always be used in a fume cupboard and only for small scale operations. – Trichloroethylene & perchloroethylene – Should only be used in equipment specifically designed and in a well ventilated area free from draught. These solvents have anesthetic properties and are harmful when inhaled or on contact with the skin producing:  headaches, nausea, vomiting, mental confusion, visual disturbances, even unconsciousness, and dermatitis.

Do no use caustic alkalis used with trichloroethylene or perchloroethylene as they produce an explosive mixture. The following solvents are prohibited for use in workshops: • •

petrol, kerosene, alcohol, ketones, esters; and carbon tetrachloride.

Solvent degreasing processes should not be carried out near open flames or electric heaters. Mop up spillages with rags or by absorbing in sawdust, dry sand or earth and removing to an open space. Do no use incinerators. 2(k)(22) Bibliography U.S. Department of Labor, Occupational Safety and Health, Hand and Power Tools, http://www.osha.gov/Publications/osha3080.html. The University of Western Australia, Safety in Workshops, Australian Standard, Safety and Health, http://www.safety.uwa.edu.au/policies/safety_in_workshops.

60

The University of Western Australia, Safety in Workshops, Australian Standard, Safety and Health, http://www.safety.uwa.edu.au/policies/safety_in_workshops.

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SEC. 2(l) LINEMEN GENERAL SAFETY PRACTICES CONTENTS 2(l)(1) Introduction ...............................................................................................................II-299 2(l)(2) Scope ...........................................................................................................................II-299 2(l)(3) Shock Hazard Analysis .............................................................................................II-299 2(l)(4) Regulatory Issues.......................................................................................................II-300 2(l)(5) Standard Requirements ............................................................................................II-300 2(l)(6) Test Equipment Industry Recognized Good Practices .........................................II-300 2(l)(7) Flash Hazard Analysis ..............................................................................................II-301 2(l)(8) Blast Hazard Analysis ...............................................................................................II-301 2(l)(9) Selection of Electrical Protective Equipment..........................................................II-302 2(l)(10) Exterior Safety Rules ..............................................................................................II-303 2(l)(10)(i) Rope.................................................................................................................... II-303 2(l)(10)(ii) Body Belts and Safety Straps ............................................................................ II-303 2(l)(10)(iii) Rubber Protective Equipment........................................................................... II-303 2(l)(10)(iv) Gaffs ................................................................................................................. II-304 2(l)(10)(v) Climbers............................................................................................................. II-305 2(l)(10)(vi) Hot-Line Tools.................................................................................................. II-305 2(l)(10)(vii) Vehicles ........................................................................................................... II-306 2(l)(11) Exterior Working Practices....................................................................................II-306 2(l)(11)(i) Excavation .......................................................................................................... II-306 2(l)(11)(ii) Manholes ........................................................................................................... II-306 2(l)(11)(iii) Potheads............................................................................................................ II-307 2(l)(11)(iv) Poles.................................................................................................................. II-307 2(l)(11)(v) Climbing ............................................................................................................ II-307 2(l)(12) Electrical Safety Rules ............................................................................................II-308 2(l)(12)(i) Voltage Low ...................................................................................................... II-308 2(l)(12)(i)(a) Intermediate............................................................................................... II-308 2(l)(12)(i)(b) Checking Energized Conductors............................................................... II-308 2(l)(12)(i)(c) Insulation................................................................................................... II-308 2(l)(12)(ii) High Voltage...................................................................................................... II-310 2(l)(12)(iii) Circuits ............................................................................................................. II-311 2(l)(12)(iii)(a) De-energized ........................................................................................... II-311 2(l)(12)(iii)(b) HOT ........................................................................................................ II-311 2(l)(12)(iii)(c) Protection ................................................................................................ II-312 2(l)(12)(iii)(d) Overload.................................................................................................. II-312 2(l)(12)(iii)(e) Bypassed ................................................................................................ II-312 2(l)(13) Transformers and Circuit Breakers ......................................................................II-312 2(l)(14) Wire Markers...........................................................................................................II-313 2(l)(15) Adequacy and Effectiveness of the Training Program .......................................II-313 2(l)(16) Bibliography.............................................................................................................II-314

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2(l)(1) Introduction61 The subject of electrical hazards analysis has been recognized by a small segment of the electrical industry for many years. However, the electrical industry, most commonly at the user level, has largely ignored the subject, essentially reacting to catastrophic accidents, rather than proactively trying to predict and prevent them. Recent changes in consensus standards, along with a better general understanding of the seriousness of electrical hazards have resulted in a renewal of interest in the subject. 2(l)(2) Scope62 Key definitions that are crucial to understanding shock and arc-flash hazard protection are: • • • •

Limited Approach Boundary - “An approach limit at a distance from an exposed live part within which a shock hazard exists.” Restricted Approach Boundary - “An approach limit at a distance from an exposed live part within which there is an increased risk of shock, due to electric arc over combined with inadvertent movement, for personnel working in close proximity to the live part.” Prohibited Approach Boundary - “An approach limit at a distance from an exposed live part within which work is considered the same as making contact with the live parts.” Flash Protection Boundary - “An approach limit at a distance from exposed live parts within which a person could receive a second degree burn if an electrical arc flash were to occur.”

Additional electrical safety-related work practices must be used if circuits, operating at 50 volts or more, are not de-energized (placed in an electrically safe work condition). Work practices must protect the employee from an arc flash, as well as inadvertent contact with live parts operating at 50 volts or more. Analyses must be performed before an employee approaches exposed live parts, within the Limited Approach Boundary. 2(l)(3) Shock Hazard Analysis63 Inadvertent contact with energized conductors can injure or kill employees. There are several contributing factors to the causes of numerous shock-related injuries and fatalities including: • • • • • • • • •

Poor or faulty insulation; Improper or inadequate grounding; Loose connections; Defective or outdated parts; Ground faults in equipment; Unguarded live parts; Failure to de-energize electrical equipment when it is being repaired or inspected; Intentional use of obviously defective and unsafe tools; or Use of tools or equipment too close to energized parts.

61

National Fire Protection Agency, 70E-2004, “Standard for Electrical Safety in the Workplace.” Ibid. 63 Ibid. 62

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Evaluate the procedures or work practices that will be involved to appropriately assess the electrical shock hazard associated with any type of maintenance or repair work. Evaluate the practices against both regulatory and consensus standards requirements as well as recognized good practice within the industry. 2(l)(4) Regulatory Issues64 • • • •

Place all equipment in a de-energized state prior to any maintenance or repair work. (Limited exceptions exist). A qualified person must verify the de-energized state prior to beginning any work. Maintain the de-energized state through the consistent use of locks and tags, and in some cases, grounding. Perform energized work in accordance with written procedures.65

2(l)(5) Standard Requirements66 •

• • •

The Shock Hazard Analysis must establish the: – Limited Approach Boundary, – Restricted Approach Boundary, and the – Prohibited Approach Boundary. This applies to all exposed live parts operating at 50 volts or more Only qualified persons are permitted within these boundaries. An unqualified person may not enter these boundaries unless the conductors and equipment have been placed in an electrically safe work condition.

2(l)(6) Test Equipment Industry Recognized Good Practices 67 • • • • • •

Plan every job. Anticipate unexpected results and the required action for these results. Use procedures as tools. Identify all hazards. Keep unqualified workers away from hazards. Assess employee’s abilities and qualifications.

Include an assessment of the physical condition of the electrical system. As part of the assessment, identify the proper Personal Protective Equipment (PPE) for shock protection, which would include, but not be limited to, rubber insulating gloves with leather protectors, rubber blankets and mats, and insulated hand tools. Insure that equipment covers and guards are in place; that access to exposed conductors is limited to electrically qualified personnel; and overcurrent protective devices are operable and of appropriate interrupting rating.

64

National Fire Protection Agency, 70E-2004, “Standard for Electrical Safety in the Workplace.” IEEE Conference Record of 2006 Annual Pulp and Paper Industry Technical Conference, June 18-23, 2006 66 National Fire Protection Agency, 70E-2004, “Standard for Electrical Safety in the Workplace.” 67 Ibid. 65

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2(l)(7) Flash Hazard Analysis68 A large number of all serious electrical injures are related to electrical arcs created during short circuits and switching procedures. An electrical arc is basically an electrical current passing through ionized air. This current flow releases a tremendous amount of energy as both radiated light and convected heat. Human errors and equipment malfunctions contribute to the initiation of an electrical arc. Engineering design and construction of arc resistant equipment as well as requirements for safe work practices are continuing to target the risk of electrical arc-flash hazards.69 The principle factors used in the determination of the flash hazards to personnel are: • • • • •

Available short circuit current at the arc location; Duration of the electrical arc; Distance from the arc to personnel; The arc gap; and Environmental conditions and surroundings at the arc location.

Minimizing or eliminating the hazard is the first choice; however, when this is not possible flame-resistant rated clothing and personal protective equipment must be utilized. In addition to flame-resistant clothing and personal protective equipment, there are other safe work practices that can be adopted to minimize or eliminate the hazards including: • • • • •

lockout/tagout along with temporary grounding; body positioning; clothing; insulated tools; and carefully scrutinized to insure that the risk to employees is minimized.

2(l)(8) Blast Hazard Analysis70 During an electrical arc, both the conducting material and the surrounding air are heated to extremely high temperatures. The resulting expansion of the air and vaporized conductive material creates a concussive wave surrounding the arc. Pressures may becomce excessive, destroying equipment enclosures and throwing debris great distances. The pressure created during an electrical explosion is directly proportional to the available short circuit at the arc location. With a current short circuit study available, the anticipated blast pressure can be estimated from tables or charts. Utilize blast pressure calculations to determine whether enclosures will withstand an internal fault if sufficient manufacturer’s data is available. Recognize the magnitude of the hazard so that appropriate safety practices, such as correct body positioning, can be incorporated into work 68

National Fire Protection Agency, 70E-2004, “Standard for Electrical Safety in the Workplace.” IEEE Conference Record of 2006 Annual Pulp and Paper Industry Technical Conference, June 18-23, 2006 70 Ibid. 69

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procedures. Blasts can severely injure or kill a person if the blast hazard is high, or if it is in a limited space. Serious consideration should be given to not allowing personnel in the area during specific equipment operations if these conditions are present. 2(l)(9) Selection of Electrical Protective Equipment71 The requirements for the hazard analysis and selection of protective clothing must first be defined. Assess the workplace to determine if hazards are present, or are likely to be present, which require the use of personal protective equipment. If such hazards are determined, the employer should select and have each employee use, the type of personal productive equipment that will protect the affected employee from the hazards identified in the hazard assessment. Train the employee to be knowledgeable with the following issues and scenarios: • • • • •

When personal productive equipment is necessary; What personal productive equipment is necessary; How to properly don, doff, adjust, and wear personal productive equipment; The limitations of the personal productive equipment; and The proper care, maintenance, useful life, and disposal of personal productive equipment.

Include shock, arc, and blast assessments in the hazard analyses. Identify the selection, inspection, and use requirements for electrical personal productive equipment. Specify the type of clothing that is prohibited. Utilize protective shields, protective barriers, or insulating materials to protect each employee from shock, burns, or other electrically related injuries while that employee is working near exposed energized parts which might be accidentally contacted or where dangerous electric heating or arcing might occur. Protective clothing, including a complete multilayered flash suit with hood and face shield, may be required for the operation, insertion, or removal of a circuit breaker. Calculate the incident energy (in cal/cm2) available at the work site in order to determine and the protective clothing required for the specific task. Additionally, determine a “Flash Protection Boundary” for all energized work. At this boundary, exposed flesh must not receive a seconddegree burn or worse. After determining the type, purchase the necessary protective clothing and train employees on how to properly wear the gear.

71

IEEE Conference Record of 2006 Annual Pulp and Paper Industry Technical Conference, June 18-23, 2006

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2(l)(10) Exterior Safety Rules72 2(l)(10)(i) Rope73 Follow these precautions when using rope: • • • • • • • •

Ensure that any rope used near live conductors or equipment is free of metal strands. Turn in the rope for replacement when the strands become frayed. Keep the rope clean so that sharp particles of solder or other substances cannot cut your hands or rubber gloves. Keep your hands at a safe distance when taking hold of a rope passing through a block. Do not place tape, string, or marlin cord on a rope to repair defects. Never loop a rope over your hand or arm because it could be a tripping hazard while climbing. Never leave uncoiled wire, rope, or other material unguarded on streets, roadways, or alleys because of the potential tripping hazard. Never hang safety lines, ropes, or wires from a pole because they could interfere with passing traffic.

2(l)(10)(ii) Body Belts and Safety Straps74 Inspect all body belts and safety straps during regular tool inspections to determine the condition of all parts. Repair or replace suspect of faulty straps or belts. Ensure that the leather loops holding the D-rings are not worn or crushed enough at the edges to weaken the leather or cause it to tear. If the straps are otherwise sound, utilize them until they are not less than 3.2 milimeters thick in any portion other than the doubled part of the strap. In this portion, the leather may wear slightly less than 3.2 milimeters because a double portion is approximately twice as strong as a single portion. 2(l)(10)(iii) Rubber Protective Equipment75 Follow the safety rules below for inspection, use, and care of rubber protective equipment: Inspection • Ensure that each worker personally tests his rubber gloves before starting work on or near live conductors or equipment carrying between 300 and 5,000 volts. Conduct a thorough visual inspection for holes and thin spots. Immediately tag and turn in rubber gloves or other protective equipment that is believed to be defective. • Perform semiannual electrical test on rubber gloves. Give other rubber protective equipment an electrical test annually. Make arrangements with the servicing utility to conduct these tests.

72

http://www.globalsecurity.org/military/library/policy/army/fm/5-424/chap13.htm Ibid. 74 Ibid. 75 Ibid. 73

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Wear rubber gloves when working on or within reach of energized conductors or equipment operating at voltages between 300 and 5,000 volts. Wear leather protective gloves over rubber gloves to protect them from mechanical damage. Pin holes or thin spots caused by using gloves without protectors may be hazardous to workers. Use approved live-line tools without using rubber gloves for work on lines that are energized at more than 5,000 volts. Wear rubber gloves while cutting supposedly dead cables and while testing supposedly burned-out transformers on both primary and secondary sides. Do not remove rubber gloves until you are entirely out of reach of energized equipment. Do not work with the gauntlet of rubber gloves rolled down. Wear rubber gloves when tending reels when wire is being strung or removed near other wires energized between 300 and 5,000 volts, and if working near someone who is near conductors or equipment energized at voltages between 300 and 5,000 volts. Use a hand line to raise or lower all rubber protective equipment in a canvas tool bag or a bucket.

Care Issue rubber gloves to each lineman and inform the lineman of the following safety precautions and procedures: • • • • • • • •

Store rubber gloves in a canvas bag when they are not in use. Give rubber gloves an air test each day before starting work and when encountering an object that may have damaged the gloves. Wash gloves with warm water and mild detergent. Be careful when applying or removing rubber protective equipment. Do not work over energized conductors or equipment or get in a position that may result in unwanted contact with the equipment. Dry rubber protective equipment before putting it away if possible. Do not carry rubber protective equipment in compartments on trucks or in tool bags with tools or other equipment. Roll, never fold, rubber blankets when putting them away. Place rubber hoods and hoses flat in truck compartments.

2(l)(10)(iv) Gaffs76 Take the following safety measures to ensure that gaffs are the proper length and sharpness: • • • • 76

Do not sharpen gaffs on the underside, except to make the shoulder, because it changes the angle to which they are set and renders the climber unsafe. Make the underside straight when removing metal to make the shoulder. Do not sharpen the gaff with a grindstone or an emery wheel. Place the climber in a vise with the gaff uppermost.

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Sharpen the gaff on the two outer surfaces with a file. Take long strokes from the heel to the point of the gaff. Remove only enough material to make a good point. Never sharpen the gaff to a needlepoint. Leave a shoulder about 3.2 milimeters back from the point. The distance across the gaff at the shoulder should be about 4.0 milimeters. Sharpening the gaff in this manner prevents the point from sinking too far into the pole.

2(l)(10)(v) Climbers77 Take the following precautions and safety measures when using climbers: • • •

Do not use climbers after gaffs are worn shorter than 3.2 centimeters on the underside. Remove climbers when moving from job to job or when working on the ground. Remove climbers before working on a ladder, standing on a rubber blanket, or riding in a vehicle.

2(l)(10)(vi) Hot-Line Tools78 Follow these safety rules when working with hot-line tools: •

•

• • • • • • • • • •

77 78

Do not perform hot-line work when rain or snow is threatening or when heavy dew, fog, or other excessive moisture is present. Exceptions to this rule are when conducting switching operations, fusing, or clearing damaged equipment that presents a hazard to the public or to troops. Remain alert. If rain or snow starts to fall or an electrical storm appears while a job is in progress, complete the work as quickly as possible to allow safe, temporary operation of the line until precipitation or lightning ceases. Judgment of safe weather conditions for hot-line work is the foreman's responsibility. Perform hot-line work during daylight if possible. In emergency situations, work under artificial light if all conductors and equipment being worked on are made clearly visible. Do not wear rubber gloves with hot-line tools because they make detection of brush discharges impossible. Avoid holding outer braces or other metal attachments. Avoid unnecessary conversation. Maintain close cooperation among everyone on the job. Treat wooden pole structures the same as steel towers. Be careful with distribution primaries. When they are located on the same pole with hightension lines, cover them with rubber protective equipment before climbing through or working above them. Do not change your position on the pole without first looking around and informing others. Never use your hands to hold a live line clear of a lineman on a pole. Secure the line with live-line tools and lock it in a clamp. Stay below the live wire when moving it until it is thoroughly secured in a safe working position.

http://www.globalsecurity.org/military/library/policy/army/fm/5-424/chap13.htm Ibid.

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Take special precautions on poles having guy lines. Do not use a rope on conductors carrying more than 5,000 volts unless the rope is insulated from the conductor with an insulated tension link stick.

2(l)(10)(vii) Vehicles79 Follow the safety rules below when operating or working with vehicles: • • •

Never hang coils of wire or rope outside a truck because they could easily catch on passing vehicles. Take care when using materials or tools that extend 1.2 meters or more behind a truck body. Attach a danger flag near the end of the projection during the day, and use a red lantern at night. Provide a red lantern or taillight with any equipment that is being pulled by a truck at night.

2(l)(11) Exterior Working Practices80 2(l)(11)(i) Excavation81 • • • • •

Place necessary barriers, red flags, and warning signs to protect traffic and guard workers when making excavations in or near highways. Place red lights or flares at night to give ample warning to approaching traffic. Place signs between 30.5 meters and 91.4 meters from the outside edge of the work area. Display a “MEN AT WORK” sign or another suitable warning when opening manholes briefly in daytime for inspections, tests, troubleshooting, and so forth. Notify the person in charge when you find obstructions in digging.

2(l)(11)(ii) Manholes82 Rules when working at manholes: • • • • • • • • 79

Make a gas check before opening a manhole cover. Remove or replace manhole covers with cover hooks or other approved tools. Do not enter a manhole until after a gas check has been made. Use a mine safety lamp or a chemical detector to make checks several times throughout the day. Carefully check manholes near gasoline storage tanks. If gas exists, ventilate the manhole with a power blower. Use only gas-proof lights in a manhole if you suspect explosive gases. Assign someone with a red flag or lantern to warn pedestrians and vehicular traffic when a manhole is opened during daylight. At night, mark open manholes.

http://www.globalsecurity.org/military/library/policy/army/fm/5-424/chap13.htm Ibid. 81 Ibid. 82 Ibid. 80

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Ensure the safety of workers in manholes if they cannot be seen by fellow workers on the surface.

2(l)(11)(iii) Potheads83 • • •

Open the neutral pothead last and close it first when opening and closing circuits with potheads. Do not stand on a concrete floor or on the ground while operating potheads in manholes or vaults. Use an insulated stool, a crossarm, or other dry lumber. Cover all grounded framework safely. Keep your body clear of all grounded equipment when working on or near potheads.

2(l)(11)(iv) Poles84 • • • • • • • • • • •

Warn persons nearby when moving a pole by hand, with a pole cart, or with the truck derrick. Station someone with a red flag to warn or stop traffic as necessary. Report poles that appear unsafe for climbing to the foreman so that they can be properly braced or guyed. Do not remove wires or supporting guy lines from a pole until the condition of the butt has been checked. Support unsound poles with pike poles or guy lines before starting excavation or removing wires. Remove all the equipment around the pole being removed before starting excavation. Climb to a working position by the safest path and take the safest position possible, keeping all body parts clear of grounded or live portions of equipment. Do not use pins, braces, or guy lines as handholds. Never carry any tools or material in your hands when climbing. Watch for hazardous and dangerous conditions such as rusted hardware and defective guy lines, braces, and arms. Repair such conditions immediately. When more than one person is ascending or descending, ensure that the first person reaches his working position or the ground before the second person starts to ascend or descend.

2(l)(11)(v) Climbing85 • • •

Exercise caution when climbing past another worker to avoid damaging the safety straps or gaffs. Ensure that the safety strap does not catch on the pole steps when climbing. When wearing a body belt and a safety strap, snap both ends of the strap into the same D-ring when not in the working position. Never put both of the snaps for the safety strap in one D-ring while in the working position on a pole. Ensure that one snap is fastened in each D-ring.

83

http://www.globalsecurity.org/military/library/policy/army/fm/5-424/chap13.htm Ibid. 85 Ibid. 84

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Avoid pressure on the tongue snap when leaning against arms, pins, braces, and wires to prevent the safety snap from becoming disengaged from the D-ring.

2(l)(12) Electrical Safety Rules86 2(l)(12)(i) Voltage Low87 Electricians may work on energized conductors and equipment operating at 300 volts or less if all adjacent energized or grounded conductors and equipment are covered with insulating material or approved rubber protective equipment. Safety precautions and procedures for working on energized conductors and equipment operating at 300 volts or less are as follows: • • • • •

Tape or cover all bare or exposed places on one conductor before exposing another one. Open switches and remove fuses when working on building wiring, motors, belting, shafting, blowers, or other machinery (including shop machine tools). Attach hold cards to the switches. Do not touch steam or water pipes when handling portable electric tools or light cords. Never leave joints or loose ends of wire untaped unless otherwise protected. Never turn on current in a building where a fire has occurred and electric wiring or apparatus has been affected until a careful safety inspection is made by the fire department or a safety inspector.

2(l)(12)(i)(a) Intermediate88 De-energize ground lines and equipment operating between 300 and 5,000 volts before starting any work. The only exception to this is when working on overhead lines. Wear rubber gloves when working on overhead lines. 2(l)(12)(i)(b) Checking Energized Conductors89 Consider conductors and equipment normally operating between 300 and 5,000 volts to be energized until positively proved otherwise. If confirmation cannot be determined by a visual check, use an approved voltage detector. Check the detector on a conductor that is known to be energized and note a positive indication before using it. Repeat this check on a known live conductor after making the test on a dead conductor. If rechecking the voltage detector on a live conductor is impossible, use two voltage detectors, one as a check against the other. 2(l)(12)(i)(c) Insulation90 When working within reach of conductors or equipment operating between 300 and 5,000 volts, all energized and grounded conductors or equipment must be covered with rubber line hose, insulator hoods, line protectors (pigs), or blankets or must be isolated with suitable barriers. 86

http://www.globalsecurity.org/military/library/policy/army/fm/5-424/chap13.htm Ibid. 88 Ibid. 89 Ibid. 90 Ibid. 87

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Cover or barricade any energized or grounded conductors and equipment coming within reach before starting new work. Utilize the following safety precautions when working on equipment and conductors operating at 300 to 5,000 volts: • • • • • • • • • • • • • • • • •

•

De-energize by opening sectionalizing switches and effectively ground the section of line being worked on. Treat line wires being installed on poles as if they were energized when those poles are already carrying energized conductors. Use rope to pull line wires into position. Remove wire from the underside of reels. Ground the truck when using a pay-out reel to string wires near energized wires of this classification. Exercise caution when stringing wire near other wires energized with 300 to 5,000 volts. Ensure that the worker tending the pay-out reel wears rubber gloves and does not allow any part of his body to come in contact with the wire being strung. Apply the brake to the rim of the pay-out reel on the side opposite the direction the wire is being pulled. A crossarm or sidearm may be used as a brake. Hold the loose ends of jumpers in the clear, or have someone at each end hold them if necessary. Keep the tie wire coiled during installation or removal to prevent accidental contact with an energized conductor. Test for voltage before removing a primary or secondary wire. The wire should be rechecked by the foreman to ensure that it is dead. Treat the spans of wire to be removed as energized. Attach a rope to each end and lower the spans one at a time. Make all possible connections to dead wires and equipment with only the final connection made to the energized conductor. Never open the ground connection at a ground pipe or a bus bar unless it has first been disconnected at the point of contact with the equipment it is intended to ground. Make the ground pipe connection first whenever a ground wire on a pole is to be connected. Treat coil wires in the take-up reel that was used to coil the wires as energized when removing the reel from the line arms. Attach a rope to the wires at the end farthest from the take-up reel, and wear rubber gloves when tending the reel. Ensure proper direction of phase rotation when restoring three-phase power service. Identify cable while in the manhole before anyone cuts a cable or makes an opening in the lead sheath or sleeve. Check its duct location with that shown on the working print. Check the working print against the installation engineer's map records. Additionally, check the cable identity by listening with an exploring coil for the pulsating beat of the interrupter signal. Remove a 7.6 centimeter strip of lead around the cable and test it with two voltage detectors after the cable has been identified and grounded. Do this one at a time, at two or more points around the cable and at the center of the exposed insulation.

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Place a hacksaw on the exposed cable insulation adjacent to and touching the grounded lead sheet when cutting cable. Open the switch before working on an oil circuit breaker that has an operating bus feed switch. Treat series circuits, series lamps, and devices in series circuits as energized unless they are opened by disconnects. Never open a series circuit at the point where work is in progress, such as at lamps or other series-circuit devices. Always bridge the point of the circuit being working on with a jumper.

2(l)(12)(ii) High Voltage91 Lines and equipment operating at 5,000 volts or more must be de-energized and grounded before any work is started. An exception is overhead lines, which can be worked on with live-line tools. Follow these rules and procedures when working on high-voltage equipment operating at 5,000 volts or more: • • • • • • • • • • • •

91

Do not work on more than one conductor at a time with live-line tools. Keep live-line tools dry and free from dirt. Dry and test tools subjected to damp weather before using them again. Protect live-line tools carried on line trucks to prevent scars and abrasions. Waterproof canvas bags, compartments with padded hooks, or bins built into the truck may be used for this purpose. Perform all work on de-energized circuits between two sets of grounds. Place one set on the first pole or structure toward the source of energy and the other on the pole nearest the load. Do not ground a supposedly dead circuit without first feeling out the circuit for a static discharge with a switch pole. Net off energized equipment properly at the substation before working near it, and install suitable barriers and warning signs. Remove substation apparatus from service when wiping, cleaning, repairing, or performing other maintenance. Place hold cards on the main and control switches before starting work. Use a red light to illuminate hold cards if they are not distinctly visible. Do not perform work on any apparatus until the electrical foreman has proved it to be dead and safe. Do not approach or touch reactors and connected equipment unless they have been disconnected from all live lines and have been grounded. Do not raise, move, or lower cables that are energized at voltages up to 12 kilovolts more than 45.7 centimeters. Do not move cables that are energized at voltages over 12 kilovolts. Discharge electrolytic and oxide-film lightning arresters by grounding and shorting the horn gaps before touching the arresters.

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Table 23 gives the minimum body clearance from energized lines and equipment.92 Table 23. Minimum Body Clearance Distance

Minimum Distance (meters)

Operating Voltage (kilovolts) 5 to 7.5

.30

7.5 to 12

.61

12 to 33

.91

33 to 66

1.2

66 to 132

1.5

132 to 220

2.4

2(l)(12)(iii) Circuits93 2(l)(12)(iii)(a) De-energized94 Perform all electrical installation work on a de-energized (dead) circuit if possible. Rip the main service-entrance switch, remove the fuses, and tag the switch. The tag should list the electrician's name, the date, and the time that he turned the switch off. If existing conditions do not permit this procedure, de-energize the circuit being repaired or modified by removing the branch circuit fuses or tripping the circuit breaker connected to the branch circuits to OFF. 2(l)(12)(iii)(b) HOT95 Working on hot circuits is not recommended except in emergency situations. Only experienced personnel who have been cautioned on the dangers involved should work on these circuits. AC voltages as low as 67 volts and DC voltages as low as 110 volts have caused death by electrocution. When working on a hot line, closely follow the procedures listed below: • • • •

Insulate yourself to prevent your body from becoming a conductor path for the current flow. Work on only one side of the circuit at a time. Use insulating gloves at all times and stand on nonconducting materials. Ensure that all equipment, tools, and wearing apparel is dry, because dry materials offer more resistance to the flow of electricity than do moistened or wet items.

92

http://www.globalsecurity.org/military/library/policy/army/fm/5-424/chap13.htm Ibid. 94 Ibid. 95 Ibid. 93

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2(l)(12)(iii)(c) Protection96 Fuses or circuit breakers are installed as overload and short-circuit protection for circuit components and connected loads. Limit their selection with regard to ampere rating to the maximum value allowable for the smallest conductor or equipment used in the circuit. 2(l)(12)(iii)(d) Overload97 Determine the cause of trouble and rewire overloaded circuits by increasing the wire size of the run or dividing the connected load into several circuits. 2(l)(12)(iii)(e) Bypassed 98 Do not use jumpers to bypass the fuse, and do not remove the circuit-breaker protection from the circuit except when testing for short circuits. These primary safety devices are of vital importance in a circuit installation. 2(l)(13) Transformers and Circuit Breakers99 Take the following safety precautions when working on transformers and circuit breakers: • • • • • • • • • •

• • 96

Prevent moisture from entering when removing covers from oil-filled transformers. Do not allow tools, bolts, nuts, or similar objects to drop into the transformers. Tie tools or parts with suitable twine. Have workers empty their pockets of lose articles such as knives, keys, and watches. Remove all oil from transformer covers, the floor, and the scaffold to eliminate slipping hazards. Exhaust gaseous vapor with an air blower before allowing work in large transformer cases because they usually contain some gaseous fumes and are not well ventilated. Stay away from the base of the pole or structure while transformers are being raised or lowered. Ensure that anyone working on a pole or structure takes a position above or well clear of transformers while the transformers are being raised or supported with blocks. Ground the secondary side of a transformer before energizing it except when the transformer is part of an ungrounded delta bank. Make an individual secondary-voltage test on all transformers before connecting them to secondary mains. On banks of three transformers connected Y-delta, bring in the primary neutral and leave it connected until the secondary connections have been completed to get a true indication on the lamp tests. Disconnect secondary-phase leads before opening primary cutouts when taking a paralleled transformer out of service. Do not disconnect secondary neutral or ground connections until you have opened the primary cutouts. Do not stand on top of energized transformers unless absolutely necessary and then only with the permission of the foreman and after all possible precautions have been taken.

http://www.globalsecurity.org/military/library/policy/army/fm/5-424/chap13.htm Ibid. 98 Ibid. 99 Ibid. 97

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These precautions include placing a rubber blanket protected with a rubbish bag over the transformer cover. Do not wear climbers. Treat the grounded case of a connected transformer the same as any grounded conductor. Treat the ungrounded case of a connected transformer the same as any energized conductor because the case may become energized if transformer windings break down. Ensure that the breaker cannot be opened or closed automatically before working on an oil circuit breaker and that it is in the open position or the operating mechanism is blocked. Ensure that metal-clad switching equipment is de-energized before working on it. Ensure that regulators are off the automatic position and set in the neutral position before doing any switching on a regulated feeder. Do not break the charging current of a regulator or large substation transformer by opening disconnect switches because a dangerous arc may result. Use oil or air brake switches unless special instructions to do otherwise have been issued by the proper authority. Do not operate outdoor disconnecting switches without using the disconnect pole provided for this purpose. Ensure that all contacts are actually open and that safe clearance is obtained on all three phases each time an air brake switch is opened. Do not depend on the position of the operating handle as evidence that the switch is open. Do not operate switches or disconnect switches without proper authority and then only if thoroughly familiar with the equipment. Remove potential transformer fuses with wooden tongs. Wear rubber gloves and leather over gloves. Do not open or remove disconnect switches when carrying load. First open the oil circuit breaker in series with the switches. Open disconnect switches slowly and reclose immediately if an arc is drawn.

2(l)(14) Wire Markers100 Wire markers are a distinct aid to installation. Use them as a guide, and thoroughly check the condition of each conductor with a test lamp or voltmeter before working on the circuit. 2(l)(15) Adequacy and Effectiveness of the Training Program 101 Ensure adequacy and effectiveness of the electrical safe work practices program and training of qualified electrical personnel by performing the following steps: • •

100 101

Conduct a comprehensive Job Task Analysis. Complete a Task Hazard Assessment including: – Shock hazard, – Arc flash hazard (using current Short Circuit and Coordination Studies), – Blast hazard, and – Other hazards (Slip, fall, struck-by, environmental, etc.).

http://www.globalsecurity.org/military/library/policy/army/fm/5-424/chap13.htm Ibid.

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Analyze task for the Personal Protective Equipment needed. Conduct Training Needs Assessment for Qualified and non-qualified electrical workers.

2(l)(16) Bibliography GlobalSecurity.org, website, http://www.globalsecurity.org/military/library/policy/army/fm/5424/chap13.htm. IEEE Conference Record of 2006 Annual Pulp and Paper Industry Technical Conference, June 18-23, 2006, http://www.electricaltrainingservices.com/common/documents/avotraining/Electrical%20Hazard s%20Analysis.pdf. Nigerian Fire Protection Association, 70E-2004, Standard for Electrical Safety in the Workplace, 2004. Occupational Safety and Health Administration, 29 CFR 1910, Electrical Standards, Federal Register Vol. 46, No. 11, Friday, January 16, 1981. Occupational Safety and Health Administration, 29 CFR 1910.147, Control of Hazardous Energy Source), September 1, 1989. Occupational Safety and Health Administration, 29 CFR 1910.331-.335, Electrical SafetyRelated Work Practices, August 6, 1990. Occupational Safety and Health Administration, 29 CFR 1910.269, Electric Power Generation, Transmission, and Distribution, January 31, 1994.

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SEC. 2(m) ELECTRICAL SAFE WORK PRACTICES PLAN CONTENTS 2(m)(1) Introduction ................................................................................................................. 317 2(m)(2) Training........................................................................................................................ 317 2(m)(3) Qualified Person .......................................................................................................... 317 2(m)(4) Safe Work Practices .................................................................................................... 317 2(m)(4)(i) Lock-out/Tag-out and Safety Related Work Practices ........................................... 317 2(m)(4)(ii) Portable Equipment ............................................................................................... 318 2(m)(4)(iii) Personal Protective Equipment............................................................................. 318 2(m)(4)(iv) Conductive Materials and Equipment .................................................................. 319 2(m)(4)(v) De-energized Parts................................................................................................. 319 2(m)(4)(vi) Energized Parts ..................................................................................................... 319 2(m)(4)(vii) Illumination ......................................................................................................... 320 2(m)(4)(viii) Portable Ladders................................................................................................. 320 2(m)(4)(ix) Reclosing Circuits................................................................................................. 320 2(m)(4)(x) Vehicular and Mechanical Equipment Near Overhead Power Lines .................... 320 2(m)(4)(xi) Electrical Equipment/Machinery .......................................................................... 320 2(m)(4)(xii) GFCI Protection................................................................................................... 320 2(m)(4)(xiii) Wiring................................................................................................................. 321

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2(m)(1) Introduction This safety procedure provides guidelines for safely working around electrical hazards. It includes provisions for training, lockout requirements, and specific types of work practices and the required precautionary practices when using portable electric equipment. The reader may refer to other sections of the Standards for specific guidelines on the use of safety equipment and various safe work practices. 2(m)(2) Training It is the responsibility of each exposed employee’s immediate supervisor to ensure that the employee has received the training necessary to safely perform his or her duties. This training will be given via classroom and on-the-job instruction and is to be documented. Exposed employees shall be trained in and familiar with the safety related work practices required by NERC as they pertain to their respective job assignments. Additional training requirements for Qualified Persons are also mandated. Employees will be trained in specific hazards associated with their potential exposure. This training will include isolation of energy, hazard identification, premises wiring, connection to supply, generation, transmission, distribution installations, clearance distances, use of personal protective equipment and insulated tools, and emergency procedures. 2(m)(3) Qualified Person Those persons who are permitted to work on or near exposed energized parts and are trained in the applicable electrical safe work practices. Qualified Persons shall, at a minimum, be trained in and familiar with: • • •

The skills and techniques necessary to distinguish exposed live parts from other parts of electric equipment. The skills and techniques necessary to determine the nominal voltage of exposed live parts. The clearance distances specified in Table 24 and the corresponding voltage to which the qualified person will be exposed.

2(m)(4) Safe Work Practices 2(m)(4)(i) Lock-out/Tag-out and Safety Related Work Practices All electrical energy sources must be locked out when any employee is exposed to direct or indirect contact with parts of fixed electrical equipment or circuits. Safety related work practices will be used to prevent electric shock or other injuries resulting from either direct or indirect electrical contacts. Safety related work practices will be consistent with the nature and extent of the associated electrical hazards. Specific types of work practices covered by this safety procedure include: • •

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Vehicular and mechanical equipment near overhead lines and underground lines; Illumination; Conductive materials and equipment; Portable Ladders; and Housekeeping.

2(m)(4)(ii) Portable Equipment All portable electric equipment will be handled in such a manner that will not damage or reduce service life. Flexible cords connected to equipment may not be used for raising or lowering equipment and will not be used if damage to the outer insulation is present. Additionally, visual inspections are required and unauthorized alterations of the grounding protection are not allowed to ensure the safety of employees. Prior to each shift, a visual inspection will be performed for external defects and for possible internal damage. Attachment plugs and receptacles may not be connected or altered in a manner that would prevent proper continuity of the equipment grounding conductor. In addition, these devices may not be altered to allow the grounding pole of a plug to be inserted into slots intended for connection to the current-carrying conductors. Portable electric equipment and flexible cords used in highly conductive work locations or in job locations where employees are likely to contact water or conductive liquids shall be approved by the manufacturer for those locations. The hazardous locations that employees should be aware of include, wet locations and locations where combustible or flammable atmospheres are present. For wet locations, employees’ hands will not be wet when plugging and unplugging energized equipment. Energized plug and receptacle connections will be handled only with protective equipment if the condition could provide a conductive path to the employee’s hand (if, for example, a cord connector is wet from being immersed in water). In addition, ground-fault circuit interrupter (GFCI) protection is required for some equipment/locations and is also recommended for use in all wet or highly conductive locations. For combustible/flammable atmospheres, all electric equipment and wiring systems in classified locations must meet The Nigerian Electric Code requirements for that particular classification. 2(m)(4)(iii) Personal Protective Equipment Employees working in confined areas such as electrical vaults or any other area where there are potential electrical hazards will be provided with and use protective equipment that is appropriate for the work to be performed. Examples of Personal Protective Equipment (PPE) which might be needed for protection against electric shock include but are not limited to: • • • • II-318

Nonconductive hard-hats, gloves, and foot protection or insulating mats; Eye and face protection whenever there is danger from electric arcs or flashes; Insulated tools or handling equipment; and Protective shields and barriers to protect against electrical shock and burns.

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Additionally, other ways of protecting employees from the hazards of electrical shock will be implemented, including insulation and guarding of live parts. The insulation must be appropriate for the voltage and the insulating material must be undamaged, clean, and dry. Guarding prevents the employee from coming too close to energized parts. It can be in the form of a physical barricade or it can be provided by installing the live parts out of reach from the working surface. 2(m)(4)(iv) Conductive Materials and Equipment Conductive materials and equipment (e.g., hand tools) will be handled to prevent contact with exposed energized conductors or circuit parts. Conductive articles of jewelry and clothing (such as watch bands, bracelets, rings, key chains, necklaces, metalized aprons, cloth with conductive thread, or metal headgear) will not be worn. 2(m)(4)(v) De-energized Parts All electrical parts exceeding 50 volts will be de-energized before an employee works on or near equipment unless: • • •

The de-energizing creates a more hazardous situation; The equipment, by design, cannot be shut down; and/or The decision to work without de-energizing shall be made by management and documented before work begins.

When any employee is exposed to direct or indirect contact with parts of fixed electrical equipment or circuits which have been de-energized, the electrical energy source will be locked out. 2(m)(4)(vi) Energized Parts If work must be performed while equipment is energized or if de-energizing is not feasible, additional safety measures will be taken to ensure the safety of the qualified employee and any other persons who may be exposed. Protection from energized parts will be suitable for the type of hazard involved. Exposed energized parts in areas accessible to the public shall be continuously protected by an authorized attendant. In areas not accessible to the public, employees shall be protected from exposed energized parts by the use of signs or tags. In addition to signs or tags, barricades shall be used where necessary to limit access to areas with exposed energized parts. Only Qualified Persons will be allowed to perform work directly on energized parts or equipment. Qualified Persons will be capable of working safely on energized circuits and will be familiar with special precautionary techniques, personal protective equipment, insulating and shielding materials and insulated tools. Qualified Persons must also have received the training required in this safety procedure.

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2(m)(4)(vii) Illumination Employees will be provided with adequate light to work on energized equipment or equipment will be relocated to ensure adequate light is available. 2(m)(4)(viii) Portable Ladders Portable ladders will have nonconductive surfaces if they are used where the employee or the ladder could be exposed to electrical shock hazards. 2(m)(4)(ix) Reclosing Circuits If circuits are tripped using a protective device such as ground fault circuit interrupter (GFCI), power will not be restored until the reason for the interruption is determined and corrected. Fuses or breakers will not be replaced or reset until it is determined that the circuit is safe to operate. Fuses will not be replaced with higher rated fuses or with makeshift devices to bypass circuit protection as designed. Problems will be identified and promptly repaired by a qualified person. 2(m)(4)(x) Vehicular and Mechanical Equipment Near Overhead Power Lines Overhead power lines will be de-energized and grounded before any work is performed by any vehicle or mechanical equipment near the energized overhead power lines. If the overhead lines can not be de-energized, then the vehicle or mechanical equipment will be operated so that a clearance of 3.1 meters is maintained. If the voltage of the overhead line exceeds 50 kV, the distance will be increased 10.1 centimeters for every 10 kV increase in power. If lines are protected with properly rated insulating devices, the distance may be decreased. If the equipment is an aerial lift insulated for the voltage involved and if the work is performed by a Qualified Person, the clearance may be reduced to a distance given in Table 24. If protective measures such as guarding or isolation are provided, these measures must protect the employee from contacting such lines directly with any part of the body or indirectly through conductive materials, tools, or equipment. 2(m)(4)(xi) Electrical Equipment/Machinery All electrical equipment and machinery must be grounded effectively so that there is no potential difference between the metal enclosures. Use the voltage detector to find discrepancies and other test equipment to determine the corrective action required. Disconnects should be easily identified with the specific machinery they shut off. Disconnects should also be accessible near the machinery for use in an emergency. The disconnects should be activated periodically to be sure they are operable. All electrical connections to the equipment must be secure so that no cord or cable tension will be transmitted to the electrical terminals within the equipment. The wiring installation should be such that it is protected from damage at all times 2(m)(4)(xii) GFCI Protection Generally, GFCI protection is not required by the NEC on a retroactive basis. Where there is an employee exposure to potential line-to-ground shock hazards, GFCI protection should be provided. This is especially important in work areas where portable electrical equipment is being used in wet or damp areas in contact with earth or grounded conductive surfaces. II-320

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2(m)(4)(xiii) Wiring Temporary wiring that is being used on a permanent basis should be replaced with fixed wiring. Conduit and/or cable systems must be protected from damage by vehicles or other mobile equipment. All fittings and connections to junction boxes and other equipment must be secure. No exposed wiring can be allowed. Check for missing knockouts and cover plates. Jerry-rigged splices on flexible cords and cables should be correctly repaired. Electrical equipment should be installed in a neat and professional manner. Check for damaged insulation on flexible cords and pendant drop cords. Table 24. Approach Distance for Qualified Employees

Alternating Current 300V and less Over 300V, but less than 750V Over 750V, but less than 2kV Over 2kV, but less than 15kV Over 15kV, but less than 37kV Over 37kV, but less than 87.5kV Over 87.5kV, but less than 121kV Over 121kV, but less than 140kV

Distance Avoid Contact 30.5 cm 46 cm 61 cm 91 cm 107 cm 122 cm 137 cm

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SEC. 2(n) ELECTRICAL EQUIPMENT CONTENTS 2(n)(1) Introduction ..............................................................................................................II-325 2(n)(2) Electrical Safety Facts..............................................................................................II-325 2(n)(3) Vehicular and Mechanical Equipment...................................................................II-326 2(n)(4) Use of Equipment .....................................................................................................II-327 2(n)(5) Test Equipment.........................................................................................................II-328 2(n)(6) Bibliography..............................................................................................................II-328

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2(n)(1) Introduction Ensure that all individuals are protected from accidental or unexpected activation of mechanical and/or electrical equipment during the maintenance, repairing, cleaning, servicing, and/or adjusting of machinery or equipment. 2(n)(2) Electrical Safety Facts102 Risks associated with the use of electricity include electrical shock and electrical fires are caused by shorts and overloaded circuits or wiring. Sparks from electrical equipment can act as a source of ignition for flammable or explosive vapors or combustible materials. Rules and procedures to reduce the electrical hazards in the workplace: 1. Know the location of electrical panels and disconnect switches in or near your work area so that power can be quickly shut down in the event of a fire or electrical accident. To enhance safety, post the location of the electrical panel on the equipment it services. 2. Label electrical panels to indicate what equipment or power source they control. A minimum .91 meter clearance must be maintained around electrical panels at all times to permit ready and safe operation and maintenance of such equipment. 3. Do not overload circuits or wiring. Overloading can lead to overheated wires and arcing, which can cause fires and electrical shock injuries. 4. Inspect all electrical equipment before use to ensure that cords and plugs are in good condition – not worn, twisted, frayed, abraded, corroded, or with exposed wires or missing ground pins. Live parts must be effectively insulated or physically guarded. Equipment with damaged or defective cords or plugs should be taken out of service immediately and repaired by qualified personnel. 5. Ensure that all electrical outlets have a grounding connection requiring a three-pronged plug. All electrical equipment should have three-pronged, grounded plugs or be doubleinsulated. 6. Ensure that electrical outlets, wiring, and other electrical equipment integral to the building are only serviced and repaired by qualified trades personnel or other qualified electricians. 7. Work on electrical equipment must be done only after the power has been disconnected. The power cord must be unplugged and under the exclusive control of the person performing the work so that the equipment cannot be accidentally turned on by someone else. The main disconnect device or circuit breaker must be shut off and locked and tagged with a special padlock and tag. Service and/or repair work on hard-wired equipment may only be carried out by authorized individuals who have received Lockout/Tag out training. 8. Limit the use of extension cords. In all other cases, request the installation of a new electrical outlet. Do not use extension cords as substitution for fixed receptacle outlets. Long-term use of extension cords is a violation. The long-term use of multi-outlet power strips is also illegal, except for use with computer equipment.

102

U.S. Occupational Safety and Health Administration, Standard 29 CFR 1910, Subpart S - Electrical http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_id=9911&p_table=STANDARDS

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9. Ensure that all extension cords used are carefully placed, visible, and not subject to damage. Cords must not run across aisles or corridors where they might be damaged or create a tripping hazard. Cords must not run through doors, walls or partitions, under rugs, or above dropped ceilings. They must not be tied in knots, draped overhead, or attached to walls. 10. Ensure that the wire size of an extension cord is adequate for the current to be carried. Failure to do so can lead to electrical fires. Cords used for 110-120 volt service should be UL listed with a polarized three prong plug. Extension cords must never be linked together—use the proper length extension cord needed for the application. 11. Keep corrosive chemicals and organic solvents away from electrical cord—these can easily erode the insulation on wires. 12. Keep flammable materials away from electrical equipment. 13. Keep electrical equipment away from wet or damp locations or potential water spillage, unless specifically rated for use under such conditions. 14. Do not handle electrical equipment when hands, feet, or body are wet or perspiring or when standing on a wet floor. 15. Do not sure adapters which interrupt continuity of equipment grounding connections. 16. Ensure that only authorized workers perform testing work on electric circuits or equipment that may expose them to shock or arc-flash hazard. 17. Do not reset a circuit breaker that has tripped unless it has been determined that the equipment and circuit can be safely energized. 18. Do not remove covers from electrical equipment that could expose energized uninsulated parts. Keep space clear around electrical; ensure that nothing is stored in this dedicated space. Marking the floor to indicate the following dimensions is encouraged: a. 91.4 centimeters for 150 volts to ground or less; b. 106.7 centimeters for 151 volts to 600 volts; c. Width of 76.2 centimeters or width of equipment, whichever is greater. 2(n)(3) Vehicular and Mechanical Equipment103 Maintain a clearance of 305cm for all vehicles or mechanical equipment capable of having parts or its structure elevated near energized overhead lines such as cranes, mobile scaffolds, elevating platforms, dump trucks, lift trucks, flatbed trailer cranes, etc. Clearance is increased 10 cm for every 10 kV over 50kV if the voltage of the overhead line is more than 50 kV. Under any of the following conditions, the above clearance may be reduced: • •

103

For vehicles in transit with its structure lowered, the clearance may be reduced to 122 cm for 50 kV or 122 cm plus 10.2 cm for every 10 kV over 50 kV. The clearance may be reduced to distance within the designed working dimensions of the insulating barrier if the insulating barriers are installed to avoid contact with the lines and

U.S. Occupational Safety and Health Administration, Standard 29 CFR 1910, Subpart S - Electrical http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_id=9911&p_table=STANDARDS

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if the barriers are rated for the voltage of the line being guarded and are not a part of an attachment to the vehicle or its elevated structure. The clearance between the un-insulated portion of the lift and the power line may be reduced to distance given in the above if the equipment is an aerial lift insulated for the voltage involved, and if the work is performed by a qualified person. When working on the ground, avoid contact with the vehicle or mechanical equipment or any of its attachments, unless: Using protective equipment rated for the voltage; or if the equipment is positioned so that no un-insulated part may provide a conductive part to individuals on the ground can come closer to the line than 3.05 meters or 3.15 meters for every ten (10) kV over 50 kV. Individuals may not work on the ground when any vehicle or mechanical equipment has elevated part near energized overhead lines and is grounded due to possible overhead line contact. Additional precautionary measures should be taken as necessary to protect individuals from hazardous ground conditions which can develop within a few feet from the grounding point such as barricades or insulation.

2(n)(4) Use of Equipment104 Handling Portable equipment can not be handled in a way which will cause damage. Flexible cords connected to the equipment can not be used for raising or lowering equipment. The flexible cords can not be fastened with staples or hung in a manner which would cause damage to the outer jacket or the insulation. Visual Inspection 1. Inspect portable cord-and plugged-connected equipment and flexible cord sets (extension cords) before use on any shift for external defects such as loose parts, deformed and missing pins, or damage to the outer jacket or insulation and for possible internal damage such as pinched or crushed outer jacket. 2. Remove the defected or damaged item from service which might expose employees to injury are detected, and prevent employees from using it until it is repaired and tested to ensure it is safe to use. 3. Ensure the plug and receptacle contacts match prior to connecting an attachment to a receptacle. Grounding-type Equipment 1. Flexible cords used with grounding-type equipment must contain an equipment grounding conductor. 2. Attachment plugs and receptacles are not connected or altered in a manner which prevents proper continuity of the ground the point where plugs are attached to receptacles. 3. Plugs and receptacle are not altered to allow the grounding pole to be inserted into current connector slots.

104

U.S. Occupational Safety and Health Administration, Standard 29 CFR 1910, Subpart S - Electrical http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_id=9911&p_table=STANDARDS

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4. Adapters which interrupt the continuity of the equipment grounding connection are not used. Conductive Work Locations All portable electric equipment and flexible cords used in highly conductive work locations, such as those with water or other conductive liquids, or in places where employees are likely to contact water or conductive liquids, require approval for those locations. Connecting Attachment Plugs 1. Ensure that hands are not wet when plugging and unplugging flexible cords and cordand-plug-connected equipment, if energized equipment is involved. 2. Handle the he energized plug and receptacle connectors with insulated protective equipment if the cord connectors are wet from immersion in water or if the condition of the connection could provide a conducting path. 2(n)(5) Test Equipment105 1. Ensure only qualified individuals are permitted to perform testing work on electric circuits or equipment. 2. Visually inspect all test equipment and all associated test leads, cables, power cords, probes for external defects and damage prior to use. 3. Remove defected or damaged equipment from service that might pose cause injury to an employee and prohibit use until the equipment is repaired and tested. 4. Test equipment and accessories, and make sure they are rated for the circuits for the environment in which they are utilized. 2(n)(6) Bibliography Environmental Health & Safety, Lockout/Tagout Procedure, Sonoma State University, http://www.sonoma.edu/ehs/esp/LOTOp.shtml. Nigerian Fire Protection Association, 70E-2004, Standard for Electrical Safety in the Workplace, 2004. U.S. Occupational Safety and Health Administration, Standard 29 CFR 1910, Subpart S Electrical http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=101 35.

105

U.S. Occupational Safety and Health Administration, Standard 29 CFR 1910, Subpart S - Electrical http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_id=9911&p_table=STANDARDS

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SEC. 2(o) LADDER SAFETY CONTENTS 2(o)(1) Introduction ..............................................................................................................II-331 2(o)(2) General Requirements .............................................................................................II-331 2(o)(2)(i) Rules for All Ladder Types ................................................................................. II-331 2(o)(2)(ii) Rules for Specific Types of Ladder .................................................................... II-332 2(o)(3) Ladder Hazards/Prevention Tips............................................................................II-336 2(o)(4) Ladder Selection .......................................................................................................II-336 2(o)(5) Ladder Maintenance ................................................................................................II-336 2(o)(5)(i) Using Extension Ladders ..................................................................................... II-337 2(o)(5)(ii) Setting Up an Extension Ladder ......................................................................... II-337 2(o)(5)(iii) Climbing a Fixed Ladder................................................................................... II-338 2(o)(6) Ladder Inspections ...................................................................................................II-338 2(o)(7) Bibliography..............................................................................................................II-339

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2(o)(1) Introduction Ladders are major sources of injuries and fatalities among construction workers for example, and many of the injuries are serious enough to require time off the job. Although ladders are uncomplicated, planning and care are still required to use them safely. 2(o)(2) General Requirements106 • • •

Provide a ladder at all worker points of access if there is a break in elevation of 48 cm or more and no ramp, runway, embankment or personnel hoist is available. Keep the access point clear of obstacles to permit free passage by workers if there is only one point of access between levels. Employers must provide a second point of access if free passage becomes restricted. Ensure that at least one point of access remains clear when there are more than two points of access between levels.

Install all ladder fall protection systems required by these rules and ensure that their worksite meets all requirements of the ladder rules before employees use ladders. 2(o)(2)(i) Rules for All Ladder Types107 Apply the following rules when using all types of ladders: • • • • • • • • • • • • • •

Maintain ladders free of oil, grease and other slipping hazards. Do not load ladders beyond their maximum intended load nor beyond their manufacturer’s rated capacity. Only use ladders for their designed purpose. Only use ladders on stable and level surfaces unless secured to prevent accidental movement. Do not use ladders on slippery surfaces unless secured or provided with slip-resistant feet to prevent accidental movement. Secure ladders placed in areas such as passageways, doorways or driveways, or where they can be displaced by workplace activities or traffic to prevent accidental movement. Use a barricade to keep traffic or activity away from the ladder. Keep areas clear around the top and bottom of ladders. Do not move, shift or extend ladders while in use. Use ladders equipped with nonconductive side rails if the worker or the ladder could contact exposed energized electrical equipment. Face the ladder when moving up or down. Use at least one hand to grasp the ladder when climbing. Do not carry objects or loads that could cause loss of balance and falling. Apply the additional general requirements to all ladders, including ladders built at the jobsite:

106

U.S. Occupational Safety and Health Administration, 29 CFR 3124-12R, 2003. http://www.osha.gov/Publications/osha3124.pdf. 107 Ibid.

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Double-cleated ladders or two or more ladders must be provided when ladders are the only way to enter or exit a work area where 25 or more employees work or when a ladder serves simultaneous two-way traffic. Ladder rungs, cleats and steps must be parallel, level and uniformly spaced when the ladder is in position for use. Rungs, cleats and steps of portable and fixed ladders (except as provided below) must not be spaced less than 25 cm apart, nor more than 36 cm apart, along the ladder’s side rails. Rungs, cleats and steps of step stools must not be less than 20 cm apart, nor more than 31 cm apart, between center lines of the rungs, cleats and steps. Rungs, cleats and steps at the base section of extension trestle ladders must not be less than 20 cm nor more than 46 cm apart, between center lines of the rungs, cleats and steps. The rung spacing on the extension section must not be less 15 cm nor more than 31 cm. Ladders must not be tied or fastened together to create longer sections unless they are specifically designed for such use. When splicing side rails, the resulting side rail must be equivalent in strength to a one-piece side rail made of the same material. Two or more separate ladders used to reach an elevated work area must be offset with a platform or landing between the ladders, except when portable ladders are used to gain access to fixed ladders. Ladder components must be surfaced to prevent snagging of clothing and injury from punctures or lacerations. Wood ladders must not be coated with any opaque covering except for identification or warning labels, which may be placed only on one face of a side rail.

2(o)(2)(ii) Rules for Specific Types of Ladder108 • • •

Do not use single-rail ladders. Use non-self-supporting ladders at an angle where the horizontal distance from the top support to the foot of the ladder is approximately one-quarter of the working length of the ladder. Use wooden ladders built at the jobsite with spliced side rails at an angle where the horizontal distance is one-eighth of the working length of the ladder.

Stepladders109 • Do not use the top or top step of a stepladder as a step. • Do not use cross bracing on the rear section of stepladders for climbing unless the ladders are designed and provided with steps for climbing on both front and rear sections. • Provide metal spreader or locking devices must be on stepladders to hold the front and back sections in an open position when ladders are being used.

108

U.S. Occupational Safety and Health Administration, 29 CFR 3124-12R, 2003. http://www.osha.gov/Publications/osha3124.pdf. 109 Ibid.

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Portable Ladders110 • Minimum clear distance between side rails for all portable ladders must be 29 cm. • Rungs and steps of portable metal ladders must be corrugated, knurled, dimpled, coated with skid-resistant material or treated to minimize slipping. • Non-self-supporting and self-supporting portable ladders must support at least four times the maximum intended load; extra heavy-duty type 1A metal or plastic ladders must sustain 3.3 times the maximum intended load. • Extend side rails at least .9 m above the upper landing surface when portable ladders are used for access to an upper landing surface. If such an extension is not possible, secure the ladder and use a grasping device such as a grab rail to assist workers in mounting and dismounting the ladder. Fixed Ladders111 If the total length of the climb on a fixed ladder equals or exceeds 7.3 m, the ladder must be equipped with: • •

self-retracting lifelines and rest platforms at intervals not to exceed 45.7 m; or a cage or well and multiple ladder sections with each ladder section not to exceed 15.2 m in length.

Sections ladders must be offset from adjacent sections and landing platforms must be provided at maximum intervals of 15.2 m. Fixed ladders should also meet the following requirements and standards: • •

• • • •

Able to support at least two loads of 114 kg each, concentrated between any two consecutive attachments. Must also support added anticipated loads caused by ice buildup, winds, rigging and impact loads resulting from using ladder safety devices. Extend individual rung/step ladders at least 1.1 m above an access level or landing platform either by the continuation of the rung spacings as horizontal grab bars or by providing vertical grab bars that must have the same lateral spacing as the vertical legs of the ladder rails. Each step or rung of a fixed ladder must be able to support a load of at least 114 kg applied in the middle of the step or rung. Minimum clear distance between the sides of individual rung/step ladders and between the side rails of other fixed ladders must be 41 cm. Rungs of individual rung/step ladders must be shaped to prevent slipping off the end of the rungs. Minimum perpendicular clearance between fixed ladder rungs, cleats, and steps and any obstruction behind the ladder must be 18 cm, except that the clearance for an elevator pit ladder must be 11 cm.

110

U.S. Occupational Safety and Health Administration, 29 CFR 3124-12R, 2003. http://www.osha.gov/Publications/osha3124.pdf. 111 Ibid.

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Minimum perpendicular clearance between the centerline of fixed ladder rungs, cleats and steps, and any obstruction on the climbing side of the ladder must be 76 cm. If obstructions are unavoidable, clearance may be reduced to 61 cm, provided a deflection device is installed to guide workers around the obstruction. Step-across distance between the center of the steps or rungs of fixed ladders and the nearest edge of a landing area must be no less than 18 cm and no more than 30 cm. Provide a landing platform if the step-across distance exceeds 30 cm. Fixed ladders without cages or wells must have at least a 38 cm clearance width to the nearest permanent object on each side of the centerline of the ladder. Provide fixed ladders with cages, wells, ladder safety devices or self-retracting lifelines where the length of climb is less than 7.3 m but the top of the ladder is at a distance greater than 7.3 m above lower levels. Side rails of through or side-step fixed ladders must extend 1.1 m above the top level or landing platform served by the ladder. Parapet ladders must have an access level at the roof if the parapet is cut to permit passage through it. If the parapet is continuous, the access level is the top of the parapet. Steps or rungs for through-fixed-ladder extensions must be omitted from the extension; and the extension of side rails must be flared to provide between 61 cm and 76 cm clearance between side rails. Maximum clearance distance between side rail extensions must not exceed 91 cm when safety devices are provided. Use fixed ladders at a pitch no greater than 90 degrees from the horizontal, measured from the back side of the ladder.

Cages for Fixed Ladders112 The requirements for cages for fixed ladders are as follows: • • • • • • • • •

112

Fastened horizontal bands to the side rails of rail ladders or directly to the structure, building or equipment for individual-rung ladders. Position vertical bars on the inside of the horizontal bands. Fasten vertical bars to the horizontal bands. Cages must not extend less than 68 cm, or more than 76 cm from the centerline of the step or rung and must not be less than 68 cm wide. Clear insides of cages of projections. Space horizontal bands at intervals not more than 1.2 m apart measured from centerline to centerline. Space vertical bars at intervals not more than 24 cm, measured centerline to centerline. Bottoms of cages must be between 2.1 m and 2.4 m above the point of access to the bottom of the ladder. Flare bottom of the cage not less than 10 cm between the bottom horizontal band and the next higher band.

U.S. Occupational Safety and Health Administration, 29 CFR 3124-12R, 2003. http://www.osha.gov/Publications/osha3124.pdf.

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Tops of cages must be a minimum of 1.1 m above the top of the platform or the point of access at the top of the ladder. There must be a way to access the platform or other point of access.

Wells for Fixed Ladders113 • Wells must completely encircle the ladder. • Wells must be free of projections. • Inside faces of wells on the climbing side of the ladder must extend between 68 cm and 76 cm from the centerline of the step or rung. • Inside widths of wells must be at least 76 cm. • Bottoms of wells above the point of access to the bottom of the ladder must be between 2.1 m and 2.4 m. Ladder Safety Devices and Related Support Systems for Fixed Ladders114 • Connection between the carrier or lifeline and the point of attachment to the body belt or harness must not exceed 23 cm in length. • All safety devices must be able to withstand, without failure, a drop test consisting of a 226 kg weight dropping 41 cm. • All safety devices must permit the worker to ascend or descend without continually having to hold, push or pull any part of the device, leaving both hands free for climbing. • All safety devices must be activated within .61 m after a fall occurs and limit the descending velocity of an employee to 2.1 m/sec or less. Requirements for Mounting Ladder Safety Devices for Fixed Ladders115 • Attach mountings for rigid carriers at each end of the carrier, with intermediate mountings spaced along the entire length of the carrier. • Attach mountings for flexible carriers at each end of the carrier. Installed cable guides for flexible carriers with a spacing between 7.6 m and 12.2 m along the entire length of the carrier. • Side rails and steps or rungs for side-step fixed ladders must be continuous in extension. Defective Ladders116 Ladders needing repairs are subject to the following rules: • • •

Immediately label portable ladders with structural defects as defective or tagged with "Do Not Use" or similar language. Withdraw ladder from service until repaired. Withdraw fixed ladders with structural defects from service until repaired. Ladder must be restored to a condition meeting its original design criteria before the ladder is returned to use.

113

U.S. Occupational Safety and Health Administration, 29 CFR 3124-12R, 2003. http://www.osha.gov/Publications/osha3124.pdf. 114 Ibid. 115 Ibid. 116 Ibid.

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2(o)(3) Ladder Hazards/Prevention Tips 117 Ladder accidents usually are caused by improper selection, care or use, not by manufacturing defects. Some of the more common hazards involving ladders, such as instability, electrical shock, and falls, can be predicted and prevented. Prevention requires proper planning, correct ladder selection, good work procedures and adequate ladder maintenance. Prevention tips: • • • • • • • • • •

Do not hand-carry loads on a ladder. Move the ladder rather than to over-extend or over-reach. Non-skid feet or spurs may prevent a ladder from slipping on a hard, smooth surface. Do not stand on top three rungs of the ladder. A damaged side rail may cause one side of a ladder to give way. The base should be spaced 30.5 centimeters away for every 121.9 centimeters it reaches up. Ladders used to reach a walking surface or roof must extend at least 91.4 centimeters beyond. Extension ladders need both locks holding to prevent overloading a rail. Step ladders should be securely spread open. Never use a folding step ladder in an unfolded position. Electrical shock can occur with metal or wet wooden ladders.

2(o)(4) Ladder Selection118 Ladders are constructed under three general classes: • • •

Type I Industrial - Heavy-duty with a load capacity not more than 113.4 kg; Type II Commercial - Medium-duty with a load capacity not more than 102.7 kg (suited for painting and similar tasks); and Type III Household - Light-duty with a load capacity of 90.72 kg.

2(o)(5) Ladder Maintenance119 Protect wooden ladders with a clear sealer varnish, shellac, linseed oil or wood preservative. Do not paint wooden ladders. Check and inspect for cracks, rot, splinters, broken rungs, loose joints and bolts and hardware in poor condition. Inspect aluminum or steel ladders for rough burrs and sharp edges before use. Inspect closely for loose joints and bolts, faulty welds and cracks. Make sure the hooks and locks on extension ladders are in good condition. Replace worn or frayed ropes on extension ladders at once.

117

U.S. Occupational Safety and Health Administration, 29 CFR 3124-12R, 2003. http://www.osha.gov/Publications/osha3124.pdf. 118 Ibid. 119 Ibid.

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Fiberglass ladders should have a surface coat of lacquer maintained. If scratched beyond normal wear, lightly sand before applying a coat of lacquer. 2(o)(5)(i) Using Extension Ladders120 • • • • • •

• • • • • • • • •

Place ladders on a firm, level surface and ensure the footing is secure. Erect extension ladders so that the upper section rests on (e.g., in front of) the bottom section. This means the bottom section "faces" a wall or other supporting surface. Place the ladder feet so that the horizontal distance between the feet and the top support is 1/4 of the working length of the ladder. The ladder will be leaning at a 75° angle from the ground. Raise and lower ladders from the ground. Ensure that locking ladder hooks are secure before climbing. Erect ladders so that a minimum of 1 m extends above a landing platform. Tie the top at support points. Where a ladder cannot be tied off at the top, station a person at the foot to prevent it from slipping. This method is only effective for ladders up to 5 m long. The person at the foot of the ladder should face the ladder with a hand on each side rail and with one foot resting on the bottom rung. Leave all tie-off devices in place until they must be removed before taking the ladder down. Maintain the minimum overlap of sections as shown on a ladder label. Refer to safety regulations. Do not use ladders near electrical wire. Do not set up or take a ladder down when it is extended. Do not overextend. Maintain minimum overlap of sections. Do not climb higher than the fourth rung from the top of a ladder. Do not use ladders on ice, snow or other slippery surfaces without securing ladders' feet. Do not extend top section of a ladder from above or by "bouncing" on a ladder. Do not leave ladders unattended.

2(o)(5)(ii) Setting Up an Extension Ladder121 • • • •

Lay a ladder on the ground close to intended location. Brace ladder base using helpers' feet. Grasp the top rung with both hands, raise the top end over your head and walk toward the base of a ladder. Grasp the centre of the rungs to maintain stability. Move the erect ladder to the desired location. Lean it forward against the resting point.

To erect a shorter extension ladder: • •

Place the bottom of a ladder firmly against the base of a building or stationary object. Lift the top of ladder, and pull upwards to raise a ladder to a vertical position.

120

U.S. Occupational Safety and Health Administration, 29 CFR 3124-12R, 2003. http://www.osha.gov/Publications/osha3124.pdf. 121 Ibid.

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Transfer a ladder to its required position when it is erect. Keep a ladder upright and close to the body with a firm grip.

2(o)(5)(iii) Climbing a Fixed Ladder122 • • • • • • • •

Wait until the other person has exited before ascending or descending. Use the appropriate safety devices (e.g., restraint belt, traveling fixture). Maintain three-point contact by keeping two hands and one foot, or two feet and one hand on a ladder always. Face ladder and use both hands to grip the rungs firmly. Place feet firmly on each rung. Wear footwear with heels. Ensure that footwear is in good condition. Clean muddy or slippery boot soles before mounting a ladder. Rise or lower tools and materials using a hand-line.

2(o)(6) Ladder Inspections123 Inspect any ladder for: • • • • • • • • • • • • • •

missing or loose steps or rungs (they are loose if you can move them by hand); damaged or worn non-slip feet; loose nails, screws, bolts or nuts; loose or faulty spreaders, locks, and other metal parts in poor repair; rot, decay or warped rails in wooden ladders; cracks and exposed fiberglass in fiberglass ladders; cracked, split, worn or broken rails, braces, steps or rungs; sharp edges on rails and rungs; rough or splintered surfaces; corrosion, rust, oxidization and excessive wear, especially on treads twisted or distorted rails; distortion by sighting along the rails; wobble; loose or bent hinges and hinge spreaders; and broken stop on a hinge spreader.

Inspect extension ladders for: • • • • • 122

loose, broken or missing extension locks; defective locks that do not seat properly when ladder is extended; sufficient lubrication of working parts; defective cords, chains and ropes; and missing or defective pads or sleeves.

U.S. Occupational Safety and Health Administration, 29 CFR 3124-12R, 2003. http://www.osha.gov/Publications/osha3124.pdf. 123 Ibid.

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After inspecting any ladder: • • • • • •

Tag any defective ladders and take them out of service; Clean fiberglass ladders every three months; Spray lightly with a clear lacquer or paste wax; Protect wooden ladders with a clear sealer or wood preservative; Replace worn or frayed ropes on extension ladders; and Lubricate pulleys on extension ladders regularly.

2(o)(7) Bibliography Nigerian Safety Council, Job Made Ladders, Data Sheet No. 1-568-76, 1976. Nigerian Safety Council, Accident Prevention Manual for Industrial Operations, Ninth Edition, 1988. U.S. Occupational Safety and Health Administration, 29 CFR 3124-12R, 2003. http://www.osha.gov/Publications/osha3124.pdf.

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SEC. 2(p) FORKLIFT SAFETY CONTENTS 2(p)(1) Introduction ..............................................................................................................II-343 2(p)(2) Pre-Qualifications for Forklift Operators..............................................................II-343 2(p)(3) Safe Operating Procedures......................................................................................II-343 2(p)(4) Changing and Charging Storage Batteries ............................................................II-344 2(p)(5) Operations.................................................................................................................II-344 2(p)(6) Traveling ...................................................................................................................II-345 2(p)(7) Loading......................................................................................................................II-345 2(p)(8) Fueling .......................................................................................................................II-345 2(p)(9) Maintenance..............................................................................................................II-346 2(p)(10) Training...................................................................................................................II-346 2(p)(11) Refresher Training and Evaluation......................................................................II-347 2(p)(12) Bibliography ...........................................................................................................II-348

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2(p)(1) Introduction Appropriate procedures and caution are necessary to avoid personal injury during the movement of products and materials via a forklift or power industrial truck. 2(p)(2) Pre-Qualifications for Forklift Operators124 Forklift training prerequisites: • • • • • •

Driver's license and good driving record. No vision problems that cannot be rectified by glasses or contacts. No hearing loss that cannot be rectified by a hearing aid. No physical disabilities that would impair safe operation. No neurological disorders that may affect balance or consciousness. No medication can be taken that affects perception, vision, or physical abilities.

2(p)(3) Safe Operating Procedures125 • • • • • • • • • • • • • • • •

Only authorized and trained personnel should operate powered industrial trucks. Powered industrial trucks must contain a headache rack, fire extinguisher, rotating beacon, back-up alarm, and seat belts. Seatbelts must be worn by operators at all times. Inspections must be conducted by operators. Report safety defects immediately, and repair or remove the powered industrial truck removed from service. Proper recharging/refueling safety procedures must be followed. Operators must wear hard hats where overhead hazards exist. Sound the horn and use extreme caution when around pedestrians, making turns, and cornering. Prohibit passengers from riding on any portion of a powered industrial truck. Use a suitable man lift platform that is attached to the mast if powered industrial trucks are used to elevate a person. The path of the vehicle must be free from obstructions, aisles must be marked, and wide enough (minimum of 1.83 meters). Clearly mark the lift capacity on the industrial power truck, and the load should not exceed that weight limit. A multi-purpose dry chemical fire extinguisher must be present in all powered industrial trucks (with the exception of pallet jacks). Report all accidents to a Supervisor. Follow proper docking/undocking procedures, and rail cars and trailers should parked “squarely” to the loading area and the wheels locked in place. Changes must be approved by the manufacturer. The new rated load capacities established and posted on the truck, and written approval is necessary.

124

U.S. Department of the Interior, Occupational Health and Medical Services. http://medical.smis.doi.gov/FORKLIFT.html. 125 Southern Methodist University, Risk Management and Environmental Health. & Safety Procedure, March 2004.

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2(p)(4) Changing and Charging Storage Batteries126 • • • • • • • • • • • •

Place battery charging installations in designated areas. Provide facilities for flushing and neutralizing spilled electrolyte, fire protection, protecting charging equipment from damage by trucks, and for ventilation for diffusion of fumes from gassing batteries. Use a provided conveyor, overhead hoist, or equivalent equipment when handling batteries. Reinstalled batteries must be correctly positioned and secured in the truck. Handled electrolytes by using a provided carbon filter or siphon. Pour acid into water when charging a battery. Do not pour water into acid. Before charging or changing the batteries, trucks must be correctly positioned and brakes applied. Ensure that the vent caps are functioning. The battery cover must be open to disperse heat. Smoking is prohibited in the battery charging area. Avoid open flames, sparks, or electric arcs in battery charging areas. Tools and other metallic objects can not be on the top of uncovered batteries.

2(p)(5) Operations127 • • • • • • • • • •

126

Remove a powered industrial truck from service if it is discovered to be defective, or unsafe. Do not drive a truck or forklift up to an individual standing in front of a fixed object. Individuals are prohibited from standing or passing under an elevated portion of a truck. Unauthorized personnel are prohibited from riding on an industrial truck. Passengers may only ride in a truck if there is an extra seat with a seatbelt. Individuals are prohibited from placing their arms or legs between the uprights of the mast or outside the running lines of the truck. When a powered industrial truck is left unattended, the load engaging means must be completely lowered, controls neutralized, power shut off, and brakes set. The wheels of the truck must be blocked if the truck is parked on an incline. Maintain a safe distance from the edge of the ramps or the platforms on any elevated dock, platform, or freight car. The trucks can not be used for opening or closing freight doors. There must be sufficient headroom under overhead installations, lights, pipes, sprinkler system, etc. Use an overhead guard for protection from falling objects. An overhead guard offers protection from impact of small packages, boxes, bagged material, etc. A load backrest extension should be used to decrease the chance of the load or part of it from falling backwards.

Southern Methodist University, Risk Management and Environmental Health. & Safety Procedure, March 2004. U.S. Department of the Interior, Occupational Health and Medical Services. http://medical.smis.doi.gov/FORKLIFT.html. 127

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2(p)(6) Traveling128 • • • • • • • • • • • • •

Observe all traffic regulations, including authorized speed limits and yielding to pedestrians. Maintain a safe distance, approximately three truck lengths from the truck ahead, and keep the truck under control at all times. Yield the right of way to ambulances, fire trucks, or other vehicles in emergency situations. Refrain from passing other trucks traveling in the same direction at intersections, blind spots, or other dangerous locations. Slow down and use the horn at cross aisles and areas where vision is obstructed. Travel with the load trailing is the load carried is obstructing forward view. The loads should be tilted back and raised no more than six inches above the ground. Cross railroad tracks diagonally. Do not park closer than eight feet from the center of the railroad tracks. Look in the direction of the path you are traveling and maintain a clear view ahead. Ascend and descend grades slowly, and position the load uphill in relation to the operator during ascend or descend of grades. Use dock plate when loading rail cars and trailers. Secure dock board or bridge plates before driving them over. Drive dock board or bridge plate slowly and carefully, never exceeding their rated capacity. Be careful not to run over loose objects on the road. During turns, slow down to a safe speed and turn the steering wheel in a smooth motion. When maneuvering at a low speed, turn the steering wheel at a moderate and even rate.

2(p)(7) Loading129 • • • • • •

When possible, handle stable or safely arranged loads that are centered – always use caution when handling loads. Adjust the long or high loads that may affect capacity. Only handle loads within the rated capacity of the truck. Trucks equipped with attachments must be operated as partially loaded trucks when not handling a load. A load engaging means must be placed under the load as far as possible. The mast must be carefully tilted backward to stabilize the load. Use extreme caution when tilting the load forward or backward. Do not tilt an elevated load forward unless when the load is in a depositing position. During stacking or tiering, only tilt enough to stabilize the load.

2(p)(8) Fueling130 • •

Do not fill the fuel tanks while the engine is running. Do not spill.

128

U.S. Department of the Interior, Occupational Health and Medical Services. http://medical.smis.doi.gov/FORKLIFT.html. 129 Southern Methodist University, Risk Management and Environmental Health. & Safety Procedure, March 2004. 130 Ibid.

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Ensure that if oil or fuel spills, it is either washed away or evaporated, and that the fuel tank cap is replaced before starting the engine. Do not operate truck with a leak in the fuel system. Do not use an open flame while checking the electrolyte level in storage batteries or gasoline levels in fuel tanks.

2(p)(9) Maintenance131 • • • • • • • •

All power operated trucks that are unsafe must be removed from service and repaired by authorized personnel. Conduct repairs to the fuel and ignition systems of industrial trucks that involve fire hazards in designated area. Disconnect the battery in trucks when repairing the electric system. Use parts recommended by the manufacturer of the truck or forklift. Examine all industrial trucks prior to placing them in service. Remove the truck if it is deemed unsafe. Examine trucks and forklifts before each shift if it is used round-theclock and correct necessary defects. Remove any truck if its temperature exceeds the normal operating temperature, therefore creating potentially harmful conditions. Only put truck or forklift back in service if the cause of temperature excess is rectified. Keep industrial trucks and forklifts in a clean condition, free of lint, excess oil, and grease. Use noncombustible agents to clean the trucks and forklifts. Low flash point (below 37.8 degrees C) solvents must not be used. High flash point (at or above 37.8 degrees C) solvents may be used.

2(p)(10) Training132 Choose an experienced operator to undergo forklift training. The training occurs under close supervision. Trainees are permitted to operate a powered industrial truck under the following conditions: • •

Under the direct supervision of qualified personnel, who have the knowledge, training, and experience to train operators and evaluate their competence; and Where such operation does not endanger the trainee or other employees.

Training should consist of a combination of formal instruction, practical training (demonstrations performed by the trainer and practical exercises performed by the trainee), and evaluation of the operator's performance in the workplace.

131

Southern Methodist University, Risk Management and Environmental Health. & Safety Procedure, March 2004. U.S. Department of the Interior, Occupational Health and Medical Services. http://medical.smis.doi.gov/FORKLIFT.html. 132

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Initial training for truck/forklift-related and workplace-related topics133 Truck-related topics: • • • • • • • • • • • • •

Operating instructions, warnings, and precautions for the type of truck the operator will be authorized to operate, Differences between the truck and automobiles, Truck controls and instrumentation, Engine or motor operation, Steering and maneuvering, Visibility (including restrictions due to loading), Fork and attachment adaptation, operation, and use limitations, Vehicle capacity, Vehicle stability, Vehicle inspection and maintenance that the operator will be required to perform, Refueling and/or charging and recharging of batteries, Operating limitations, and Operating instructions, warnings, or precautions listed in the operator's manual for the types of vehicle that the employee is being trained to operate.

Workplace-related topics: • • • • • • • • •

Surface conditions where the vehicle will be operated. Composition of loads to be carried and load stability. Load manipulation, stacking, and unstacking. Pedestrian traffic in areas where the vehicle will be operated. Narrow aisles and other restricted places where the vehicle will be operated. Hazardous (classified) locations where the vehicle will be operated. Ramps and other sloped surfaces that would affect the vehicles' stability. Closed environments and other areas where insufficient ventilation or poor vehicle maintenance could cause a buildup of carbon monoxide or diesel exhaust. and Other unique or potentially hazardous environmental conditions in the workplace that could affect safe operation.

2(p)(11) Refresher Training and Evaluation134 Refresher training, including an evaluation of the effectiveness of that training, must be conducted to ensure that the operator has the knowledge and skills needed to operate the powered industrial truck safely. Refresher training in relevant topics must be provided to the operator in the following situations: •

The operator has been observed operating the vehicle in an unsafe manner.

133

Ibid. U.S. Department of the Interior, Occupational Health and Medical Services. http://medical.smis.doi.gov/FORKLIFT.html. 134

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The operator has been involved in an accident or near-miss incident. The operator has received an evaluation that reveals that the operator is not operating the truck safely. The operator is assigned to drive a different type of truck. A condition in the workplace changes in a manner that could affect safe operation of the truck. Once every three years, an evaluation will be conducted of each powered industrial truck operator's performance.

2(p)(12) Bibliography ACT WorkCover, WorkSafe Victoria publications, http://www.workcover.act.gov.au/docs/publications.htm. Southern Methodist University, Risk Management and Environmental Health. & Safety Procedure, March 2004. U.S. Department of the Interior, Occupational Health and Medical Services. http://medical.smis.doi.gov/FORKLIFT.html.

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SEC. 2(q) CRANE OPERATION SAFETY CONTENTS 2(q)(1) Lifting Principles ......................................................................................................II-351 2(q)(2) Operational Considerations.....................................................................................II-352 2(q)(3) Construction Requirements.....................................................................................II-352 2(q)(4) Inspection Guidelines ...............................................................................................II-353 2(q)(4)(i) Preinspection........................................................................................................ II-353 2(q)(4)(ii) Crane Setup......................................................................................................... II-353 2(q)(4)(iii) Electrical Hazards.............................................................................................. II-354 2(q)(4)(iv) Load Charts........................................................................................................ II-354 2(q)(4)(v) Safe Operating Precautions................................................................................. II-354 2(q)(4)(vi) Inspection Types ................................................................................................ II-355 2(q)(4)(vii) Starting the Inspection ...................................................................................... II-357 2(q)(4)(viii) Specific Inspection Items and References ....................................................... II-358 2(q)(5) Definitions .................................................................................................................II-366 2(q)(6) Bibliography..............................................................................................................II-368

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2(q)(1) Lifting Principles There are four basic lifting principles that govern a crane's mobility and safety during lifting operations: 1. Center of Gravity - The center of gravity of any object is the point in the object where its weight can be assumed to be concentrated or, stated in another way, it is the point in the object around which its weight is evenly distributed. The location of the center of gravity of a mobile crane depends primarily on the weight and location of its heaviest components (boom, carrier, upperworks and counterweight). 2. Leverage Cranes use the principle of leverage to lift loads. Rotation of the upperworks (cab, boom, counterweight, and load) changes the location of the crane's center of gravity, its leverage point or fulcrum. As the upperworks rotates, the leverage of a mobile crane fluctuates. This rotation causes the crane's center of gravity to change and causes the distance between the crane's center of gravity and its tipping axis to also change. Stability can be affected by the fluctuating leverage the crane exerts on the load as it swings. The crane's rated capacity is therefore altered in the load chart to compensate for those changes in leverage. Provided the ground is capable of supporting the load, a crane can be made more stable by moving the tipping axis further away from its center of gravity. The extra stability gained by moving the tipping axis can then be used to carry larger/heavier loads. INCREASED STABILITY = MORE LOAD 3. Stability is the relationship of the load weight, angle of the boom and its radius (distance from the cranes center of rotation to the center of load) to the center of gravity of the load. The stability of a crane could also be affected by the support on which the crane is resting. A crane's load rating is generally developed for operations under ideal conditions, i.e., a level firm surface. Unlevel surfaces or soft ground therefore must be avoided. In areas where soft ground poses a support problem for stability, mats and or blocking should be used to distribute a crane's load and maintain a level stable condition. In addition to overturning (stability failure), cranes can fail structurally if overloaded enough. Structural failure may occur before a stability failure. In other words, a mobile crane's structure may fail long before it tips. As loads are added beyond its rated capacity, a crane may fail structurally before there is any sign of tipping. Structural failure is not limited to total fracture; it includes all permanent damage such as overstressing, bending and twisting of any of the components. When a crane is overstressed, the damage may not be apparent. Nevertheless, a structural failure has occurred and overstressed components are then subject to catastrophic failure at some future time. 4. Structural Integrity - The crane's main frame, crawler track and/or outrigger supports, boom sections, and attachments are all considered part of the structural integrity of lifting. In addition, all wire ropes, including stationary supports or attachment points, help

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determine lifting capacity and are part of the overall structural integrity of a crane's lifting capacity. The following elements may also affect structural integrity: a. The load chart capacity in relationship to stability; b. The boom angle limitations which affect stability and capacity; and c. The knowledge of the length of boom and radius in determining capacity. Stability failures are foreseeable, but in structural failure it is almost impossible to predict what component will fail at any given time. No matter what the cause, if the crane is overloaded, structural failure can occur. 2(q)(2) Operational Considerations Cranes are carefully designed, tested, and manufactured for safe operation. When used properly they can provide safe reliable service to lift or move loads. Because cranes have the ability to lift heavy loads to great heights, they also have an increased potential for catastrophic accidents if safe operating practices are not followed. Crane operators and personnel working with cranes need to be knowledgeable of basic crane capacities, limitations, and specific job site restrictions, such as location of overhead electric power lines, unstable soil, or high wind conditions. Personnel working around crane operations also need to be aware of hoisting activities or any job restrictions imposed by crane operations, and ensure job site coordination of cranes. Crane inspectors therefore should become aware of these issues and, prior to starting an inspection, take time to observe the overall crane operations with respect to load capacity, site coordination, and any job site restrictions in effect. 2(q)(3) Construction Requirements Some key requirements are as follows: 1. The employer shall comply with the manufacturer's specifications and limitations applicable to the operation of any and all cranes and derricks. Where manufacturer's specifications are not available, the limitations assigned to the equipment shall be based on the determinations of a qualified engineer competent in this field and such determinations will be appropriately documented and recorded. Attachments used with cranes shall not exceed the capacity, rating, or scope recommended by the manufacturer. 2. Rated load capacities, and recommended operating speeds, special hazard warnings, or instruction, shall be conspicuously posted on all equipment. Instructions or warnings shall be visible to the operator while he is at his control station. 3. The employer shall designate a competent person who shall inspect all machinery and equipment prior to each use, and during use, to make sure it is in safe operating condition. Any deficiencies shall be repaired, or defective parts replaced, before continued use. 4. A thorough, annual inspection of the hoisting machinery shall be made by an authorized and competent person, or by a government or private agency. The employer shall maintain a record of the dates and results of inspections for each hoisting machine and piece of equipment. 5. Except where electrical distribution and transmission lines have been de-energized and visibly grounded at point of work or where insulating barriers, not a part of or an II-352

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attachment to the equipment or machinery, have been erected to prevent physical contact with the lines, equipment or machines shall be operated approximate to power lines only in accordance with the following: a. For lines rated 50 kV or below, minimum clearance between the lines and any part of the crane or load shall be 3.05 meters; b. For lines rated over 50 kV, minimum clearance between the lines and any part of the crane or load shall be 3.05 meters plus 1.02 centimeters for each 1 kV over 50 kV, or twice the length of the line insulator, but never less than 3.05 meters; c. A person shall be designated to observe clearance of the equipment and give timely warning for all operations, where it is difficult for the operator to maintain the desired clearance by visual means; d. Any overhead wire shall be considered to be an energized line unless and until the person owning such line or the electrical utility authorities indicate that it is not an energized line and it has been visibly grounded. 6. No modifications or additions which affect the capacity or safe operation of the equipment shall be made by the employer without the manufacturer's written approval. In no case shall the original safety factor of the equipment be reduced. 2(q)(4) Inspection Guidelines Since cranes impact such a large segment of work going on at any job site, crane inspections must include a survey, or walk around, of the entire operation that questions how the crane will be operating and how other crafts will be effected by working with and around the crane. Observation of crane operations prior to an inspection, or simply asking how cranes have or will be used, can indicate possible problem areas that may need a closer review during the inspection process. 2(q)(4)(i) Preinspection Before the actual inspection, some general information about the crane operator's qualifications and the crane's certifications should be gathered, such as: • •

Operator Qualifications - Observe the operator in action and when the opportunity permits ask a few question concerning the cranes capacity and restrictions imposed, either due to activity involved in or functional limitations. Crane Records - Ask for inspection and maintenance records and verify that the appropriate operator's manual and load charts are available for that particular crane in use.

2(q)(4)(ii) Crane Setup In your initial survey of crane operations, look for crane stability, physical obstructions to movement or operation, and proximity of electrical power lines, as well as the following: 1. Leveling - Has the crane operator set the crane up level and in a position for safe rotation and operation?

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2. Outriggers - Are the outriggers, where applicable, extended and being used in accordance with manufacturer's recommendations? 3. Stability - The relationship of the load weight, angle of boom, and its radius (the distance from the cranes center of rotation to the center of load) to the center of gravity of the load. Also, the condition of crane loading where the load moment acting to overturn the crane is less than the moment of the crane available to resist overturning. 4. Structural Integrity - The crane's main frame, crawler, track and outrigger supports, boom sections, and attachments are all considered part of structural components of lifting. In addition, all wire ropes, including stationary supports, help determine lifting capacity and are part of the structural elements of crane operations. 2(q)(4)(iii) Electrical Hazards Working around or near electrical power lines is one of the most dangerous practices for crane operations. Limit crane operations to a minimum clearance of 3.05 meters. Cranes should not be used to handle materials or loads stored under electric power lines. In addition, operation of mobile cranes near de-energized electric power lines is not recommended until the following steps have been taken: • • • •

The power company or owner of the power line has deenergized the lines. The lines are visibly grounded and appropriately marked at jobsite. Durable warning signs are installed at the operator's station and on the outside of the crane identifying the clearance requirements between the crane/load and electrical power lines. Qualified representatives of the power company or owner of the electrical power line are on the job site to verify that the power lines have been de-energized or properly grounded.

2(q)(4)(iv) Load Charts Load Charts are the principle set of instructions and requirements for boom configurations and parts of line which establish crane capacity for safe crane operations. • •

Availability - The crane operator must have in his/her possession the appropriate load charts related to the crane in use and for the loads being lifted. Correct Use - The crane operator must show adequate understanding and proficient use of the load charts as related to the equipment in use and the loads being lifted.

2(q)(4)(v) Safe Operating Precautions Because cranes have the ability to lift heavy loads to great heights, they also have an increased potential for catastrophic accidents if safe, operating practices are not followed. Accidents can be avoided by careful job planning. The person in charge must have a clear understanding of the work to be performed and consider all potential dangers at the job site. A safety plan must be developed for the job and must be explained to all personnel involved in the lift. II-354

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Before operations begin for the day, a walkaround inspection needs to be conducted to ensure that the machine is in proper working condition. Only qualified and properly designated people shall operate the crane. Regular inspections are important; they provide a means of detecting potential hazards or conditions that could contribute to a sequence of events leading to an accident. Safe, reliable, and the economic operation of lifting equipment, cannot be ensured without regular safety inspections and thorough preventive maintenance programs. A thorough inspection program can forecast maintenance needs or potential equipment failures or malfunctions. The lack of such a program could result in serious deterioration of the equipment which might lead to excessive replacement, or repair charges, as well as an increased potential for accidents. Due to the wide variation of conditions under which a crane may operate, it is impossible for the manufacturer to determine inspection intervals appropriate for every situation. Inspection intervals recommended in manufacturer's publications represent minimum intervals for average operating conditions. More frequent inspection intervals should be required if use and site conditions are severe and warrant it. Inspections are also designed as maintenance checks and/or as a verification that proper repairs or modifications of equipment have been completed which, if not checked could affect capacities as well as personnel safety. Since the initial load rating for cranes was determined and set under ideal conditions, inspections are required by manufacturers to guarantee optimal operating efficiency and capacity as determined by the load charts. The American Nigerian Standards Institute, ANSI B30.5, (1968), and OSHA both require inspections to be divided into two categories: frequent and periodic. In addition to the performance of these regular inspections, equipment is required to be inspected and tested to ensure that it is capable of safe and reliable operation when initially set or placed in service and after any major repairs or any design modification. 2(q)(4)(vi) Inspection Types 1. Frequent Inspections (daily to monthly intervals). Frequent inspections are usually performed at the start of each shift by the operator who walks around the crane looking for defects or problem areas. Components that have a direct bearing on the safety of the crane and whose status can change from day to day with use must be inspected daily, and when possible, observed during operation for any defects that could affect safe operation. To help determine when the crane is safe to operate, daily inspections should be made at the start of each shift. Frequent inspections should include, but are not limited to the following: a. Check that all exposed moving parts are guarded. A removed guard may indicate that a mechanic is still working on part of the crane. b. Visually inspect each component of the crane used in lifting, swinging, or lowering the load or boom for any defects that might result in unsafe operation. c. Inspect all wire rope (including standing ropes), sheaves, drums rigging, hardware, and attachments. Remember, any hook that is deformed or cracked must be removed from service. Hooks with cracks, excessive throat openings of 15%, or hook twists of 10 degrees or more, must be removed from service. d. Check for freedom of rotation of all swivels.

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e. Visually inspect the boom and jib for straightness and any evidence of physical damage, such as cracking, bending, or any other deformation of the welds. Look for corrosion under any attachments that are connected to the chords and lacing. Watch carefully for cracking or flaking of paint. This may indicate fatigue of the metal which often precedes a failure. On lattice booms, look for bent lacing. If they are kinked or bent, the main chord can lose substantial support in that area. When lacing is bent, the ends also tend to draw together which pulls the main chords out of shape. This precaution is especially important on tubular booms where every component must be straight and free from any dents. Do not attempt to straighten these members by hammering or heating them and drawing them out. They must be cut out and replaced with lacing to the manufacturer's specifications, procedures, and approval. f. Inspect tires for cuts, tears, breaks, and proper inflation. g. Visually inspect the crane for fluid leaks, both air and hydraulic. h. Visually check that the crane is properly lubricated. The fuel, lubricating oil, coolant and hydraulic oil reservoirs should be filled to proper levels. i. Check that the crane is equipped with a fully charged fire extinguisher and that the operator knows how to use it. j. Check all functional operating mechanisms such as: sheaves, drums, brakes, locking mechanisms, hooks, the boom, jib, hook rollers brackets, outrigger components, limit switches, safety devices, hydraulic cylinders, instruments, and lights. k. Check the turntable connections for weld cracks and loose or missing bolts. If they are loose, there is a good chance that they have been stretched. l. When checking the outriggers be sure that neither the beams nor the cylinders are distorted. Check that the welds are not cracked and that both the beams and cylinders extend and retract smoothly and hold the load. Check the condition of the floats, and check that they are securely attached. m. Inspect and test all brakes and clutches for proper adjustment and operation. n. Always inspect boom hoist lockout and other operator aids, such as anti-two-block devices (ATB) and load moment indicators (LMI), for proper operation and calibration. o. While the engine is running, check all gauges and warning lights for proper readings and operate all controls to see that they are functioning properly. p. Check for any broken or cracked glass that may affect the view of the operator. 2. Periodic Inspections (1 to 12 month intervals). The periodic inspection procedure is intended to determine the need for repair or replacement of components to keep the machine in proper operating condition. It includes those items listed for daily inspections as well as, but not limited to, structural defects, excessive wear, and hydraulic or air leaks. Inspection records of the inspected crane shall be maintained monthly on critical items in use, such as brakes, crane hooks, and ropes. These inspection records should include, the date of inspection, the signature of the person who performed the inspection, and the serial number, or other identifier. This inspection record should be kept readily available for review. The manufacturer's maintenance and inspection records, forms/checklist, or equivalent should be used.

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1. Inspect the entire crane for structural damage. Be careful to check for distortion or cracks in main frame, outrigger assemblies, and structural attachments of the upperworks to the carrier. 2. Inspect all welded connections for cracks. Inspect the main chords and lacings and other structural items for paint flaking and cracking which may indicate potential failure, as well as for dents, bends, abrasions, and corrosion. Check hydraulic booms for bending, side sway, or droop. 3. Check for deformed, cracked, or corroded members in the load/stress bearing structure. Magnetic particle or other suitable crack detecting inspection should be performed at least once each year by an inspection agency retained by the owner. Inspection reports should be requested and retained in the crane file. 4. Inspect cracked or worn sheaves and drums. 5. Inspect for worn, cracked, or distorted parts such as: pins, bearings, shafts, gears, rollers, locking devices, hook roller brackets, removable outrigger attachments lugs, and welds. 6. Inspect for excessive wear on brake and clutch system parts, linings, pawls, and ratchets. 7. Inspect all indicators, including load and boom angle indicators, for proper operation and calibration. 8. Inspect all power plants for proper operation. 9. Inspect for excessive wear on drive sprockets and/or chain stretch. 10. Inspect for correct action of steering, braking, and locking devices. 11. Check that the counterweight is secure. 12. Check that the identification number is permanently and legibly marked on jibs, blocks, equalizer beams, and all other accessories. 13. Inspect all hydraulic and pneumatic hoses, fittings, and tubing. Any deterioration of any system component should cause the inspector to question whether further use would constitute a safety hazard. Conditions, such as the following, require replacement of the part in question: a. Any evidence of oil or air leaks on the surfaces of flexible hoses or at the point at which the hose in question joins the metal end couplings. b. Any abnormal deformation of the outer covering of hydraulic hose, including any enlargement, local or otherwise. c. Any leakage at connections which cannot be eliminated by normal tightening. d. Any evidence of abrasive wear that could have reduced the pressure retaining capabilities of the hose or tube effected. The cause of the rubbing or abrasion must be immediately eliminated. 2(q)(4)(vii) Starting the Inspection Since most crane inspections begin with a general walkaround and observation of the overall crane set up and operation, followed by a specific inspection of items or components, the following guidelines are presented in that order. The first section addresses the general items and operational considerations when inspecting any type of crane, followed by the specific inspection items for two specific types of cranes; Grove Rough Terrain 45 U.S. Ton (hydraulic) and Manitowoc 4100 150 U.S. Ton Crawler (lattice boom friction) cranes. In general, the following should be considered when inspecting any crane:

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1. Request for and review all inspection and maintenance documents for the crane being inspected, including the crane manufacturer's inspection and maintenance requirements. 2. Conduct a walkaround inspection, paying particular attention to mechanical systems leaks or damage (oil, hydraulic, air) and structural deficiencies. 3. Look at crane cab for properly marked controls, damaged instruments and for properly displayed and legible load charts. 4. Ask the operator, ground crew (riggers), and/or supervisor’s appropriate questions on load charts, rigging and load weight determinations, and capacities. 5. Request the operator to raise and lower the boom/load line, where practical, and inspect, from the cab position, the running line or rope of the main hoist drum and secondary line or jib line. Check brake action and its ability to stop. 6. If practical, request the operator to lower boom to look at the condition of booms sections, lacing, lifting components, anti-two-block devices, jib back stops, and the condition of the hook. 7. Check crane set up and stability of outriggers on hydraulics and/or the effectiveness of cribbing on crawlers. if possible, request that the crane be rotated to check all clearances and overall stability. 2(q)(4)(viii) Specific Inspection Items and References Table 25 identifies the specific inspection items for cranes as well as a brief description and purpose to help the inspector to have a better understanding of what and why the item is being inspected. Table 25. Inspection Items and Description

ITEM DESCRIPTION / PURPOSE (1) Manufacturer's Operating and Maintenance Manufacturer's operating and maintenance Manuals manuals shall accompany all mobile hoisting equipment. These manuals set forth specific inspection, operation and maintenance criteria for each mobile crane and lifting capacity. (2) Guarding All exposed moving parts such as gears, chains, reciprocating or rotating parts are guarded or isolated. (3) Swing Clearance Protection Materials for guarding rear swing area. (4) High-Voltage Warning Sign High-voltage warning signs displaying restrictions and requirements should be installed at the operator's station and at strategic locations on the crane. (5) Boom Stops Shock absorbing or hydraulic type boom stops are installed in a manner to resist boom overturning. (6) Jib Boom Stops Jib stops are restraints to resist overturning. (7) Boom Angle Indicator A boom angle indicator readable for the operator station is installed accurately to indicate boom angle.

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ITEM (8) Boom Hoist Disconnect, Automatic Boom Hoist Shutoff

(9) Two-Blocking Device

(10) Power Controlled Lowering

(11) Leveling Indicating Device (12) Sheaves

(13) Main Hoist and Auxiliary Drums System

Part II: Safety and Best Industry Practices

DESCRIPTION / PURPOSE A boom hoist disconnect safety shutoff or hydraulic relief automatically stops the boom hoist when the boom reaches a predetermined high angle. Cranes with telescoping booms should be equipped with a two-blocking damage prevention feature that has been tested on-site in accordance with manufacturer’s requirements. All cranes hydraulic and fixed boom used to hoist personnel must be equipped with two-blocking devices on all hoistlines intended to be used in the operation. The anti-two blocking device has automatic capabilities for controlling functions that may cause a two-blocking condition. Cranes for use to hoist personnel must be equipped for power controlled lowering operation on all hoistlines. Check clutch, chains, and sprockets for wear. A device or procedure for leveling the crane must be provided. Sheave grooves shall be smooth and free from surface defects, cracks, or worn places that could cause rope damage. Flanges must not be broken, cracked, or chipped. The bottom of the sheave groove must form a close fitting saddle for the rope being used. Lower load blocks must be equipped with close fitting guards. Almost every wire rope installation has one or more sheaves – ranging from traveling blocks with complicated reeving patterns to equalizing sheaves where only minimum rope movement is noticed. Drum crushing is a rope condition sometimes observed which indicates deterioration of the rope. Spooling is that characteristic of a rope which affects how it wraps onto and off a drum. Spoiling is affected by the care and skill with which the first larger of wraps is applied on the drum. Manufacturer's criteria during inspection usually specify: minimum number of wraps to remain on the drum;

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ITEM

(14) Main Boom, Jib Boom, Boom Extension

(15) Load Hooks and Hook Blocks

(16) Hydraulic Hoses Fittings and Tubing

(17) Outriggers

(18) Load Rating Chart

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DESCRIPTION / PURPOSE condition of drum grooves; condition of flanges at the end of drum; rope end attachment; spooling characteristics of rope; and rope condition. Boom jibs, or extensions, must not be cracked or corroded. Bolts and rivets must be tight. Certification that repaired boom members meet manufacturers original design standard shall be documented. Non-certified repaired members shall not be used until recertified. Hooks and blocks must be permanently labeled with rated capacity. Hooks and blocks are counterweighted to the weight of the overhaul line from highest hook position. Hooks must not have cracks or throat openings more than 15% of normal or twisted off center more than 10o from the longitudinal axis. All hooks used to hoist personnel must be equipped with effective positive safety catches especially on hydraulic cranes. Flexible hoses must be sound and show no signs of leaking at the surface or its junction with the metal and couplings. Hoses must not show blistering or abnormal deformation to the outer covering and no leaks at threaded or clamped joints that cannot be eliminated by normal tightening or recommended procedures. There should be no evidence of excessive abrasion or scrubbing on the outer surfaces of hoses, rigid tubing, or hydraulic fittings. Outrigger number, locations, types and type of control are in accordance with manufacturer's specifications. Outriggers are designed and operated to relieve all weight from wheels or tracks within the boundaries of the outriggers. If not, the manufacturer's specifications and operating procedures must be clearly defined. Outriggers must be visible to the operator or a signal person during extension or setting. A durable rating chart(s) with legible letters

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ITEM

(19) Wire Rope

(20) Cab

(21) Braking Systems

Part II: Safety and Best Industry Practices

DESCRIPTION / PURPOSE and figures must be attached to the crane in a location accessible to the operator while at the controls. The rating charts shall contain the following: • A full and complete range of manufacturer's crane loading ratings at all stated operating radii. • Optional equipment on the crane such as outriggers and extra counterweight which effect ratings. • A work area chart for which capacities are listed in the load rating chart, i.e. over side, over rear, over front. • Weights of auxiliary equipment, i.e. load block, jibs, boom extensions. • A clearly distinguishable list of ratings based on structural, hydraulic or other factors rather than stability. • A list of no-load work areas. • A description of hoistline reeving requirements on the chart or in operator's manual. Main hoist and auxiliary wire rope inspection should include examining for broken wires, excess wear, and external damage from crushing, kinking, cutting or corrosion. Contains all crane function controls in addition to mechanical boom angle indicators, electric wipers, dash lights, warning lights and buzzers, fire extinguishers, seat belts, horn, and clear unbroken glass. Truck cranes and self-propelled cranes mounted on rubber-tired chassis or frames must be equipped with a service brake system, secondary stopping emergency brake system and a parking brake system. Unless the owner/operator can show written evidence that such systems were not required by the standards or regulations in force at the date of manufacture and are not available from the manufacturer. The braking systems must have been inspected and tested and found to be in conformance with applicable requirements.

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ITEM

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DESCRIPTION / PURPOSE Crawler cranes are provided with brakes or other locking devices that effectively hold the machine stationary on level grade during the working cycle. The braking system must be capable of stopping and holding the machine on the maximum grade recommended for travel. The brakes or locks are arranged to engage or remain engaged in the event of loss of operating pressure or power. Make sure that the rotation point of a crane gears and rollers are free of damage, wear and properly adjusted and the components are securely locked and free of cracks or damage. The swing locking mechanism must be functional (pawl, pin) and operated in the cab. The counterweight must be approved and installed according to manufacturer's specifications with attachment points secured.

(22) Turntable/Crane Body

(23) Counterweight

Table 26 shows the items that need to be examined for the Grove Rough Terrain 45 U.S. Ton Hydraulic Crane and their corresponding applicable OSHA 29 CFR 1926 and ANSI B30.5 Standards. Table 26. Rough Terrain 45 Ton Hydraulic Crane

STANDARD (29 CFR 1926.550)

INSPECTION ITEMS Outriggers 1. Lubrication 2. Structural Condition 3. Pressure Hoses/Connections Turntable/Crane Body 1. Ensure Level/Stability 2. Wear/Gear/Teeth/Rollers 3. Cracks 4. Bolts/Ensure Securely Attached Counter Weight 1. Proper Size 2. Attachment Connection/Bolts

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ANSI B 30.5 5-1.9.9 5-2.1.3 5-2.1.2

5-1.1 & 5-1.2

5-3.4.2

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STANDARD (29 CFR 1926.550) 1926.550(a)(8) 1926.550(a)(13)(ii) & (iii) ---------1926.550(a)(4) ------------------1926.550(a)(12) ------------------1926.550(a)(14)(i) 1926.550(a)(2) 1926.550(a)(13) & 1926.550(a)(13)(iii)

---------------------------------------------------------------1926.550(b)

Part II: Safety and Best Industry Practices

INSPECTION ITEMS Engine Housing 1. Cleanliness/No Rags/Trash 2. Gear/Machinery Guards 3. Clear Access/Walkways 4. Brakes/Clutch Adjustments 5. Hand Signal Illustration 6. Swing Break Cab 1. Glass/Visibility 2. Instruments and Controls 3. Functioning Horn (Warning signal) 4. Fire Extinguisher 5. Appropriate Load Charts and Warning Signs 6. Proper and Adequate Access (Steps/Walkway) Drum 1. Proper Size and Spoiling of Hoistlines 2. Drum Sides/Shields for cracks 3. Dogs/Pawls/Locking Devices 4. Drum Rotation vs. Control Motion Boom Sections (Boom sections correspond with crane model) 1. 2. 3. Boom Stops 4. 5. Hoist Line Guides/Sheaves 6. 7. 8. Jib Attachment/ Backstops/Belly Slings Sheave System 1. Ensure Hoist Line and Sheave Size Match 2. Worn 3. Lubrication/Move Freely

ANSI B 30.5 5-1.9.6 5-1.8.2 & 3 ---------5-2 (Fig.16) 5-1.4

---------5-5.1.6.1.1 ---------5-3.4.9 5-5.1.1.3 5-1.8.2 & 3

5-1.3.1 & 2

5-2.1.3

5-1.7.4

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STANDARD (29 CFR 1926.550)

1926.550(a)(7) 1926.550(a)(7)(v) --------------------------------------1926.550(a)(9) 1926.550(a)(15)

INSPECTION ITEMS Load/Auxiliary Hook and Block System 1. Sheaves Function Smoothly 2. Hook Rotates Freely/Lubricated 3. Proper Becket 4. Properly Reeved Wire Rope/Hoist Line 1. Overall Condition 2. End Connections 3. Lubrication 4. Clips Safety Devices 1. Anti-Two Block Devices 2. Boom Backstop Devices 3. Swing Radius Warning Devices 4. Job or Site Specific Devices/system (near electric power/personnel hoisting platforms)

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ANSI B 30.5

5-1-7.1-6

5-1.7.6 -------------------

5-1.1.9 5-2 (Fig. 17)

Additional References: 1926.550(a)(1) ---- Crane used in accordance with manufactures specification. 1926.550(a)(5) ---- Inspection: Competent Person. 1926.550(a)(6) ---- Annual Inspection Record. 1926.550(a)(16) ---- No modifications without written approval of manufacturer. Table 27 shows the items that need to be examined for the Manitowoc 4100 150 U.S. Ton Lattice Boom Crawler Crane and their corresponding applicable OSHA 1926 and ANSI B30.5 Standards. Table 27. 150 Ton Lattice Boom Crawler Crane

STANDARD (29 CFR 1926.550)

INSPECTION ITEMS Track Crawler System 1. Lubrication 2. Connection Bolts 3. Drive Chain (slack & wear) Turntable/Crane Body (Upper Works) 1. Assure Level/Stability 2. Wear/Gear/Teeth/Rollers 3. Cracks 4. Bolts/Pins - Assure Securely Attached

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ANSI B 30.5 5-1.9.9 5-2.1.3 5-2.1.2

5-1.1 & 5-1.2

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STANDARD (29 CFR 1926.550)

Part II: Safety and Best Industry Practices

INSPECTION ITEMS Counter Weight 5. Proper Size 6. Attachment Connection/Bolts

Engine Housing 1. Cleanliness/No Rags/Trash 1926.550(a)(8) 2. Gear/Machinery Guards 1926.550(a)(13)(ii) & (iii) 3. Clear Access/Walkways --------4. Brakes/Clutch Adjustments 1926.550(a)(4) 5. Hand Signal Illustration ---------6. Swing Break ----------

1926.550(a)(12) -------------------1926.550(a)(14)(i) 1926.550(a)(2) 1926.550(a)(13) & 1926.550(a)(13)(iii)

----------------------------------------------------------------

Cab 1. Glass/Visibility 2. Instruments and Controls 3. Functioning Horn (warning signal) 4. Fire Extinguisher 5. Appropriate Load Charts and Warning Signs 6. Proper and Adequate Access (steps/walkway) Hoist Drum System 1. Proper Size and Spoiling of Hoistlines 2. Drum Sides/Shields for Cracks 3. Dogs/Pawls/Locking Devices 4. Drum Rotation vs. Control Motion 5. Clutch and Brakes Boom Sections (Boom sections correspond with crane model) 1. Base Section Properly Attached 2. Pin Clearance 3. Boom Lacing/Cord Damage 4. Boom Stops 5. Gantry System A-Frame 6. Hoist Line Guides/Sheaves 7. Boom Section Connection Pins/Keys

ANSI B 30.5 5-3.4.2

5-1.9.6 5-1.8.2 & 3 ---------5-2 (Fig.16) 5-1.4

---------5-5.1.6.1.1 ---------5-3.4.9 5-5.1.1.3 5-1.8.2 & 3

5-1.3.1 & 2

5-2.1.3

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STANDARD (29 CFR 1926.550) 1926.550(b)

1926.550(a)(7) 1926.550(a)(7)(v) ---------------------

------------------1926.550(a)(9) 1926.550(a)(15)

INSPECTION ITEMS 8. Boom and Gantry Support System 9. Jib Attachment/Backstops/Belly Slings (Jib Security Device) Sheave System 1. Ensure Hoistline and Sheave Size Match 2. Worn 3. Lubrication/Move freely Load/Auxiliary Hook and Block System 1. Sheaves Function Smoothly 2. Hook Rotates Freely/Lubricated 3. Proper Becket 4. Properly Reeved Wire Rope/Hoist Line 1. Overall Condition 2. End Connections 3. Lubrication 4. Clips Safety Devices 1. Anti-Two Block Devices 2. Boom Backstop Devices 3. Swing Radius Warning Devices 4. Job or Site Specific Devices/System/Program for work near electric power and use of personnel hoisting platforms)

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ANSI B 30.5

5-1.7.4

5-1-7.1-6

5-1.7.6 -------------------

5-1.1.9 5-2 (Fig. 17)

Additional references: 1926.550(a)(1) ---- Crane used in accordance with manufactures specification. 1926.550(a)(5) ---- Inspection: Competent Person. 1926.550(a)(6) ---- Annual Inspection Record. 1926.550(a)(16) ---- No modifications without written approval from manufacturers. 2(q)(5) Definitions Auxiliary Hoist - A supplemental hoisting unit, usually of lower load rating and higher speed than the main hoist. Axis of Rotation - The vertical axis around which the crane's superstructure rotates.

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Boom - In cranes and derricks usage, an inclined spar, strut, or other long member supporting the hoisting tackle. Also defined as a structural member attached to the revolving superstructure used for guiding and acting as a support for the load. Boom Angle Indicator - An accessory device that measures the angle of the boom base section centerline to horizontal. Boom Stops - A devise used to limit the angle of the boom at its highest position. Brake – A device used for retarding or stopping motion by friction or power means. Block - Sheaves or grooved pulleys in a frame provided with hook, eye, and strap. Crane - A machine consisting of a rotating superstructure for lifting and lowering a load and moving it horizontally on either rubber tires or crawler treads. Counterweight - Weights used for balancing loads and the weight of the crane in providing stability for lifting. Deck - The revolving superstructure or turntable bed. Drum - The spool or cylindrical member around which cables are wound for raising and lowering loads. Gantry - A structural frame work (also known as an A Frame) mounted on the revolving superstructure of the crane to which the boom supporting cables are reeved. Headache Ball - Heavy weight attached above the hook on a single line or whip line to provide sufficient weight to lower the hook when unloaded. Holding Brake - A brake that automatically sets to prevent motion when power is off. Jib - An extension attached to the boom point to provide added boom length for lifting specified loads. Load - The weight of the object being lifted or lowered, including load block, ropes, slings, shackles, and any other ancillary attachment. Load Block - The assembly of the hook or shackles, swivel, sheaves, pins, and frame suspended from the boom point. Main Hoist - Hoist system or boom used for raising and lowering loads up to maximum rated capacity.

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Mechanical Load Brake - An automatic type of friction brake used for controlling loads in the lowering direction. This device requires torque from the motor to lower a load but does not impose additional loads on the motor when lifting a load. Outriggers - Support members attached to the crane's carrier frame which are used to the crane and may be blocked up to increase stability. Pawl - Also known as "dog". It is a gear locking device for positively holding the gears against movement. Pendants - Stationary cables used to support the boom. Radius - The horizontal distance from the axis of rotation of the crane's superstructure to the center of the suspended load. Reeving - The path that a rope takes in adapting itself to all sheaves and drums of a piece of equipment. Running Sheave - Sheaves that rotate as the hook is raised or lowered Superstructure - The rotating frame, gantry and boom or other operating equipment. Test Load - Any load or force, expressed in pounds, used for testing or certifying the limitations within acceptable tolerances of the anticipated load. Two-Block - The condition in which the lower load lock or hook assembly comes in contact with the upper load block or boom point sheave assembly. Quadrant of Operation - The area of operation that the lift is being made in. Usually divided into four quadrants i.e. front, rear and side(s) - left side and right side. 2(q)(6) Bibliography The American Nigerian Standards Institute, ANSI B30.5, 1968. Occupational Safety and Health Administration, Regulations 29 CFR, 1926. American Nigerian Standards Institute, Overhead and Gantry Cranes B30.5 Standards.

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SEC. 2(r) SCAFFOLDS AND OTHER WORK PLATFORMS CONTENTS 2(r)(1) Introduction................................................................................................................... 371 2(r)(2) Scaffold Safety............................................................................................................... 371 2(r)(2)(i) General Safety Guidelines........................................................................................ 371 2(r)(2)(ii) Safe Usage of Non-mobile Welded Frame Scaffolding.......................................... 372 2(r)(2)(iii) Maximum Weight .................................................................................................. 373 2(r)(2)(iv) Other Specs............................................................................................................. 373 2(r)(2)(v) Don’ts for Safe Scaffold Use................................................................................... 374 2(r)(2)(vi) Scaffold Guardrails................................................................................................. 374 2(r)(2)(vii) Scaffold Safety Checklist ...................................................................................... 374 2(r)(2)(viii) Fall Protection ...................................................................................................... 379 2(r)(2)(ix) Additional Guidelines............................................................................................. 380 2(r)(3) Bibliography .................................................................................................................. 380

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2(r)(1) Introduction When scaffolds, conductive tools, or other materials contact overhead power lines (see Figure 12), workers receive serious and often fatal injuries. Data from the U.S. Nigerian Institute of Occupational Safety and Health (NIOSH), Nigerian Traumatic Occupational Fatalities (NTOF) database indicate that nearly 6,500 traumatic work-related deaths occur each year in the United States; an estimated 7% of these fatalities are electrocutions [NIOSH 1991]. The NTOF data base also shows that from 1980 through 1986, at least 25 deaths resulted when workers contacted overhead power lines while erecting or moving scaffolds or while using conductive tools on scaffolds.

Figure 11. Metal scaffold contacting an overhead power line.

A review of the NTOF data has revealed that many occupational groups (e.g., brickmasons, carpenters, painters, construction laborers, and plasterers) as well as the general public are at risk of electrocution because their jobs involve working from scaffolds near overhead power lines [NIOSH 1991]. This section provides safety guidelines for the use of scaffolds and other work platforms. Additional safe work practices and procedures concerning working near overhead powerlines can be found in Sec.(s). 2(r)(2) Scaffold Safety 2(r)(2)(i) General Safety Guidelines No scaffold shall be erected, moved, dismantled, or altered except under the supervision of competent persons. A competent person is defined as one who is capable of identifying existing and predictable hazards in the surroundings or working conditions, and who has the authorization to take prompt corrective action to eliminate them.

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The following are recommended general safe practices: • • • • • • • • •

Provide safe access to get on and off scaffolds and work platforms safely. Use ladders safely. Keep scaffolds and work platforms free of debris. Keep tools and materials as neat as possible on scaffolds and platforms. These practices will help prevent materials from falling and workers from tripping. Erect scaffolds on firm and level foundations. Finished floors will normally support the load for a scaffold or work platform and provide a stable base. Place scaffold legs on firm footing and secure from movement or tipping, especially surfaces on dirt or similar surfaces. Erect and dismantle scaffolds only under the supervision of a competent person. Each scaffold must be capable of supporting its own weight and 4 times the maximum intended load. The competent person must inspect scaffolds before each use. Use manufactured base plates or mud sills made of hardwood or equivalent to level or stabilize the footings. Don't use blocks, bricks, or pieces of lumber.

For Planking: • • •

•

Fully plank a scaffold to provide a full work platform or use manufactured decking. The platform decking and/or scaffold planks must be scaffold grade and must not have any visible defects. Keep the front edge of the platform within 35.56 centimeters of the face of the work. Extend planks or decking material at least 15.24 centimeters over the edges or cleat them to prevent movement. The work platform or planks must not extend more than 30.48 centimeters beyond the end supports to prevent tipping when workers are stepping or working. Be sure that manufactured scaffold planks are the proper size and that the end hooks are attached to the scaffold frame.

2(r)(2)(ii) Safe Usage of Non-mobile Welded Frame Scaffolding The following are important characteristics of a safe Scaffolding Frame: • • • •

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The frame scaffold must be capable of supporting four times the maximum intended load. Using a horizontal frame separation distance of 2.13 meters, the maximum plank extension over the end support shall be no more than 30.48 centimeters if guardrails are not used to block access to the area. On a 10-section wide frame scaffold, the overlap for each plank on top of each other must be 30.48 centimeters. A scaffold five feet wide, 10.67 meters in length and 9.14 meters high with frame spacing of seven feet must have horizontal securement every 6.1 meters and vertical tie-in every 6.1 meters.

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A frame scaffold, three sections high, using a cantilevered outrigger platform, shall use ties, guys, braces, outriggers or scaffold manufacturer’s stabilizer legs or equivalent.

The following are important characteristics of safe Scaffolding Rails: • • • • •

Guardrails are required on welded frame scaffolds that are 3.05 meters high or more. Top rail height shall be at least 91.44 centimeters to a maximum of 114.3 centimeters. Top rail strength must be at least 90.7 kg for welded frame scaffolds. Midrail strength on a welded frame scaffold must be at least 68 kg. Scaffold legs must bear on base plates and these shall rest on either firm foundation or mudsills.

The following are important characteristics of safe Scaffolding Planks: • • •

The space between the scaffold planks must be no more than one inch. The maximum distance permitted between a plank and a frame upright is nine inches. An uncleated scaffold plank must extend over the end support a minimum of six inches.

The following are important characteristics of safe Scaffolding Cross Bracing and Pins: • • •

Cross bracing is acceptable in place of midrails when the "X" is between 50.8 centimeters and 76.2 centimeters above the work surface. Cross bracing is acceptable in place of a top rail when the "X" is between 76.2 centimeters and 121.9 centimeters above the work surface. The purpose of using pins to lock a scaffold vertically together is to prevent uplift. This can occur with a rough terrain forklift grabbing scaffold. Wind, climbing a scaffold or the use of a hoist can also cause it to lift up.

2(r)(2)(iii) Maximum Weight The maximum intended load of a 25.4 centimeters wide, two-inch nominal thickness wood scaffold plank platform with the scaffold frames 2.14 meters apart horizontally is approximately 79.38 kg. 2(r)(2)(iv) Other Specs • • • •

Scaffold platforms above one section high must be provided with safe access. When hook-on-ladders are used, they must be provided with a rest platform every 10.67 meters. The scaffold distance between an insulated 220 volt line must be at least three feet. Work shall not be permitted during high winds. High winds are classified by the Nigerian Weather Service as 48.28 km/h gusts or higher. Ultimately, the decision is to be made by the competent person.

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safety or fire. Compliance with these recommendations does not ensure the absolute safety of your occupation or place of business. It is the property owner’s duty to warn any tenants or occupants of the property of any safety hazards that may exist. 2(r)(2)(v) Don’ts for Safe Scaffold Use • • • • • • • • • • • • •

DO NOT use damaged parts that affect the strength of the scaffold. DO NOT allow employees to work on scaffolds when they are feeling weak, sick, or dizzy. DO NOT work from any part of the scaffold other than the platform. DO NOT alter the scaffold. DO NOT move a scaffold horizontally while workers are on it, unless it is a mobile scaffold and the proper procedures are followed. DO NOT allow employees to work on scaffolds covered with snow, ice, or other slippery materials. DO NOT erect, use, alter, or move scaffolds within 3.05 meters of overhead power lines. DO NOT use shore or lean-to scaffolds. DO NOT swing loads near or on scaffolds unless you use a tag line. DO NOT work on scaffolds in bad weather or high winds unless the competent person decides that doing so is safe. DO NOT use ladders, boxes, barrels, or other makeshift contraptions to raise your work height. DO NOT let extra material build up on the platforms. DO NOT put more weight on a scaffold than it is designed to hold.

2(r)(2)(vi) Scaffold Guardrails • • •

Guard scaffold platforms that are more than 3.05 meters above the ground or floor surface with a standard guardrail. If guardrails are not practical, use other fall protection devices such as safety harnesses and lanyards. Place the top-rail approximately 106.68 centimeters above the work platform or planking with a mid-rail about half that high at 53.34 centimeters. Install toe boards when other workers are below the scaffold.

2(r)(2)(vii) Scaffold Safety Checklist For Set Up and Use, ask the following questions: • • • • • •

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Is the scaffold being erected under the direction of a competent person? Are all employees involved with (or near) the scaffold wearing hard hats? Are footings sound and rigid - not set on soft ground, frozen ground (that could melt), or resting on blocks? Is the scaffold level? Are wheels/castors locked? Is the scaffold able to hold four times its maximum intended load?

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Is the platform complete front to back and side to side (fully planked or decked, with no gaps greater than 2.54 centimeters)? Are guardrails and toeboards in place on all open sides? Are all sections pinned or appropriately secured? Is there a safe way to get on and off the scaffold, such as a ladder (without climbing on crossbraces)? Is the front face within 35.56 centimeters of the work (or within 91.44 centimeters for outrigger scaffolds)? Does the scaffold meet electrical safety clearance distances? Is the scaffold inspected by a competent person before being put in use? If the scaffold is over 3.05 meters, is personal fall protection provided, or are guardrails over 96.52 centimeters high? Are hardhats worn by workers on and around the scaffold? Are scaffold loads (including tools and other equipment) kept to a minimum and removed when the scaffold is not in use (like at the end of a day)? Are employees removed from scaffolds during high winds, rain, snow, or bad weather? Are materials secured before moving a scaffold? Are employees removed from the scaffold before they are moved? Are heavy tools, equipment, and supplies hoisted up (rather than carried up by hand)?

It is critical that workers understand that serious injury or death can result from failure to familiarize oneself, and comply with all applicable NERC safety guidelines before erecting, using or dismantling this scaffold. The following checklist has been compiled to assist site supervisors: Prior to Erection-All Scaffold Assemblies: •

•

• • •

•

Job site should be inspected to determine ground conditions or strength of supporting structure, and for proximity of electric power lines, overhead obstructions, wind conditions, and the need for overhead protection or weather protection coverings. These conditions must be evaluated and adequately provided for. Frame spacing and mud sill size can only be determined after the total loads to be imposed on the scaffold and the strength of the supporting soil or structure are calculated and considered. This analysis must be done by a qualified person. Load carrying information on components is available from the manufacturer. Stationary scaffolds over 38.1 meters in height and rolling scaffolds over 18.29 meters in height must be designed by a professional engineer. All equipment must be inspected to see that it is in good condition and is serviceable. Damaged or deteriorated equipment should not be used. Wood plank should be inspected to see that it is graded for scaffold use, is sound and in good condition, straight grained, free from saw cuts, splits and holes. (Not all species and grades of lumber can be used as scaffold plank. Wood planks used for scaffolding must be specifically graded for scaffold use by an approved grading agency). The scaffold assembly must be designed to comply with local, State and Federal safety requirements.

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For Erection of Fixed Scaffold the site supervisor shall use the following safety checklist: •

•

• • •

• •

• • • • • •

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Scaffold must be erected, moved, or disassembled only under the supervision of qualified persons. Hard hats must be worn by all persons erecting, moving, dismantling or using scaffolding. Mud sills must be adequate size to distribute the loads on the scaffolding to the soil or supporting structure. Special care is needed when Figure 12. Scaffolding and mud sills scaffolding is to be erected on fill or other soft ground or on frozen ground. Sills should be level and in full contact with the supporting surface. Base plates or screwjacks with base plates must be in firm contact with both the sills and the legs of the scaffolding. Compensate for uneven ground with screwjacks with base plates. DO NOT USE unstable objects such as blocks, loose bricks, etc. Plumb and level scaffold until connections can be made with ease. Do not force members to fit. Be sure scaffold stays level and plumb as erection progresses. Ties, guys, bracing and/or outriggers may be needed to assure a safe stable scaffold assembly. The height of the scaffold in relation to the minimum base width, wind loads, the use of brackets or cantilevered platforms and imposed scaffold loads determines the need for stability bracing. The following general guides are minimum requirements. Scaffolding must always be secure when the height of the scaffold exceeds four (4) times the minimum base width. The bottom tie must be placed no higher than four (4) times the minimum base width and every 7.92 meters vertically thereafter. Ties should be placed as close to the top of the scaffold as possible and, in no case, less than four (4) times the minimum base width of the scaffold from the top. Vertical ties should be placed at the ends of scaffold runs and at no more than 9.14 meters horizontal intervals in between. Ties should be installed as the erection progresses and not removed until the scaffold is dismantled to that height. Side brackets, cantilevered platforms, pulleys or hoist arms and wind conditions introduce overturning and uplift forces that must be considered and compensated for. These assemblies may require additional bracing, tieing or guying. Circular scaffolds erected completely around or within a structure may be restrained from tipping by the use of "stand off" bracing members. Each leg of a free standing tower must be guyed at the intervals outlined above or otherwise restrained to prevent tipping or overturning. Work platforms must be fully planked either with scaffold graded solid sawn or laminated plank, in good sound condition, or with fabricated platforms in good condition.

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• • • •

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Each plank must overlap the support by a minimum of 15.24 centimeters or be cleated, i.e. 2.44 meters planks on 2.13 meter spans must be cleated. Plank should not extend beyond the support by more than 45.72 centimeters. Such overhangs should be separated from the work platform by guard-railing so that they cannot be walked on. Plank on continuous runs must extend over the supports and overlap each other by at least 30.48 centimeters. Spans of full thickness, 5.08 centimeters by 25.4 centimeters scaffold grade planks, should never exceed 3.05 meters. Loads on plank should be evenly distributed and not exceed the allowable loads for the type of plank being used. No more than one person should stand on an individual plank at one time. Planks and/or platforms should be secured to scaffolding when necessary to prevent uplift of displacement because of high winds or other job conditions. Guardrails must be used on all open sides and ends of scaffold platforms. Both top and midrails are required. Local codes specify the minimum heights where guardrails are required, however, use at lower heights if falls can cause injury. Toeboards are required whenever people are required to work or pass under or around the scaffold platform. Access must be provided to all work platforms. If it is not available from the structure, access ladders, frames with built-in ladders, or stairways must be provided. When frames with built-in ladders are used, cleated plank or fabricated plank must be used at platform levels to minimize or eliminate platform overhang. Access ladders must extend at least 91.44 centimeters above platforms. Side and end brackets are designed to support people only. Materials should never be placed on cantilevered platforms unless the assembly has been designed to support material loads by a qualified person. (These types of platforms cause overturning and uplift forces which must be compensated for. All frames should be fastened together to prevent uplift an overturning moment compensated for with counterweights or adequate ties). Putlogs must never be used for the storage of materials. They are designed for personnel use only. Special care should be taken when putlogs are used. Putlogs should overhang the support points by at least 15.24 centimeters. Use putlogs hangers with bolts fastened to support putlogs on frames. Putlog spans of greater than 3.66 meters require kneebracing and lateral support. Putlogs used as side or end brackets need special bracing. Bridging between towers should not be done with plank or stages unless the assembly is designed by a qualified person and overturning moments have been compensated for. Scaffold should not be used as material hoist towers or for mounting derricks unless the assembly is designed by a qualified person. Check the erected assembly before use. A qualified person should thoroughly inspect the completed assembly to see that is complies with all safety codes, that nuts and bolts are tightened, that it is level and plumb, that work platforms are fully planked, that guardrails are in place and safe access is provided.

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For Erection of Rolling Scaffolds the site supervisor shall use the following safety checklist: •

•

• • • • •

Height of the tower must not exceed four (4) times the minimum base dimension (three (3) times in California). Outrigger frames or outrigger units on both sides of the tower may be used to increase base width dimension when necessary. All casters must be secured to frame legs or screwjacks with a nut and bolt or other secure means. Total weight of Figure 13. Scaffolding erected at a contstruction site tower should not exceed the capacity of the casters. Screwjacks must not be extended more than 30.48 centimeters above caster base. Tower must be kept level and plumb at all times. Horizontal/diagonal bracing must be used at the bottom and top of tower and at intermediate levels of 6.1 meters. Fabricated planks with hooks may replace the top diagonal brace. All frames must be fully cross-braced. Only prefabricated plank or cleated plank should be used. Casters must be locked at all times the scaffold is not being moved.

In the Use of All Scaffolds the site supervisor shall use the following safety checklist: •

• • • • • • • • •

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Inspect the scaffold assembly before each use to see that it is assembled correctly, that it is level and plumb, base plates are in firm contact with sills, bracing is in place and connected, platforms are fully planked, guardrails in place, safe access is provided, that it is properly tied and/or guyed and that there are no overhead obstructions or electric lines within 3.66 meters of the scaffold assembly. Use only the safe means of access that is provided. Do not climb bracing or frames not specifically designed for climbing. If such access is not provided, insist that it be provided. Climb Safely. Face the rungs as you climb up or down. Use both hands. Do not try to carry materials while you climb. Be sure of your footing and balance before you let go with your hands. Keep one hand firmly on frame or ladder at all times. Do not work on slippery rungs to avoid slipping. Do not overload platforms with materials. Working heights should not be extended by planking guardrails or by use of boxes or ladders on scaffold platforms.

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Do not remove any component of a completed scaffold assembly except under the supervision of a qualified person. Any component that has been removed should be immediately replaced.

For Rolling Towers All of the above precautions should be checked plus: • • • • • • • • •

Do not ride manually propelled rolling scaffold. No personnel should be on the tower while it is being moved. Lock all casters before getting on the tower. Work only within the platform area: do not try to extend overhead work area by reaching out over guardrailing. Do not bridge between two rolling towers with plank or stages. Secure all materials before moving scaffolds. Be sure floor surface is clear of obstructions or holes before moving scaffold. Be sure there are no overhead obstructions or electric power lines in the path of rolling scaffold. Rolling towers must only be used on level surfaces. Move rolling towers by pushing at the base level only. Do not pull from the top.

2(r)(2)(viii) Fall Protection When dealing with Floor and Wall Openings: • • • •

Install guardrails around openings in floors and across openings in walls when the fall distance is 1.22 meters or more. Be sure the top rails can withstand a 90.72 kg load. Construct guardrails with a top rail approximately 1.07 meters high with a mid-rail about half that high at 53.34 centimeters. Install toe boards when other workers are to be below the work area. Cover floor openings and holes or protect the area with guardrails.

When Working on Roofs: • • • • • •

Inspect for and remove frost and other slipping hazards before getting onto roof surfaces. Cover and secure all skylights and openings, or install guardrails to keep workers from falling through the openings. Fall protection is required when working at heights at or above 3.05 meters and when working on walking working surfaces at or above 1.22 meters. Stop roofing operations when storms, high winds or other adverse weather conditions create unsafe conditions. Remove or properly guard any impalement hazards. Wear shoes with slip-resistant soles.

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2(r)(2)(ix) Additional Guidelines • •

Wear proper slip-resistant shoes or footwear to lessen slipping hazards. Train workers in safe work practices before performing work on foundation walls, roofs, trusses, or before they perform exterior wall erections and floor installations.

2(r)(3) Bibliography U.S. National Institute of Occupational Safety and Health (NIOSH), National Traumatic Occupational Fatalities (NTOF) database, 1991.

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SEC. 2(s) SAFE WORK PRACTICES NEAR POWER LINES CONTENTS 2(s)(1) Introduction...............................................................................................................II-383 2(s)(2) Plan Ahead.................................................................................................................II-383 2(s)(3) Safe Work Practices..................................................................................................II-383 2(s)(3)(i) General ................................................................................................................. II-383 2(s)(2)(ii) Safe Operations of Cranes................................................................................... II-384 2(s)(3)(iii) Procedures to Follow if Contact Occurs ............................................................ II-386 2(s)(3)(iv) Recommended Practices .................................................................................... II-386 2(s)(3)(v) Tree Spraying ...................................................................................................... II-387 2(s)(3)(vi) Electrical Emergencies....................................................................................... II-387 2(s)(3)(vii) Training Workers .............................................................................................. II-388 2(s)(4) Bibliography ..............................................................................................................II-388

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2(s)(1) Introduction Trees and electricity are both beneficial, but when the two come together, problems arise. Add a third element, a human, and a life may be in jeopardy. Workers pruning trees near energized power lines face serious hazards from contact with those lines or related equipment. A worker's body may come into direct contact with an energized line. Tools or other conductive material, such as severed tree limbs, may touch the lines, resulting in an indirect, but equally dangerous, contact. Either way, people are exposed to electrical shock by becoming a path to the ground between an energized conductor and grounded equipment, tools or trees - or by becoming a path between two conductors. The electrical current passing through the body can cause third degree burns, irregular heart action or stoppage, or the stoppage of breathing. In addition, you may be exposed to thermal burns or flash burns from arcing. If you're a tree worker, your first concern should be to protect yourself from such hazards. 2(s)(2) Plan Ahead Before any work begins, the job site should be inspected to locate overhead power lines and electrical equipment. If there appears to be any conflict, contact the electric utility company so measures can be taken to ensure a safe work environment. Remember, the distance the tree is away from the energized lines can be deceiving. In some cases, it may be just as dangerous to trim a tree 3.05 to 6.1 meters from energized lines, as it is to trim one much closer, because a long, large branch can fall into the lines and conduct electricity back to the trimmer who believes he has maintained more than adequate clearance. Unqualified individuals should never trim trees around energized lines. Where electrical hazards exist, only qualified line clearance tree trimmers should do the work. Climb the side of the tree away from any powerlines: the crotch of the tree selected for tying in should be over the work area, but located in such a way that a slip or fall would swing away from energized lines. Ladders and aerial equipment, including insulated aerial equipment, should not be placed in contact with electrical conductors. If an aerial device does contact an electrical line or conductor, the truck supporting the device and any other attached equipment should be considered energized. Anyone touching the equipment could be injured or even killed. 2(s)(3) Safe Work Practices 2(s)(3)(i) General Determine whether you and your crews can maintain the 3.05 meter clearance from power lines. If the line exceeds 50,000 volts, clearance requirements increase. Mechanized equipment must maintain a minimum 3.05 meter distance from powerlines and conductors rated at 50,000 volts or less. The equipment includes load, cables, tag lines and any other attachments. If the powerline is rated more than 50,000 volts, the clearance requirement exceeds 3.05 meters. II-383

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Consider these clearance requirements for work near overhead powerlines as your "circle of safety." These working clearances are minimum safety clearances. Whenever possible, even greater clearances should be maintained. If your work is going to bring you closer than the above clearances allow, notify the electric utility company promptly. No work should be performed near energized conductors until danger of contact with those conductors has been effectively guarded against. Inspect the work site carefully prior to climbing or working on a tree to determine whether electrical lines pass through the tree or within your reach or that of other workers. All lines on utility poles should be viewed as possibly being energized, whether you think they are cable or telephone lines. Branches hanging on energized powerlines should be removed only by qualified line clearance tree trimmers in the employ of the electric utility company and using approved insulated equipment. 2(s)(3)(ii) Safe Operations of Cranes Electrocutions of crane operators and crew members working near overhead power lines is a serious problem. Workers are killed each year when cranes contact overhead power lines. Employers, supervisors, and workers may not be fully aware of the hazards of operating cranes near overhead power lines or may not implement the proper safety procedures for controlling these hazards. Data from the Nigerian Institute for Occupational Safety and Health (NIOSH) Nigerian Traumatic Occupational Fatalities (NTOF) Surveillance System indicate that electrocutions accounted for approximately 450 (7%) of the 6,400 work-related deaths from injury that occurred annually in the United States during the period 1980-89 [NIOSH 1993a]. Each year an average of 15 electrocutions were caused by contact between cranes or similar boomed vehicles and energized, overhead power lines. The actual number of workers who died from crane contact with energized power lines is higher than reported by NTOF because methods for collecting and reporting these data tend to underestimate the total number of deaths [NIOSH 1993a]. A study conducted by the U.S. Occupational Safety and Health Administration (OSHA) showed that 377 (65%) of 580 work-related electrocutions occurred in the construction industry during the period 1985-89 [OSHA 1990]. Nearly 30% (113) of these electrocutions involved cranes. Employers should take precautions when cranes and boomed vehicles are operated near overhead power lines (Figure 15). Any overhead power line should be considered energized unless the owner of the line or the II-384

Figure 14. Improper operation of boomed vehihcle near powerlines

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electric utility company indicates that it has been de-energized and it is visibly grounded. The following are recommended regulations which are based on OSHA standards: •

• •

Employers shall ensure that overhead power lines are de-energized or separated from the crane and its load by implementing one or more of the following procedures: – De-energize and visibly ground electrical distribution and transmission lines. – Use independent insulated barriers to prevent physical contact with the power lines. – Maintain minimum clearance between energized power lines and the crane and its load. Where it is difficult for the crane operator to maintain clearance by visual means, a person shall be designated to observe the clearance between the energized power lines and the crane and its load. The use of cage-type boom guards, insulating links, or proximity warning devices shall not alter the need to follow required precautions. These devices are not a substitute for de-energizing and grounding lines or maintaining safe line clearances.

The American Nigerian Standards Institute (ANSI) has published a standard for mobile and locomotive cranes that includes operation near overhead power lines [ANSI 1994]. This consensus standard (B30.5-1994) contains guidelines for preventing contact between cranes and electrical energy. The standard addresses the following issues: • • • • •

Considering any overhead wire to be energized unless and until the person owning the line or the utility authorities verify that the line is not energized. De-energizing power lines before work begins, erecting insulated barriers to prevent physical contact with the energized lines, or maintaining safe clearance between the energized lines and boomed equipment. Limitations of cage-type boom guards, insulating links, and proximity warning devices. Notifying line owners before work is performed near power lines. Posting warnings on cranes cautioning the operators to maintain safe clearance between energized power lines and their equipment.

The Construction Safety Association of Ontario, Canada (CSA) recommends safe work practices in addition to those addressed in the OSHA and ANSI standards [CSA 1982]. These recommendations include the following: • • • • • •

Operate the crane at a slower-than-normal rate in the vicinity of power lines. Exercise caution near long spans of overhead power lines, since wind can cause the power lines to sway laterally and reduce the clearance between the crane and the power line. Mark safe routes where cranes must repeatedly travel beneath power lines. Exercise caution when traveling over uneven ground that could cause the crane to weave or bob into power lines. Keep all personnel well away from the crane whenever it is close to power lines. Prohibit persons from touching the crane or its load until a signal person indicates that it is safe to do so. II-385

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2(s)(3)(iii) Procedures to Follow if Contact Occurs To protect against electrical shock injury in the event of contact between a crane and an energized line, the CSA recommends the following: • • • •

The crane operator should remain inside the cab. All other personnel should keep away from the crane, ropes, and load, since the ground around the machine might be energized. The crane operator should try to remove the crane from contact by moving it in the reverse direction from that which caused the contact. If the crane cannot be moved away from contact, the operator should remain inside cab until the lines have been de-energized.

2(s)(3)(iv) Recommended Practices Employers should comply with NERC recommended standards and take the following measures to protect workers and operators of cranes and other boomed vehicles from contacting energized overhead power lines. •

•

• • •

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Train workers to comply with the recommended standards. These regulations require workers and employers to consider all overhead power lines to be energized until (1) the owner of the lines or the electric utility indicates that they are not energized, and (2) they have been visibly grounded. Employers shall ensure that overhead power lines are de-energized or separated from the crane and its load by implementing one or more of the following: – De-energize and visibly ground electrical distribution and transmission lines at the point of work. – Use insulated barriers that are not a part of the crane to prevent contact with the lines. – If the power lines are not de-energized, operate cranes in the area ONLY if a safe minimum clearance is maintained as follows:  At least 3.05 meters for lines rated 50 kilovolts or below,  At least 3.05 meters plus 10.2 milimeters for each kilovolt above 50 kilovolts; or maintain twice the length of the line insulator (but never less than 3.05m). Where it is difficult for the crane operator to maintain safe clearance by visual means, designate a person to observe the clearance and to give immediate warning when the crane approaches the limits of safe clearance. Do not use cage-type boom guards, insulating links, or proximity warning devices as a substitute for de-energizing and grounding lines or maintaining safe clearance. Follow ANSI Guidelines - Train workers to follow ANSI guidelines for operating cranes near overhead power lines (ANSI Standard B30.5-1994, 5-3.4.5)[ANSI 1994]. These guidelines recommend posting signs at the operator's station and on the outside of the crane warning that electrocution may occur if workers do not maintain safe minimum clearance that equals or exceeds OSHA requirements shown in Table 28:

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Table 28. OSHA Requirements for Safe Minimum Clearance

Power line voltage phase to phase (kV) 50 or below Above 50 to 200 Above 200 to 350 Above 350 to 500 Above 500 to 750 Above 750 to 1,000 •

• • •

•

Minimum safe clearance (meters) 3.1 4.6 6.1 7.6 10.7 13.7

Notify Power Line Owners - Before beginning operations near electrical lines, notify the owners of the lines or their authorized representatives and provide them with all pertinent information: type of equipment (including length of boom) and date, time, and type of work involved. Request the cooperation of the owner to de-energize and ground the lines or to help provide insulated barriers. NIOSH encourages employers to consider deenergization (where possible) as the primary means of preventing injury from contact between cranes and power lines. Develop Safety Programs - Develop and implement written safety programs to help workers recognize and control the hazards of crane contact with overhead power lines. Evaluate Jobsites - Evaluate jobsites before beginning work to determine the safest areas for material storage, the best placement for machinery during operations, and the size and type of machinery to be used. Know the location and voltage of all overhead power lines at the jobsite before operating or working with any crane. Research has shown that it is difficult to judge accurately the distance to an overhead object such as a power line [Middendorf 1978]. Therefore, NIOSH recommends that no other duties or responsibilities be assigned when workers are designated to observe clearance during crane movement or operation. Evaluate Alternative Work Methods - Evaluate alternative work methods that do not require the use of cranes. For example, it may be possible to use concrete pumping trucks instead of crane-suspended buckets for placing concrete near overhead power lines. Alternative methods should be carefully evaluated to ensure that they do not introduce new hazards into the workplace.

2(s)(3)(v) Tree Spraying Spraying operations near energized electrical wires or equipment may create safety problems. Spraying directed into overheated lines may damage equipment or cause arcing between wires. Electricity also may be conducted down the hose stream, creating a hazard for workers. 2(s)(3)(vi) Electrical Emergencies Strong winds, ice or unintentional contact with equipment may cause trees or tree limbs to fall into powerlines. This may cause wires to break and fall to the ground. Should this happen, notify the electric utility company immediately.

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A fallen wire can create hazards for workers and the general public. Objects touched by a fallen wire - fences, vehicles, buildings or even the surrounding ground - must be considered energized and should not be touched. It is impossible to tell simply by looking whether a downed wire is energized. Consider all downed wires energized and dangerous until the electric utility personnel notify you otherwise. Where a power line has fallen across a vehicle, occupants should remain within the vehicle. If they must leave the vehicle because of a life-threatening situation, such as fire or potential explosion, they should jump clear of the vehicle without touching either the vehicle or wire and the ground at the same time. Once clear of the vehicle, they should shuffle away, taking small steps and keeping both feet in contact with the ground. Remember, electricity can be transmitted from the victim to you. If a switch is accessible, shut off the power immediately. Otherwise, stand on a dry surface and pull the victim away with a dry board or rope. Do not use your hands or anything metal. Use a CO2 or dry chemical extinguisher to put out an electrical fire. Water should be used only by trained firefighting personnel. In an emergency involving power lines or electrical equipment, call the electric utility company immediately. 2(s)(3)(vii) Training Workers Ensure that workers assigned to operate cranes and other boomed vehicles are specifically trained in safe operating procedures. Also ensure that workers are trained (1) to understand the limitations of such devices as boom guards, insulated lines, ground rods, nonconductive links, and proximity warning devices, and (2) to recognize that these devices are not substitutes for deenergizing and grounding lines or maintaining safe clearance. Workers should also be trained to recognize the hazards and use proper techniques when rescuing coworkers or recovering equipment in contact with electrical energy. CSA guidelines list techniques that can be used when equipment contacts energized power lines [CSA 1982]. All employers and workers should be trained in cardiopulmonary resuscitation (CPR). Refer to Sec.2(q) (Crane Operation Safety) for additional safe work practices. 2(s)(4) Bibliography ANSI [1994]. American Nigerian standard for mobile and locomotive cranes. New York, NY: American Nigerian Standards Institute, ANSI B30.5-1994. CFR. Code of Federal regulations. Washington, DC: U.S. Government Printing Office, Office of the Federal Register. CSA (Construction Safety Association) [1982]. Mobile crane manual. Toronto, Ontario, Canada: Construction Safety Association of Ontario.

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Middendorf L [1978]. Judging clearance distances near overhead power lines. In: Proceedings of the Human Factors Society, 22nd annual meeting. Santa Monica, CA: Human Factors Society, Inc. NIOSH [1985]. NIOSH Alert: request for assistance in preventing electrocutions from contact between cranes and power lines. Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, Nigerian Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 85-111. NIOSH [1990a]. Foreman electrocuted and lineman injured after truck-mounted crane boom contacts 7,200-volt overhead power line in Virginia. Morgantown, WV: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, Nigerian Institute for Occupational Safety and Health, Fatal Accident Circumstances and Epidemiology (FACE) Report No. 90-39. NIOSH [1990b]. Laborer touching suspended cement bucket electrocuted when crane cable contacts 7,200-volt power line in North Carolina. Morgantown, WV: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, Nigerian Institute for Occupational Safety and Health, Fatal Accident Circumstances and Epidemiology (FACE) Report No. 90-29. NIOSH [1990c]. Well driller electrocuted when pipe on crane cable contacts 12,000-volt overhead power line in Virginia. Morgantown, WV: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, Nigerian Institute for Occupational Safety and Health, Fatal Accident Circumstances and Epidemiology (FACE) Report No. 90-38. NIOSH [1991]. Construction laborer is electrocuted when crane boom contacts overhead 7,200volt power line in Kentucky. Morgantown, WV: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, Nigerian Institute for Occupational Safety and Health, Fatal Accident Circumstances and Epidemiology (FACE) Report No. 91-21. NIOSH [1993a]. Fatal Injuries to workers in the United States, 1980-1989: a decade of surveillance. Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, Nigerian Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 93-108. NIOSH [1993b]. Truck driver and company president electrocuted after crane boom contacts power line--West Virginia. Morgantown, WV: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, Nigerian Institute for Occupational Safety and Health, Fatality Assessment and Control Evaluation (FACE) Report No. 93-14. OSHA [1990]. Analysis of construction fatalities--the OSHA database 1985-1989. Washington, DC: U.S. Department of Labor, Occupational Safety and Health Administration.

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SEC. 2(t) FUNCTIONAL SAFETY FOR ELECTRIC POWER TRANSMISSION CONTENTS 2(t)(1) Introduction ...............................................................................................................II-393 2(t)(2) Structure of Electric Power Systems .......................................................................II-393 2(t)(3) Hazards in Electric Power Systems .........................................................................II-394 2(t)(3)(i) Hazards in substations .......................................................................................... II-394 2(t)(3)(ii) Security................................................................................................................ II-395 2(t)(4) Assuring Functional Safety ......................................................................................II-397 2(t)(5) Recommended References........................................................................................II-397

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2(t)(1) Introduction This section presents the main types of hazards for personnel, equipment and electric power systems which should be taken into consideration in the design of computer-based systems. An emphasis is put on description of the hazard for safety of an electric power system, whose nature is fundamentally different from the nature of those occurring in the process industry and in all other sectors of industry. To illustrate the problems with hazards and risks identification, a power substation software interlocking case study is described. The case study description is preceded by a short presentation of the results of an extensive review of available publications with the aim of identifying the current state of practice in assuring functional safety of computer systems applied in the sector. Safety as a crucial issue of computer applications in such fields as nuclear power stations, space industry, aircraft industry, chemical industry or railways is well recognized by wide circles of specialists of these fields as well as by specialists in software engineering and computer science. Contemporary electric power systems (EPSs) are very complex and highly technologically advanced systems. The vast, highly interconnected North American electric power system has been called the “greatest machine ever created”. Similarly one could say the same about contemporary electric power systems of other countries. Safety issues are important in designing computer-based control systems for EPSs, which towards the end of the last century emerged as the most critical Nigerian infrastructure in the sense that all other Nigerian critical and vital infrastructures depend on reliable electricity supply. At the same time application of computer-based systems in this sector offers researchers and practitioners a wide range of issues, which are both basic for the future of the sector. 2(t)(2) Structure of Electric Power Systems The electric power industry consists of many different companies involved in generating electric power, bulk transmission of energy from power stations to loading centers and its distribution to customers. In order to perform their functions and to attain suitable effectiveness, all power stations, substations, power lines forming power grids, the related control centers and other components are interconnected, although they belong to various companies, forming an electric power system (EPS). This interconnection is now the strongest at the Nigerian level, forming a Nigerian power system. However an increasing tendency can be observed, for example in Europe, aiming to build up more and more stronger connections between the separate EPS-s existing in the individual countries. Energy related policy of the European Union aims at building Trans-European networks in order to provide a sound basis for free and competitive electricity market in Europe and strengthening security of energy supply. In the most general terms, an EPS can be partitioned into generating stations and high-voltage power networks known as grids. Power networks consist of transmission networks, called extrahigh voltage (EHV) networks, which are used to transmit power from generating stations to main load centres and distribution networks of lower voltages, also known as high-voltage (HV) networks, which are used to transmit power to customers. Both, transmission and distribution networks consist of power lines, substations and control centers.

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Substations form vital nodes in the HV and EHV networks because they make possible modifications in the configuration of networks during the operation of the system by means of switching devices that can be controlled by computer-based control systems applied in the substations. Initiation of the control procedure may be performed locally by substation operators or remotely from the EPS control canters. They also are the points in which power is leaded out of the generation stations and supplied to the consumers. The power network of generation, transmission and distribution subsystems forming an EPS is coupled with telecommunication and telecontrol systems that are used for communication and transmission of data between power generating stations, substations and control centers for remote operation and remote real-time signaling, metering, control and fault protection. Development of these EPS communication systems goes toward an integrated EPS telecommunication network. In the last decade due to the process of computerization of the EPSs the data network is used on increasingly larger scale for transmitting the data that are critical to safe and reliable operation of an EPS and for the power grid - related financial transactions. 2(t)(3) Hazards in Electric Power Systems In an EPS, most hazards connected with current application of computer-based systems concern mainly some applications in power stations, substations and control centers. Most hazards, which appear in power stations and substations, are hazardous for people and equipment and are connected with the technological process of energy production or switching operations performed at substations. Those kinds of hazards are approximate to the kind of hazards appearing in other sectors of industry. Their nature is rather obvious and due to space limitation in this paper they will not be analyzed except of hazards connected with switching operations performed in substations. Further on in this section an emphasis is put on description of concept of safety of an electric power system, whose nature is fundamentally different from the nature of those occurring in the process industry sector and all other sectors of industry. 2(t)(3)(i) Hazards In Substations Electric power substations consist of two essential parts: • •

main (high or extra-high voltage) circuits, also called primary circuits; and auxiliary circuits also called secondary circuits.

Main circuit of a substation is composed of a busbar system (or busbar systems) and connections of power lines, power transformers, etc to the busbar system through switching devices. A busbar system it is set of three electric conductors of very low impedance that serves as a common connection for individual power lines, power transformers, etc. Substations are divided into bays. Bay of a substation it is a part of substation containing high (or extra-high) voltage switching devices and connections of individual power lines, individual power transformers, etc to the substation busbar system (or busbar systems) as well as protection, control, and measurement devices for the individual power line, the individual power transformer, etc. If it is a bay used to

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connect a power line to busbars it is called a line bay, if it is used for connection a power transformer it is called a transformer bay, etc. Normally a substation contains a few or more line and transformer bays and sometimes also other bays. All bays are similar to the line bay. Auxiliary circuits are electrical circuits contain measurement, signaling, control and protection devices. Main hazard for substation staff and equipment is connected with the fact, that for design reasons, disconnectors used in substations are not able to switch on or off the current (e.g. to switch on or off the loaded line) and are used only to ensure the required isolation clearance between disconnected elements which due to design restrictions cannot be achieved by a circuit breaker. In order to take these limitations into consideration switching off a line for example must be performed according to the following sequence: • • •

breaking of the current using a circuit-breaker; opening of the line disconnector in order to achieve isolation clearance between the disconnected line and the circuit-breaker; and opening of the busbar disconnector, depending on which busbars, “1A” or “2”, the line is connected to) in order to achieve the isolation clearance between the circuit-breaker and busbars.

If this sequence is carried out in an incorrect way, and for example the signal for opening would be sent at first to the disconnector (e.g. busbar disconnector), an electric arc will arise between the contacts of the disconnector accompanied by high rate optic and acoustic phenomena, spraying melted metal etc. The arc would travel to neighboring phases, resulting in an interphase short circuit. It would look like an explosion. This failure would cause considerable material losses because of complete destruction of the disconnector and partially or complete destruction also other components in the substation, disturbance in substation operation and interruption of energy supply to consumers. Sprayed melted metal could seriously injure personnel if accidentally someone of the personnel is near an exploding disconnector. Depending on the situation in a given EPS, the incorrect sequence of switching operation could also cause even large power system failure and collapse a part of the EPS, i.e. it could create a hazard for the described below safety of the EPS. Note that in high voltage networks transmission lines have three wires, one for each phase. It concerns also busbar systems in substations. Each busbar system in a substation consist of three bars. 2(t)(3)(ii) Security In electric power systems engineering safety of an EPS is described by means of the word “security,” although in less formal descriptions the word “safety” is also used. Because in computer science and software engineering the word “security” is used in a different meaning to avoid misunderstanding, the codes refer to the safety of EPS by means of the word “safety” which according to widely accepted definition given by the North American Electric Reliability

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Council (NERC) means the ability of the bulk power electric system to withstand sudden disturbances such as electric short circuits or unanticipated loss of system components. Generally speaking, if all generators connected to an EPS work synchronously and the voltage and the frequency in the EPS is within the required limits, then this is a normal, stable state of an EPS. In case of sudden disturbances, e.g. sudden increase of the load, or switching off an important transmission line due to a failure in a substation computer control or protection system, the stable state of operation is disturbed. Each EPS is designed with a certain stability margin. When the disturbance is greater than the stability margin it results in loss of stability and collapse of the EPS, which may be total, and this is called a black-out, or partial. The loss of stability is understood in the sense applied in dynamical systems, it means generators connected to the EPS fall-out of synchronism. It causes an emergency shutdown of the generators by automatic protection devices in order to protect them against destruction and emergency stop of the power stations. Economic and social results of the loss of stability by an EPS are always very serious and can be catastrophic. This is the reason why maintaining stability of an EPS is the main requirement for the EPS planning, operation and control. Hazard for stability is equivalent to hazard for safety of an EPS. Major blackouts are rare events, but as it has been stated in one publication, their impact can be catastrophic. In fact as it follows from the data published by CIGRE (Conference InterNigeriane des Grands de Reseaux Electriques a Haute Tension) the events are not so rare. A large system failure, which happened in 1977 in New York, blacked out the city and left it without an electricity supply. Losses were estimated at 310 million USDs. The restart of an industrial plant after occurring a power failure with duration time longer than critical one lasts on average 17.4 hours. In the history of the electric utility industry, safety as it is understood today, is a relatively recent concept, which emerged after the famous 1965 blackout that left almost 30 million of people of north-eastern United States and Ontario, Canada, without electricity. Through the first two-thirds of the 20th century, the term ”safety” was not used and the safety of an EPS was subsumed with its reliability and implemented into the system in the system planning process by providing a robust system that could withstand any ”credible” sudden disturbances without a serious disruption. Perhaps the epitome of this approach was mid-century American Electric Power system, which in 1974 withstood five simultaneous major tornadoes, losing eleven 345 kV lines, one 500 kV line, two 765 kV lines, and three major switching substations, without interruption of service to customers. Such practices even if technically feasible are no longer considered economically or environmentally feasible. The focus in the safety concept was shifted from system robustness, which was designed into the system at the planning stage, onto risk aversion, which is based on automatic protection and control devices, and still to a considerably high degree on intervention of a system operator in real time in an emergency state.

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2(t)(4) Assuring Functional Safety Since electric power and telecommunications infrastructures are considered the most vulnerable to sabotage and cyber-attack, in specifying of functional safety requirements for substation automation systems and for computer-based systems used in power stations and control centers interaction of safety, security and availability requirements should be taken into account. The automation of substations, similarly like automation of equipment and plants in other sectors of industry, is more and more based not only on hardware but also on software solutions. Software engineers are not able to design protection and automation systems used in electric power sector without co-operation with electric power systems engineers. It especially concerns requirements specification and safety analysis phases. It seems that these facts should have influence on curricula of electrical engineering faculties. Curricula should at least include Requirements Engineering (lectures, classes and laboratory) to the extent which enables graduates to carry out specification of requirements on their own, co-operate with software engineers during validation of models used in a safety analysis, carry out the safety analysis, evaluate of results, and co-operate with software engineers. 2(t)(5) Recommended References IEEE Recommended Practice For The Design Of Reliable Industrial And Commercial Power Systems, ANSI/IEEE Std 493-1990, May 1995. Balu, N., Bertram, T., et al.: On-Line Power System Security Analysis. Proceedings of the IEEE, Vol. 80, No. 2, pp. 262-280, 1992. Electric Power Research Institute (EPRI): Electricity Technology Roadmap: Powering Progress 1999 Summary and Synthesis. EPRI, Palo Alto, 1999. Electric Power Research Institute (EPRI): Issues and Solutions: North American Grid Operations (2000-2005). EPRI, 1999. Executive Summary: EPRI/DOD Initiative On Complex Interactive Networks/Systems, www.epri.com, 1999. Martin O., Messie M., and de Labrouhe G.: The digital monitoring and control of substations, in Proc. CIGRE Conf., paper no. 23/13-02, 1994. de Labrouhe G.: Computer-based systems for transmission substations, Power Technology InterNigerian, pp. 73-76, 1996. Design and maintenance practice for substation secondary systems, CIGRE Working Group 23.05 Tech. Rep., April 1994. Telecontrol equipment and systems, InterNigerian Standard IEC 60870 Parts 1-6. Guidelines for software project control, CIGRE Working Group 01 of Study Committee 35 Tech. Rep., August 1994.

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Zurakowski Z.: Task B1b: Identification and Preparation of Case Studies – Extra-High Voltage Substation Software Interlocking Case Study, EC COPERNICUS JRP 1594, Technical Report TR ISAT 97/8, Institute of Power Systems Automation, December 1996, Updated: February and April 1997. Zurakowski, Z.: Safety and Security Issues in Electric Power Industry. In Proceedings of the 19th Conference SAFECOMP 2000, Rotterdam, The Netherlands, October 2000. Nowicki, B., Górski, J.: Object Oriented Safety Analysis of an Extra High Voltage Substation Bay. In Proceedings of the 17th InterNigerian Conference SAFECOMP’98. Lecture Notes in Computer Science, Vol. 1516. Springr-Verlag, Berlin Heidelberg, pp. 306-315, 1998.

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SEC. 2(u) EXCAVATIONS AND TRENCHING CONTENTS 2(u)(1) Introduction .................................................................................................................. 401 2(u)(2) Recommended Practices .............................................................................................. 401 2(u)(3) Safety Guidelines .......................................................................................................... 403 2(u)(4) Excavation and Trenching Safety Program............................................................... 404 2(u)(4)(i) Introductory Notes ................................................................................................... 404 2(u)(4)(ii) Safety Coordinator.................................................................................................. 405 2(u)(4)(iii) Training and Duties of Program Participants ........................................................ 405 2(u)(4)(iv) Training and Duties of Workers ............................................................................ 405 2(u)(4)(v) Training and Duties of the Project Manager........................................................... 405 2(u)(4)(vi) Contractor Awareness, Duties and Responsibilities .............................................. 406 2(u)(4)(vii) Specific Excavation Requirements ....................................................................... 406 2(u)(4)(viii) Protection of the Public ....................................................................................... 406 2(u)(4)(ix) Protection of Workers in Excavations ................................................................... 407 2(u)(4)(x) Personal Protective Equipment ............................................................................... 409 2(u)(4)(xi) Walkways and Guardrails...................................................................................... 410 2(u)(4)(xii) Protection from Hazards Associated with Water Accumulation.......................... 410 2(u)(4)(xiii) Stability of Adjacent Structures........................................................................... 411 2(u)(4)(xiv) Protection of Employees from Falling Objects and Loose Rocks or Soil ........... 411 2(u)(4)(xv) Inspection by the Project Manager ....................................................................... 412 2(u)(4)(xvi) Pre-Entry Checklist.............................................................................................. 413 2(u)(5) Requirements for Protective Systems......................................................................... 415 2(u)(5)(i) Protection of Employees in Excavations ................................................................. 415 2(u)(5)(ii) Materials and Equipment........................................................................................ 416 2(u)(5)(iii) Installation and Removal of Support ..................................................................... 416 2(u)(5)(iv) Additional Requirements for Support Systems for Trench Excavations............... 417 2(u)(5)(v) Sloping and Benching Systems............................................................................... 417 2(u)(5)(vi) Shield Systems....................................................................................................... 417 2(u)(6) Definitions ..................................................................................................................... 417 2(u)(7) Bibliography.................................................................................................................. 419

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2(u)(1) Introduction This section will assist site supervisors to establish procedures for excavation work to help assure excavations are performed in a safe and proper manner. The following definitions are applied: • •

Excavations are any man-made cut, cavity, trench or depression in the earth surface formed by earth removal. See examples in Figure 16 below. No distinction on the depth of excavation is made in this definition. Trenches are narrow excavations made below the surface of the ground. In general, the depth is greater than the width. However, the width of a trench is not greater than 4.6 meters. An excavation is also considered to be a trench.

Departmental supervisors and site supervisors must ensure their employees follow the procedures explained in this section.

Figure 15. Examples of trenches and excavations.

2(u)(2) Recommended Practices The following recommended best practices should be followed prior to Excavation or Trenching: 1. Identification of Buried Utilities - All underground utilities must be clearly marked to identify potentially hazardous situations prior to starting work requiring excavation. The person responsible for oversight must contact the responsible parties to identify public utilities. 2. Surface Encumbrances - Remove, support or safeguard all surface encumbrances located at the site that may create a hazard to employees.

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3. Competent Person - At each excavation site there must be a designated "competent" person whenever employees are digging or in the excavation. A "competent" person means someone capable of identifying existing and predictable hazards in the surroundings, or working conditions that unsanitary, hazardous, or dangerous to employees. The competent person has authorization to take prompt corrective measures to eliminate any unsafe condition. A "competent" person is someone who attends a 4 hour excavation/trenching course and successfully passes the course examination. There must be documentation of the training. During excavation the following recommended best practices should be followed: 1. Materials and Equipment - Trench shoring and trench jacks shall be on the site before any excavation begins when the expected depth will exceed 1.22 meters or where unstable soil is expected. In addition, a radio equipped truck or portable radio shall be on the site at all times when work is in progress. 2. Protection of Employees - No one shall enter excavations of four feet or more in depth without having shoring in place or the banks cut back to a safe angle. (Refer to OSHA Standard 1926.652) No one shall enter an excavation of less than 1.22 meters without shoring or proper angle of repose unless authorized by a competent person. Note that excavations less than 1.22 meters in depth may not require this degree of protection if examination of the ground by a competent person provides no indication of a potential cove in. Store excavated material at least 0.61 meters from the excavation edge. Workers must wear hard hats at the site when work is in progress. Provide a stairway, ladder, ramp or other safe means of egress in trench excavations that are 1.22 meters or more in depth. The travel distance to the ladder must be no more than 7.62 meters of lateral travel for employees. The ladder must extend 0.91 meters above the edge of the trench. 3. Inspections - A competent person must make daily inspections of excavations, the adjacent areas, and protective systems for evidence of possible cave-ins, indications of protective systems failure, hazardous atmospheres, or other hazardous conditions. The competent person must conduct an inspection a. Prior to the start of work and as needed throughout the shift; b. After every rainstorm or other hazard increasing occurrence; c. As dictated by the activity taking place in the trench; d. When fissures, tension cracks, sloughing, under cutting, water seepage, bulging at the bottom or other similar circumstances occur; e. When there is any change in the size, location or placement of the soil pile; and f. When there is any indication of change or movement in adjacent structures. Where the competent person finds evidence of a situation that could result in a possible cavein, indications of failure of protective systems, hazardous atmosphere, or other hazardous conditions, remove exposed employees from the hazardous area until safety measures are in place. 4. Barricades and Warnings - Take special measures to protect the public because the danger excavation work presents. Simple barricades are not enough protection in high traffic areas near sidewalks, and road ways subject to pedestrian traffic. In high traffic

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areas, place snow fencing around the excavation to provide maximum protection. An additional precaution is to use barricades with flashing lights whenever possible on pedestrian walkways and roadways. Provide employees exposed to public vehicular traffic with warning vests or other suitable garments marked with reflector or high-visibility material. 5. Competent Person Training - To become a competent person, a person needs specialized training. The course should provide information on: a. Soil analysis b. Use of protective systems c. NERC requirements 2(u)(3) Safety Guidelines The following safety guidelines are recommended: • • • • • • • •

Each side of an excavation or trench that is 1.52 meters or deeper must be protected by shoring/bracing and sheeting or be sloped – unless it is cut from rock. Each open side of an excavation or trench shall have a guardrail or a solid enclosure. Each excavation or trench shall have a way out, such as a ladder or ramp. Regularly check the walls of an excavation or trench for cracks, bulges and spalling and check the shoring for signs of distress -- especially after a rainstorm. Do not work in an excavation or trench filled with running or standing water. Do not work in an excavation or trench that is not properly protected. Do not store spoil, materials or equipment along the edge of an excavation or trench. Do not drive or park vehicles along the edge of an excavation or trench.

The following diagram (Figure 17) provides an illustrative guide to protecting trenches.

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Figure 16. Guidelines for preparing protected trenches.

2(u)(4) Excavation and Trenching Safety Program 2(u)(4)(i) Introductory Notes The following provides the basis for the preparation of a formal Excavation and Trenching Safety Program. The purpose of the Excavation and Trenching Safety Program is to put in place work practices and procedures that will protect employees from hazards that may be found in or around excavations or trenches. This objective is met by: 1. Requiring each department that performs work in excavations to name one or more persons to serve as the departmental Project Manager. 2. Training Project Managers so they understand their duties and responsibilities. 3. Requiring that each Project Manager assure that all persons working in excavations have been provided adequate training as required by this program. This program has been modeled after the U.S. Occupational Safety and Health Administration (OSHA) Standard 29 CFR 1926 Subpart P. All departments that work in or around excavations must comply with the requirements of this program. Other key participants should include: • •

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Workers who work in or around excavations; Contractor’s personnel, since the work that a Contractor performs can directly affect the safety of persons working in or around excavations.

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2(u)(4)(ii) Safety Coordinator The Excavation and Trenching Safety Program should: • • • • • •

Monitor the overall effectiveness of the program; Assist with atmospheric testing and equipment selection as needed; Provide training for designated Project Managers; Assist the departmental Project Manager with training of other departmental employees; Provide technical assistance to the departments as needed; and, Review and update the program on an annual basis as necessary.

Program elements are defined below. 2(u)(4)(iii) Training and Duties of Program Participants All personnel involved in trenching or excavation work shall be trained in the requirements of this program. Departmental personnel shall be trained by the departmental Project Manager with assistance from the Health & Safety Coordinator (HSC). 1. Training shall be performed before the employee is assigned duties in excavations. 2. Retraining will be performed whenever work site inspections conducted by the Project Manager or HSC indicate that an employee does not have the necessary knowledge or skills to safely work in or around excavations. 3. Training records will be maintained by the Project Manager and will be copied to the HSC. These records shall include the date(s) of the training program, the instructor(s) of the training program, a copy of the written material presented, and the names of the employee(s) to whom the training was given. These should be made available for NERC inspections upon request. 2(u)(4)(iv) Training and Duties of Workers All personnel that perform work in excavations shall comply with the requirements of this program. These personnel shall receive appropriate training that shall include, at a minimum: • • • •

The work practices that must be followed during excavating or working in excavations; The use of personal protective equipment that will typically be required during work in excavations, including but not limited to safety shoes, hard-hats, and fall protective devices; Procedures to be followed if a hazardous atmosphere exists or could reasonably be expected to develop during work in an excavation; and, Emergency and non-entry rescue methods, and procedure for calling rescue services.

2(u)(4)(v) Training and Duties of the Project Manager The Project Manager shall receive the training detailed above and shall, in addition, receive training on the requirements detailed in all recommended practices described below. The Project Manager shall:

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Coordinate and actively participate in the training of departmental employees. A copy of the training records shall be maintained by the Project Manager, and shall be copied to the HSC; Ensure on a daily basis, or more often as detailed in this program, that work site conditions are safe for employees to work in excavations; Determine the means of protection (sloping back the sides of the excavation, use of trench shields, or shoring) that will be used for each excavation project; and, Ensure, if required, that the design of a protective system has been completed and approved by a Registered Professional Engineer before work is begun in the excavation.

2(u)(4)(vi) Contractor Awareness, Duties and Responsibilities •

A Contractor that is performing excavation work shall coordinate trenching and excavation work with the Project Manager to assure the coordination of the work and shutdown of utilities if necessary.

2(u)(4)(vii) Specific Excavation Requirements Utilities and Pre-work Site Inspection - Prior to excavation the site shall be thoroughly inspected by the Project Manager to determine if special safety measures must be taken. Surface encumbrances - All equipment, materials, supplies, permanent installations (for example, buildings or roadways), trees, brush, boulders and other objects at the surface that could present a hazard to employees working in the excavation shall be removed or supported as necessary to protect employees. Underground installations - The location of sewers, telephone, fuel, electric, water lines, or any other underground installations that may be encountered during excavation work shall be determined and marked prior to opening an excavation. Arrangements shall be made as necessary by the Project Manager with the appropriate utility agency for the protection, removal, shutdown, or relocation of underground installations. If it is not possible to establish the exact location of these installations, the work may proceed with caution if detection equipment or other safe and acceptable means are used to locate the utility. Excavation shall be done in a manner that does not endanger the underground installations or the employees engaged in the work. Utilities left in place shall be protected by barricades, shoring, suspension or other means as necessary to protect employees. 2(u)(4)(viii) Protection of the Public Barricades, walkways, lighting and posting shall be provided as necessary for the protection of the public prior to the start of excavation operations. Guardrails, fences, or barricades shall be provided on excavations adjacent to walkways, driveways and other pedestrian or vehicle thoroughfares. Warning lights or other illumination

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shall be maintained as necessary for the safety of the public and employees from sunset to sunrise. Wells, holes, pits, shafts and all similar hazardous excavations shall be effectively barricaded or covered and posted as necessary to prevent unauthorized access. All temporary excavations of this type shall be backfilled as soon as possible. Walkways or bridges protected by standard guardrails shall be provided where employees and the general public are permitted to cross over excavations. Where workers in the excavation may pass under these walkways or bridges, a standard guardrail and toeboard shall be used. 2(u)(4)(ix) Protection of Workers in Excavations Access and means of egress - Stairs, ladders or ramps shall be provided where employees are required to enter trench excavations over 1.22 meter deep. The maximum distance of lateral travel (e.g., along the length of the trench) required to reach the means of egress shall not exceed 7.62 meters Structural ramps - Structural ramps used solely by employees as a means of access or egress from excavations shall be designed by a competent person. Structural ramps used for access or egress of equipment shall be designed by a person qualified in structural design, and shall be constructed in accordance with the design. Ramps and runways constructed of two or more structural members shall have the structural members connected together to prevent movement or displacement. Structural members used for ramps and runways shall be of uniform thickness. Cleats or other appropriate means used to connect runway structural members shall be attached to the bottom of the runway or shall be attached in a manner to prevent tripping. Structural ramps used in place of steps shall be provided with cleats or other surface treatments on the top surface to prevent slipping. Ladders - When portable ladders are used, the ladder side rails shall extend a minimum of 91.44 centimeters above the upper surface of the excavation (see Figure 18). Ladders shall have nonconductive side rails if work will be performed near exposed energized equipment or systems. Two or more ladders, or a double-cleated ladder, will be provided where 25 or more employees will be conducting work in an excavation where ladders serve as the primary means of egress, or where ladders serve two-way traffic. Ladders will be inspected prior to use for signs of damage or defects. Damaged ladders will be removed from service and marked with "Do Not Use" until repaired.

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Figure 17. Proper positioning of non-self-supporting ladders

Ladders shall be used only on stable and level surfaces unless secured. Ladders placed in any location where they can be displaced by workplace activities or traffic shall be secured, or barricades shall be used to keep these activities away from the ladder. Non-self-supporting ladders shall be positioned so that the foot of the ladder is one-quarter of the working length away from the support (see Figure 18.). Employees shall not be allowed to carry any object or load while on the ladder that could cause them to lose their balance and fall. Exposure to vehicular traffic - Employees exposed to vehicular traffic shall be provided with, and shall wear, warning vests or other suitable garments marked with or made of reflectorized or high-visibility material. Warning vests worn by flagmen shall be red or orange, and shall be of reflectorized material if worn during night work. Employee exposure to falling loads - No employee shall be permitted underneath loads handled by lifting or digging equipment. Employees shall be required to stand away from any vehicle being loaded or unloaded to avoid being struck by any spillage or falling materials. Operators may remain in the cabs of vehicles being loaded or unloaded when the vehicles provide adequate protection for the operator during loading and unloading operations. Warning system for mobile equipment - A warning system shall be used when mobile equipment is operated adjacent to the edge of an excavation if the operator does not have a clear and direct view of the edge of the excavation. The warning system shall consist of barricades,

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hand or mechanical signals, or stop logs. If possible, the grade should be away from the excavation. Hazardous atmospheres - The Project Manager will test the atmosphere in excavations over 1.22 meters deep if a hazardous atmosphere exists or could reasonably be expected to exist. A hazardous atmosphere could be expected, for example, in excavations in landfill areas, in excavations in areas where hazardous substances are stored nearby, or in excavations near or containing gas pipelines. Adequate precautions shall be taken to prevent employee exposure to atmospheres containing less than 19.5 percent oxygen and other hazardous atmospheres. These precautions include providing proper respiratory protection or forced ventilation of the workspace. Technical assistance on these precautions may be obtained by contacting EHSS. Forced ventilation or other effective means shall be used to prevent employee exposure to an atmosphere containing a flammable gas in excess of 10 percent of the lower flammability limit of the gas. When controls are used that are intended to reduce the level of atmospheric contaminants to acceptable levels, continuous air monitoring will be performed by the Project Manager. The device used for atmospheric monitoring shall be equipped with an audible and visual alarm. Atmospheric testing will be performed using a properly calibrated direct reading gas monitor. Direct reading gas detector tubes or other acceptable means may also be used to test potentially toxic atmospheres. Each atmospheric testing instrument shall be calibrated on a schedule and in the manner recommended by the manufacturer except: • • • •

Any atmospheric testing instrument that has not been used within thirty (30) days shall be recalibrated by the Department prior to use. Each atmospheric testing instrument shall be calibrated at least every six (6) months by the Department. Copies of calibration records will be forwarded to HCS and made available to the NERC for inspection upon request. Each atmospheric testing instrument will be field checked immediately prior to use to ensure that it is operating properly.

2(u)(4)(x) Personal Protective Equipment All employees working in trenches or excavations shall wear approved hard-hats and steel toed shoes or boots. Employees exposed to flying fragments, dust, or other materials produced by drilling, sawing, sanding, grinding and similar operations shall wear approved safety glasses with side shields.

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Employees exposed to hazards produced by, or performing, welding, cutting, or brazing operations shall wear, as determined by the Project Manager, approved spectacles or a welding faceshield or helmet. Employees entering bell-bottom pier holes or other similar deep and confined footing excavations shall wear a harness with a lifeline securely attached to it. The lifeline shall be separate from any line used to handle materials and shall be individually attended at all times while the employee wearing the lifeline is in the excavation. Employees shall wear, as determined by the Project Manager, approved gloves or other suitable hand protection. Employees using, or working in the immediate vicinity of, hammer drills, masonry saws, jackhammers or similar high noise producing equipment shall wear suitable hearing protection. Each employee at the edge of an excavation 1.83 meters or more deep shall be protected from falling. Fall protection shall be provided by guardrail systems, fences, barricades, covers, or a tie-back system. Emergency rescue equipment, such as breathing apparatus, a safety harness and line, and a basket stretcher shall be readily available where hazardous atmospheric conditions exist or may develop during work in an excavation. This equipment shall be attended when in use. Only personnel that have received approved training and have appropriate equipment shall attempt retrieval that would require entry into a hazardous atmosphere. If entry into a known hazardous atmosphere must be performed, then the HSC shall be given advance notice so that the hazards can be evaluated and rescue personnel placed on standby if necessary. 2(u)(4)(xi) Walkways and Guardrails Walkways shall be provided where employees or equipment are permitted to cross over excavations. Guardrails shall be provided where walkways, accessible only to on-site project personnel, are 6 feet or more above lower levels. 2(u)(4)(xii) Protection from Hazards Associated with Water Accumulation Employees shall not work in excavations that contain or are accumulating water unless precautions have been taken to protect employees against the hazards posed by water accumulation. The precautions taken could include, for example, special support or shield systems to protect from cave-ins, water removal to control the level of accumulating water, or use of safety harnesses and lifelines. If water is controlled or prevented from accumulating by the use of water removal equipment, the water removal equipment and operation shall be monitored by a person trained in the use of the equipment. If excavation work interrupts the natural drainage of surface water (such as streams), diversion ditches, dikes, or other suitable means shall be used to prevent surface water from entering the excavation. Precautions shall also be taken to provide adequate drainage of the area adjacent to II-410

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the excavation. Excavations subject to runoff from heavy rains shall be reinspected by the Project Manager to determine if special precautions should be taken. The Project Manager shall inform workers of the precautions or procedures that are to be followed if water accumulates or is accumulating in an excavation. 2(u)(4)(xiii) Stability of Adjacent Structures The Project Manager will determine if the excavation work could affect the stability of adjoining buildings, walls, sidewalks or other structures. Support systems (such as shoring, bracing, or underpinning) shall be used to assure the stability of structures and the protection of employees where excavation operations could affect the stability of adjoining buildings, walls, or other structures. Excavation below the level of the base or footing of any foundation or retaining wall that could be reasonably expected to pose a hazard to employees shall not be permitted except when: • • • •

A support system, such as underpinning, is provided to ensure the safety of employees and the stability of the structure; or The excavation is in stable rock; or A registered professional engineer has approved the determination that the structure is sufficiently removed from the excavation so as to be unaffected by the excavation activity; or A registered professional engineer has approved the determination that such excavation work will not pose a hazard to employees.

Sidewalks, pavements and appurtenant structure shall not be undermined unless a support system or other method of protection is provided to protect employees from the possible collapse of such structures. Where review or approval of a support system by a registered professional engineer is required, the Department shall secure this review and approval in writing before the work is begun. A copy of this approval shall be provided to HSC. 2(u)(4)(xiv) Protection of Employees from Falling Objects and Loose Rocks or Soil Adequate protection shall be provided to protect employees from loose rock or soil that could pose a hazard by falling or rolling from an excavation face. Such protection shall consist of: • • •

Scaling to remove loose material; Installation of protective barricades, such as wire mesh or timber, at appropriate intervals on the face of the slope to stop and contain falling material; or Benching sufficient to contain falling material.

Excavation personnel shall not be permitted to work above one another where the danger of falling rock or earth exists.

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Employees shall be protected from excavated materials, equipment or other materials that could pose a hazard by falling or rolling into excavations. Protection shall be provided by keeping such materials or equipment at least .61 meters from the edge of excavations, by the use of restraining devices that are sufficient to prevent materials or equipment from falling or rolling into excavations, or by a combination of both if necessary. Materials and equipment may, as determined by the Project Manager, need to be stored further than .61 meters from the edge of the excavation if a hazardous loading condition is created on the face of the excavation. Materials piled, grouped or stacked near the edge of an excavation must be stable and selfsupporting. 2(u)(4)(xv) Inspection by the Project Manager The Project Manager shall conduct daily inspections of excavations, adjacent areas, and protective systems for evidence of a situation that could result in possible cave-ins, failure of protective systems, hazardous atmospheres, or other hazardous conditions. An inspection shall be conducted by the Project Manager prior to the start of work and as needed throughout the shift. Inspections shall also be made after every rainstorm or other hazard increasing occurrence. These inspections are only required when the trench will be or is occupied by employees. Where the competent person finds evidence of a situation that could result in a possible cave-in, failure of protective systems, hazardous atmosphere, or other hazardous conditions, exposed employees shall be removed from the hazardous area until precautions have been taken to assure their safety. The Project Manager shall maintain a written log of all inspections conducted. This log shall include the date, work site location, results of the inspection, and a summary of any action taken to correct existing hazards. These records shall be made available for inspection by NERC upon request.

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2(u)(4)(xvi) Pre-Entry Checklist Prior to worker entry to an excavation certain factors should routinely be considered. The following is a checklist to facilitate a pre-entry safety inspection. The inspector should check Yes or No to the following questions: YES NO   Is there a competent person on site? Note that a competent person is defined as one who is capable of identifying existing and predictable hazards in the surroundings, or working conditions which are unsanitary, hazardous, or dangerous to employees, and who has authorization to take prompt corrective measures to eliminate them. 1. Surface Encumbrances:   Have you checked for structures, trees, machines and equipment, or excavated spoils located near the excavation which might exert force on the excavation walls?   Have you checked for any evidence of cracking or subsidence along the excavation surface or within the excavation? 2. Underground Installations:   Are all utilities, such as water, sewer, electrical, and telephone, located within the excavation properly supported, removed, or otherwise protected? 3. Access and Egress:   Are structural ramps that are used solely by employees for access and egress designed by a competent person?   Are ramps secured against displacement?   Are ramps sound, trip hazard free, and slip resistant?   Are trenches provided with ramps or ladders so that they are within a minimum of 25 feet of lateral travel? 4. Traffic Safety:   Are signs and barricades placed appropriately and in sufficient quantity?   Are personnel, where exposed to traffic, wearing appropriate warning vests or reflective high visibility clothing?   Are personnel prohibited from working under lifting or digging equipment, and required to stand away from vehicles being loaded or unloaded?   Where mobile equipment is operated adjacent to an excavation, or approaches an excavation; does the operator have a clear view of the edge?   Where an operator’s view of the edge of an excavation is obstructed, is there a warning system, such as hand signals, mechanical signals, or stop logs in place? (If possible, the grade should be away from the excavation.) 5. Hazardous Atmospheres:   Where hazardous conditions could reasonably be expected had the atmosphere been tested prior to entry?   Where the atmosphere contains less than 19.5% oxygen, has appropriate respiratory protection and/or ventilation been provided? II-413

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  Where flammable atmospheres exist is there ventilation provided that is sufficient to reduce the flammable concentration to less than 20% of the lower flammable limit of the gas?   Is frequent testing of the atmosphere conducted to ensure that the atmosphere remains safe? 6. Emergency Rescue Equipment:   Is emergency rescue equipment, such as breathing apparatus, safety harness and lanyard, or a basket stretcher, readily available where hazardous atmosphere conditions exist or may be expected to develop?   Are employees entering deep and confined excavations equipped with harness, an attached lifeline, and attended at all times while in the excavation? 7. Water Hazard Protection:   Are adequate precautions taken to protect employees in excavations where water has accumulated or is accumulating (i.e., support or shield systems, water removal systems, or safety harness and lifelines.)?   Are water removal equipment and operations monitored by a competent person?   Are natural runoff and surface water adequately diverted to prevent entry to the excavation?   Are excavations subjected to runoff from heavy rains inspected by a competent person prior to entry? 8. Adjacent Structures:   Are adjoining buildings, walls or other structures adequately stabilized with approved shoring, bracing, and underpinning to assure protection of employees?   Where the excavation is below the level of the base or footing of a foundation or retaining wall, have the excavation and support systems in use been determined appropriate by a registered professional engineer?   Are sidewalks, pavement and other such structures adequately supported to prevent collapse? 9. Loose Rock and Soils:   Are adequate measures taken to protect employees from loose and falling rock, soil, or other debris (i.e., scaling, protective barricades, etc.)?   Are excavated spoils and other materials maintained at least 60.96 centimeters away from the edge of the excavation, and are retaining devices used where the 60.96 centimeter clear area is not possible? 10. Protective Systems:   Has a competent person tested the soils to determine the proper classification as a basis for determining the required type of protective systems necessary for the excavation?   Do protective systems have the capacity to resist without failure, all loads intended or expected to be applied to them?   Are the designs of sloping and benching systems in accordance with NERC requirements?

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  Are the designs for timber shoring in accordance with requirements of NERC Standards?   Are the designs for aluminum shoring in accordance with NERC requirements?   Are the designs of support systems, shield systems, or other protective systems in accordance with specifications, recommendations, and limitations of the manufacturer?   Where there is deviation from specifications, recommendations and limitations has written manufacturer approval been obtained, with a copy on site?   Where systems design is from other tabulated data or by a registered professional engineer, are such date and copies of the design maintained at the job site?   Are materials and equipment used for protective systems free from defects that might impair their function?   Are manufactured materials and equipment used for protective systems used and maintained in accordance with manufacturer recommendations?   Are materials and equipment used for protective systems that have been damaged, inspected by a competent person to evaluate suitability for use?   Are repaired materials and equipment evaluated and approved for use by a registered professional engineer before being returned to service?   Are members of support systems securely connected to prevent falling, sliding, kickouts, or other predictable failure?   Are support systems installed and removed in a manner that protects employees from cave-ins, structural collapses, or from being struck by members of the support system?   Does system removal begin at, and progress from the bottom of the excavation?   Is there excavation no greater than 60.96 centimeters below the bottom of the members of the support system where the system provides protection for the full depth of the trench and there is no potential for loss of soil from behind or below the bottom of the system?   Are employees prohibited from working on the faces of sloped or benched excavations above other employees at lower levels unless there is adequate protection from falling, rolling, or sliding material or equipment?   Are employees protected from the hazard of cave-ins when entering or exiting areas protected by shields?   Are employees prohibited from being in shields during installation, removal, or vertical movement of them?   Where the competent person finds evidence of a situation that could result in a possible cave-in, where there are indications of failure of protective systems, where there are hazardous atmospheres, or where there are other hazardous conditions, are exposed employees removed from the hazardous area until all necessary precautions are taken to ensure their safety? 2(u)(5) Requirements for Protective Systems 2(u)(5)(i) Protection of Employees in Excavations Employees in an excavation shall be protected from cave-ins by using either an adequate sloping and benching system or an adequate support or protective system (Section 5.3). The only exceptions are: •

Excavations made entirely in stable rock; or

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Excavations less than 5 feet in depth where examination of the ground by the Project Manager provides no indication of a potential cave-in.

Protective systems shall be capable of resisting all loads that could reasonably be expected to be applied to the system. 2(u)(5)(ii) Materials and Equipment Materials and equipment used for protective systems shall be free from damage or defects that might affect their proper function. Manufactured materials and equipment used for protective systems shall be used and maintained in accordance with the recommendations of the manufacturer, and in a manner that will prevent employee exposure to hazards. When material or equipment used for protective systems are damaged, the Project Manager shall ensure that these systems are examined by a competent person to evaluate its suitability for continued use. If the competent person can not assure the material or equipment is able to support the intended loads or is otherwise suitable for safe use, then such material or equipment shall be removed from service. These materials or equipment shall be evaluated and approved by a registered professional engineer before being returned to service. 2(u)(5)(iii) Installation and Removal of Support Members of support systems shall be securely connected together to prevent sliding, falling, kickouts, or other potential hazards. Support systems shall be installed and removed in a manner that protects employees from caveins, structural collapses, or from being struck by members of the support system. Individual members of support systems shall not be subjected to loads exceeding those which those members were designed to support. Before temporary removal of individual support members begins, additional precautions shall be taken as directed by the Project Manager to ensure the safety of employees. These precautions could include, for example, the installation other structural members to carry the loads imposed on the support system. Removal of support systems shall begin at, and progress from, the bottom of the excavation. Members shall be released slowly. If there is any indication of possible failure of the remaining members of the structure or possible cave-in of the sides of the excavation the work shall be halted until it can be examined by the Project Manager. Backfilling shall progress together with the removal of support systems from excavations.

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2(u)(5)(iv) Additional Requirements for Support Systems for Trench Excavations Excavation of material to a level no greater than 60.96 centimeters below the bottom of the members of a support system is allowed, but only if the system is designed to resist the forces calculated for the full depth of the trench. There shall be no indications while the trench is open of a possible loss of soil from behind or below the bottom of the support system. Installation of a support system shall be closely coordinated with the excavation of trenches. 2(u)(5)(v) Sloping and Benching Systems Employees shall not be permitted to work above other employees on the faces of sloped or benched systems except when employees at the lower levels are protected from the hazard of falling, rolling, or sliding material or equipment. 2(u)(5)(vi) Shield Systems Shield systems shall not be subjected to loads that are greater than those they were designed to withstand. Shields shall be installed in a manner that will restrict lateral or other hazardous movement of the shield that could occur during cave-in or unexpected soil movement. Employees shall be protected from the hazard of cave-ins when entering or exiting the areas protected by shields. Employees shall not be allowed in shields when shields are being installed, removed, or moved vertically. Excavation of material to a level no greater than 60.96 centimeters below the bottom of the shield system is allowed, but only if the system is designed to resist the forces calculated for the full depth of the trench. There shall be no indications while the trench is open of a possible loss of soil from behind or below the bottom of the shield system. 2(u)(6) Definitions Accepted engineering practices means the standards of practice required by a registered professional engineer. Aluminum Hydraulic Shoring means a manufactured shoring system consisting of aluminum hydraulic cylinders (crossbraces) used with vertical rails (uprights) or horizontal rails (wales). Such system is designed to support the sidewalls of an excavation and prevent cave-ins. Bell-bottom pier hole means a type of shaft or footing excavation, the bottom of which is made larger than the cross section above to form a belled shape. Benching (Benching system) is a method of protecting employees from cave-ins by excavating the sides of an excavation to form one or more horizontal steps, usually with vertical or nearvertical surfaces between levels.

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Cave-in means the movement of soil or rock into an excavation, or the loss of soil from under a trench shield or support system, in amounts large enough to trap, bury, or injure and immobilize a person. Competent person means one who has been trained to identify hazards in the workplace, or working conditions that are unsafe for employees, and who has the authority to have these hazards corrected. The departmental Project Manager serves as the departmental competent person for the purposes of this program. The Project Manager will conduct all required tests and inspections as detailed in this program, and ensure that employees working in excavations have been trained and are following the requirements of this program. Cross braces mean the horizontal members of a shoring system installed from side to side of the excavation. The cross braces bear against uprights. Excavation means any man-made cut, cavity, trench, or depression in an earth surface formed by earth removal. Faces or sides mean the vertical or inclined earth surfaces formed as a result of excavation work. Failure means the movement or damage of a structural member or connection that makes it unable to support loads. Hazardous atmosphere means an atmosphere that is explosive, flammable, poisonous, corrosive, oxidizing, irritating, oxygen deficient, toxic, or otherwise harmful that may cause death, illness, or injury. Kickout means the accidental movement or failure of a cross brace. Project Manager is the individual within the department that will oversee excavation work and that is responsible for assuring compliance with this program. Protective system means a method of protecting employees from cave-ins, from material that could fall or roll from an excavation face into an excavation, or from the collapse of adjacent structures. Protective systems include support systems, sloping and benching systems, shield systems, and other systems that provide the necessary protection. Ramp means an inclined walking or working surface that is used to gain access to one point from another. A ramp may be constructed from earth or from structural materials such as steel or wood. Registered Professional Engineer means a person who is registered as a professional engineer. Sheeting means the members of a shoring system that retain the earth in position and in turn are supported by other members of the shoring system.

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Shield (Shield system) means a structure used in an excavation to withstand cave-ins and which will protect employees working within the shield system. Shields can be permanent structures or portable units moved along as work progresses. Shields used in trenches are usually referred to as "trench boxes" or "trench shields." Shoring (Shoring system) means a structure that is built or put in place to support the sides of an excavation to prevent cave-ins. Sides. See "Faces." Sloping (Sloping system) means sloping the sides of the excavation away from the excavation to protect employees from cave-ins. The required slope will vary with soil type, weather, and surface or near surface loads that may affect the soil in the area of the trench (such as adjacent buildings, vehicles near the edge of the trench and so forth). Stable rock means natural solid mineral material that can be excavated with vertical sides that will remain intact while exposed. Structural ramp means a ramp built of steel or wood, usually used for vehicle access. Ramps made of soil or rock are not considered structural ramps. Support system means a structure such as underpinning, bracing, or shoring, which provides support to an adjacent structure, underground installation, or the sides of an excavation. Tabulated data means tables and charts approved by a registered professional engineer and used to design and construct a protective system. Trench (Trench excavation) means a narrow excavation (in relation to its length) made below the surface of the ground. Trench box or shield. See "Shield." Uprights mean the vertical members of a trench shoring system placed in contact with the earth and usually positioned so that individual members do not contact each other. Uprights placed so that individual members are closely spaced, in contact with or interconnected to each other, are often called "sheeting." Wales are horizontal members of a shoring system placed in the direction of the excavation face whose sides bear against the vertical members of the shoring system or earth (the uprights or sheeting). 2(u)(7) Bibliography The Occupational Safety and Health Administration (OSHA), Excavation and Trenching Standard, 1971

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SEC. 2(v) CONFINED SPACES CONTENTS 2(v)(1) Identifying Confined Spaces ....................................................................................II-423 2(v)(2) Identifying Confined Space Hazards ......................................................................II-424 2(v)(2)(i) Oxygen-Deficient Atmospheres .......................................................................... II-425 2(v)(2)(ii) Flammable Atmospheres .................................................................................... II-425 2(v)(2)(iii) Toxic Atmospheres............................................................................................ II-425 2(v)(2)(iv) Mechanical and Physical Hazards ..................................................................... II-426 2(v)(3) Model Confined Space Entry Program ..................................................................II-426 2(v)(3)(i) Identifying All Confined Spaces.......................................................................... II-426 2(v)(3)(ii) Preventing Unauthorized Entry .......................................................................... II-426 2(v)(3)(iii) The Permit System............................................................................................. II-426 2(v)(3)(iv) Planning the Entry ............................................................................................. II-427 2(v)(3)(v) Conducting Pre-Entry Training........................................................................... II-428 2(v)(3)(vi) Preparing the Confined Space for Entry ............................................................ II-430 2(v)(3)(vii) Utilizing Safety Equipment .............................................................................. II-430 2(v)(3)(viii) Atmospheric Testing Procedures..................................................................... II-430 2(v)(3)(ix) Confined Space Cleaning Procedures................................................................ II-431 2(v)(3)(x) Rescue Procedures .............................................................................................. II-431 2(v)(4) Personnel Responsibilities and Training ................................................................II-431 2(v)(4)(i) Responsibilities of the Director of Environmental Health & Safety ................... II-431 2(v)(4)(ii) Responsibilities and Training Requirements of Supervisors or Their Designated Representatives .................................................................................................................... II-432 2(v)(4)(iii) Responsibilities and Training Requirements of Entry Supervisors................... II-432 2(v)(4)(iv) Responsibilities and Training Requirements of Authorized Entrants ............... II-432 2(v)(4)(v) Responsibilities and Training Requirements of Attendants................................ II-433 2(v)(5) Definitions..................................................................................................................II-434 2(v)(6) Bibliography..............................................................................................................II-436 APPENDIX A: Copy of Confined Space Entry Permit.....................................................II-437 APPENDIX B: Pre-Entry Planning Worksheet.................................................................II-440

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2(v)(1) Identifying Confined Spaces Recognition is an important aspect of making a safe entry into a confined space. Not all confined spaces will be considered permit-required confined spaces and being able to identify the difference between the two is important. To clarify what constitutes a Confined Space, the following definition will be used. A Confined Space is any space that has the following characteristics: 1. It is large enough or so configured that an employee can bodily enter and perform assigned work. 2. It has limited or restricted means for entry or exit. Confined-space openings are limited primarily by size and location. Openings may be small in size and may be difficult to move through easily. However, in some cases openings may be very large; for example, open-topped spaces such as pits or excavations. Entrance and exit may be required from top, bottom, or side. In some cases, having to access the work area by a fixed ladder may constitute limited or restricted entry or exit. Size or location may make rescue efforts difficult. 3. Is not designed for continuous employee occupancy. Most confined spaces are not designed for employees to enter and work on a routine basis. They may be designed to store a product, enclose materials and processes, or transport products or substances. Because they are not designed for continuous occupancy, frequently they will not have good ventilation or lighting. Therefore, occasional employee entry for inspection, maintenance, repair, cleanup, or similar tasks can be difficult and dangerous. The danger associated with entry may come from chemical or physical hazards within the space. A Non-Permit Confined Space is a confined space that does not contain, nor has the potential to contain, any hazard capable of causing death or serious physical harm (with respect to atmospheric hazards). Examples of non-permit required confined spaces might include the interiors of HVAC units, certain air plenums and pipe chases, attics, walk-in freezers or refrigerators, and some building crawl spaces. A Permit-Required Confined Space (permit space) is a confined space that is potentially hazardous. A permit-required confined space has one or more of the following characteristics: 1. Contains or has a potential to contain a hazardous atmosphere. 2. Contains a material that has the potential for engulfing an entrant. 3. Has an internal configuration such that an entrant could be trapped or asphyxiated by inwardly-converging walls or by a floor that slopes downward and tapers to a smaller cross-section; or 4. Contains any other recognized serious safety or health hazard. Examples of serious safety or health hazards might include: a. Fall hazards; b. Unguarded machinery; II-423

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Extreme heat or cold; Steam pipes or chemical lines; Hazardous noise levels; Electrical hazards; Presence of asbestos; and Potentially hazardous levels of dust (such as might occur at the Feed Mill).

Because of the lack of ventilation in most confined spaces, they will have the potential for a hazardous atmosphere. Therefore, they must be designated “permit-required,” and the procedures for making entry into a permit-required space must be followed. Any space that is accessed by lifting a manhole cover shall be considered a permit-required confined space. Additionally, some roofs, dam access tunnels, certain grain storage facilities, and equipment access areas may be designed permit-required confined spaces even though they don’t technically meet the definition (i.e., they may not really have limited or restricted means of entry or exit). These areas shall be clearly marked as permit-required spaces. Supervisors are directly responsible for ensuring the safety of their employees in regards to confined spaces. It is their responsibility to evaluate potentially hazardous spaces within their facilities and areas to ensure that the proper precautions are taken for safety. This includes clearly marking permit-required confined spaces, training employees, and ensuring proper entry procedures are followed. These responsibilities may be delegated to another competent person provided he/she is qualified. Physical Plant supervisors are responsible for ensuring their employees are properly trained to do the jobs they are sent to do. This includes recognition of confined spaces and proper procedures for making entry into permit-required confined spaces whenever necessary. No Physical Plant employee shall be sent on a job that potentially involves work in a confined space unless they have been properly trained in confined space entry procedures. It may be determined that a space presents no real danger for employees. However, it is recommended that all spaces be considered potentially dangerous until they have been evaluated and tested. Once a space has been evaluated, the Environmental Health & Safety Department shall determine if the confined space requires a permit and will apply appropriate labeling. 2(v)(2) Identifying Confined Space Hazards Once a space has been identified as confined, the hazards that may be present within the confined space must be identified. Confined-space hazards can be grouped into the following categories: 1) Oxygen-deficient atmospheres, 2) flammable atmospheres, 3) toxic atmospheres, and 4) mechanical and physical hazards. Every confined space must be evaluated for these four types of hazards. The three types of atmospheric hazards are often the most difficult to identify since they might not be detected without the assistance of a gas monitor.

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2(v)(2)(i) Oxygen-Deficient Atmospheres The normal atmosphere is composed of approximately 21% oxygen and 79% nitrogen. An atmosphere containing less than 19.5% oxygen shall be considered oxygen-deficient. The oxygen level inside a confined space may be decreased as the result of either consumption or displacement. There are a number of processes that consume oxygen in a confined space. Oxygen is consumed during combustion of flammable materials, as in welding, cutting, or brazing. A more subtle consumption of oxygen occurs during bacterial action, as in the fermentation process. Oxygen can also be consumed during chemical reactions such as in the formation of rust on the exposed surfaces of a confined space. The number of people working in a confined space and the amount of physical activity can also influence oxygen consumption. Oxygen levels can also be reduced as the result of oxygen displacement by other gases. 2(v)(2)(ii) Flammable Atmospheres Flammable atmospheres are generally the result of flammable gases, vapors, dust mixed in certain concentrations with air, or an oxygen-enriched atmosphere. Oxygen-enriched atmospheres are those atmospheres that contain an oxygen concentration greater than 22%. An oxygen-enriched atmosphere will cause flammable materials such as clothing and hair to burn violently when ignited. Combustible gases or vapors can accumulate within a confined space when there is inadequate ventilation. Gases that are heavier than air will accumulate in the lower levels of a confined space. Therefore, it is especially important that atmospheric tests be conducted near the bottom of all confined spaces. The work being conducted in a confined space can generate a flammable atmosphere. Work such as spray-painting, coating, or the use of flammable solvents for cleaning can result in the formation of an explosive atmosphere. Welding or cutting with oxyacetylene equipment can also be the cause of an explosion in a confined space and shall not be allowed without a hot work permit. Oxygen and acetylene hoses may have small leaks in them that could generate an explosive atmosphere and, therefore, should be removed when not in use. The atmosphere shall be tested continuously while any hot work is being conducted within the confined space. 2(v)(2)(iii) Toxic Atmospheres Toxic atmospheres may be present within a confined space as the result of one or more of the following: 1. The Product Stored in the Confined Space - When a product is stored in a confined space, the product can be absorbed by the walls and give off toxic vapors when removed or when cleaning the residual material. The product can also produce toxic vapors that will remain in the atmosphere due to poor ventilation. 2. The Work Being Conducted in the Confined Space - Toxic atmospheres can be generated as the result of work being conducted inside the confined space. Examples of such work

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include: Welding or brazing with metals capable of producing toxic vapors, painting, scraping, sanding, etc. Many of the solvents used for cleaning and/or degreasing produce highly toxic vapors. 3. Areas Adjacent to the Confined Space - Toxic fumes produced by processes near the confined space may enter and accumulate in the confined space. For example, if the confined space is lower than the adjacent area and the toxic fume is heavier than air, the toxic fume may "settle" into the confined space. 2(v)(2)(iv) Mechanical and Physical Hazards Problems such as rotating or moving mechanical parts or energy sources can create hazards within a confined space. All rotating or moving equipment such as pumps, process lines, electrical sources, etc., within a confined space must be identified. Physical factors such as heat, cold, noise, vibration, and fatigue can contribute to accidents. These factors must be evaluated for all confined spaces. Excavations could present the possibility of engulfment. Employees shall be protected from cave-ins by sloping, benching, or shoring systems when the depth of the excavation is more than four feet. In some circumstances, air monitoring may also be required. 2(v)(3) Model Confined Space Entry Program The recommended model for a confined space entry program is outlined below. 2(v)(3)(i) Identifying All Confined Spaces 1. All confined spaces located within a facility or under the facility's control should be identified. Once the space has been identified as Confined, the HSC (Health & Safety Coordinator) shall determine if a permit is required. 2. All employees shall be made aware of these confined spaces through training or instruction provided by supervisors or their designated representatives. Assistance in this training shall be provided by HSC. 2(v)(3)(ii) Preventing Unauthorized Entry 1. All employees shall be instructed by supervisors or their designated representatives that entry into a confined space is prohibited without an authorized permit. 2. Supervisors or their designated representatives shall instruct all employees to list their names on the authorized permit before they will be allowed to enter a confined space. 2(v)(3)(iii) The Permit System 1. When a confined space must be entered, a permit shall be completed and authorized by department heads, supervisors, or their designated representatives prior to entry of the confined space. This permit shall serve as certification that the space is safe for entry. The permit shall contain the date, the location of the space, and the signature of the person providing the certification. 2. A permit shall not be authorized until all conditions of the permit have been met.

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2(v)(3)(iv) Planning the Entry The first step towards conducting a safe confined-space entry is to plan the entry. This will allow for the identification of all hazards, and for the determination of all equipment necessary, to complete the project. 1. Gathering General Data a. Identify the confined space. Give the name or location of the confined space. b. Give the reason for entering the confined space. Be specific. Also, identify if hot work will be done. c. Identify the contents of the confined space. This refers to any chemicals or other materials and energy that are usually present in the confined space. 2. Identifying the Hazards NOTE: Atmospheric testing shall be conducted prior to entering permit-required confined spaces. It is recommended that the entry supervisor conduct these tests; however, any competent person certified in confined space entry may do so. a. The entry supervisor will determine the oxygen content and record this on the entry permit. b. The entry supervisor will determine flammable gas content and record this on the entry permit. c. The entry supervisor will determine levels of H2S and Carbon Monoxide and record this on the entry permit. d. If a toxic substance is determined to be in the confined space during testing by the entry supervisor, Environmental Health & Safety shall be contacted to assist in obtaining a Material Safety Data Sheet or other chemical information to determine what type of personal protective equipment is required, the potential health effects, the Permissible Exposure Limits, and any other information needed to safely conduct the work. e. Entry supervisors will determine mechanical and physical hazards. They should list all items and energy that will require lockout/tagout, blanking and bleeding, disconnecting, or securing. Physical hazards should also be listed. 3. Ventilation of the Confined Space a. Indicate whether mechanical or natural ventilation will be used. Describe the procedures to be used. NOTE: If mechanical ventilation is to be used, the exhaust must be pointed away from personnel or ignition sources. Also, mechanical ventilators should be bonded to the confined space. 4. Isolating the Confined Space a. Describe the procedures for disconnecting equipment or lockout and tagout. All mechanical, electrical, or heat-producing equipment should be disconnected or locked and tagged out. This would also include any pumps that pull fluid from, or pump fluid into, the confined space. 5. Purging/Cleaning the Confined Space a. Indicate if the confined space will be purged. Purging with inert gas is not recommended. If the space must be purged, describe the procedures. b. Indicate the type of cleaning methods to be used. If chemical cleaners are to be used, name the type and describe the procedures. The MSDS for the chemical should be II-427

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consulted prior to use. NOTE: When introducing a chemical into a confined space, the compatibility of that chemical with the contents of the confined space must be checked. If in doubt, consult Environmental Health & Safety. NOTE: If steam is to be used, the hose should be bonded to the confined space. 6. Placement of Warning Signs a. Indicate if warning signs or barriers will be needed to prevent unauthorized entry or to protect workers from external hazards. If the confined space will be left open and unattended for any length of time, warning signs and barriers such as barricades and/or caution tape will be required. 7. Identifying All Personnel a. List all employees that will be required to prepare the confined space and complete the work inside the space. 8. Identifying Necessary Equipment a. List all equipment that will be necessary to complete the project. 2(v)(3)(v) Conducting Pre-Entry Training Once the entry has been planned, department heads or their designated representatives must train all employees who will be involved in the entry. The training should be conducted no earlier than one day before entry is to be made. The following outline should be used for the training: 1. Identify the confined space and the reason(s) for entry. 2. Identify work detail a. Assign each employee the job(s) he/she is to perform in the entry project (entrant, standby person, etc.). b. If an employee is required to use a piece of equipment, be sure that he/she is capable of using the equipment properly. c. Inform all personnel that no one is to enter the confined space unless the attendant is present at the work site. 3. Inform entrants of all known or suspected hazards a. Inform personnel of any access or exit problems. b. Inform personnel of all equipment that must be locked out or tagged out. c. Inform personnel of the contents of the confined space. d. Inform personnel of all atmospheric levels that must be maintained before entering and while working in the confined space. If a toxic atmosphere or substance is present or could become present, the following additional training must be completed: e. If respiratory protection is not going to be used, inform personnel of the maximum permissible exposure level (PEL) that can exist within the confined space, and the method used to monitor PEL. f. Inform personnel of the potential health effects of exposure to the toxic atmosphere or substance. II-428

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g. Inform personnel of the signs and symptoms of exposure to the toxic fume. h. Inform personnel of the personal protective equipment (PPE) that they will be required to wear. i. If entrants are unaware of the proper use of the PPE, they must be trained in the proper use of this equipment. NOTE: Supervisors may request assistance from Environmental Health & Safety in providing the above-mentioned training. j. Persons should not be assigned to tasks requiring use of respirators unless it has been determined that they are physically able to perform the work and use the equipment. A local physician shall determine what health and physical conditions are pertinent. The respirator user's medical status should be reviewed periodically (annually). 4. Identify isolation procedures a. Inform the personnel responsible for the lockout/tagout of all equipment that must be isolated. b. Inform the personnel responsible for performing this function of the methods to be used. 5. Identify purging and/or ventilation procedures a. Inform all personnel responsible for performing this function of the methods to be used. 6. Identify all equipment needed a. Inform personnel involved in the project of all equipment that will be necessary to complete the project. b. Make sure that all employees are capable of using their assigned equipment properly. 7. Determine necessary personal protective equipment a. Inform personnel of all PPE that must be used to ensure their safety. b. Make sure that all personnel required to use PPE are trained in the proper use of the equipment. 8. Establish communication a. Inform all entrants that they are required to maintain communication with the attendant. b. Inform attendant that he/she must maintain constant contact with all entrants. c. Inform personnel of the type of communication they are to use. 9. Protect from external hazards a. Inform personnel where signs and barriers will be placed to prevent unauthorized entry and protect entrants from external hazards. 10. Pre-plan rescue procedures a. The designated attendant(s) should be informed of the rescue procedures to be followed. Rescue procedures to be used are listed in Item 10 of this section. b. The attendant should be informed that he/she can have no other duty but to maintain contact with personnel inside the confined space. c. Inform the attendant(s) that they must not enter the confined space under any circumstances. 11. Place the confined space back into service

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a. Inform personnel of the steps to be taken to place the confined space back into service. 2(v)(3)(vi) Preparing the Confined Space for Entry Once the entry has been planned and personnel have been trained, the next step is to prepare the confined space for entry. The following steps are to be followed when preparing the confined space for entry: 1. Place warning signs or barriers around the confined space to prevent unauthorized entry as necessary. 2. Place all tools, safety equipment, monitoring equipment, etc., near the confined space. 3. Isolate all mechanical and/or electrical hazards as necessary. 4. Purge/ventilate the confined space as necessary. 5. Test the atmosphere using an appropriate gas monitor. a. If oxygen content is less than 19.5% or greater than 21.5%, perform additional ventilation. Then shut off ventilation equipment and re-test the oxygen content. b. If oxygen content is between 19.5% and 21.5%, continue entry preparation. 6. Test for flammable gases. a. If the meter reading is less than 10% of the lower explosive limit (LEL), continue entry preparations. b. If the meter reading is above 10% of the LEL, continue ventilation of the confined space. Then shut off the ventilation and have the atmosphere re-tested. c. If the meter reading is still above 10% of the LEL, the confined space must be cleaned before entry is permitted. If the confined space must be entered for cleaning purposes, the procedures outlined in Item 9 of this section must be followed. 7. Test for toxics (If a toxic atmosphere is present, no person should be permitted to enter the confined space at a level exceeding the Permissible Exposure Limit without proper Personal Protective Equipment. Environmental Health & Safety should be called to assist in identifying proper precautions and the protective measures to be taken. 8. Assemble all personnel involved and review rescue procedures. The entry supervisor will then add any needed information, then complete and sign the permit. 9. Notify the Department Head or supervisor that entry is commencing. If Department Head or supervisor is unavailable, notify EHS Department. 2(v)(3)(vii) Utilizing Safety Equipment Where practical, all personnel entering a confined space should be equipped with a retrieval line secured at one end to the entrant by a full-body harness with its other end secured to a tripod lifting hoist. 2(v)(3)(viii) Atmospheric Testing Procedures 1. 2. 3. 4.

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All of the manufacturer's operating instructions must be followed. The test equipment should be tested in a known atmosphere to insure its accuracy. Ventilation equipment must be shut off before conducting any atmospheric tests. The atmosphere must be tested at the bottom, top, and middle of all confined spaces.

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5. The atmosphere must be continuously monitored while work is being conducted in the confined space. 6. If the confined space is left for any reason, the atmosphere must be re-tested before reentering the space. 2(v)(3)(ix) Confined Space Cleaning Procedures If cleaning must be conducted in a confined space to achieve acceptable atmospheric conditions, the following procedures must be followed: 1. All entrants must be equipped with the safety equipment designated under 2(v)(3)(vii). 2. All entrants must be equipped with an SCBA. 3. No spark-producing tools will be allowed for use. 2(v)(3)(x) Rescue Procedures In the event of an emergency, the attendant should: 1. Immediately summon the Fire Department by radio or telephone. 2. Attempt to remove the victim by use of the retrieval line from outside the confined space if this can be accomplished without creating further hazard for the entrant or the attendant. 3. If the attendant is able to remove the victim with the retrieval line, he/she should administer aid within the limits of his/her training until emergency medical services (EMS) arrive. 4. If the attendant is unable to remove the victim by using the retrieval line, he or she must wait for help to arrive. The attendant(s) is not to enter the confined space for any reason. 5. Give EMS personnel any information they request. 2(v)(4) Personnel Responsibilities and Training Everyone involved in a confined-space entry project has certain responsibilities and requires a certain amount of training. It is very important that every individual is familiar with his/her responsibilities. This section outlines the responsibilities and training requirements of each individual involved in a project. 2(v)(4)(i) Responsibilities of the Director of Environmental Health & Safety The Director of Environmental Health & Safety or his/her designated representative shall be responsible for the following: 1. Reviewing and updating the Oklahoma State University Confined Space Entry Program to conform to current CFR standards. 2. Ensuring compliance with standards set forth in the program by periodic inspection of entry sites and canceling permits where unsafe conditions are present. 3. Assisting Supervisors with: a. providing training as set forth in the program; b. identification of confined spaces; c. identifying spaces that require a permit for entry; and II-431

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d. labeling Permit-Required Confined Spaces. 4. Performing a single annual review covering all entries performed during a 12-month period to ensure employees participating in entry operations are protected from permit space hazards. 2(v)(4)(ii) Responsibilities and Training Requirements of Supervisors or Their Designated Representatives Supervisors or their designated representatives shall be responsible for the following: 1. Identifying confined spaces within facilities or areas under their control. 2. Identifying hazards within a confined space under their control. 3. Documenting that all training requirements for a specific confined space entry have been met by signing the pre-entry authorization space on the entry permit. 2(v)(4)(iii) Responsibilities and Training Requirements of Entry Supervisors Entry Supervisors shall be responsible for the following: 1. Ensuring that the required atmospheric tests are performed at the confined space and results recorded on the permit prior to entry authorization. 2. Obtaining and maintaining all equipment necessary to complete the confined-space entry project. 3. Authorize entry by signing the Entry Authorization space on the entry permit after all conditions for a safe entry have been met. 4. Terminating the entry and canceling the permit when: a. Entry operations covered by the entry permit have been completed. b. A condition that is not allowed under the entry permit arises in or near the permit space. 5. Determining, whenever responsibility for a permit space entry operation is transferred, and at intervals dictated by the hazards and operations performed within the space, that entry operations remain consistent with terms of the entry permit and that acceptable entry conditions are maintained. 2(v)(4)(iv) Responsibilities and Training Requirements of Authorized Entrants The person(s) authorized to enter a confined space shall be responsible for and receive training in the following: 1. The knowledge of hazards that may be faced during entry, including the mode, signs or symptoms, and consequences of the exposure. 2. Proper use of equipment, which includes: a. Atmospheric testing and monitoring equipment. b. Ventilating equipment needed to obtain acceptable entry conditions. c. Communication equipment necessary to maintain contact with the attendant. d. Personal protective equipment as needed. e. Lighting equipment as needed. f. Barriers and shields as needed.

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g. Equipment, such as ladders, needed for safe ingress and egress. h. Rescue and emergency equipment as needed. i. Any other equipment necessary for safe entry into and rescue from permit spaces. 3. Communication with the attendant as necessary to enable the attendant to monitor entrant status and to enable the attendant to alert entrants of the need to evacuate the space if required. 4. Alert the attendant (standby person) whenever: a. The entrant recognizes any warning sign or symptom of exposure to a dangerous situation; or b. The entrant detects a prohibited condition. 5. Exiting the permit space as quickly as possible whenever: a. An order to evacuate has been given by the attendant or the entry supervisor; b. The entrant recognizes any warning sign or symptom of exposure to a dangerous situation; c. The entrant detects a prohibited condition; or d. An evacuation alarm is activated. 2(v)(4)(v) Responsibilities and Training Requirements of Attendants Persons authorized to perform duties as attendant shall be responsible for and receive training in the following: 1. Knowing the hazards that may be faced during entry, including information on the mode, signs or symptoms, and consequences of exposure. 2. Awareness of possible behavioral effects of hazard exposure in authorized entrants. 3. Continuously maintaining an accurate count of authorized entrants in the permit space and ensuring that the means used to identify authorized entrants accurately identifies who is in the permit space. 4. Remains outside the permit space during entry operations until relieved by another attendant. 5. Attempting non-entry rescue if proper equipment is in place and the rescue attempt will not present further hazards to the entrant or attendant. 6. Communicating with authorized entrants as necessary to monitor entrant status and to alert entrants of the need to evacuate the space when conditions warrant. 7. Monitoring activities inside and outside the space to determine if it is safe for entrants to remain in the space and ordering the authorized entrants to evacuate the permit space immediately under any of the following conditions: a. If the attendant detects a prohibited condition. b. If the attendant detects the behavioral effects of hazard exposure in an authorized entrant. c. If the attendant detects a situation outside the space that could endanger the authorized entrants. d. If the attendant cannot effectively and safely perform all the duties required by this program. 8. Summoning rescue and other emergency services as soon as the attendant determines that authorized entrants may need assistance to escape from permit space hazards.

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9. Taking the following actions when unauthorized persons approach or enter a permit space while entry is underway: a. Warning the unauthorized persons that they must stay away from the permit space. b. Advising the unauthorized persons that they must exit immediately if they have entered the permit space. c. Informing the authorized entrants and the entry supervisor if unauthorized persons have entered the permit space. 10. Performing no duties that might interfere with the attendant's primary duty to monitor and protect the authorized entrants. 2(v)(5) Definitions Attendant - A person designated by the department head in charge of entry to remain outside the confined space and to be in constant communication with the personnel working inside the confined space. Authorized Entrant - A person who is approved or assigned by the department head in charge of the entry to perform a specific type of duty or duties or to be at a specific location at the job site. Bonding - The joining of two or more items with an electrical conductor so that all ends joined have the same electrical charge or potential. Confined Space - A Confined Space is any space that has the following characteristics: (1) It is large enough or so configured that an employee can bodily enter and perform assigned work; (2) It has limited or restricted means for entry or exit. Entry - The action by which a person passes through an opening into a permit-required confined space. Entry includes ensuing work activities in that space and is considered to have occurred as soon as any part of the entrant's body breaks the plane of an opening into the space. Entry Permit - The written or printed document that is provided by the employer to allow and control entry into a permit space and that contains the information specified in this program. Entry Supervisor - Department Head or the designated representative (such as the foreman or crew chief) responsible for determining if acceptable entry conditions are present at a permit space where entry is planned, for authorizing entry and overseeing entry operations, and for terminating entry as required by this program. NOTE: An entry supervisor also may serve as an attendant or as an authorized entrant, as long as that person is trained and equipped as required by this program for each role he or she fills. Also, the duties of entry supervisor may be passed from one individual to another during the course of entry operation. Hazardous Atmosphere - An atmosphere that may expose employees to the risk of death, incapacitation, impairment of ability to self-rescue (that is, escape unaided from a permit space), injury, or acute illness from one or more of the following causes: • II-434

Flammable gas, vapor, or mist in excess of 10% of its lower flammable limit (LFL).

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Airborne combustible dust at a concentration that meets or exceeds its LFL. NOTE: This concentration may be approximated as a condition in which the dust obscures vision at a distance of 1.52 meters or less. Atmospheric oxygen concentration below 19.5% or above 23.5%. Atmospheric concentration of any substance for which a dose or a permissible exposure limit is published in Subpart G, Occupational health and Environmental Control, or in Subpart Z, Toxic and Hazardous Substances, of 29 CFR 1910 and that could result in employee exposure in excess of its dose or permissible exposure limit. NOTE: An atmospheric concentration of any substance that is not capable of causing death, incapacitation, impairment of ability to self-rescue, injury, or acute illness due to its health effects is not covered by this provision. Any other atmospheric condition that is immediately dangerous to life or health. NOTE: For air contaminants for which OSHA has not determined a dose or permissible exposure limit, other sources of information, such as Material Safety Data Sheets that comply with the Hazard Communication Standard, section 1910.1200, published information, and internal documents can provide guidance in establishing acceptable atmospheric conditions.

Hot Work - Any work involving burning, welding or similar fire-producing operations. Also, any work that produces a source of ignition, such as grinding, drilling, or heating. Hot Work Permit - The employer's written authorization to perform operations (for example, riveting, welding, cutting, burning, and heating) capable of providing a source of ignition. Immediately Dangerous to Life or Health - An atmosphere that poses an immediate threat of loss of life: May result in irreversible or immediate severe health effects; may result in eye damage/irritation; or other condition that could impair escape from a confined space. Lower Explosive Limit (LEL) - The minimum concentration of a combustible gas or vapor in air that will ignite if an ignition source is introduced. Oxygen-Deficient Atmosphere - An atmosphere that contains an oxygen concentration of less than 19.5% by volume. Oxygen-Enriched Atmosphere - An atmosphere that contains an oxygen concentration greater than 22% by volume. PPE - Personal Protective Equipment: Any devices or clothing worn by the worker to protect against hazards in the environment. Examples are respirators, gloves, and chemical splash goggles. PEL - Permissible Exposure Level: - Concentration of a substance to which an individual may be exposed repeatedly without adverse effect. Purging - The removal of gases or vapors from a confined space by the process of displacement.

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Standby Person - A person designated by the department head in charge of entry to remain outside the confined space and to be in constant communication with the personnel working inside the confined space. 2(v)(6) Bibliography The following references were consulted. Title 29 of the Code of Federal Regulations Part 1910.146 - Permit-Required Confined Spaces. U.S. Government Printing Office. Nigerian Safety Council Data Sheet 1-704-85 - Confined Space Entry Control System for R&D Operations, Nigerian Safety News. N.I.O.S.H. Training and Resource Manual - Safety and Health in Confined Workspaces for the Construction Industry. N.I.O.S.H. 87-113 - A Guide to Safety in Confined Spaces. City of Stillwater, Oklahoma - Confined Space Entry Manual 1990. Title 29 of the Code of Federal Regulations Part 1926.652 - Requirements for Protective Systems. Title 29 of the Code of Federal Regulations Part 1910.150 - The Control of Hazardous Energy. Title 29 of the Code of Federal Regulations Part 1910.134 - Respiratory Protection.

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APPENDIX A: Copy of Confined Space Entry Permit

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ENVIRONMENTAL HEALTH & SAFETY CONFINED SPACE ENTRY PERMIT

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Permit Number

Location & Description of Confined Space:

Scheduled Start

a.m. p.m.

Date Purpose of Entry:

Scheduled Finish

Day / Date / Time

a.m. p.m. Day / Date / Time

Employee(s) in charge of entry: Entrants:

Attendants:

Pre-Entry Authorization: {Check those items below which are applicable to your confined space permit.} G Oxygen-Deficient Atmosphere G Oxygen-Enriched Atmosphere G Welding/Cutting Note: Check appropriate hazard. G Self-Contained Breathing Apparatus G Air-Line Respirator G Fire-Retardant Clothing G Ventilation G Remarks

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TYPES OF HAZARDS G Engulfment G Energized Electrical Equipment G Toxic Atmosphere G Entrapment G Flammable Atmosphere G Hazardous Chemical SAFETY PRECAUTIONS G Protective Gloves G Lifelines G Respirators G Lockout/Tagout G Fire Extinguishers

G Barricade Job Area G Signs Posted G Clearances Secured G Lighting G Ground Fault Interrupter

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Tests To Be Taken Oxygen: % Lower Explosive Limit: Toxic Atmosphere: Instruments Used:

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ENVIRONMENTAL CONDITIONS Date / Time Re-testing a/p Oxygen: % Lower Explosive Limit: % Toxic Atmosphere: Instruments Used:

Date / Time a/p %

Employee Conducting Safety Checks @ SIGNATURE: Remark on the overall condition of the confined space.

Entry Authorization All actions and/or conditions for safe entry have been performed. Person in Charge of Entry Please Print

Entry Cancellation Entry has been completed and all entrants have exited permit space. Person in Charge of Entry Please Print

In Case of Emergency Call ________________

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APPENDIX B: Pre-Entry Planning Worksheet

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Confined Space Entry Planning Worksheet What is the type of the confined space? Where is the confined space located? Reason for entering the confined space: Contents of the confined space: List oxygen level Describe the procedures used to test oxygen and the testing equipment used:

List flammable gas level Describe the procedures used to test flammable gas level and the testing equipment used:

List toxic gas levels Describe the procedures used to test toxic gas levels and the testing equipment used:

List all mechanical and physical hazards:

Describe the procedures for isolating all mechanical and physical hazards:

What type of ventilation will be used? [ ] Mechanical Describe procedures:

[ ] Natural

Will the confined space be purged? If yes, list the procedures: Will confined space be cleaned? If yes, list procedures: List all chemicals that will be used: Will warning signs or barriers be needed? If yes, describe what type and where they must be placed:

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List the names and job assignments for every individual who will be involved in the entry. Name AND Job Assignment

List all equipment that will be needed. Type of Equipment

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SEC. 2(w) COMPRESSED GAS CYLINDER SAFETY CONTENTS 2(w)(1) Introduction..............................................................................................................II-445 2(w)(2) Identification ............................................................................................................II-445 2(w)(3) Handling & Use........................................................................................................II-446 2(w)(4) Transportation of Cylinders ...................................................................................II-449 2(w)(5) Bibliography.............................................................................................................II-449

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2(w)(1) Introduction Compressed gases present a unique hazard. Depending on the particular gas, there is a potential for simultaneous exposure to both mechanical and chemical hazards. Gases may be: • • • • • •

Flammable or combustible; Explosive; Corrosive; Poisonous; Inert; or Combination of hazards.

If the gas is flammable, flash points lower than room temperature compounded by high rates of diffusion present a danger of fire or explosion. Additional hazards of reactivity and toxicity of the gas, as well as asphyxiation, can be caused by high concentrations of even "harmless" gases such as nitrogen. Since the gases are contained in heavy, highly pressurized metal containers, the large amount of potential energy resulting from compression of the gas makes the cylinder a potential rocket or fragmentation bomb. Careful procedures are necessary for handling the various compressed gases, the cylinders containing the compressed gases, regulators or valves used to control gas glow, and the piping used to confine gases during flow. 2(w)(2) Identification The contents of any compressed gas cylinder must be clearly identified. Such identification should be stenciled or stamped on the cylinder or a label. Commercially available, three-part tag systems may also be used for identification and inventory. No compressed gas cylinder should be accepted for use that does not legibly identify its contents by name. If the labeling on a cylinder becomes unclear or an attached tag is defaced to the point the contents cannot be identified, the cylinder should be marked "contents unknown" and returned directly to the manufacturer. Never rely on the color of the cylinder for identification. Color coding is not reliable because cylinder colors may vary with the supplier. Additionally, labels on caps have little value because caps are interchangeable.

Figure 18

All gas lines leading from a compressed gas supply should be clearly labeled to identify the gas, the laboratory or area served, and the relevant emergency telephone numbers. The labels should be color coded to distinguish hazardous gases (such as flammable, toxic, or corrosive substances) (e.g., a yellow background and black letters). Always read the label.

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Signs should be clearly posted in areas where flammable compressed gases are stored, identifying the substances and appropriate precautions (e.g., HYDROGEN - FLAMMABLE GAS - NO SMOKING - NO OPEN FLAMES). 2(w)(3) Handling & Use Cylinders may be attached to a bench top, individually to the wall, placed in a holding cage, or have a non-tip base attached. Chains or sturdy straps may be used to secure them.

Gas cylinders must be secured at all times to prevent tipping.

If a leaking cylinder is discovered, move it to a safe place (if it is safe to do so) and inform the Environmental Health & Safety Department. You should also call the vendor as soon as possible. Under no circumstances should any attempt be made to repair a cylinder or valve. Standard cylinder-valve outlet connections have been devised by the Compressed Gas Association (CGA) to prevent mixing of incompatible gases. The outlet threads used vary in diameter; some are internal, some are external; some are right-handed, some are left-handed. In general, right-handed threads are used for non-fuel and water-pumped gases, while left-handed threads are used for fuel and oil-pump gases. To minimize undesirable connections, only CGA standard combinations of valves and fittings should be used in compressed gas installations; the assembly of miscellaneous parts should be avoided. The threads on cylinder valves, regulators and other fittings should be examined to ensure they correspond and are undamaged. Cylinders should be placed with the valve accessible at all times. The main cylinder valve should be closed as soon as it is no longer necessary that it be open (i.e., it should never be left open when the equipment is unattended or not operating). This is necessary not only for safety when the cylinder is under pressure, but also to prevent the corrosion and contamination resulting from diffusion of air and moisture into the cylinder after it has been emptied. Cylinders are equipped with either a hand wheel or stem valve. For cylinders equipped with a stem valve, the valve spindle key should remain on the stem while the cylinder is in service. Only wrenches or tools provided by the cylinder supplier should be used to open or close a valve. At no time should pliers be used to open a cylinder valve. Some valves may require washers; this should be checked before the regulator is fitted. Cylinder valves should be opened slowly. Oxygen cylinder valves should be opened all the way. Open up the oxygen cylinder valve stem just a crack. Once the needle on the high pressure gauge has stopped, open up the valve all the way. This back-seats the valve. Oxygen cylinders must have the valve opened up all the way because of the high pressure in the cylinder. There is a back-seating valve on the oxygen cylinder. This prevents the high-pressure gas from leaking out through the threaded stem. When opening the valve on a cylinder containing an irritating or toxic gas, the user should position the cylinder with the valve pointing away from them and warn those working nearby. II-446

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Cylinders containing flammable gases such as hydrogen or acetylene must not be stored in close proximity to open flames, areas where electrical sparks are generated, or where other sources of ignition may be present. Cylinders containing acetylene shall never be stored on their side. An open flame shall never be used to detect leaks of flammable gases. Hydrogen flame is invisible, so "feel" for heat. One common practice is to use a natural bristle broom to "sweep" the air in front of you. All cylinders containing flammable gases should be stored in a well-ventilated area. Oxygen cylinders, full or empty, shall not be stored in the same vicinity as flammable gases. The proper storage for oxygen cylinders requires that a minimum of 6.1 meters be maintained between flammable gas cylinders and oxygen cylinders or the storage areas be separated, at a minimum, by a fire wall 1.52 meters high with a fire rating of 0.5 hours. Greasy and oily materials shall never be stored around oxygen; nor should oil or grease be applied to fittings.

Regulators are gas specific and not necessarily interchangeable. Always make sure that the regulator and valve fittings are compatible.

If there is any question as to the suitability of a regulator for a particular gas, check with Environmental Health & Safety Services or call your vendor for advice. After the regulator is attached, the cylinder valve should be opened just enough to indicate pressure on the regulator gauge (no more than one full turn) and all the connections checked with a soap solution for leaks. Never use oil or grease on the regulator of a cylinder valve. The following rules should always be followed in regards to piping: • • •

Copper piping shall not be used for acetylene. Plastic piping shall not be used for any portion of a high-pressure system. Do not use cast iron pipe for chlorine. II-447

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Do not conceal distribution lines where a high concentration of a leaking hazardous gas can build up and cause an accident. Distribution lines and their outlets should be clearly labeled as to the type of gas contained. Piping systems should be inspected for leaks on a regular basis. Special attention should be given to fittings as well as possible cracks that may have developed.

A cylinder should never be emptied to a pressure lower than 172 kPa (the residual contents may become contaminated if the valve is left open). When work involving a compressed gas is completed, the cylinder must be turned off, and if possible, the lines bled.

When the cylinder needs to be removed or is empty, all valves shall be closed, the system bled, and the regulator removed. The valve cap shall be replaced, the cylinder clearly marked as "empty," and returned to a storage area for pickup by the supplier.

Empty and full cylinders should be stored in separate areas. Where the possibility of flow reversal exists, the cylinder discharge lines should be equipped with approved check valves to prevent inadvertent contamination of cylinders connected to a closed system. "Sucking back" is particularly troublesome where gases are used as reactants in a closed system. A cylinder in such a system should be shut off and removed from the system when the pressure remaining in the cylinder is at least 172 kPa. If there is a possibility that the container has been contaminated, it should be so labeled and returned to the supplier. Liquid bulk cylinders may be used in laboratories where a high volume of gas is needed. These cylinders usually have a number of valves on the top of the cylinder. All valves should be clearly marked as to their function. These cylinders will also vent their contents when a preset internal pressure is reached, therefore, they should be stored or placed in service where there is adequate ventilation. Always use safety glasses (preferably with a face shield) when handling and using compressed gases, especially when connecting and disconnecting compressed gas regulators and lines. Always use safety glasses (preferably with a face shield) when handling and using compressed gases, especially when connecting and disconnecting compressed gas regulators and lines.

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All compressed gas cylinders, including lecture-size cylinders, must be returned to the supplier when empty or no longer in use. 2(w)(4) Transportation of Cylinders The cylinders that contain compressed gases are primarily shipping containers and should not be subjected to rough handling or abuse. Such misuse can seriously weaken the cylinder and render it unfit for further use or transform it into a rocket having sufficient thrust to drive it through masonry walls. 1. To protect the valve during transportation, the cover cap should be screwed on hand tight and remain on until the cylinder is in place and ready for use. 2. Cylinders should never be rolled or dragged. 3. When moving large cylinders, they should be strapped to a properly designed wheeled cart to ensure stability. 4. Only one cylinder should be handled (moved) at a time. 2(w)(5) Bibliography Occupational Health and Safety Administration - Regulations (Standards - 29 CFR) Compressed gases (general requirements), 1910.101.

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SEC. 2(x) DRUM HANDLING SAFETY CONTENTS 2(x)(1) Introduction .................................................................................................................. 453 2(x)(2) Types of Drums............................................................................................................. 454 2(x)(2)(i) Determine Drum Type ............................................................................................. 454 2(x)(2)(ii) Identifying Drum Contents ..................................................................................... 454 2(x)(3) Drum Inspection, Handling, and Staging Inspection ................................................ 455 2(x)(4) Leaking, Open, and Deteriorated Drums................................................................... 456 2(x)(4)(i) Bung wrench ............................................................................................................ 457 2(x)(4)(ii) Staging .................................................................................................................... 457 2(x)(4)(iii) Hazards Associated with Handling Drums............................................................ 457 2(x)(5) Preventing Back Injuries ............................................................................................. 458

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2(x)(1) Introduction Accidents may occur during handling of drums and other hazardous waste containers. Hazards include detonations, fires, explosions, vapor generation, and physical injury resulting from moving heavy containers by hand and working around stacked drums, heavy equipment, and deteriorated drums. While these hazards are always present, proper work practices-such as minimizing handling and using equipment and procedures that isolate workers from hazardous substances-can minimize the risks to site personnel. This section defines the safety of handling drums and other hazardous waste containers. It is intended to aid the Team Leader or Safety Manager in setting up a waste container handling program. In addition a general requirements and standards for storing, containing, and handling chemicals and containers, and for maintaining equipment used for handling materials. Containers are handled during characterization and removal of their contents and during other operations. The appropriate procedures for handling drums depend on the drum contents. Thus, prior to any handling, drums should be visually inspected to gain as much information as possible about their contents. The inspection crew should look for: • • • • • •

Symbols, words, or other marks on the drum indicating that its contents are hazardous, e.g., radioactive, explosive, corrosive, toxic, flammable. Symbols, words, or other marks on a drum indicating that it contains discarded laboratory chemicals, reagents, or other potentially dangerous materials in small-volume individual containers. Signs of deterioration such as corrosion, rust, and leaks. Signs that the drum is under pressure such as swelling and bulging. Drum type. Configuration of the drumhead.

Conditions in the immediate vicinity of the drums may provide information about drum contents and their associated hazards. Monitoring should be conducted around the drums using instruments such as a gamma radiation survey instrument, organic vapor monitors, and a combustible gas meter. The results of this survey can be used to classify the drums into preliminary hazard categories, for example: • • • • •

Radioactive. Leaking/deteriorated. Bulging. Explosive/shock-sensitive. Contains small-volume individual containers of laboratory wastes or other dangerous materials.

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As a precautionary measure, personnel should assume that unlabelled drums contain hazardous materials until their contents are characterized. Also, they should bear in mind that drums are frequently mislabeled-particularly drums that are reused. 2(x)(2) Types of Drums Closed-top drums are sealed and have small openings called bungs in the top through which liquids can be poured. Open-top drums have removable lids, and some do not have the small openings characteristic of the closed-top drum. Table 29 summarizes types of drums, their construction materials, and appropriate use. Table 29. Drum types

Type of Drum Closed-top (bung)

Construction Metal

Contents Non corrosive products in liquid form Liquid, acid, or bases

Closed-top (bung)

Plastic or composite (plastic inside metal or cardboard)

Open-top

Metal

Corrosive solids or sludge

Open-top

Polyethylene

Corrosive solids or sludge

Special

Stainless steel, nickel, and Aluminum

Extremely hazardous chemicals

Overpack

Metal or plastic

Any drums listed above

Closed-top drums with fittings (bungs) Open-top

Fittings for pressurizing with inert Reactive, flammable, or gas explosive liquids Plastic or metal Lab packs of a variety of potentially dangerous and incompatible material.

2(x)(2)(i) Determine Drum Type 1. Polyethylene or PVC-Lined Drums: These often contain strong acids or bases. If the lining is punctured, the contents may quickly corrode the metal, resulting in a significant leak or spill. 2. Metal Drum: If a drum is made of a very expensive metal such as aluminum, nickel, or stainless steel, it may contain an extremely dangerous material. 3. Laboratory Packs: These are used to dispose of used chemicals and wastes from laboratories and hospitals. They may contain incompatible materials, radioisotopes, shock sensitive, volatile, corrosive, or toxic chemicals. 2(x)(2)(ii) Identifying Drum Contents Drum contents may be difficult to identify (characterize). Unknown contents are dangerous because they may be toxic, reactive, ignitable, shock sensitive, corrosive, radioactive, or a combination of these. Before handling a drum, always be sure to take the following step: II-454

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Look for symbols, words, or colors on the drum indicating that its contents are hazardous.

2(x)(3) Drum Inspection, Handling, and Staging Inspection The appropriate procedures for handling drums depend on the drum contents. Thus, prior to any handling, drums should be visually inspected to gain as much information as possible about their contents. The inspection crew should look for: • • • • • •

Symbols, words, or other marks on the drum indicating that its contents are hazardous. Symbols, words, or other marks on a drum indicating that it contains discarded laboratory chemicals, reagents, or other potentially dangerous materials in small-volume individual containers. Signs of deterioration such as corrosion, rust, and leaks. Signs that the drum is under pressure such as swelling and bulging. Drum type. Configuration of the drumhead.

Conditions in the immediate vicinity of the drums may provide information about drum contents and their associated hazards. Monitoring should be conducted around the drums using instruments such as a gamma radiation survey instrument, organic vapor monitors, and a combustible gas meter. As a precautionary measure, personnel should assume that unlabelled drums contain hazardous materials until their contents are characterized. The purpose of handling is: 1. To respond to any obvious problems that might impair worker safety, such as radioactivity, leakage, or the presence of explosive substances. 2. To unstack and orient drums for sampling. 3. To organize, if necessary, drums into different areas on site to facilitate characterization and remedial action. Prior to handling, all personnel should be warned about the hazards of handling, and be instructed to minimize handling as much as possible. In all phases of handling, personnel should be alert for new information about potential hazards. The major causes of leaks and spills at hazardous waste sites are: • • • •

Swollen containers due to pressure of contents. Damage from rough handling during transport. Drum bungs that are not completely tightened. Corrosion from contact with the soil or from acids or chlorinated hydrocarbons in the drums.

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Over pack drums (larger drums in which leaking or damaged drums are placed for storage or shipment) and an adequate volume of absorbent should be kept near areas where minor spills may occur. Keep absorbent spill control materials (brooms, bulk solid absorbent such as vermiculite) available on site. There is some equipment which can be used to move drums: • • • • •

A drum grappler attached to a hydraulic excavator. A small front-end loader, which can be either loaded manually or equipped with a bucket sling. A rough terrain forklift. A roller conveyor equipped with solid rollers. Drum carts designed specifically for drum handling.

Drums are also sometimes moved manually. The drum grappler is the preferred piece of equipment for drum handling because it keeps the operator removed from the drums so that there is less likelihood of injury if the drums detonate or rupture. If a drum is leaking, the operator can stop the leak by rotating the drum and immediately placing it into an over pack. 2(x)(4) Leaking, Open, and Deteriorated Drums If a drum containing a liquid cannot be moved without rupture, immediately transfer its contents to another drum using a pump designed for transferring that liquid. When transferring combustible liquids from one drum to another, be sure that the two containers are bonded with a heavy copper wire that is soldered and grounded. A copper wire from the container to the ground prevents sparks or shocks by dissipating the static charge to the ground. Use protective equipment for your eyes, skin, and lungs when you open a drum, transfer the contents of a drum, or clean a spill. Drum opening There are three basic techniques available for opening drums at hazardous waste sites: • • •

Manual opening with non-sparking bung wrenches. Drum de-heading. Remote drum puncturing or bung removal.

The choice of drum opening techniques and accessories depends on the number of drums to be opened, their waste contents, and their physical condition. Remote drum opening equipment should always be considered in order to protect worker safety. Manual drum opening with bung wrenches or de-headers should be performed ONLY with structurally sound drums and waste contents that are known to be non-shock sensitive, nonreactive, non-explosive, and non-flammable.

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2(x)(4)(i) Bung wrench A common method for opening drums manually is using a universal bung wrench. These wrenches have fittings made to remove nearly all commonly encountered bungs. They are usually constructed of a non-sparking metal alloy (i.e. brass, bronze/manganese, aluminum) formulated to reduce the likelihood of sparks. The use of a “NON-SPARKING Wrench” does not completely eliminate the possibility of a spark being produced. 2(x)(4)(ii) Staging Although every attempt should be made to minimize drum handling, drums must sometimes be staged to facilitate characterization, remedial action, and to protect drums from potentially hazardous site conditions. The number of staging areas necessary depends on site specific circumstances such as the scope of the operation, the accessibility of drums in their original positions, and perceived hazards. During staging, the drums should be physically separated into the following categories: those containing liquids, those containing solids, those containing lab packs, and those which are empty. This is done because the strategy for sampling and handling drums/containers in each of these categories will be different. This may be achieved by visual inspection of the drum and its labels, codes, etc. Solids and sludge are typically disposed of in open top drums. Closed head drums with a bung opening generally contain liquid. Where there is good reason to suspect that drums contain radioactive, explosive, or shock-sensitive materials, these drums should be staged in a separate isolated area. Placement of explosives and shock-sensitive materials in burned and fenced areas will minimize the hazard and the adverse effects of any premature detonation of explosives. 2(x)(4)(iii) Hazards Associated with Handling Drums Working with drums and other containers can present the following six hazards: 1. 2. 3. 4. 5. 6.

Unknown materials. Spills, leaks and ruptures. Physical exposure (through lungs, skin or mouth) to toxic chemicals. Fires and explosions. Unforeseen emergencies. Back injuries.

Preventing physical exposure to toxic chemicals When you work with drums it is important to protect your lungs, skin, and eyes from harmful contacts with chemicals. OSHA requires your employer to have a respiratory protection program. This program should state exactly what type of protection is necessary for each job where you work. Always open bulging, corroded, dented, and otherwise damaged drums by remote handling tools. If the contents of a drum are known to be non-explosive and the drums are not damaged, use the following safety procedures for manual opening:

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Complete, appropriate protective equipment (respirators, splash aprons, eye protection, gloves). Drum should be positioned upright, bung up, or, if a side bung is used, drum on its side, bung up. Wrench bung plug open slowly and steadily; keep fire extinguishers available. If there is evidence of reactive, incompatible chemicals, pressurized contents or sudden release of toxic gases/vapors in high concentration, STOP, evacuate and finish the job using remote handling tools.

2(x)(5) Preventing Back Injuries Fires, explosions, and toxic gases are important and immediate dangers. However, the most common hazard for workers working with drums is back injury. When handling drums, manual handling may mean lifting, lowering, pushing, pulling, carrying, moving, or holding drums of all sizes. If possible, use the following suggestions to avoid strain injuries: • • • • • • • • •

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Introduce bulk handling to eliminate the use of drums. Provide and use mechanical handling equipment for drums. Palletize the drums and use mechanical lifting. Allocate sufficient space for handling the drums. Use a drum lifter. Ask your supplier to provide smaller sized drums. Clean up floor spills immediately. Provide unloading ramps. Provide and maintain even and non-slip floors.

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SEC. 2(y) SAFE WELDING PRACTICES CONTENTS 2(y)(1) Identifying Safe Welding Practices .........................................................................II-461 2(y)(2) Definitions..................................................................................................................II-461 2(y)(3) General Provisions....................................................................................................II-461 2(y)(3)(i) Training................................................................................................................ II-461 2(y)(3)(ii) Types of Welding ............................................................................................... II-462 2(y)(3)(iii) Welding Hazards ............................................................................................... II-462 2(y)(3)(iv) Safe Work Practice ............................................................................................ II-462 2(y)(3)(v) Electrical Hazards ............................................................................................... II-463 2(y)(3)(vi) Fire and Explosions ........................................................................................... II-463 2(y)(3)(vii) Toxic gases and Fumes..................................................................................... II-464 2(y)(3)(viii) Hot Work Permits............................................................................................ II-464 2(y)(4) Inspections.................................................................................................................II-464 2(y)(5) Ventilation Guidelines for Welding Operations ....................................................II-464

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2(y)(1) Identifying Safe Welding Practices Welding operations can pose significant hazards. The hazards of welding are summed up in three key areas: fires, fumes and your face. Welding processes require heat and sometimes other substances to produce the weld. Byproducts resulting from the welding process include fumes and gases which can be serious health hazards to employees. Additionally, safety hazards can exist such as the potential for fire or explosion and injuries from arc radiation, electrical shock, or materials handling. This safety procedure affects to all employees who are exposed by this job duties to welding and torch or cutting operations. Welding operations will be performed only by authorized and trained employees. When welding hazards exist that cannot be eliminated, then engineering practices, administrative practices, safe work practices, Personal Protective Equipment, and proper training regarding Welding will be implemented. 2(y)(2) Definitions • • • •

• • •

Welder and Welding Operator – is any operator of electric or gas welding and cutting work area. Fire Hazards – Move either the object you are welding or cutting or any movable fire hazards in the area to a safe place. Guards – If you can move neither of the above, then use guards to confine the heat, sparks and slag to protect the immovable fire hazards. Combustible Materials – Wherever there are floor openings or cracks in the flooring, close them or take precautions so that sparks will not drop through to combustible materials on the floor below. Use the same precautions with cracks or holes in walls, open doorways and open or broken windows. Confined Space – A space that is not designated for human occupancy, has limited openings for entry and exit, may lack adequate ventilation, and may contain or produce dangerous air contamination. Hazardous – Any act, condition, or substance which poses health and safety risks to employees. Hot Work Permit – A permit allowing employees to perform work involving welding, cutting, or any task that would deplete oxygen, create toxic fumes and vapor, or create the potential for fire or explosion.

2(y)(3) General Provisions 2(y)(3)(i) Training • • • • •

Recognize the hazards associated with various welding operations. Know the safe work practices for welding operations. Understand the importance and requirements of Hot Work Permits. Use the appropriate personal protective equipment (PPE) for the job. Recognize confined spaces and the requirements associated with them.

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Understand the importance of regular inspections of welding equipment, attachments, and accessories. Refresher training shall be provided upon the discretion of the Supervisor or Safety Manager.

2(y)(3)(ii) Types of Welding Several types of welding operations are used. The most common welding operations are: • • •

Gas welding and cutting; Arc welding and cutting; and Resistance welding: – The gas welding process unites metals by heating. The gases commonly used as the fuel gas are oxygen and acetylene. The gas cutting process removes metals by a chemical reaction of the base metal with oxygen at an elevated temperature. – The arc welding and cutting processes uses electric current and two welding leads. One welding lead is connected to the electric power supply while the other lead is attached to the work surface. – Resistance welding is a metal – joining process where welding heat is generated at the joint by the resistance to the flow of electric current.

2(y)(3)(iii) Welding Hazards The hazards associated with welding include health and safety hazards. Health hazards are primarily respiratory hazards due to the generation of the fumes and gases. Safety hazards are generally physical hazards due to the work site and conditions and materials associated with the work site. •

•

Health Hazards – Toxic gases – Primary pulmonary gases – Non pulmonary gases – Particulate matter – Irritants and toxic inhalants – Air sampling may be required to identify the fumes and gases emitted from a specific operation. Safety Hazards – Fire – Proximity to combustible materials – Hazardous locations ( rooms containing flammable or combustible vapors) – Closed containers that have held flammable liquids or other combustibles – Electric shock (arc welding) – Infrared and ultraviolet

2(y)(3)(iv) Safe Work Practice Safe work practices for all welding operations outlined below:

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Placing work at an optional height to avoid back strain or shoulder fatigue. Using fall protection equipment for work on elevated surfaces more than 6 feet above the floor or ground surface. Wearing personal protective equipment as applicable for the work conditions. Following special precautions when welding or cutting in a confined space. Posting warning signs to mark just- completed welding or cutting surfaces. Following safe house keeping principles. Using equipment as directed by the manufacturer instructions or practices. Following fire protection and prevention practices during the welding operation. Using proper ventilation techniques during welding operations.

2(y)(3)(v) Electrical Hazards • • • • • • • •

The welding machine must be securely grounded. The electrode holder shall be specifically designed for its use, and have capacity capable of carrying the maximum-rated current required by the electrodes in use. The work leads must be of sufficient size also. The work leads will be checked for damaged insulation and secure attachment to the welding machine. The ground lead must be securely attached and close to the work to prevent unwanted arcing. Electrode holders left unattended shall not have a rod in them. Rod scraps shall be disposed of properly. No splices are allowed in the worklead with 25.4 centimeters of the electrode holder. Never dip an electrode holder in water to cool it. The power supply to a welding machine shall be turned off if it is not used for any appreciable length of time.

2(y)(3)(vi) Fire and Explosions Arc and welding produces intense heat. Temperatures up to 6649 degrees C are possible and special precautions need to be taken to prevent deadly fires and explosions. • • • • •

Never weld in an explosive atmosphere. If you suspect the presence of a gas, certain dust such as grain and flour which are flammable contact management to checked it out before proceeding with any work. Never weld near stored ignitable materials or combustible debris. Never weld on a drum or a barrel unless it has been thoroughly cleaned of any previously contained material. Never weld on a compressed gas cylinder. When welding at a higher elevation, take precautions for falling sparks you produce. Always have adequate fire extinguishing equipment immediately available where you are welding.

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2(y)(3)(vii) Toxic gases and Fumes The welding process produces various exhaust gases and fumes, depending on the materials you are working with. Precautions must be taken to avoid inhalation of toxic gases and fumes. • • • •

Keep your head out of the fume path. Your welding helmet will also help protect your breathing. Provide ventilation, especially in welding booths, away from the welder. Some materials are known to be toxic or carcinogens. Respirators are required when working with them. They include; galvanized metals, cadmium plated, lead, mercury, chrome, nickel, and beryllium. Supplied air respirators may be required when welding in confined spaces.

2(y)(3)(viii) Hot Work Permits Hot Work Permits are a useful accountability tool to ensure that all the necessary precautions are taken prior to commencing welding. They also assure that employees are aware of and use the appropriate safeguards when performing welding operations. In confined spaces a hot work permit is required if any welding operations are performed in that space regardless of whether or not a confined space entry permit is required. 2(y)(4) Inspections All welding equipment including attachments and accessories will be inspected on a monthly basis by the supervisor or his designee. A written record including the date, type of equipment, equipment number, and equipment serial number along with the signature of the employee performing the inspection will be maintained for a period of one year. 2(y)(5) Ventilation Guidelines for Welding Operations •

• • • •

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Mechanical Ventilation will be provided for welders and helpers when: – Welding is being performed in a space less than 283.17 cubic meters per welder. – A room ceiling height less than 1.83 meters. – A confined space or welding space contains partitions, balconies or other structural barriers to the extent that obstruct cross ventilation. The minimum rate for mechanical ventilation will be 56.63 cubic meters per minute per welder unless exhaust hoods or air supplied respirators are provided. When using local exhaust hoods, they will be as close to the operation as possible. The exhaust hood will provide a rate of 30.48 linear meters per minute of air flow in the welding zone. Air-supplied respirators will be used when mechanical ventilating is not possible or when materials such as beryllium and cadmium are used. Local exhaust ventilation or air-supplied respirators will be used when welding or torch cutting on coated metals indoors or in confined spaces. Outdoors operations shall be done using respiratory protective equipment.

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PART III WORKER SAFETY RULES CONTENTS 3(a) Critical Incident Stress ................................................................................................... III-5 3(a)(1) Responding to Emergency Events ............................................................................. III-5 3(a)(2) Critical Incident Stress Management......................................................................... III-5 3(a)(3) Critical Incident Stress Debriefing ............................................................................ III-6 3(b) Toxic Industrial Chemicals ............................................................................................ III-6 3(c) Electrical Protective Devices .......................................................................................... III-9 3(c)(1) Design Requirements................................................................................................. III-9 3(c)(2) Manufacture and Markings........................................................................................ III-9 3(c)(3) Electrical Requirements........................................................................................... III-10 3(c)(4) Workmanship and Finish ......................................................................................... III-10 3(c)(5) In-Service Care and Use .......................................................................................... III-11 3(d) Hand Protection ............................................................................................................ III-15 3(e) Hazard Assessment and Personal Protective Equipment Selection.......................... III-15 3(e)(1) General Guidance .................................................................................................... III-15 3(e)(2) Head Protection........................................................................................................ III-19 3(e)(3) Foot Protection......................................................................................................... III-19 3(e)(4) Hand Protection ....................................................................................................... III-20 3(e)(5) Cleaning and Maintenance....................................................................................... III-20 3(f) Sanitation ........................................................................................................................ III-21 3(f)(1) Definitions................................................................................................................ III-21 3(f)(2) Housekeeping ........................................................................................................... III-21 3(f)(3) Waste Disposal......................................................................................................... III-22 3(f)(4) Water Supply............................................................................................................ III-22 3(f)(4)(i) Potable Water ................................................................................................... III-22 3(f)(4)(ii) Nonpotable Water............................................................................................ III-22 3(f)(5) Toilet Facilities......................................................................................................... III-23 3(f)(6) Construction of Toilet Rooms .................................................................................. III-23 3(f)(7) Washing Facilities .................................................................................................... III-23 3(f)(8) Showers .................................................................................................................... III-24 3(f)(9) Change Rooms ......................................................................................................... III-24 3(f)(10) Clothes Drying Facilities........................................................................................ III-24 3(f)(11) Consumption of Food and Beverages .................................................................... III-24 3(f)(12) Waste Disposal Containers..................................................................................... III-24 3(f)(13) Sanitary Storage ..................................................................................................... III-24 3(f)(14) Food Handling........................................................................................................ III-25 3(g) Safety Color Code for Marking Physical Hazards..................................................... III-25 3(h) Specifications for Accident Prevention Signs and Tags ............................................ III-25 3(h)(1) General..................................................................................................................... III-25 3(h)(2) Classification of Signs ............................................................................................. III-25 3(h)(3) Sign Design.............................................................................................................. III-26

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3(h)(3)(i) Danger Signs.................................................................................................... III-26 3(h)(3)(ii) Caution Signs.................................................................................................. III-26 3(h)(3)(iii) Sign Wordings ............................................................................................... III-26 3(h)(4) Biological Hazard Signs .......................................................................................... III-26 3(h)(5) Accident Prevention Tags........................................................................................ III-27 3(i) Permits for Confined Spaces ......................................................................................... III-28 3(i)(1) Definitions ................................................................................................................ III-28 3(i)(2) General Comments and Requirements ..................................................................... III-31 3(i)(3) Oxygen Content, Flammable Gases and Vapors, and Potential Toxic Air Contaminants............................................................................................ III-32 3(i)(4) Permit Space Program .............................................................................................. III-34 3(i)(4)(i) General Details ................................................................................................. III-34 3(i)(4)(ii) Attendant ......................................................................................................... III-36 3(i)(4)(iii) The Permit System ......................................................................................... III-37 3(i)(4)(iv) Entry Permit.................................................................................................... III-37 3(i)(4)(v) Training............................................................................................................ III-38 3(i)(4)(vi) Duties of Authorized Entrants ........................................................................ III-38 3(i)(4)(vii) Duties of Attendants ...................................................................................... III-39 3(i)(4)(viii) Duties of Entry Supervisors.......................................................................... III-40 3(i)(4)(ix) Rescue and Emergency Services .................................................................... III-40 3(i)(4)(x) Employee Participation.................................................................................... III-41 3(i)(4)(xi)Procedures for Atmospheric Testing ............................................................... III-42 3(j) Control of Hazardous Energy (Lockout/Tagout)........................................................ III-42 3(j)(1) General Information ................................................................................................. III-42 3(j)(2) Definitions ................................................................................................................ III-43 3(j)(3) Elements of Lockout/Tagout .................................................................................... III-45 3(j)(4) Full Employee Protection ......................................................................................... III-45 3(j)(5) Energy Control Procedure ........................................................................................ III-45 3(j)(6) Protective Materials and Hardware .......................................................................... III-45 3(j)(7) Inspection ................................................................................................................. III-46 3(j)(8) Training and Communication................................................................................... III-47 3(j)(9) Energy Isolation........................................................................................................ III-48 3(j)(10) Group Lockout or Tagout....................................................................................... III-49 3(k) Medical Services and First Aid .................................................................................... III-50 3(l) Fire Protection................................................................................................................ III-50 3(l)(1) Fire Brigades ............................................................................................................ III-50 3(l)(2) Fire Fighting Equipment........................................................................................... III-53 3(m) Handling Materials ...................................................................................................... III-56 3(n) Slings .............................................................................................................................. III-57 3(o) Bibliography .................................................................................................................. III-62 Annex A Accident Investigation .......................................................................................... III-65 Annex B Electrical Switching Operation.......................................................................... III-153 Annex C Temporary Protective Grounding for Generating Stations and Other Non-Transmission Facilities .............................................................................. III-157 Annex D Guarding Energized Electrical Equipment ...................................................... III-179 Annex E Jumpers................................................................................................................ III-183

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Annex F Portable Electric Tools and Attachments ........................................................ III-187 Annex G Safe Distribution Systems .................................................................................. III-195 Annex H Temporary Lighting ........................................................................................... III-199 Annex I Vehicle Operations Near Energized Lines or Equipment ................................ III-203 Annex J Responsibilities and General Requirements for Transmission Employees.... III-209 Annex K Transmission/Substation/Telecommunication................................................. III-223 Annex L Specifications and Drawings for Underground Electric Distribution............ III-275

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3(a) Critical Incident Stress 3(a)(1) Responding to Emergency Events Workers responding to emergency events and or disasters will see and experience events that will strain their ability to function. These events, which include having to witness or experience tragedy, death, serious injuries and threatening situations are called "Critical Incidents." The physical and psychological well-being of those experiencing this stress, as well as their future ability to function through a prolonged response, will depend upon how they manage this stress. Post Traumatic Stress Disorder differs from critical incident stress by lasting longer than four weeks after the event triggering the emotional, mental or physical response. Most instances of critical incident stress last between two days and four weeks. The signs and symptoms of critical incident stress can be physical, emotional, cognitive, or behavioral. Individuals express stress in different ways and therefore manifest different reactions. Table 1 below is not exhaustive but will help supervisors to identify workers who are exhibiting stress reactions. Table 1. Signs and Symptoms of Stress

PHYSICAL Fatigue Chills Unusual thirst Chest pain Headaches Dizziness

COGNITIVE Uncertainty Confusion Nightmares Poor attention/ decision making ability Poor concentration, memory Poor problem solving ability

EMOTIONAL Grief Fear Guilt Intense anger Apprehension and depression Irritability Chronic anxiety

BEHAVIORAL Inability to rest Withdrawal Antisocial behavior Increased alcohol consumption Change in communications Loss/increase in appetite

During the emergency phase of the response, monitoring of employees by simple conversation and observation may help to identify early signs for some responders. The following steps can help to reduce significant stress detected early in the response: • • • • • •

Limit exposure to noise and odors. Dictate an immediate 15 minute rest break. Provide non-caffeinated fluids to drink. Provide low sugar and low fat food. Get the person to talk about his or her feelings. Do not rush the person back to work.

3(a)(2) Critical Incident Stress Management Critical Incident Stress Management is system of education, prevention and mitigation of the effects from exposure to highly stressful critical incidents. It is handled most effectively by specially trained individuals, such as crisis intervention specialists.

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3(a)(3) Critical Incident Stress Debriefing Critical Incident Stress Debriefing (CISD) is a facilitator-led group process conducted soon after a traumatic event with individuals considered to be under stress from trauma exposure. When structured, the process usually (but not always) consists of seven steps: • • • • • • •

Introduction; Fact Phase; Thought Phase; Reaction Phase; Symptom Phase; Teaching Phase; and Re-entry Phase.

During the group process, participants are encouraged to describe their experience of the incident and its aftermath, followed by a presentation on common stress reactions and stress management. This early intervention process supports recovery by providing group support and linking employees to further counseling and treatment services if they become necessary. 3(b) Toxic Industrial Chemicals Toxic industrial chemicals are industrial chemicals that are manufactured, stored, transported, and used throughout the world. Toxic industrial chemicals can be in the gas, liquid, or solid state. They can be chemical hazards (e.g., carcinogens, reproductive hazards, corrosives, or agents that affect the lungs or blood) or physical hazards (e.g., flammable, combustible, explosive, or reactive). Table 2 lists the most common TICs listed by their hazard index. Table 2. TICs Listed by Hazard Index

High Ammonia (CAS# 7664-41-7) Arsine (CAS# 7784-42-1) Boron trichloride (CAS#10294-34-5) Boron trifluoride (CAS#7637-07-2) Carbon disulfide (CAS# 75-15-0) Chlorine (CAS# 7782-50-5) Diborane (CAS# 19287-45-7) Ethylene oxide (CAS# 75-21-8) III-6

Medium Acetone cyanohydrin (CAS# 75-86-5) Acrolein (CAS# 107-02-8) Acrylonitrile (CAS# 107-13-l) Allyl alcohol (CAS# 107-18-6) Allylamine (CAS# 107-11-9) Allyl chlorocarbonate (CAS# 2937-50-0) Boron tribromide (CAS# 10294-33-4) Carbon monoxide (CAS# 630-08-0)

Low Allyl isothiocyanate (CAS# 57-06-7) Arsenic trichloride (CAS# 7784-34-1) Bromine (CAS# 7726-95-6) Bromine chloride (CAS# 13863-41-7) Bromine pentafluoride (CAS# 7789-30-2) Bromine trifluoride (CAS# 7787-71-5) Carbonyl fluoride (CAS# 353-50-4) Chlorine pentafluoride (CAS# 13637-63-3)

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High Fluorine (CAS# 7782-41-4) Formaldehyde (CAS# 50-00-0) Hydrogen bromide (CAS# 10035-10-6) Hydrogen chloride (CAS# 7647-01-0) Hydrogen cyanide (CAS#74-90-8) Hydrogen fluoride (CAS# 7664-39-3) Hydrogen sulfide (CAS# 7783-0604) Nitric acid, fuming (CAS# 7697-37-2) Phosgene (CAS# 75-44-5) Phosphorus trichloride (CAS# 7719-12-2) Sulfur dioxide (CAS# 7446-09-5) Sulfuric acid (CAS# 7664-93-9) Tungsten hexafluoride (CAS# 7783-82-6)

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Medium Carbonyl sulfide (CAS# 463-58-1) Chloroacetone (CAS# 78-95-5) Chloroacetonitrile (CAS# 7790-94-5) Chlorosulfonic acid (CAS# 7790-94-5) Diketene (CAS# 674-82-8) 1,2-Dimethylhydrazine (CAS# 540-73-8) Ethylene dibromide (CAS# 106-93-4) Hydrogen selenide (CAS# 7783-07-5) Methanesulfonyl chloride (CAS# 124-63-0) Methyl bromide (CAS# 74-83-9) Methyl chloroformate (CAS# 79-22-1) Methyl chlorosilane (CAS# 993-00-0) Methyl hydrazine (CAS# 60-34-4) Methyl isocyanate (CAS# 624-83-9) Methyl mercaptan (CAS# 74-93-1) Nitrogen dioxide (CAS# 10102-44-0) Phosphine (CAS# 7803-51-2) Phosphorus oxychloride (CAS# 10025-87-3) Phosphorus pentafluoride (CAS# 7647-19-0) Selenium hexafluoride (CAS# 7783-79-1)

Low Chlorine trifluoride (CAS# 7790-91-2) Chloroacetaldehyde (CAS# 107-20-0) Chloroacetyl chloride (CAS# 79-04-9) Crotonaldehyde (CAS# 123-73-9) Cyanogen chloride (CAS# 506-77-4) Dimethyl sulfate (CAS# 77-78-1) Diphenylmethane-4.4'diisocyanate (CAS# 101-68-8) Ethyl chlroroformate (CAS# 541-41-3) Ethyl chlorothioformate (CAS# 2941-64-2) Ethyl phosphonothioic dichloride (CAS# 993–43–1) Ethyl phosphonic dichloride (CAS# 1066-50-8) Ethyleneimine (CAS# 151-56-4) Hexachlorocyclopentadiene (CAS# 77-47-4) Hydrogen iodide (CAS# 10034-85-2) Iron pentacarbonyl (CAS# 13463-40-6) Isobutyl chloroformate (CAS# 543-27-1) Isopropyl chloroformate (CAS# 108-23-6) Isopropyl isocyanate (CAS# 1795-48-8) n-Butyl chloroformate (CAS# 592-34-7) n-Butyl isocyanate (CAS# 111-36-4) III-7

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Medium Silicon tetrafluoride (CAS# 7783-61-1) Stibine (CAS# 7803-52-3) Sulfur trioxide (CAS# 7446-11-9) Sulfuryl fluoride (CAS# 2699-79-8) Tellurium hexafluoride (CAS# 7783-80-4) n-Octyl mercaptan (CAS# 111-88-6) Titanium tetrachloride (CAS# 7550-45-0) Tricholoroacetyl chloride (CAS# 76-02-8) Trifluoroacetyl chloride (CAS# 354-32-5)

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Low Nitric oxide (CAS# 10102-43-9) n-Propyl chloroformate (CAS# 109-61-5) Parathion (CAS#: 56-38-2) Perchloromethyl mercaptan (CAS# 594-42-3) sec-Butyl chloroformate (CAS# 17462-58-7) tert-Butyl isocyanate (CAS# 1609-86-5) Tetraethyl lead (CAS# 78-00-2) Tetraethyl pyrophosphate (CAS# 107-49-3) Tetramethyl lead (CAS# 75-74-1) Toluene 2.4-diisocyanate (CAS# 584-84-9) Toluene 2.6-diisocyanate (CAS# 91-08-7)

Source: Guide for the Selection of Chemical and Biological Decontamination Equipment for Emergency First Responders. National Institute of Justice Guide 103-00 (Volume I), (2001, October). This guide for emergency first responders provides information about the selection and use of chemical and/or biological decontamination equipment for various applications.

The time that these agents persist in the environment is dependent on many variables such as physical state (solid, liquid, or gas), weather conditions (wind speed, rain or snow, air or surface temperature), indoor or outdoor release, chemical stability, method of release (vapor or aerosol), or quantity released. Many toxic industrial chemicals are highly toxic and may rapidly affect exposed individuals. Toxic industrial chemicals (whether as a gas, aerosol, or liquid) enter the body through inhalation, through the skin, or through digestion. The time that it takes for a toxic industrial chemical to begin working is dependent mainly on the route that the agent enters the body. Generally poisoning occurs more quickly if a chemical enters through the lungs (because of the ability of the agent to rapidly diffuse throughout the body). Information related to how the chemicals affect humans and symptoms of exposure to specific chemicals can be found in material safety data sheets (MSDS) or chemical information cards. If you are exposed to a toxic industrial chemicals attack, get away from the impacted area quickly without passing through the contaminated area, if possible. If available, a good way to III-8

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protect yourself from a toxic industrial chemicals is to wear suitable chemical protective clothing and respiratory protection. However, it must be stressed that this protective equipment does not always work against toxic industrial chemicals. The effectiveness is determined by the materials of construction, the type and level of exposure, and duration of exposure. If you have been exposed to a toxic industrial chemical, consult with your physician as soon as possible. Personal decontamination can be performed by removing contaminated clothing and washing exposed skin with soap and water. "Shelter-in-place" means to go indoors, close up the building, and wait for the danger to pass. If you are advised to shelter in place, close all doors and windows; turn off fans, air conditioners, and forced-air heating units that bring in fresh air from the outside; only re-circulate air that is already in the building; move to an inner room or basement; and keep your radio turned to the emergency response network or local news to find out what else you need to do. First responders should consider the possible impact of a release of toxic industrial chemicals and address these in their health and safety plans (HASPs). The health and safety plan should include guidelines such as monitoring, detection, awareness training, personal protective equipment, decontamination, and medical surveillance of acutely exposed workers. There are a wide variety of direct reading instruments and analytical sampling and analysis procedures available for detecting toxic industrial chemicals. Direct reading instruments include detector tubes, flame ionization detector (FID), photoionization detector (PID), and specialized gas chromatographs. During a chemical release, or after a release has occurred with no information available about the duration of the release or the airborne concentration of toxic industrial chemicals, at a minimum, Level B protection should be used. The requirement of OSHA’s Hazardous Waste Operations and Emergency Response (HAZWOPER) standard (29 CFR 1910.120(q)) provides additional information for responding to hazardous substance releases including toxic industrial chemicals. 3(c) Electrical Protective Devices 3(c)(1) Design Requirements Insulating blankets, matting, covers, line hose, gloves, and sleeves made of rubber shall meet the following requirements: •

Blankets, gloves, and sleeves shall be produced by a seamless process.

3(c)(2) Manufacture and Markings •

•

Each item shall be clearly marked as follows: – Class 0 equipment shall be marked Class 0. – Class 1 equipment shall be marked Class 1. – Class 2 equipment shall be marked Class 2. – Class 3 equipment shall be marked Class 3. – Class 4 equipment shall be marked Class 4. Non-ozone-resistant equipment other than matting shall be marked Type I. III-9

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Ozone-resistant equipment other than matting shall be marked Type II. Other relevant markings, such as the manufacturer's identification and the size of the equipment, may also be provided. Markings shall be non-conducting and shall be applied in such a manner as not to impair the insulating qualities of the equipment. Markings on gloves shall be confined to the cuff portion of the glove.

3(c)(3) Electrical Requirements Equipment shall be capable of withstanding the a-c proof-test voltage specified in Table 3 or the d-c proof-test voltage specified in Table 4. The proof test shall reliably indicate that the equipment can withstand the voltage involved. The test voltage shall be applied continuously for 3 minutes for equipment other than matting and shall be applied continuously for 1 minute for matting. Gloves shall also be capable of withstanding the a-c proof-test voltage specified in Table 3 after a 16-hour water soak. When the a-c proof test is used on gloves, the 60-hertz proof-test current may not exceed the values specified in Table 3 at any time during the test period. If the a-c proof test is made at a frequency other than 60 hertz, the permissible proof-test current shall be computed from the direct ratio of the frequencies. For the test, gloves (right side out) shall be filled with tap water and immersed in water to a depth that is in accordance with Table 5. Water shall be added to or removed from the glove, as necessary, so that the water level is the same inside and outside the glove. After the 16-hour water soak specified in paragraph (a)(2)(i)(C) of this section, the 60-hertz proof-test current may exceed the values given in Table 3 by not more than 2 milliamperes. Equipment that has been subjected to a minimum breakdown voltage test may not be used for electrical protection. Material used for Type II insulating equipment shall be capable of withstanding an ozone test, with no visible effects. The ozone test shall reliably indicate that the material will resist ozone exposure in actual use. Any visible signs of ozone deterioration of the material, such as checking, cracking, breaks, or pitting, is evidence of failure to meet the requirements for ozone-resistant material. 3(c)(4) Workmanship and Finish Equipment shall be free of harmful physical irregularities that can be detected by the tests or inspections required under this section.

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Surface irregularities that may be present on all rubber goods because of imperfections on forms or molds or because of inherent difficulties in the manufacturing process and that may appear as indentations, protuberances, or imbedded foreign material are acceptable under the following conditions: • •

The indentation or protuberance blends into a smooth slope when the material is stretched. Foreign material remains in place when the insulating material is folded and stretches with the insulating material surrounding it.

The following are important reference materials: • • • • • •

American Society for Testing and Materials (ASTM) D 120-87, Specification for Rubber Insulating Gloves. ASTM D 178-93 (or D 178-88), Specification for Rubber Insulating Matting. ASTM D 1048-93 (or D 1048-88a), Specification for Rubber Insulating Blankets. ASTM D 1049-93 (or D 1049-88), Specification for Rubber Insulating Covers. ASTM D 1050-90, Specification for Rubber Insulating Line Hose. ASTM D 1051-87, Specification for Rubber Insulating Sleeves.

These standards contain specifications for conducting the various tests required in paragraph (a) of this section. For example, the a-c and d-c proof tests, the breakdown test, the water soak procedure, and the ozone test mentioned in this paragraph are described in detail in the ASTM standards. 3(c)(5) In-Service Care and Use Electrical protective equipment shall be maintained in a safe, reliable condition. The following specific requirements apply to insulating blankets, covers, line hose, gloves, and sleeves made of rubber: • • •

Maximum use voltages shall conform to those listed in Table 6. Insulating equipment shall be inspected for damage before each day's use and immediately following any incident that can reasonably be suspected of having caused damage. Insulating gloves shall be given an air test, along with the inspection. Insulating equipment with any of the following defects may not be used: – A hole, tear, puncture, or cut; – Ozone cutting or ozone checking (the cutting action produced by ozone on rubber under mechanical stress into a series of interlacing cracks); – An embedded foreign object; – Any of the following texture changes: swelling, softening, hardening, or becoming sticky or inelastic; – Any other defect that damages the insulating properties.

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Insulating equipment found to have other defects that might affect its insulating properties shall be removed from service and returned for testing. Insulating equipment shall be cleaned as needed to remove foreign substances. Insulating equipment shall be stored in such a location and in such a manner as to protect it from light, temperature extremes, excessive humidity, ozone, and other injurious substances and conditions. Protector gloves shall be worn over insulating gloves, except as follows: • •

Protector gloves need not be used with Class 0 gloves, under limited-use conditions, where small equipment and parts manipulation necessitate unusually high finger dexterity. Note: Extra care is needed in the visual examination of the glove and in the avoidance of handling sharp objects.

Any other class of glove may be used for similar work without protector gloves if the employer can demonstrate that the possibility of physical damage to the gloves is small and if the class of glove is one class higher than that required for the voltage involved. Insulating gloves that have been used without protector gloves may not be used at a higher voltage until they have been tested. Electrical protective equipment shall be subjected to periodic electrical tests. Test voltages and the maximum intervals between tests shall be in accordance with Tables 6 and 7. The test method used shall reliably indicate whether the insulating equipment can withstand the voltages involved. Note: Standard electrical test methods considered as meeting this requirement are given in the following national consensus standards: • • • • • • • •

American Society for Testing and Materials (ASTM) D 120-87, Specification for Rubber Insulating Gloves. ASTM D 1048-93, Specification for Rubber Insulating Blankets. ASTM D 1049-93, Specification for Rubber Insulating Covers. ASTM D 1050-90, Specification for Rubber Insulating Line Hose. ASTM D 1051-87, Specification for Rubber Insulating Sleeves. ASTM F 478-92, Specification for In-Service Care of Insulating Line Hose and Covers. ASTM F 479-93, Specification for In-Service Care of Insulating Blankets. ASTM F 496-93b, Specification for In-Service Care of Insulating Gloves and Sleeves.

Insulating equipment failing to pass inspections or electrical tests may not be used by employees, except as follows:

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Rubber insulating line hose may be used in shorter lengths with the defective portion cut off. Rubber insulating blankets may be repaired using a compatible patch that results in physical and electrical properties equal to those of the blanket. Rubber insulating blankets may be salvaged by severing the defective area from the undamaged portion of the blanket. The resulting undamaged area may not be smaller than 560 mm by 560 mm for Class 1, 2, 3, and 4 blankets.

Rubber insulating gloves and sleeves with minor physical defects, such as small cuts, tears, or punctures, may be repaired by the application of a compatible patch. Also, rubber insulating gloves and sleeves with minor surface blemishes may be repaired with a compatible liquid compound. The patched area shall have electrical and physical properties equal to those of the surrounding material. Repairs to gloves are permitted only in the area between the wrist and the reinforced edge of the opening. Repaired insulating equipment shall be retested before it may be used by employees. The employer shall certify that equipment has been tested. The certification shall identify the equipment that passed the test and the date it was tested. Note: Marking of equipment and entering the results of the tests and the dates of testing onto logs are two acceptable means of meeting this requirement. Table 3. A-C Proof-Test Requirements

Maximum proof-test current, mA (gloves only) Class of equipment 0………….. 1………….. 2………….. 3………….. 4…………..

Proof-test voltage rms V 5,000 10,000 20,000 30,000 40,000

267-mm glove

356-mm glove

8 ………….. ………….. ………….. …………..

12 14 16 18 …………..

406-mm glove

457-mm glove 14 16 18 20 22

16 18 20 22 24

Table 4. D-C Proof-Test Requirements

Class of equipment Proof-test voltage 20,000 0…………..…………..…………..………….. 40,000 1…………..…………..…………..………….. 50,000 2…………..…………..…………..………….. 60,000 3…………..…………..…………..………….. 70,000 4…………..…………..…………..………….. Note: The d-c voltages listed in this table are not appropriate for proof testing rubber insulating line hose or covers. For this equipment, d-c proof tests shall use a voltage high enough to indicate that the equipment can be safely used at the voltages listed in ASTM D Standards 105090 and ASTM D 1049-88. III-13

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Table 5. Glove Tests - Water Level(1)(2)

Class of glove 0.................. 1.................. 2.................. 3.................. 4..................

AC proof test

DC proof test

mm. 38 38 64 89 127

mm. 38 51 76 102 153

Footnote(1) The water level is given as the clearance from the cuff of the glove to the water line, with a tolerance of + or - 13 mm. (+ or - 0.5 in.). Footnote(2) If atmospheric conditions make the specified clearances impractical, the clearances may be increased by a maximum of 25 mm. (1 in.). Table 6. Rubber Insulating Equipment Voltage Requirements

Class of equipment

0.................. 1.................. 2.................. 3.................. 4..................

Maximum use voltage (1) a – c – rms 1,000 7,000 17,000 26,000 36,000

Retest voltage (2) a – c – rms 5,000 10,000 20,000 30,000 40,000

Retest voltage (2) d – c – avg 20,000 40,000 50,000 60,000 70,000

Footnote(1) The maximum use voltage is the a-c voltage (rms) classification of the protective equipment that designates the maximum nominal design voltage of the energized system that may be safely worked. The nominal design voltage is equal to the phase-to-phase voltage on multiphase circuits. However, the phase-to-ground potential is considered to be the nominal design voltage:

[1] If there is no multiphase exposure in a system area and if the voltage exposure is limited to the phase-to-ground potential, or [2] If the electrical equipment and devices are insulated or isolated or both so that the multiphase exposure on a grounded wire circuit is removed. Footnote(2) The proof-test voltage shall be applied continuously for at least 1 minute, but no more than 3 minutes.

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Table 7. Rubber Insulating Equipment Test Intervals

Type of equipment

When to test

Rubber insulating line hose Upon indication that insulating value is suspect. Rubber insulating covers

Upon indication that insulating value is suspect.

Rubber insulating blankets

Before first issue and every 12 months thereafter(1).

Rubber insulating gloves

Before first issue and every 6 months thereafter(1).

Rubber insulating sleeves

Before first issue and every 12 months thereafter(1).

Footnote(1) If the insulating equipment has been electrically tested but not issued for service, it may not be placed into service unless it has been electrically tested within the previous 12 months.

3(d) Hand Protection Employers shall select and require employees to use appropriate hand protection when employees' hands are exposed to hazards such as those from skin absorption of harmful substances; severe cuts or lacerations; severe abrasions; punctures; chemical burns; thermal burns; and harmful temperature extremes. Employers shall base the selection of the appropriate hand protection on an evaluation of the performance characteristics of the hand protection relative to the task(s) to be performed, conditions present, duration of use, and the hazards and potential hazards identified. 3(e) Hazard Assessment and Personal Protective Equipment Selection 3(e)(1) General Guidance The following guidelines will assist employers and employees in implementing requirements for a hazard assessment and the selection of personal protective equipment. 1. Controlling hazards. PPE devices alone should not be relied on to provide protection against hazards, but should be used in conjunction with guards, engineering controls, and sound manufacturing practices. 2. Assessment and selection. It is necessary to consider certain general guidelines for assessing the foot, head, eye and face, and hand hazard situations that exist in an occupational or educational operation or process, and to match the protective devices to the particular hazard. It should be the responsibility of the safety officer to exercise common sense and appropriate expertise to accomplish these tasks. 3. Assessment guidelines. In order to assess the need for PPE the following steps should be taken: a. Survey. Conduct a walk-through survey of the areas in question. The purpose of the survey is to identify sources of hazards to workers and co-workers. Consideration should be given to the basic hazard categories: i. Impact; ii. Penetration; iii. Compression (roll-over); iv. Chemical; v. Heat; III-15

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vi. Harmful dust; and vii. Light (optical) radiation. b. Sources. During the walk-through survey the safety officer should observe: i. sources of motion; i.e., machinery or processes where any movement of tools, machine elements or particles could exist, or movement of personnel that could result in collision with stationary objects; ii. sources of high temperatures that could result in burns, eye injury or ignition of protective equipment, etc.; iii. types of chemical exposures; iv. sources of harmful dust; v. sources of light radiation, i.e., welding, brazing, cutting, furnaces, heat treating, high intensity lights, etc.; vi. sources of falling objects or potential for dropping objects; vii. sources of sharp objects which might pierce the feet or cut the hands; viii. sources of rolling or pinching objects which could crush the feet; and ix. layout of workplace and location of co-workers. In addition, injury/accident data should be reviewed to help identify problem areas. c. Organize data. Following the walk-through survey, it is necessary to organize the data and information for use in the assessment of hazards. The objective is to prepare for an analysis of the hazards in the environment to enable proper selection of protective equipment. d. Analyze data. Having gathered and organized data on a workplace, an estimate of the potential for injuries should be made. Each of the basic hazards (paragraph 3.a.) should be reviewed and a determination made as to the type, level of risk, and seriousness of potential injury from each of the hazards found in the area. The possibility of exposure to several hazards simultaneously should be considered. 4. Selection guidelines. After completion of the procedures in paragraph 3, the general procedure for selection of protective equipment is to: a. Become familiar with the potential hazards and the type of protective equipment that is available, and what it can do; i.e., splash protection, impact protection, etc.; b. compare the hazards associated with the environment; i.e., impact velocities, masses, projectile shape, radiation intensities, with the capabilities of the available protective equipment; c. select the protective equipment which ensures a level of protection greater than the minimum required to protect employees from the hazards; and d. fit the user with the protective device and give instructions on care and use of the PPE. It is very important that end users be made aware of all warning labels for and limitations of their PPE. 5. Fitting the device. Careful consideration must be given to comfort and fit. PPE that fits poorly will not afford the necessary protection. Continued wearing of the device is more likely if it fits the wearer comfortably. Protective devices are generally available in a variety of sizes. Care should be taken to ensure that the right size is selected. 6. Devices with adjustable features. Adjustments should be made on an individual basis for a comfortable fit that will maintain the protective device in the proper position. Particular care should be taken in fitting devices for eye protection against dust and chemical splash to ensure that the devices are sealed to the face. In addition, proper fitting of helmets is

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important to ensure that it will not fall off during work operations. In some cases a chin strap may be necessary to keep the helmet on an employee's head. (Chin straps should break at a reasonably low force, however, so as to prevent a strangulation hazard). Where manufacturer's instructions are available, they should be followed carefully. 7. Reassessment of hazards. It is the responsibility of the safety officer to reassess the workplace hazard situation as necessary, by identifying and evaluating new equipment and processes, reviewing accident records, and reevaluating the suitability of previously selected PPE. 8. Selection chart guidelines for eye and face protection. Some occupations (not a complete list) for which eye protection should be routinely considered are: carpenters, electricians, machinists, mechanics and repairers, millwrights, plumbers and pipe fitters, sheet metal workers and tinsmiths, assemblers, sanders, grinding machine operators, lathe and milling machine operators, sawyers, welders, laborers, chemical process operators and handlers, and timber cutting and logging workers. Table 8 chart provides general guidance for the proper selection of eye and face protection to protect against hazards associated with the listed hazard "source" operations. Table 8. Eye and Face Protection Chart

Source

Assessment of Hazard

Protection

IMPACT - Chipping, grinding machining, masonry work, woodworking, sawing, drilling, chiseling, powered fastening, riveting, and sanding.

Flying fragments, objects, large chips, particles sand, dirt, etc. .....

Spectacles with side protection, goggles, face shields. See notes (1), (3), (5), (6), (10). For severe exposure, use faceshield.

HEAT - Furnace operations, pouring, casting, hot dipping, and welding.

Hot sparks .....

Faceshields, goggles, spectacles with side protection. For severe exposure use faceshield. See notes (1), (2), (3).

Splash from molten metals .....

Faceshields worn over goggles. See notes (1), (2), (3).

High temperature exposure .....

Screen face shields, reflective face shields. See notes (1), (2), (3).

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Source

Assessment of Hazard

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Protection

Splash .....

Goggles, eyecup and cover types. For severe exposure, use face shield. See notes (3), (11).

Irritating mists .....

Special-purpose goggles.

Nuisance dust .....

Goggles, eyecup and cover types. See note (8).

LIGHT and/or RADIATION Welding: Electric arc

Optical radiation .....

Welding helmets or welding shields. Typical shades: 10-14. See notes (9), (12).

Welding: Gas

Optical radiation .....

Welding goggles or welding face shield. Typical shades: gas welding 4-8, cutting 3-6, brazing 3-4. See note (9).

Cutting, Torch brazing, Torch soldering

Optical radiation .....

Spectacles or welding face shield. Typical shades, 1.5-3. See notes (3), (9).

Glare

Poor vision .....

Spectacles with shaded or special-purpose lenses, as suitable. See notes (9), (10).

CHEMICALS - Acid and chemicals handling, degreasing plating.

DUST - Woodworking, buffing, general dusty conditions.

Notes to Eye and Face Protection Selection Chart: (1) Care should be taken to recognize the possibility of multiple and simultaneous exposure to a variety of hazards. Adequate protection against the highest level of each of the hazards should be provided. Protective devices do not provide unlimited protection. (2) Operations involving heat may also involve light radiation. As required by the standard, protection from both hazards must be provided. (3) Face shields should only be worn over primary eye protection (spectacles or goggles). (4) As required by the standard, filter lenses must meet the requirements for shade designations in 1910.133(a)(5). Tinted and shaded lenses are not filter lenses unless they are marked or identified as such. (5) As required by the standard, persons whose vision requires the use of prescription (Rx) lenses must wear either protective devices fitted with prescription (Rx) lenses or protective devices designed to be worn over regular prescription (Rx) eyewear. (6) Wearers of contact lenses must also wear appropriate eye and face protection devices in a hazardous environment. It should be recognized that dusty and/or chemical environments may represent an additional hazard to contact lens wearers. (7) Caution should be exercised in the use of metal frame protective devices in electrical hazard areas. (8) Atmospheric conditions and the restricted ventilation of the protector can cause lenses to fog. Frequent cleansing may be necessary. (9) Welding helmets or face shields should be used only over primary eye protection (spectacles or goggles).

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(10) Non-side shield spectacles are available for frontal protection only, but are not acceptable eye protection for the sources and operations listed for "impact." (11) Ventilation should be adequate, but well protected from splash entry. Eye and face protection should be designed and used so that it provides both adequate ventilation and protects the wearer from splash entry. (12) Protection from light radiation is directly related to filter lens density. See note (4) . Select the darkest shade that allows task performance.

3(e)(2) Head Protection Head protection (helmets) is designed to provide protection from impact and penetration hazards caused by falling objects. Head protection is also available which provides protection from electric shock and burn. When selecting head protection, knowledge of potential electrical hazards is important. Class A helmets, in addition to impact and penetration resistance, provide electrical protection from low-voltage conductors (they are proof tested to 2,200 volts). Class B helmets, in addition to impact and penetration resistance, provide electrical protection from highvoltage conductors (they are proof tested to 20,000 volts). Class C helmets provide impact and penetration resistance (they are usually made of aluminum which conducts electricity), and should not be used around electrical hazards. Where falling object hazards are present, helmets must be worn. Some examples include: working below other workers who are using tools and materials which could fall; working around or under conveyor belts which are carrying parts or materials; working below machinery or processes which might cause material or objects to fall; and working on exposed energized conductors. Some examples of occupations for which head protection should be routinely considered are: carpenters, electricians, linemen, mechanics and repairers, plumbers and pipe fitters, assemblers, packers, wrappers, sawyers, welders, laborers, freight handlers, timber cutting and logging, stock handlers, and warehouse laborers. 3(e)(3) Foot Protection Safety shoes and boots which meet the ANSI Z41-1991 Standard provide both impact and compression protection. Where necessary, safety shoes can be obtained which provide puncture protection. In some work situations, metatarsal protection should be provided, and in other special situations electrical conductive or insulating safety shoes would be appropriate. Safety shoes or boots with impact protection would be required for carrying or handling materials such as packages, objects, parts or heavy tools, which could be dropped; and, for other activities where objects might fall onto the feet. Safety shoes or boots with compression protection would be required for work activities involving skid trucks (manual material handling carts) around bulk rolls (such as paper rolls) and around heavy pipes, all of which could potentially roll over an employee's feet. Safety shoes or boots with puncture protection would be required where sharp objects such as nails, wire, tacks, screws, large staples, scrap metal etc., could be stepped on by employees causing a foot injury. Some occupations (not a complete list) for which foot protection should be routinely considered are: shipping and receiving clerks, stock clerks, carpenters, electricians, machinists, mechanics and repairers, plumbers and pipe fitters, structural metal workers, assemblers, drywall installers and lathers, packers, wrappers, craters, punch and stamping press operators, sawyers, welders,

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laborers, freight handlers, gardeners and grounds-keepers, timber cutting and logging workers, stock handlers and warehouse laborers. 3(e)(4) Hand Protection Gloves are often relied upon to prevent cuts, abrasions, burns, and skin contact with chemicals that are capable of causing local or systemic effects following dermal exposure. OSHA is unaware of any gloves that provide protection against all potential hand hazards, and commonly available glove materials provide only limited protection against many chemicals. Therefore, it is important to select the most appropriate glove for a particular application and to determine how long it can be worn, and whether it can be reused. It is also important to know the performance characteristics of gloves relative to the specific hazard anticipated; e.g., chemical hazards, cut hazards, flame hazards, etc. These performance characteristics should be assessed by using standard test procedures. Before purchasing gloves, the employer should request documentation from the manufacturer that the gloves meet the appropriate test standard(s) for the hazard(s) anticipated. Other factors to be considered for glove selection in general include: 1. As long as the performance characteristics are acceptable, in certain circumstances, it may be more cost effective to regularly change cheaper gloves than to reuse more expensive types; and 2. The work activities of the employee should be studied to determine the degree of dexterity required, the duration, frequency, and degree of exposure of the hazard, and the physical stresses that will be applied. With respect to selection of gloves for protection against chemical hazards: 1. The toxic properties of the chemical(s) must be determined; in particular, the ability of the chemical to cause local effects on the skin and/or to pass through the skin and cause systemic effects; 2. Generally, any "chemical resistant" glove can be used for dry powders; 3. For mixtures and formulated products (unless specific test data are available), a glove should be selected on the basis of the chemical component with the shortest breakthrough time, since it is possible for solvents to carry active ingredients through polymeric materials; and 4. Employees must be able to remove the gloves in such a manner as to prevent skin contamination. 3(e)(5) Cleaning and Maintenance It is important that all PPE be kept clean and properly maintained. Cleaning is particularly important for eye and face protection where dirty or fogged lenses could impair vision. PPE should be inspected, cleaned, and maintained at regular intervals so that the PPE provides the requisite protection. It is also important to ensure that contaminated PPE which cannot be decontaminated is disposed of in a manner that protects employees from exposure to hazards.

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3(f) Sanitation 3(f)(1) Definitions Non-water carriage toilet facility means a toilet facility not connected to a sewer. Number of employees, unless otherwise specified, means the maximum number of employees present at any one time on a regular shift. Personal service room means a room used for activities not directly connected with the production or service function performed by the establishment. Such activities include, but are not limited to, first-aid, medical services, dressing, showering, toilet use, washing, and eating. Potable water means water which meets the quality standards prescribed in the U.S. Public Health Service Drinking Water Standards, published in 42 CFR Part 72, or water which is approved for drinking purposes by the State or local authority having jurisdiction. Toilet facility means a fixture maintained within a toilet room for the purpose of defecation or urination, or both. Toilet room means a room maintained within or on the premises of any place of employment, containing toilet facilities for use by employees. Toxic material means a material in concentration or amount which exceeds the applicable limit established by a standard, such as 1910.1000 and 1910.1001 or, in the absence of an applicable standard, which is of such toxicity so as to constitute a recognized hazard that is causing or is likely to cause death or serious physical harm. Urinal means a toilet facility maintained within a toilet room for the sole purpose of urination. Water closet means a toilet facility maintained within a toilet room for the purpose of both defecation and urination and which is flushed with water. Wet process means any process or operation in a workroom which normally results in surfaces upon which employees may walk or stand becoming wet. 3(f)(2) Housekeeping All work places shall be kept clean to the extent that the nature of the work allows. The floor of every workroom shall be maintained, so far as practicable, in a dry condition. Where wet processes are used, drainage shall be maintained and false floors, platforms, mats, or other dry standing places shall be provided, where practicable, or appropriate waterproof footgear shall be provided. To facilitate cleaning, every floor, working place, and passageway shall be kept free from protruding nails, splinters, loose boards, and unnecessary holes and openings.

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3(f)(3) Waste Disposal Any receptacle used for putrescible solid or liquid waste or refuse shall be so constructed that it does not leak and may be thoroughly cleaned and maintained in a sanitary condition. Such a receptacle shall be equipped with a solid tight-fitting cover, unless it can be maintained in a sanitary condition without a cover. This requirement does not prohibit the use of receptacles which are designed to permit the maintenance of a sanitary condition without regard to the aforementioned requirements. All sweepings, solid or liquid wastes, refuse, and garbage shall be removed in such a manner as to avoid creating a menace to health and as often as necessary or appropriate to maintain the place of employment in a sanitary condition. Vermin control. Every enclosed workplace shall be so constructed, equipped, and maintained, so far as reasonably practicable, as to prevent the entrance or harborage of rodents, insects, and other vermin. A continuing and effective extermination program shall be instituted where their presence is detected. 3(f)(4) Water Supply 3(f)(4)(i) Potable Water Potable water shall be provided in all places of employment, for drinking, washing of the person, cooking, washing of foods, washing of cooking or eating utensils, washing of food preparation or processing premises, and personal service rooms. Portable drinking water dispensers shall be designed, constructed, and serviced so that sanitary conditions are maintained, shall be capable of being closed, and shall be equipped with a tap. Open containers such as barrels, pails, or tanks for drinking water from which the water must be dipped or poured, whether or not they are fitted with a cover, are prohibited. A common drinking cup and other common utensils are prohibited. 3(f)(4)(ii) Non-potable Water Outlets for non-potable water, such as water for industrial or firefighting purposes, shall be posted or otherwise marked in a manner that will indicate clearly that the water is unsafe and is not to be used for drinking, washing of the person, cooking, washing of food, washing of cooking or eating utensils, washing of food preparation or processing premises, or personal service rooms, or for washing clothes. Construction of non-potable water systems or systems carrying any other non-potable substance shall be such as to prevent backflow or back-siphonage into a potable water system. Non-potable water shall not be used for washing any portion of the person, cooking or eating utensils, or clothing. Non-potable water may be used for cleaning work premises, other than food processing and preparation premises and personal service rooms: Provided that this non-potable

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water does not contain concentrations of chemicals, fecal coliform, or other substances which could create unsanitary conditions or be harmful to employees. 3(f)(5) Toilet Facilities Except as otherwise indicated in toilet rooms separate for each sex, shall be provided in all places of employment in accordance with Table 9 of this section. The number of facilities to be provided for each sex shall be based on the number of employees of that sex for whom the facilities are furnished. Toilet rooms are to be occupied by no more than one person at a time, can be locked from the inside, and contain at least one water closet, separate toilet rooms for each sex need not be provided. Where such single-occupancy rooms have more than one toilet facility, only one such facility in each toilet room shall be counted for the purpose of Table 9. Table 9. Minimum number of water closets

Number of employees 1 to 15 ................. 16 to 35 ............... 36 to 55 ............... 56 to 80 .............. 81 to 110 ............. 111 to 150 ........... Over 150 .............

Minimum number of water closets(1) 1 2 3 4 5 6 (2)

Footnote(1) Where toilet facilities will not be used by women, urinals may be provided instead of water closets, except that the number of water closets in such cases shall not be reduced to less than 2/3 of the minimum specified. Footnote(2) 1 additional fixture for each additional 40 employees.

The requirements of this section do not apply to mobile crews or to normally unattended work locations so long as employees working at these locations have transportation immediately available to nearby toilet facilities which meet the other requirements of this subparagraph. The sewage disposal method shall not endanger the health of employees. 3(f)(6) Construction of Toilet Rooms Each water closet shall occupy a separate compartment with a door and walls or partitions between fixtures sufficiently high to assure privacy. 3(f)(7) Washing Facilities Washing facilities shall be maintained in a sanitary condition. Lavatories shall be made available in all places of employment. The requirements of this subdivision do not apply to mobile crews or to normally unattended work locations if employees working at these locations have transportation readily available to nearby washing facilities which meet the other requirements of this paragraph. Each lavatory shall be provided with hot and cold running water, or tepid running water.

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Hand soap or similar cleansing agents shall be provided. Individual hand towels or sections thereof, of cloth or paper, warm air blowers or clean individual sections of continuous cloth toweling, convenient to the lavatories, shall be provided. 3(f)(8) Showers Whenever showers are required the following guidelines are recommended: • • • •

One shower shall be provided for each 10 employees of each sex, or numerical fraction thereof, who are required to shower during the same shift. Body soap or other appropriate cleansing agents convenient to the showers shall be provided as specified in paragraph (d)(2)(iii) of this section. Showers shall be provided with hot and cold water feeding a common discharge line. Employees who use showers shall be provided with individual clean towels.

3(f)(9) Change Rooms Whenever employees are required by a particular standard to wear protective clothing because of the possibility of contamination with toxic materials, change rooms equipped with storage facilities for street clothes and separate storage facilities for the protective clothing shall be provided. 3(f)(10) Clothes Drying Facilities Where working clothes are provided by the employer and become wet or are washed between shifts, provision shall be made to ensure that such clothing is dry before reuse. 3(f)(11) Consumption of Food and Beverages No employee shall be allowed to consume food or beverages in a toilet room, nor in any area exposed to a toxic material. 3(f)(12) Waste Disposal Containers Receptacles constructed of smooth, corrosion resistant, easily cleanable, or disposable materials, shall be provided and used for the disposal of waste food. The number, size, and location of such receptacles shall encourage their use and not result in overfilling. They shall be emptied not less frequently than once each working day, unless unused, and shall be maintained in a clean and sanitary condition. Receptacles shall be provided with a solid tight-fitting cover unless sanitary conditions can be maintained without use of a cover. 3(f)(13) Sanitary Storage No food or beverages shall be stored in toilet rooms or in an area exposed to a toxic material.

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3(f)(14) Food Handling All employee food service facilities and operations shall be carried out in accordance with sound hygienic principles. In all places of employment where all or part of the food service is provided, the food dispensed shall be wholesome, free from spoilage, and shall be processed, prepared, handled, and stored in such a manner as to be protected against contamination. 3(g) Safety Color Code for Marking Physical Hazards The color Red shall be the basic color for the identification of fire protection equipment and apparatus. Safety cans or other portable containers of flammable liquids having a flash point at or below 80 degrees Fahrenheit, table containers of flammable liquids (open cup tester), excluding shipping containers, shall be painted red with some additional clearly visible identification either in the form of a yellow band around the can or the name of the contents conspicuously stenciled or painted on the can in yellow. Red lights shall be provided at barricades and at temporary obstructions, as specified in ANSI Safety Code for Building Construction, A10.2-1944, which is incorporated by reference as specified in Sec. 1910.6. Danger signs shall be painted red. Emergency stop bars on hazardous machines such as rubber mills, wire blocks, flat work ironers, etc., shall be red. Stop buttons or electrical switches which letters or other markings appear, used for emergency stopping of machinery shall be red. Yellow shall be the basic color for designating caution and for marking physical hazards such as: Striking against, stumbling, falling, tripping, and "caught in between." 3(h) Specifications for Accident Prevention Signs and Tags 3(h)(1) General These specifications apply to the design, application, and use of signs or symbols intended to indicate and, in so far as possible, to define specific hazards of a nature such that failure to designate them may lead to accidental injury to workers or the public, or both, or to property damage. These specifications are intended to cover all safety signs except those designed for streets, highways, railroads, and marine regulations. These specifications do not apply to plant bulletin boards or to safety posters. All new signs and replacements of old signs shall be in accordance with these specifications. As used in this section, the word "sign" refers to a surface prepared for the warning of, or safety instructions of, industrial workers or members of the public who may be exposed to hazards. Excluded from this definition, however, are news releases, displays commonly known as safety posters, and bulletins used for employee education. 3(h)(2) Classification of Signs Classification of signs according to use:

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Danger signs - There shall be no variation in the type of design of signs posted to warn of specific dangers and radiation hazards. All employees shall be instructed that danger signs indicate immediate danger and that special precautions are necessary. Caution signs - Caution signs shall be used only to warn against potential hazards or to caution against unsafe practices. All employees shall be instructed that caution signs indicate a possible hazard against which proper precaution should be taken. Safety instruction signs - Safety instruction signs shall be used where there is a need for general instructions and suggestions relative to safety measures. 3(h)(3) Sign Design All signs shall be furnished with rounded or blunt corners and shall be free from sharp edges, burrs, splinters, or other sharp projections. The ends or heads of bolts or other fastening devices shall be located in such a way that they do not constitute a hazard. 3(h)(3)(i) Danger Signs The colors red, black, and white shall be those of opaque glossy samples as specified in Table 1 of Fundamental Specification of Safety Colors for CIE Standard Source "C", American National Standard Z53.1-1967, which is incorporated by reference as specified in Sec. 1910.6. 3(h)(3)(ii) Caution Signs Standard color of the background shall be yellow; and the panel, black with yellow letters. Any letters used against the yellow background shall be black. The colors shall be those of opaque glossy samples as specified in Table 1 of American National Standard Z53.1-1967. Safety instruction signs - Standard color of the background shall be white; and the panel, green with white letters. Any letters used against the white background shall be black. The colors shall be those of opaque glossy samples as specified in Table 1 of American National Standard, Z53.1-1967. 3(h)(3)(iii) Sign Wordings The wording of any sign should be easily read and concise. The sign should contain sufficient information to be easily understood. The wording should make a positive, rather than negative suggestion and should be accurate in fact. 3(h)(4) Biological Hazard Signs The biological hazard warning shall be used to signify the actual or potential presence of a biohazard and to identify equipment, containers, rooms, materials, experimental animals, or combinations thereof, which contain, or are contaminated with, viable hazardous agents. For the III-26

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purpose of this subparagraph the term "biological hazard," or "biohazard," shall include only those infectious agents presenting a risk or potential risk to the well-being of man. 3(h)(5) Accident Prevention Tags This paragraph applies to all accident prevention tags used to identify hazardous conditions and provide a message to employees with respect to hazardous conditions. The following definitions are used: • •

• • •

"Biological hazard" or "BIOHAZARD" mean those infectious agents presenting a risk of death, injury or illness to employees. "Major message" means that a portion of a tag's inscription that is more specific than the signal word and that indicates the specific hazardous condition or the instruction to be communicated to the employee. Examples include: "High Voltage," "Close Clearance," "Do Not Start," or "Do Not Use" or a corresponding pictograph used with a written text or alone. "Pictograph" means a pictorial representation used to identify a hazardous condition or to convey a safety instruction. "Signal word" means that portion of a tag's inscription that contains the word or words that are intended to capture the employee's immediate attention. "Tag" means a device usually made of card, paper, pasteboard, plastic or other material used to identify a hazardous condition.

Tags shall be used as a means to prevent accidental injury or illness to employees who are exposed to hazardous or potentially hazardous conditions, equipment or operations which are out of the ordinary, unexpected or not readily apparent. Tags shall be used until such time as the identified hazard is eliminated or the hazardous operation is completed. Tags need not be used where signs, guarding or other positive means of protection are being used. All required tags shall meet the following criteria: • •

Tags shall contain a signal word and a major message. The signal word shall be either "Danger," "Caution," or "Biological Hazard," "BIOHAZARD," or the biological hazard symbol.

The major message shall indicate the specific hazardous condition or the instruction to be communicated to the employee. The signal word shall be readable at a minimum distance of 1.52 m or such greater distance as warranted by the hazard. The tag's major message shall be presented in either pictographs, written text or both. The signal word and the major message shall be understandable to all employees who may be exposed to the identified hazard.

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All employees shall be informed as to the meaning of the various tags used throughout the workplace and what special precautions are necessary. Tags shall be affixed as close as safely possible to their respective hazards by a positive means such as string, wire, or adhesive that prevents their loss or unintentional removal. Danger tags shall be used in major hazard situations where an immediate hazard presents a threat of death or serious injury to employees. Danger tags shall be used only in these situations. Caution tags shall be used in minor hazard situations where a non-immediate or potential hazard or unsafe practice presents a lesser threat of employee injury. Caution tags shall be used only in these situations. Warning tags may be used to represent a hazard level between "Caution" and "Danger," instead of the required "Caution" tag, provided that they have a signal word of "Warning," an appropriate major message, and otherwise meet the general tag criteria of paragraph (f)(4) of this section. Biological hazard tags shall be used to identify the actual or potential presence of a biological hazard and to identify equipment, containers, rooms, experimental animals, or combinations thereof, that contain or are contaminated with hazardous biological agents. 3(i) Permits for Confined Spaces 3(i)(1) Definitions This section contains additional information and requirements for practices and procedures to protect employees from the hazards of entry into permit-required confined spaces. The following are definitions derived from the U.S. OSHA standards to help orient workers and employees. Acceptable entry conditions means the conditions that must exist in a permit space to allow entry and to ensure that employees involved with a permit-required confined space entry can safely enter into and work within the space. Attendant means an individual stationed outside one or more permit spaces who monitors the authorized entrants and who performs all attendant's duties assigned in the employer's permit space program. Authorized entrant means an employee who is authorized by the employer to enter a permit space. Blanking or blinding means the absolute closure of a pipe, line, or duct by the fastening of a solid plate (such as a spectacle blind or a skillet blind) that completely covers the bore and that is capable of withstanding the maximum pressure of the pipe, line, or duct with no leakage beyond the plate. Confined space means a space that:

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1. Is large enough and so configured that an employee can bodily enter and perform assigned work; and 2. Has limited or restricted means for entry or exit (for example, tanks, vessels, silos, storage bins, hoppers, vaults, and pits are spaces that may have limited means of entry.); and 3. Is not designed for continuous employee occupancy. Double block and bleed means the closure of a line, duct, or pipe by closing and locking or tagging two in-line valves and by opening and locking or tagging a drain or vent valve in the line between the two closed valves. Emergency means any occurrence (including any failure of hazard control or monitoring equipment) or event internal or external to the permit space that could endanger entrants. Engulfment means the surrounding and effective capture of a person by a liquid or finely divided (flowable) solid substance that can be aspirated to cause death by filling or plugging the respiratory system or that can exert enough force on the body to cause death by strangulation, constriction, or crushing. Entry means the action by which a person passes through an opening into a permit-required confined space. Entry includes ensuing work activities in that space and is considered to have occurred as soon as any part of the entrant's body breaks the plane of an opening into the space. Entry permit (permit) means the written or printed document that is provided by the employer to allow and control entry into a permit space and that contains information specified in this section. Entry supervisor means the person (such as the employer, foreman, or crew chief) responsible for determining if acceptable entry conditions are present at a permit space where entry is planned, for authorizing entry and overseeing entry operations, and for terminating entry as required by this section. An entry supervisor also may serve as an attendant or as an authorized entrant, as long as that person is trained and equipped as required by this section for each role he or she fills. Also, the duties of entry supervisor may be passed from one individual to another during the course of an entry operation. Hazardous atmosphere means an atmosphere that may expose employees to the risk of death, incapacitation, and impairment of ability to self-rescue (that is, escape unaided from a permit space), injury, or acute illness from one or more of the following causes: 1. Flammable gas, vapor, or mist in excess of 10 percent of its lower flammable limit (LFL). 2. Airborne combustible dust at a concentration that meets or exceeds its LFL; this concentration may be approximated as a condition in which the dust obscures vision at a distance of 1.52 m or less. 3. Atmospheric oxygen concentration below 19.5 percent or above 23.5 percent; 4. Atmospheric concentration of any substance for which a dose or a permissible exposure limit which could result in employee exposure in excess of safe levels of exposure. For

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exposure limits see Part II (e). An atmospheric concentration of any substance that is not capable of causing death, incapacitation, and impairment of ability to self-rescue, injury, or acute illness due to its health effects is not covered by this provision. 5. Any other atmospheric condition that is immediately dangerous to life or health. For air contaminants which do not have established doses or permissible exposure limits, other sources of information, such as Material Safety Data Sheets, published information, and internal documents can provide guidance in establishing acceptable atmospheric conditions. Hot work permit means the employer's written authorization to perform operations (for example, riveting, welding, cutting, burning, and heating) capable of providing a source of ignition. Immediately dangerous to life or health (IDLH) means any condition that poses an immediate or delayed threat to life or that would cause irreversible adverse health effects or that would interfere with an individual's ability to escape unaided from a permit space. Some materials -hydrogen fluoride gas and cadmium vapor, for example -- may produce immediate transient effects that, even if severe, may pass without medical attention, but are followed by sudden, possibly fatal collapse 12-72 hours after exposure. The victim "feels normal" from recovery from transient effects until collapse. Such materials in hazardous quantities are considered to be "immediately" dangerous to life or health. Inerting means the displacement of the atmosphere in a permit space by a noncombustible gas (such as nitrogen) to such an extent that the resulting atmosphere is noncombustible. It is important to note that inerting produces an IDLH oxygen-deficient atmosphere. Isolation means the process by which a permit space is removed from service and completely protected against the release of energy and material into the space by such means as: blanking or blinding; misaligning or removing sections of lines, pipes, or ducts; a double block and bleed system; lockout or tagout of all sources of energy; or blocking or disconnecting all mechanical linkages. Line breaking means the intentional opening of a pipe, line, or duct that is or has been carrying flammable, corrosive, or toxic material, an inert gas, or any fluid at a volume, pressure, or temperature capable of causing injury. Non-permit confined space means a confined space that does not contain or, with respect to atmospheric hazards, have the potential to contain any hazard capable of causing death or serious physical harm. Oxygen deficient atmosphere means an atmosphere containing less than 19.5 percent oxygen by volume. Oxygen enriched atmosphere means an atmosphere containing more than 23.5 percent oxygen by volume.

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Permit-required confined space (permit space) means a confined space that has one or more of the following characteristics: 1. Contains or has a potential to contain a hazardous atmosphere; 2. Contains a material that has the potential for engulfing an entrant; 3. Has an internal configuration such that an entrant could be trapped or asphyxiated by inwardly converging walls or by a floor which slopes downward and tapers to a smaller cross-section; or 4. Contains any other recognized serious safety or health hazard. Permit-required confined space program (permit space program) means the employer's overall program for controlling, and, where appropriate, for protecting employees from, permit space hazards and for regulating employee entry into permit spaces. Permit system means the employer's written procedure for preparing and issuing permits for entry and for returning the permit space to service following termination of entry. Prohibited condition means any condition in a permit space that is not allowed by the permit during the period when entry is authorized. Rescue service means the personnel designated to rescue employees from permit spaces. Retrieval system means the equipment (including a retrieval line, chest or full-body harness, wristlets, if appropriate, and a lifting device or anchor) used for non-entry rescue of persons from permit spaces. Testing means the process by which the hazards that may confront entrants of a permit space are identified and evaluated. Testing includes specifying the tests that are to be performed in the permit space. Testing enables employers both to devise and implement adequate control measures for the protection of authorized entrants and to determine if acceptable entry conditions are present immediately prior to, and during, entry. 3(i)(2) General Comments and Requirements The employer shall evaluate the workplace to determine if any spaces are permit-required confined spaces. If the workplace contains permit spaces, the employer shall inform exposed employees, by posting danger signs or by any other equally effective means, of the existence and location of and the danger posed by the permit spaces. A sign reading DANGER – PERMIT-REQUIRED CONFINED SPACE, DO NOT ENTER or using other similar language would satisfy the requirement for a sign. If the employer decides that its employees will not enter permit spaces, the employer shall take effective measures to prevent its employees from entering the permit spaces.

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If the employer decides that its employees will enter permit spaces, the employer shall develop and implement a written permit space program that complies with this section. The written program shall be available for inspection by employees and their authorized representatives. An employer whose employees enter a permit space need not comply with the recommendations of this section provided that: • • • • •

The employer can demonstrate that the only hazard posed by the permit space is an actual or potential hazardous atmosphere; The employer can demonstrate that continuous forced air ventilation alone is sufficient to maintain that permit space safe for entry; The employer develops monitoring and inspection data that supports the demonstrations required in this section; The determinations and supporting data required are documented by the employer and are made available to each employee who enters the permit space; and Entry into the permit space is performed in accordance with the requirements of this section.

The following requirements apply to entry into permit spaces that meet the conditions set forth in this section. • •

•

Any conditions making it unsafe to remove an entrance cover shall be eliminated before the cover is removed. When entrance covers are removed, the opening shall be promptly guarded by a railing, temporary cover, or other temporary barrier that will prevent an accidental fall through the opening and that will protect each employee working in the space from foreign objects entering the space. Before an employee enters the space, the internal atmosphere shall be tested, with a calibrated direct-reading instrument, for oxygen content, for flammable gases and vapors, and for potential toxic air contaminants, in that order. Any employee who enters the space, or that employee's authorized representative, shall be provided an opportunity to observe the pre-entry testing required by this paragraph.

3(i)(3) Oxygen Content, Flammable Gases and Vapors, and Potential Toxic Air Contaminants There may be no hazardous atmosphere within the space whenever any employee is inside the space. Continuous forced air ventilation shall be used, as follows: • •

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An employee may not enter the space until the forced air ventilation has eliminated any hazardous atmosphere. The forced air ventilation shall be so directed as to ventilate the immediate areas where an employee is or will be present within the space and shall continue until all employees have left the space.

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The air supply for the forced air ventilation shall be from a clean source and may not increase the hazards in the space. The atmosphere within the space shall be periodically tested as necessary to ensure that the continuous forced air ventilation is preventing the accumulation of a hazardous atmosphere. Any employee who enters the space, or that employee's authorized representative, shall be provided with an opportunity to observe the periodic testing required by this paragraph. If a hazardous atmosphere is detected during entry. Each employee shall leave the space immediately. The space shall be evaluated to determine how the hazardous atmosphere developed; and Measures shall be implemented to protect employees from the hazardous atmosphere before any subsequent entry takes place.

The employer shall verify that the space is safe for entry and that the pre-entry measures required of this section have been taken, through a written certification that contains the date, the location of the space, and the signature of the person providing the certification. The certification shall be made before entry and shall be made available to each employee entering the space or to that employee's authorized representative. When there are changes in the use or configuration of a non-permit confined space that might increase the hazards to entrants, the employer shall reevaluate that space and, if necessary, reclassify it as a permit-required confined space. A space classified by the employer as a permit-required confined space may be reclassified as a non-permit confined space under the following procedures: •

•

If the permit space poses no actual or potential atmospheric hazards and if all hazards within the space are eliminated without entry into the space, the permit space may be reclassified as a non-permit confined space for as long as the non-atmospheric hazards remain eliminated. If it is necessary to enter the permit space to eliminate hazards, such entry shall be performed under the recommendations of this section. If testing and inspection during that entry demonstrate that the hazards within the permit space have been eliminated, the permit space may be reclassified as a non-permit confined space for as long as the hazards remain eliminated. Control of atmospheric hazards through forced air ventilation does not constitute elimination of the hazards.

The employer shall document the basis for determining that all hazards in a permit space have been eliminated, through a certification that contains the date, the location of the space, and the signature of the person making the determination. The certification shall be made available to each employee entering the space or to that employee's authorized representative. If hazards arise within a permit space that has been declassified to a non-permit space, each employee in the space shall exit the space. The employer shall then reevaluate the space and determine whether it must be reclassified as a permit space, in accordance with other applicable provisions of this section. III-33

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When an employer (host employer) arranges to have employees of another employer (contractor) perform work that involves permit space entry, the host employer shall: • • • • •

Inform the contractor that the workplace contains permit spaces and that permit space entry is allowed only through compliance with a permit space program meeting the requirements of this section; Apprise the contractor of the elements, including the hazards identified and the host employer's experience with the space, that make the space in question a permit space; Apprise the contractor of any precautions or procedures that the host employer has implemented for the protection of employees in or near permit spaces where contractor personnel will be working; Coordinate entry operations with the contractor, when both host employer personnel and contractor personnel will be working in or near permit spaces; and Debrief the contractor at the conclusion of the entry operations regarding the permit space program followed and regarding any hazards confronted or created in permit spaces during entry operations.

In addition to complying with the permit space requirements that apply to all employers, each contractor who is retained to perform permit space entry operations shall: • • •

Obtain any available information regarding permit space hazards and entry operations from the host employer; Coordinate entry operations with the host employer, when both host employer personnel and contractor personnel will be working in or near permit spaces; and Inform the host employer of the permit space program that the contractor will follow and of any hazards confronted or created in permit spaces, either through a debriefing or during the entry operation.

3(i)(4) Permit Space Program 3(i)(4)(i) General Details The employer shall: • • •

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Implement the measures necessary to prevent unauthorized entry; Identify and evaluate the hazards of permit spaces before employees enter them; Develop and implement the means, procedures, and practices necessary for safe permit space entry operations, including, but not limited to, the following: – Specifying acceptable entry conditions providing each authorized entrant or that employee's authorized representative with the opportunity to observe any monitoring or testing of permit spaces; – Isolate the permit space; – Perform the following: Purging, inerting, flushing, or ventilating the permit space as necessary to eliminate or control atmospheric hazards; – Provide pedestrian, vehicle, or other barriers as necessary to protect entrants from external hazards; and

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Verify that conditions in the permit space are acceptable for entry throughout the duration of an authorized entry.

The employer shall provide the following equipment at no cost to employees, maintain that equipment properly, and ensure that employees use that equipment properly: • • • • • • • • •

Testing and monitoring equipment needed to comply with this section; Ventilating equipment needed to obtain acceptable entry conditions; Communications equipment necessary for compliance with this section; Personal protective equipment insofar as feasible engineering and work practice controls do not adequately protect employees; Lighting equipment needed to enable employees to see well enough to work safely and to exit the space quickly in an emergency; Barriers and shields as required by this section; Equipment, such as ladders, needed for safe ingress and egress by authorized entrants; Rescue and emergency equipment needed to comply with this section, except to the extent that the equipment is provided by rescue services; and Any other equipment necessary for safe entry into and rescue from permit spaces.

The employer shall evaluate permit space conditions as follows when entry operations are conducted: •

• •

Test conditions in the permit space to determine if acceptable entry conditions exist before entry is authorized to begin, except that, if isolation of the space is infeasible because the space is large or is part of a continuous system (such as a sewer), pre-entry testing shall be performed to the extent feasible before entry is authorized and, if entry is authorized, entry conditions shall be continuously monitored in the areas where authorized entrants are working; Test or monitor the permit space as necessary to determine if acceptable entry conditions are being maintained during the course of entry operations; and When testing for atmospheric hazards, test first for oxygen, then for combustible gases and vapors, and then for toxic gases and vapors.

The employer shall provide each authorized entrant or that employee's authorized representative an opportunity to observe the pre-entry and any subsequent testing or monitoring of permit spaces. The employer shall reevaluate the permit space in the presence of any authorized entrant or that employee's authorized representative who requests that the employer conduct such reevaluation because the entrant or representative has reason to believe that the evaluation of that space may not have been adequate. The employer shall immediately provide each authorized entrant or that employee's authorized representative with the results of any testing conducted.

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3(i)(4)(ii) Attendant The employer shall provide at least one attendant outside the permit space into which entry is authorized for the duration of entry operations. Attendants may be assigned to monitor more than one permit space provided the duties of this section can be effectively performed for each permit space that is monitored. Likewise, attendants may be stationed at any location outside the permit space to be monitored as long as the duties described in this section can be effectively performed for each permit space that is monitored. If multiple spaces are to be monitored by a single attendant, include in the permit program the means and procedures to enable the attendant to respond to an emergency affecting one or more of the permit spaces being monitored without distraction from the attendant's responsibilities. Designate the persons who are to have active roles (as, for example, authorized entrants, attendants, entry supervisors, or persons who test or monitor the atmosphere in a permit space) in entry operations, identify the duties of each such employee, and provide each such employee with the training required. Employers should develop and implement procedures for summoning rescue and emergency services, for rescuing entrants from permit spaces, for providing necessary emergency services to rescued employees, and for preventing unauthorized personnel from attempting a rescue. Employers should develop and implement a system for the preparation, issuance, use, and cancellation of entry permits as required by this section. Employers should develop and implement procedures to coordinate entry operations when employees of more than one employer are working simultaneously as authorized entrants in a permit space, so that employees of one employer do not endanger the employees of any other employer. Employers should develop and implement procedures (such as closing off a permit space and canceling the permit) necessary for concluding the entry after entry operations have been completed. Employers should review entry operations when the employer has reason to believe that the measures taken under the permit space program may not protect employees and revise the program to correct deficiencies found to exist before subsequent entries are authorized. Examples of circumstances requiring the review of the permit space program are: any unauthorized entry of a permit space, the detection of a permit space hazard not covered by the permit, the detection of a condition prohibited by the permit, the occurrence of an injury or nearmiss during entry, a change in the use or configuration of a permit space, and employee complaints about the effectiveness of the program. Employers should review the permit space program, using the canceled permits retained within 1 year after each entry and revise the program as necessary, to ensure that employees participating in entry operations are protected from permit space hazards. Employers may perform a single

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annual review covering all entries performed during a 12-month period. If no entry is performed during a 12-month period, no review is necessary. 3(i)(4)(iii) The Permit System Before entry is authorized, the employer shall document the completion of measures required by this section by preparing an entry permit. Before entry begins, the entry supervisor identified on the permit shall sign the entry permit to authorize entry. The completed permit shall be made available at the time of entry to all authorized entrants or their authorized representatives, by posting it at the entry portal or by any other equally effective means, so that the entrants can confirm that pre-entry preparations have been completed. The duration of the permit may not exceed the time required to complete the assigned task or job identified on the permit. The entry supervisor shall terminate entry and cancel the entry permit when: • •

The entry operations covered by the entry permit have been completed; or A condition that is not allowed under the entry permit arises in or near the permit space.

The employer shall retain each canceled entry permit for at least 1 year to facilitate the review of the permit-required confined space program required of this section. Any problems encountered during an entry operation shall be noted on the pertinent permit so that appropriate revisions to the permit space program can be made. 3(i)(4)(iv) Entry Permit The entry permit that documents compliance with this section and authorizes entry to a permit space shall identify: • • • •

• • •

The permit space to be entered. The purpose of the entry. The date and the authorized duration of the entry permit. The authorized entrants within the permit space, by name or by such other means (for example, through the use of rosters or tracking systems) as will enable the attendant to determine quickly and accurately, for the duration of the permit, which authorized entrants are inside the permit space. This requirement may be met by inserting a reference on the entry permit as to the means used, such as a roster or tracking system, to keep track of the authorized entrants within the permit space. The personnel, by name, currently serving as attendants. The individual, by name, currently serving as entry supervisor, with a space for the signature or initials of the entry supervisor who originally authorized entry. The hazards of the permit space to be entered.

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The measures used to isolate the permit space and to eliminate or control permit space hazards before entry. Those measures can include the lockout or tagging of equipment and procedures for purging, inerting, ventilating, and flushing permit spaces. The acceptable entry conditions. The results of initial and periodic tests performed, accompanied by the names or initials of the testers and by an indication of when the tests were performed. The rescue and emergency services that can be summoned and the means (such as the equipment to use and the numbers to call) for summoning those services; The communication procedures used by authorized entrants and attendants to maintain contact during the entry. Equipment, such as personal protective equipment, testing equipment, communications equipment, alarm systems, and rescue equipment, to be provided for compliance with this section. Any other information whose inclusion is necessary, given the circumstances of the particular confined space, in order to ensure employee safety; and any additional permits, such as for hot work, that have been issued to authorize work in the permit space.

3(i)(4)(v) Training The employer shall provide training so that all employees whose work is regulated acquire the understanding, knowledge, and skills necessary for the safe performance of the duties. Training shall be provided to each affected employee: • • • •

Before the employee is first assigned duties under this section; Before there is a change in assigned duties; Whenever there is a change in permit space operations that presents a hazard about which an employee has not previously been trained; and Whenever the employer has reason to believe either that there are deviations from the permit space entry procedures or that there are inadequacies in the employee's knowledge or use of these procedures.

The training shall be designed to establish employee proficiency in the duties required by this section and shall introduce new or revised procedures, as necessary, for compliance with this section. The employer shall certify the training. The certification shall contain each employee's name, the signatures or initials of the trainers, and the dates of training. The certification shall be available for inspection by employees and their authorized representatives. 3(i)(4)(vi) Duties of Authorized Entrants The employer shall ensure that all authorized entrants: • • III-38

Know the hazards that may be faced during entry, including information on the mode, signs or symptoms, and consequences of the exposure; Properly use equipment;

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Communicate with the attendant as necessary to enable the attendant to monitor entrant status and to enable the attendant to alert entrants of the need to evacuate the space; Alert the attendant whenever: – The entrant recognizes any warning sign or symptom of exposure to a dangerous situation, or – The entrant detects a prohibited condition; and – Exit from the permit space as quickly as possible whenever:  An order to evacuate is given by the attendant or the entry supervisor,  The entrant recognizes any warning sign or symptom of exposure to a dangerous situation,  The entrant detects a prohibited condition, or  An evacuation alarm is activated.

3(i)(4)(vii) Duties of Attendants The employer shall ensure that each attendant: • • • •

• •

• •

Knows the hazards that may be faced during entry, including information on the mode, signs or symptoms, and consequences of the exposure; Is aware of possible behavioral effects of hazard exposure in authorized entrants; Continuously maintains an accurate count of authorized entrants in the permit space and ensures that the means used to identify authorized entrants under paragraph (f)(4) of this section accurately identifies who is in the permit space; Remains outside the permit space during entry operations until relieved by another attendant. When the employer's permit entry program allows attendant entry for rescue, attendants may enter a permit space to attempt a rescue if they have been trained and equipped for rescue operations; Communicates with authorized entrants as necessary to monitor entrant status and to alert entrants of the need to evacuate the space; Monitors activities inside and outside the space to determine if it is safe for entrants to remain in the space and orders the authorized entrants to evacuate the permit space immediately under any of the following conditions: – If the attendant detects a prohibited condition; – If the attendant detects the behavioral effects of hazard exposure in an authorized entrant; – If the attendant detects a situation outside the space that could endanger the authorized entrants; or – If the attendant cannot effectively and safely perform all the duties required of this section; Summon rescue and other emergency services as soon as the attendant determines that authorized entrants may need assistance to escape from permit space hazards; Takes the following actions when unauthorized persons approach or enter a permit space while entry is underway: – Warn the unauthorized persons that they must stay away from the permit space; – Advise the unauthorized persons that they must exit immediately if they have entered the permit space; and

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Inform the authorized entrants and the entry supervisor if unauthorized persons have entered the permit space; Performs non-entry rescues as specified by the employer's rescue procedure; and Performs no duties that might interfere with the attendant's primary duty to monitor and protect the authorized entrants.

3(i)(4)(viii) Duties of Entry Supervisors The employer shall ensure that each entry supervisor: • •

• • • •

Knows the hazards that may be faced during entry, including information on the mode, signs or symptoms, and consequences of the exposure; Verifies, by checking that the appropriate entries have been made on the permit, that all tests specified by the permit have been conducted and that all procedures and equipment specified by the permit are in place before endorsing the permit and allowing entry to begin; Terminates the entry and cancels the permit; Verifies that rescue services are available and that the means for summoning them are operable; Removes unauthorized individuals who enter or who attempt to enter the permit space during entry operations; and Determines, whenever responsibility for a permit space entry operation is transferred and at intervals dictated by the hazards and operations performed within the space that entry operations remain consistent with terms of the entry permit and that acceptable entry conditions are maintained.

3(i)(4)(ix) Rescue and Emergency Services An employer who designates rescue and emergency services shall: • • •

• •

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Evaluate a prospective rescuer's ability to respond to a rescue summons in a timely manner, considering the hazard(s) identified; what will be considered timely will vary according to the specific hazards involved in each entry. Evaluate a prospective rescue service's ability, in terms of proficiency with rescue-related tasks and equipment, to function appropriately while rescuing entrants from the particular permit space or types of permit spaces identified; Select a rescue team or service from those evaluated that: – Has the capability to reach the victim(s) within a time frame that is appropriate for the permit space hazard(s) identified; – Is equipped for and proficient in performing the needed rescue services; Inform each rescue team or service of the hazards they may confront when called on to perform rescue at the site; and Provide the rescue team or service selected with access to all permit spaces from which rescue may be necessary so that the rescue service can develop appropriate rescue plans and practice rescue operations.

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An employer whose employees have been designated to provide permit space rescue and emergency services shall take the following measures: • • • •

Provide affected employees with the personal protective equipment (PPE) needed to conduct permit space rescues safely and train affected employees so they are proficient in the use of that PPE, at no cost to those employees; Train affected employees to perform assigned rescue duties. The employer must ensure that such employees successfully complete the training required to establish proficiency as an authorized entrant; Train affected employees in basic first-aid and cardiopulmonary resuscitation (CPR). The employer shall ensure that at least one member of the rescue team or service holding a current certification in first aid and CPR is available; and Ensure that affected employees practice making permit space rescues at least once every 12 months, by means of simulated rescue operations in which they remove dummies, manikins, or actual persons from the actual permit spaces or from representative permit spaces. Representative permit spaces shall, with respect to opening size, configuration, and accessibility, simulate the types of permit spaces from which a rescue is to be performed.

To facilitate non-entry rescue, retrieval systems or methods shall be used whenever an authorized entrant enters a permit space, unless the retrieval equipment would increase the overall risk of entry or would not contribute to the rescue of the entrant. Retrieval systems shall meet the following requirements. •

•

Each authorized entrant shall use a chest or full body harness, with a retrieval line attached at the center of the entrant's back near shoulder level, above the entrant's head, or at another point which the employer can establish presents a profile small enough for the successful removal of the entrant. Wristlets may be used in lieu of the chest or full body harness if the employer can demonstrate that the use of a chest or full body harness is infeasible or creates a greater hazard and that the use of wristlets is the safest and most effective alternative. The other end of the retrieval line shall be attached to a mechanical device or fixed point outside the permit space in such a manner that rescue can begin as soon as the rescuer becomes aware that rescue is necessary. A mechanical device shall be available to retrieve personnel from vertical type permit spaces more than 1.52 m deep.

If an injured entrant is exposed to a substance for which a Material Safety Data Sheet (MSDS) or other similar written information is required to be kept at the worksite, that MSDS or written information shall be made available to the medical facility treating the exposed entrant. 3(i)(4)(x) Employee Participation Employers shall consult with affected employees and their authorized representatives on the development and implementation of all aspects of the permit space program. Employers shall make available to affected employees and their authorized representatives all information required to be developed by this section. III-41

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3(i)(4)(xi)Procedures for Atmospheric Testing 3(i)(4)(xi)(i) Purpose Atmospheric testing is required for several purposes: 1. Evaluation testing. The atmosphere of a confined space should be analyzed using equipment of sufficient sensitivity and specificity to identify and evaluate any hazardous atmospheres that may exist or arise, so that appropriate permit entry procedures can be developed and acceptable entry conditions stipulated for that space. Evaluation and interpretation of these data, and development of the entry procedure, should be done by, or reviewed by, a technically qualified professional (e.g., a NERC recognized consultation service, or certified industrial hygienist, registered safety engineer, certified safety professional, certified marine chemist, etc.) based on evaluation of all serious hazards. 2. Verification testing. The atmosphere of a permit space which may contain a hazardous atmosphere should be tested for residues of all contaminants identified by evaluation testing using permit specified equipment to determine that residual concentrations at the time of testing and entry are within the range of acceptable entry conditions. Results of testing (i.e., actual concentration, etc.) should be recorded on the permit in the space provided adjacent to the stipulated acceptable entry condition. 3(i)(4)(xi)(ii)Duration of Testing Measurement of values for each atmospheric parameter should be made for at least the minimum response time of the test instrument specified by the manufacturer. 3(i)(4)(xi)(iii) Testing Stratified Atmospheres When monitoring for entries involving a descent into atmospheres that may be stratified, the atmospheric envelope should be tested at a distance of approximately 1.22 m in the direction of travel and to each side. If a sampling probe is used, the entrant's rate of progress should be slowed to accommodate the sampling speed and detector response. 3(i)(4)(xi)(iv) Order of Testing A test for oxygen is performed first because most combustible gas meters are oxygen dependent and will not provide reliable readings in an oxygen deficient atmosphere. Combustible gases are tested for next because the threat of fire or explosion is both more immediate and more life threatening, in most cases, than exposure to toxic gases and vapors. If tests for toxic gases and vapors are necessary, they are performed last. 3(j) Control of Hazardous Energy (Lockout/Tagout) 3(j)(1) General Information This standard covers the servicing and maintenance of machines and equipment in which the unexpected energization or start up of the machines or equipment, or release of stored energy could cause injury to employees. This standard establishes minimum performance requirements for the control of such hazardous energy.

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This standard applies to the control of energy during servicing and/or maintenance of machines and equipment when: • •

An employee is required to remove or bypass a guard or other safety device; or An employee is required to place any part of his or her body into an area on a machine or piece of equipment where work is actually performed upon the material being processed (point of operation) or where an associated danger zone exists during a machine operating cycle.

Note that minor tool changes and adjustments, and other minor servicing activities, which take place during normal production operations, are not covered by this standard if they are routine, repetitive, and integral to the use of the equipment for production, provided that the work is performed using alternative measures which provide effective protection. This section requires employers to establish a program and utilize procedures for affixing appropriate lockout devices or tagout devices to energy isolating devices, and to otherwise disable machines or equipment to prevent unexpected energization, start up or release of stored energy in order to prevent injury to employees. When other standards in this part require the use of lockout or tagout, they shall be used and supplemented by the procedural and training requirements of this section. 3(j)(2) Definitions Affected employee. An employee whose job requires him/her to operate or use a machine or equipment on which servicing or maintenance is being performed under lockout or tagout, or whose job requires him/her to work in an area in which such servicing or maintenance is being performed. Authorized employee. A person who locks out or tags out machines or equipment in order to perform servicing or maintenance on that machine or equipment. An affected employee becomes an authorized employee when that employee's duties include performing servicing or maintenance covered under this section. Capable of being locked out. An energy isolating device is capable of being locked out if it has a hasp or other means of attachment to which, or through which, a lock can be affixed, or it has a locking mechanism built into it. Other energy isolating devices are capable of being locked out, if lockout can be achieved without the need to dismantle, rebuild, or replace the energy isolating device or permanently alter its energy control capability. Energized. Connected to an energy source or containing residual or stored energy. Energy isolating device. A mechanical device that physically prevents the transmission or release of energy, including but not limited to the following: A manually operated electrical circuit breaker; a disconnect switch; a manually operated switch by which the conductors of a circuit can be disconnected from all ungrounded supply conductors, and, in addition, no pole can be operated independently; a line valve; a block; and any similar device used to block or isolate III-43

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energy. Push buttons, selector switches and other control circuit type devices are not energy isolating devices. Energy source. Any source of electrical, mechanical, hydraulic, pneumatic, chemical, thermal, or other energy. Hot tap. A procedure used in the repair, maintenance and services activities which involves welding on a piece of equipment (pipelines, vessels or tanks) under pressure, in order to install connections or appurtenances. it is commonly used to replace or add sections of pipeline without the interruption of service for air, gas, water, steam, and petrochemical distribution systems. Lockout. The placement of a lockout device on an energy isolating device, in accordance with an established procedure, ensuring that the energy isolating device and the equipment being controlled cannot be operated until the lockout device is removed. Lockout device. A device that utilizes a positive means such as a lock, either key or combination type, to hold an energy isolating device in the safe position and prevent the energizing of a machine or equipment. Included are blank flanges and bolted slip blinds. Normal production operations. The utilization of a machine or equipment to perform its intended production function. Servicing and/or maintenance. Workplace activities such as constructing, installing, setting up, adjusting, inspecting, modifying, and maintaining and/or servicing machines or equipment. These activities include lubrication, cleaning or unjamming of machines or equipment and making adjustments or tool changes, where the employee may be exposed to the unexpected energization or startup of the equipment or release of hazardous energy. Setting up. Any work performed to prepare a machine or equipment to perform its normal production operation. Tagout. The placement of a tagout device on an energy isolating device, in accordance with an established procedure, to indicate that the energy isolating device and the equipment being controlled may not be operated until the tagout device is removed. Tagout device. A prominent warning device, such as a tag and a means of attachment, which can be securely fastened to an energy isolating device in accordance with an established procedure, to indicate that the energy isolating device and the equipment being controlled may not be operated until the tagout device is removed. Energy control program. The employer shall establish a program consisting of energy control procedures, employee training and periodic inspections to ensure that before any employee performs any servicing or maintenance on a machine or equipment where the unexpected energizing, startup or release of stored energy could occur and cause injury, the machine or equipment shall be isolated from the energy source and rendered inoperative.

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3(j)(3) Elements of Lockout/Tagout If an energy isolating device is not capable of being locked out, the employer's energy control program under paragraph (c)(1) of this section shall utilize a tagout system. If an energy isolating device is capable of being locked out, the employer's energy control program shall utilize lockout, unless the employer can demonstrate that the utilization of a tagout system will provide full employee protection. 3(j)(4) Full Employee Protection When a tagout device is used on an energy isolating device which is capable of being locked out, the tagout device shall be attached at the same location that the lockout device would have been attached, and the employer shall demonstrate that the tagout program will provide a level of safety equivalent to that obtained by using a lockout program. In demonstrating that a level of safety is achieved in the tagout program which is equivalent to the level of safety obtained by using a lockout program, the employer shall demonstrate full compliance with all tagout-related provisions of this standard together with such additional elements as are necessary to provide the equivalent safety available from the use of a lockout device. Additional means to be considered as part of the demonstration of full employee protection shall include the implementation of additional safety measures such as the removal of an isolating circuit element, blocking of a controlling switch, opening of an extra disconnecting device, or the removal of a valve handle to reduce the likelihood of inadvertent energization. 3(j)(5) Energy Control Procedure Procedures shall be developed, documented and utilized for the control of potentially hazardous energy when employees are engaged in the activities covered by this section. The procedures shall clearly and specifically outline the scope, purpose, authorization, rules, and techniques to be utilized for the control of hazardous energy, and the means to enforce compliance including, but not limited to, the following: • • • •

A specific statement of the intended use of the procedure; Specific procedural steps for shutting down, isolating, blocking and securing machines or equipment to control hazardous energy; Specific procedural steps for the placement, removal and transfer of lockout devices or tagout devices and the responsibility for them; and Specific requirements for testing a machine or equipment to determine and verify the effectiveness of lockout devices, tagout devices, and other energy control measures.

3(j)(6) Protective Materials and Hardware Locks, tags, chains, wedges, key blocks, adapter pins, self-locking fasteners, or other hardware shall be provided by the employer for isolating, securing or blocking of machines or equipment from energy sources.

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Lockout devices and tagout devices shall be singularly identified; shall be the only devices(s) used for controlling energy; shall not be used for other purposes; and shall meet the following requirements: Lockout and tagout devices shall be capable of withstanding the environment to which they are exposed for the maximum period of time that exposure is expected. Tagout devices shall be constructed and printed so that exposure to weather conditions or wet and damp locations will not cause the tag to deteriorate or the message on the tag to become illegible. Tags shall not deteriorate when used in corrosive environments such as areas where acid and alkali chemicals are handled and stored. Lockout and tagout devices shall be standardized within the facility in at least one of the following criteria: color; shape; or size; and additionally, in the case of tagout devices, print and format shall be standardized. Lockout devices shall be substantial enough to prevent removal without the use of excessive force or unusual techniques, such as with the use of bolt cutters or other metal cutting tools. Tagout devices, including their means of attachment, shall be substantial enough to prevent inadvertent or accidental removal. Tagout device attachment means shall be of a non-reusable type, attachable by hand, self-locking, and non-releasable with a minimum unlocking strength of no less than 22.68 kilograms and having the general design and basic characteristics of being at least equivalent to a one-piece, all environment-tolerant nylon cable tie. Lockout devices and tagout devices shall indicate the identity of the employee applying the device(s). Tagout devices shall warn against hazardous conditions if the machine or equipment is energized and shall include a legend such as the following: • • • • •

Do Not Start. Do Not Open. Do Not Close. Do Not Energize. Do Not Operate.

3(j)(7) Inspection The employer shall conduct a periodic inspection of the energy control procedure at least annually to ensure that the procedure and the requirements of this standard are being followed. The periodic inspection shall be performed by an authorized employee other than the ones(s) utilizing the energy control procedure being inspected.

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The periodic inspection shall be conducted to correct any deviations or inadequacies identified. Where lockout is used for energy control, the periodic inspection shall include a review, between the inspector and each authorized employee, of that employee's responsibilities under the energy control procedure being inspected. Where tagout is used for energy control, the periodic inspection shall include a review, between the inspector and each authorized and affected employee, of that employee's responsibilities under the energy control procedure being inspected, and the elements set forth in this section. The employer shall certify that the periodic inspections have been performed. The certification shall identify the machine or equipment on which the energy control procedure was being utilized, the date of the inspection, the employees included in the inspection, and the person performing the inspection. 3(j)(8) Training and Communication The employer shall provide training to ensure that the purpose and function of the energy control program are understood by employees and that the knowledge and skills required for the safe application, usage, and removal of the energy controls are acquired by employees. The training shall include the following: • •

Each authorized employee shall receive training in the recognition of applicable hazardous energy sources, the type and magnitude of the energy available in the workplace, and the methods and means necessary for energy isolation and control. Each affected employee shall be instructed in the purpose and use of the energy control procedure.

All other employees whose work operations are or may be in an area where energy control procedures may be utilized, shall be instructed about the procedure, and about the prohibition relating to attempts to restart or reenergize machines or equipment which are locked out or tagged out. When tagout systems are used, employees shall also be trained in the following limitations of tags: • Tags are essentially warning devices affixed to energy isolating devices, and do not provide the physical restraint on those devices that is provided by a lock. • When a tag is attached to an energy isolating means, it is not to be removed without authorization of the authorized person responsible for it, and it is never to be bypassed, ignored, or otherwise defeated. • Tags must be legible and understandable by all authorized employees, affected employees, and all other employees whose work operations are or may be in the area, in order to be effective. • Tags and their means of attachment must be made of materials which will withstand the environmental conditions encountered in the workplace. • Tags may evoke a false sense of security, and their meaning needs to be understood as part of the overall energy control program.

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Tags must be securely attached to energy isolating devices so that they cannot be inadvertently or accidentally detached during use.

Retraining shall be provided for all authorized and affected employees whenever there is a change in their job assignments, a change in machines, equipment or processes that present a new hazard, or when there is a change in the energy control procedures. Additional retraining shall also be conducted whenever a periodic inspection is needed, or whenever the employer has reason to believe that there are deviations from or inadequacies in the employee's knowledge or use of the energy control procedures. The retraining shall reestablish employee proficiency and introduce new or revised control methods and procedures, as necessary. The employer shall certify that employee training has been accomplished and is being kept up to date. The certification shall contain each employee's name and dates of training. 3(j)(9) Energy Isolation Lockout or tagout shall be performed only by the authorized employees who are performing the servicing or maintenance. Affected employees shall be notified by the employer or authorized employee of the application and removal of lockout devices or tagout devices. Notification shall be given before the controls are applied, and after they are removed from the machine or equipment. The established procedures for the application of energy control (the lockout or tagout procedures) shall cover the following elements and actions and shall be done in the following sequence: • • • • • •

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Before an authorized or affected employee turns off a machine or equipment, the authorized employee shall have knowledge of the type and magnitude of the energy, the hazards of the energy to be controlled, and the method or means to control the energy. The machine or equipment shall be turned off or shut down using the procedures established for the machine or equipment. An orderly shutdown must be utilized to avoid any additional or increased hazard(s) to employees as a result of the equipment stoppage. All energy isolating devices that are needed to control the energy to the machine or equipment shall be physically located and operated in such a manner as to isolate the machine or equipment from the energy source(s). Lockout or tagout devices shall be affixed to each energy isolating device by authorized employees. Lockout devices, where used, shall be affixed in a manner to that will hold the energy isolating devices in a "safe" or "off" position. Tagout devices, where used, shall be affixed in such a manner as will clearly indicate that the operation or movement of energy isolating devices from the "safe" or "off" position is prohibited.

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Where tagout devices are used with energy isolating devices designed with the capability of being locked, the tag attachment shall be fastened at the same point at which the lock would have been attached. Where a tag cannot be affixed directly to the energy isolating device, the tag shall be located as close as safely possible to the device, in a position that will be immediately obvious to anyone attempting to operate the device. Following the application of lockout or tagout devices to energy isolating devices, all potentially hazardous stored or residual energy shall be relieved, disconnected, restrained, and otherwise rendered safe. If there is a possibility of reaccumulation of stored energy to a hazardous level, verification of isolation shall be continued until the servicing or maintenance is completed, or until the possibility of such accumulation no longer exists. Prior to starting work on machines or equipment that have been locked out or tagged out, the authorized employee shall verify that isolation and deenergization of the machine or equipment have been accomplished.

Before lockout or tagout devices are removed and energy is restored to the machine or equipment, procedures shall be followed and actions taken by the authorized employee(s) to ensure the following: • • • •

The work area shall be inspected to ensure that nonessential items have been removed and to ensure that machine or equipment components are operationally intact. The work area shall be checked to ensure that all employees have been safely positioned or removed. After lockout or tagout devices have been removed and before a machine or equipment is started, affected employees shall be notified that the lockout or tagout device(s) have been removed. Each lockout or tagout device shall be removed from each energy isolating device by the employee who applied the device.

3(j)(10) Group Lockout or Tagout When servicing and/or maintenance is performed by a crew, craft, department or other group, they shall utilize a procedure which affords the employees a level of protection equivalent to that provided by the implementation of a personal lockout or tagout device. Group lockout or tagout devices shall be used in accordance with the procedures including, but not necessarily limited to, the following specific requirements: • •

Primary responsibility is vested in an authorized employee for a set number of employees working under the protection of a group lockout or tagout device (such as an operations lock). Provision for the authorized employee to ascertain the exposure status of individual group members with regard to the lockout or tagout of the machine or equipment.

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When more than one crew, craft, department, etc. is involved, assignment of overall jobassociated lockout or tagout control responsibility to an authorized employee designated to coordinate affected work forces and ensure continuity of protection. Each authorized employee shall affix a personal lockout or tagout device to the group lockout device, group lockbox, or comparable mechanism when he or she begins work, and shall remove those devices when he or she stops working on the machine or equipment being serviced or maintained.

Specific procedures shall be utilized during shift or personnel changes to ensure the continuity of lockout or tagout protection, including provision for the orderly transfer of lockout or tagout device protection between off-going and oncoming employees, to minimize exposure to hazards from the unexpected energization or start-up of the machine or equipment, or the release of stored energy. 3(k) Medical Services and First Aid The employer shall ensure the ready availability of medical personnel for advice and consultation on matters of plant health. In the absence of an infirmary, clinic, or hospital in near proximity to the workplace which is used for the treatment of all injured employees, a person or persons shall be adequately trained to render first aid. Adequate first aid supplies shall be readily available. Where the eyes or body of any person may be exposed to injurious corrosive materials, suitable facilities for quick drenching or flushing of the eyes and body shall be provided within the work area for immediate emergency use. First aid supplies are required to be readily available. An example of the minimal contents of a generic first aid kit is described in American National Standard (ANSI) Z308.1-1998 "Minimum Requirements for Workplace First-aid Kits." The contents of the kit listed in the ANSI standard should be adequate for small worksites. When larger operations or multiple operations are being conducted at the same location, employers should determine the need for additional first aid kits at the worksite, additional types of first aid equipment and supplies and additional quantities and types of supplies and equipment in the first aid kits. In a similar fashion, employers who have unique or changing first-aid needs in their workplace may need to enhance their first-aid kits. If it is reasonably anticipated that employees will be exposed to blood or other potentially infectious materials while using first aid supplies, employers are required to provide appropriate personal protective equipment (PPE). 3(l) Fire Protection 3(l)(1) Fire Brigades It is recommended that pre-fire planning be conducted by the local fire department and/or the workplace fire brigade in order for them to be familiar with the workplace and process hazards.

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Involvement with the local fire department or fire prevention bureau is encouraged to facilitate coordination and cooperation between members of the fire brigade and those who might be called upon for assistance during a fire emergency. Employees who cannot meet the physical capability requirement may still be members of the fire brigade as long as such employees do not perform interior structural fire fighting. It is suggested that fire brigade members who are unable to perform interior structural fire fighting be assigned less stressful and physically demanding fire brigade duties, e.g., certain types of training, recordkeeping, fire prevention inspection and maintenance, and fire pump operations. Physically capable can also be determined by physical performance tests or by a physical examination when the examining physician is aware of the duties that the fire brigade member is expected to perform. It is also recommended that fire brigade members participate in a physical fitness program. There are many benefits which can be attributed to being physically fit. It is believed that physical fitness may help to reduce the number of sprain and strain injuries as well as contributing to the improvement of the cardiovascular system. At a minimum, hands-on training is required to be conducted annually for all fire brigade members. However, for those fire brigade members who are expected to perform interior structural fire fighting, some type of training or education session must be provided at least quarterly. In addition to the required hands-on training, it is strongly recommended that fire brigade members receive other types of training and education such as: classroom instruction, review of emergency action procedures, pre-fire planning, review of special hazards in the workplace, and practice in the use of self-contained breathing apparatus. It is not necessary for the employer to duplicate the same training or education that a fire brigade member receives as a member of a community volunteer fire department, rescue squad, or similar organization. However, such training or education must have been provided to the fire brigade member within the past year and it must be documented that the fire brigade member has received the training or education. For example: there is no need for a fire brigade member to receive another training class in the use of positive-pressure self-contained breathing apparatus if the fire brigade member has recently completed such training as a member of a community fire department. Instead, the fire brigade member should receive training or education covering other important equipment or duties of the fire brigade as they relate to the workplace hazards, facilities and processes. It is generally recognized that the effectiveness of fire brigade training and education depends upon the expertise of those providing the training and education as well as the motivation of the fire brigade members. Fire brigade training instructors must receive a higher level of training and education than the fire brigade members they will be teaching. This includes being more knowledgeable about the functions to be performed by the fire brigade and the hazards involved.

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The instructors should be qualified to train fire brigade members and demonstrate skills in communication, methods of teaching, and motivation. It is important for instructors and fire brigade members alike to be motivated toward the goals of the fire brigade and be aware of the importance of the service that they are providing for the protection of other employees and the workplace. In order to be effective, fire brigades must have competent leadership and supervision. It is important for those who supervise the fire brigade during emergency situations, e.g., fire brigade chiefs, leaders, etc., to receive the necessary training and education for supervising fire brigade activities during these hazardous and stressful situations. These fire brigade members with leadership responsibilities should demonstrate skills in strategy and tactics, fire suppression and prevention techniques, leadership principles, pre-fire planning, and safety practices. It is again suggested that fire service training sources be consulted for determining the kinds of training and education which are necessary for those with fire brigade leadership responsibilities. Fire brigade leaders and fire brigade instructors should receive more formalized training and education on a continuing basis by attending classes provided by such training sources as universities and university fire extension services. The following recommendations should not be considered to be all of the necessary elements of a complete comprehensive training program, but the information may be helpful as a guide in developing a fire brigade training program. All fire brigade members should be familiar with exit facilities and their location, emergency escape routes for handicapped workers, and the workplace "emergency action plan." In addition, fire brigade members who are expected to control and extinguish fires in the incipient stage should, at a minimum, be trained in the use of fire extinguishers, standpipes, and other fire equipment they are assigned to use. They should also be aware of first aid medical procedures and procedures for dealing with special hazards to which they may be exposed. Training and education should include both classroom instruction and actual operation of the equipment under simulated emergency conditions. Hands-on type training must be conducted at least annually but some functions should be reviewed more often. In addition to the above training, fire brigade members who are expected to perform emergency rescue and interior structural fire fighting should, at a minimum, be familiar with the proper techniques in rescue and fire suppression procedures. Training and education should include fire protection courses, classroom training, simulated fire situations including "wet drills" and, when feasible, extinguishment of actual mock fires. Frequency of training or education must be at least quarterly, but some drills or classroom training should be conducted as often as monthly or even weekly to maintain the proficiency of fire brigade members. It is important that fire brigade members be informed about special hazards to which they may be exposed during fire and other emergencies. Such hazards as storage and use areas of flammable liquids and gases, toxic chemicals, water-reactive substances, etc., can pose difficult problems. There must be written procedures developed that describe the actions to be taken in situations

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involving special hazards. Fire brigade members must be trained in handling these special hazards as well as keeping abreast of any changes that occur in relation to these special hazards. 3(l)(2) Fire Fighting Equipment It is important that fire fighting equipment that is in damaged or unserviceable condition be removed from service and replaced. This will prevent fire brigade members from using unsafe equipment by mistake. Fire fighting equipment, except portable fire extinguishers and respirators, must be inspected at least annually. Portable fire extinguishers and respirators are required to be inspected at least monthly. It is not the intention of these standards to require employers to provide a full ensemble of protective clothing for every fire brigade member without consideration given to the types of hazardous environments to which the fire brigade member might be exposed. It is the intention of these standards to require adequate protection for those fire brigade members who might be exposed to fires in an advanced stage, smoke, toxic gases, and high temperatures. Therefore, the protective clothing requirements only apply to those fire brigade members who perform interior structural fire fighting operations. Additionally, the protective clothing requirements do not apply to the protective clothing worn during outside fire fighting operations (brush and forest fires, crash crew operations) or other special fire fighting activities. It is important that the protective clothing to be worn during these types of fire fighting operations reflect the hazards which are expected to be encountered by fire brigade members. Note that there is interdependence of protective clothing to cover one or more parts of the body. Therefore, an option is given so that fire brigade members may meet the foot and leg requirements by either wearing long fire-resistive coats in combination with fully extended boots, or by wearing shorter fire-resistive costs in combination with protective trousers and protective shoes or shorter boots. Fire-resistive coats and protective trousers meeting all of the requirements contained in NFPA 1971-1975 "Protective Clothing for Structural Fire Fighters," are acceptable as meeting the requirements of this standard. The lining is required to be permanently attached to the outer shell. However, it is permissible to attach the lining to the outer shell material by stitching in one area such as at the neck. Fastener tape or snap fasteners may be used to secure the rest of the lining to the outer shell to facilitate cleaning. Reference to permanent lining does not refer to a winter liner which is a detachable extra lining used to give added protection to the wearer against the effects of cold weather and wind. Hand protection may be met by protective gloves or a glove system. A glove system consists of a combination of different gloves. The usual components of a glove system consist of a pair of gloves, which provide thermal insulation to the hands, worn in combination with a second pair of gloves which provide protection against flame, cut, and puncture. III-53

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It is suggested that protective gloves provide dexterity and a sense of feel for objects. Criteria and test methods for dexterity are contained in the NIOSH publications, "The Development of Criteria for Firefighters' Gloves; Vol. I: Glove Requirements" and "Vol. II: Glove Criteria and Test Methods." These NIOSH publications also contain a permissible modified version of Federal Test Method 191, Method 5903, (paragraph (3) of Appendix E) for flame resistance when gloves, rather than glove material, are tested for flame resistance. Head protective devices which meet the requirements contained in NFPA No. 1972 are acceptable as meeting the requirements of this standard for head protection. Head protective devices are required to be provided with ear flaps so that the ear flaps will be available if needed. It is recommended that ear protection always be used while fighting interior structural fires. It is recommended that a flame resistant protective head covering such as a hood or snood, which will not adversely affect the seal of a respirator facepiece, be worn during interior structural fire fighting operations to protect the sides of the face and hair. Respiratory protection is required to be worn by fire brigade members while working inside buildings or confined spaces where toxic products of combustion or an oxygen deficiency is likely to be present; respirators are also to be worn during emergency situations involving toxic substances. When fire brigade members respond to emergency situations, they may be exposed to unknown contaminants in unknown concentrations. Therefore, it is imperative that fire brigade members wear proper respiratory protective devices during these situations. Additionally, there are many instances where toxic products of combustion are still present during mop-up and overhaul operations. Therefore, fire brigade members should continue to wear respirators during these types of operations. A self-contained breathing apparatus is not required to be equipped with either a buddybreathing device or a quick-disconnect valve. However, these accessories may be very useful and are acceptable as long as such accessories do not cause damage to the apparatus, restrict the air flow of the apparatus, or obstruct the normal operation of the apparatus. Buddy-breathing devices are useful for emergency situations where a victim or another fire brigade member can share the same air supply with the wearer of the apparatus for emergency escape purposes. The employer is encouraged to provide fire brigade members with an alternative means of respiratory protection to be used only for emergency escape purposes if the self-contained breathing apparatus becomes inoperative. Such alternative means of respiratory protection may be either a buddy-breathing device or an escape self-contained breathing apparatus (ESCBA). The ESCBA is a short-duration respiratory protective device which is approved for only emergency escape purposes. It is suggested that if ESCBA units are used, that they be of at least 5 minutes service life.

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Quick-disconnect valves are devices which start the flow of air by insertion of the hose (which leads to the facepiece) into the regulator of self-contained breathing apparatus, and stop the flow of air by disconnecting the hose from the regulator. These devices are particularly useful for those positive-pressure self-contained breathing apparatus which do not have the capability of being switched from the demand to the positive-pressure mode. The use of a self-contained breathing apparatus where the apparatus can be switched from a demand to a positive-pressure mode is acceptable as long as the apparatus is in the positivepressure mode when performing interior structural fire fighting operations. There are situations which require the use of respirators which have a duration of 2 hours or more. Presently, there are no approved positive-pressure apparatus with a rated service life of more than 2 hours. Consequently, negative-pressure self-contained breathing apparatus with a rated service life of more than 2 hours and which have a minimum protection factor of 5,000 as determined by an acceptable quantitative fit test performed on each individual, will be acceptable for use during situations which require long duration apparatus. Long duration apparatus may be needed in such instances as working in tunnels, subway systems, etc. Such negative-pressure breathing apparatus will continue to be acceptable for a maximum of 18 months after a positivepressure apparatus with the same or longer rated service life of more than 2 hours is certified by NIOSH/MSHA. After this 18 month phase-in period, all self-contained breathing apparatus used for these long duration situations will have to be of the positive-pressure type. Protection factor (sometimes called fit factor) is defined as the ratio of the contaminant concentrations outside of the respirator to the contaminant concentrations inside the facepiece of the respirator. Concentration outside respirator PF= -------------------------------Concentration inside facepiece Protection factors are determined by quantitative fit tests. An acceptable quantitative fit test should include the following elements: 1. A fire brigade member who is physically and medically capable of wearing respirators, and who is trained in the use of respirators, dons a self-contained breathing apparatus equipped with a device that will monitor the concentration of a contaminant inside the facepiece. 2. The fire brigade member then performs a qualitative fit test to assure the best face to facepiece seal as possible. A qualitative fit test can consist of a negative-pressure test, positive-pressure test, isoamyl acetate vapor (banana oil) test, or an irritant smoke test. 3. The wearer should then perform physical activity which reflects the level of work activity which would be expected during fire fighting activities. The physical activity should include simulated fire-ground work activity or physical exercise such as running-in-place, a step test, etc. 4. Without readjusting the apparatus, the wearer is placed in a test atmosphere containing a non-toxic contaminant with a known, constant, concentration.

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The protection factor is then determined by dividing the known concentration of the contaminant in the test atmosphere by the concentration of the contaminant inside the facepiece when the following exercises are performed: 1. Normal breathing with head motionless for one minute; 2. Deep breathing with head motionless for 30 seconds; 3. Turning head slowly from side to side while breathing normally, pausing for at least two breaths before changing direction. Continue for at least one minute; 4. Moving head slowly up and down while breathing normally, pausing for at least two breaths before changing direction. Continue for at least two minutes; 5. Reading from a prepared text, slowly and clearly, and loudly enough to be heard and understood. Continue for one minute; and 6. Normal breathing with head motionless for at least one minute. The protection factor which is determined must be at least 5,000. The quantitative fit test should be conducted at least three times. It is acceptable to conduct all three tests on the same day. However, there should be at least one hour between tests to reflect the protection afforded by the apparatus during different times of the day. The above elements are not meant to be a comprehensive, technical description of a quantitative fit test protocol. However, quantitative fit test procedures which include these elements are acceptable for determining protection factors. Procedures for a quantitative fit test are required to be available for inspection by the Assistant Secretary or authorized representative. 3(m) Handling Materials Where mechanical handling equipment is used, sufficient safe clearances shall be allowed for aisles, at loading docks, through doorways and wherever turns or passage must be made. Aisles and passageways shall be kept clear and in good repair, with no obstruction across or in aisles that could create a hazard. Permanent aisles and passageways shall be appropriately marked. Storage of material shall not create a hazard. Bags, containers, bundles, etc., stored in tiers shall be stacked, blocked, interlocked and limited in height so that they are stable and secure against sliding or collapse. Storage areas shall be kept free from accumulation of materials that constitute hazards from tripping, fire, explosion, or pest harborage. Vegetation control will be exercised when necessary. Clearance signs to warn of clearance limits shall be provided. Derail and/or bumper blocks shall be provided on spur railroad tracks where a rolling car could contact other cars being worked, enter a building, work or traffic area. Covers and/or guard- rails shall be provided to protect personnel from the hazards of open pits, tanks, vats, ditches, etc.

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3(n) Slings This section applies to slings used in conjunction with other material handling equipment for the movement of material by hoisting, in employments covered by this part. The types of slings covered are those made from alloy steel chain, wire rope, metal mesh, natural or synthetic fiber rope (conventional three strand construction), and synthetic web (nylon, polyester, and polypropylene). The following are important definitions. Angle of loading is the inclination of a leg or branch of a sling measured from the horizontal or vertical plane; provided that an angle of loading of five degrees or less from the vertical may be considered a vertical angle of loading. Basket hitch is a sling configuration whereby the sling is passed under the load and has both ends, end attachments, eyes or handles on the hook or a single master link. Braided wire rope is a wire rope formed by plaiting component wire ropes. Bridle wire rope sling is a sling composed of multiple wire rope legs with the top ends gathered in a fitting that goes over the lifting hook. Cable laid endless sling-mechanical joint is a wire rope sling made endless by joining the ends of a single length of cable laid rope with one or more metallic fittings. Cable laid grommet-hand tucked is an endless wire rope sling made from one length of rope wrapped six times around a core formed by hand tucking the ends of the rope inside the six wraps. Cable laid rope is a wire rope composed of six wire ropes wrapped around a fiber or wire rope core. Cable laid rope sling-mechanical joint is a wire rope sling made from a cable laid rope with eyes fabricated by pressing or swaging one or more metal sleeves over the rope junction. Choker hitch is a sling configuration with one end of the sling passing under the load and through an end attachment, handle or eye on the other end of the sling. Coating is an elastomer or other suitable material applied to a sling or to a sling component to impart desirable properties. Cross rod is a wire used to join spirals of metal mesh to form a complete fabric. Designated means selected or assigned by the employer or the employer's representative as being qualified to perform specific duties. Equivalent entity is a person or organization (including an employer) which, by possession of equipment, technical knowledge and skills, can perform with equal competence the same repairs and tests as the person or organization with which it is equated. III-57

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Fabric (metal mesh) is the flexible portion of a metal mesh sling consisting of a series of transverse coils and cross rods. Female handle (choker) is a handle with a handle eye and a slot of such dimension as to permit passage of a male handle thereby allowing the use of a metal mesh sling in a choker hitch. Handle is a terminal fitting to which metal mesh fabric is attached. Handle eye is an opening in a handle of a metal mesh sling shaped to accept a hook, shackle or other lifting device. Hitch is a sling configuration whereby the sling is fastened to an object or load, either directly to it or around it. Link is a single ring of a chain. Male handle (triangle) is a handle with a handle eye. Master coupling link is an alloy steel welded coupling link used as an intermediate link to join alloy steel chain to master links. Master link or gathering ring is a forged or welded steel link used to support all members (legs) of an alloy steel chain sling or wire rope sling. Mechanical coupling link is a nonwelded, mechanically closed steel link used to attach master links, hooks, etc., to alloy steel chain. Proof load is the load applied in performance of a proof test. Proof test is a nondestructive tension test performed by the sling manufacturer or an equivalent entity to verify construction and workmanship of a sling. Rated capacity or working load limit is the maximum working load permitted by the provisions of this section. Reach is the effective length of an alloy steel chain sling measured from the top bearing surface of the upper terminal component to the bottom bearing surface of the lower terminal component. Selvage edge is the finished edge of synthetic webbing designed to prevent unraveling. Sling is an assembly which connects the load to the material handling equipment. Sling manufacturer is a person or organization that assembles sling components into their final form for sale to users. Spiral is a single transverse coil that is the basic element from which metal mesh is fabricated.

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Strand laid endless sling-mechanical joint is a wire rope sling made endless from one length of rope with the ends joined by one or more metallic fittings. Strand laid grommet-hand tucked is an endless wire rope sling made from one length of strand wrapped six times around a core formed by hand tucking the ends of the strand inside the six wraps. Strand laid rope is a wire rope made with strands (usually six or eight) wrapped around a fiber core, wire strand core, or independent wire rope core (IWRC). Vertical hitch is a method of supporting a load by a single, vertical part or leg of the sling. Whenever any sling is used, the following practices shall be observed: • • • • • • • • • • • •

Slings that are damaged or defective shall not be used. Slings shall not be shortened with knots or bolts or other makeshift devices. Sling legs shall not be kinked. Slings shall not be loaded in excess of their rated capacities. Slings used in a basket hitch shall have the loads balanced to prevent slippage. Slings shall be securely attached to their loads. Slings shall be padded or protected from the sharp edges of their loads. Suspended loads shall be kept clear of all obstructions. All employees shall be kept clear of loads about to be lifted and of suspended loads. Hands or fingers shall not be placed between the sling and its load while the sling is being tightened around the load. Shock loading is prohibited. A sling shall not be pulled from under a load when the load is resting on the sling.

Each day before being used, the sling and all fastenings and attachments shall be inspected for damage or defects by a competent person designated by the employer. Additional inspections shall be performed during sling use, where service conditions warrant. Damaged or defective slings shall be immediately removed from service. Alloy steel chain slings shall have permanently affixed durable identification stating size, grade, rated capacity, and reach. Table 10 in this section shows the rated capacity (working load limit), for alloy steel chain slings. Table 11 in this section lists the minimum allowable chain size at any point of link. Hooks, rings, oblong links, pear shaped links, welded or mechanical coupling links or other attachments shall have a rated capacity at least equal to that of the alloy steel chain with which they are used or the sling shall not be used in excess of the rated capacity of the weakest component. Makeshift links or fasteners formed from bolts or rods, or other such attachments, shall not be used.

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A thorough periodic inspection of alloy steel chain slings in use shall be made on a regular basis, to be determined on the basis of (A) frequency of sling use; (B) severity of service conditions; (C) nature of lifts being made; and (D) experience gained on the service life of slings used in similar circumstances. Such inspections shall in no event be at intervals greater than once every 12 months. The employer shall make and maintain a record of the most recent month in which each alloy steel chain sling was thoroughly inspected, and shall make such record available for examination. The thorough inspection of alloy steel chain slings shall be performed by a competent person designated by the employer, and shall include a thorough inspection for wear, defective welds, deformation and increase in length. Where such defects or deterioration are present, the sling shall be immediately removed from service. The employer shall ensure that before use, each new, repaired, or reconditioned alloy steel chain sling, including all welded components in the sling assembly, shall be proof tested by the sling manufacturer or equivalent entity. The employer shall retain a certificate of the proof test and shall make it available for examination. Alloy steel chain slings shall not be used with loads in excess of the rated capacities. Alloy steel chain slings shall be permanently removed from service if they are heated above 537.8 degrees Celsius. When exposed to service temperatures in excess of 315.6 degrees Celsius, maximum working load limits permitted by the supplier shall be reduced in accordance with the chain or sling manufacturer's recommendations. Worn or damaged alloy steel chain slings or attachments shall not be used until repaired. When welding or heat testing is performed, slings shall not be used unless repaired, reconditioned and proof tested by the sling manufacturer or an equivalent entity. Mechanical coupling links or low carbon steel repair links shall not be used to repair broken lengths of chain. Alloy steel chain slings with cracked or deformed master links, coupling links or other components shall be removed from service.

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Table 10. Rated Capacity (Working Load Limit), For Alloy Steel Chain Slings Rated Capacity (Working Load Limit), Newton Meters [Horizontal angles shown in parentheses]

Chain size, cm

0.64 0.38 1.27 1.59 1.91 2.22 2.54 2.86 3.18 3.50 3.81 4.45

Single Double sling vertical angle (1) branch sling -- 90º 30º 45º 60º loading (60º) (45º) (30º) 4,406 7,660 6,169 4,406 8,948 15,456 12,609 8,948 15,253 26,438 21,558 15,253 22,371 38,641 31,590 22,371 31,184 53,961 44,064 31,184 38,980 67,520 55,046 38,980 52,538 90,976 7,864 52,538 60,334 104,398 85,417 60,334 77,960 134,904 82,705 77,960 90,840 157,275 127,447 90,840 108,466 187,103 153,072 108,466 135,582 233,201 189,815 135,582

Triple and quadruple sling (3) vertical angle (1) 30º 45º 60º (60º) (45º) (30º) 11,389 9,220 6,644 23,049 18,981 13,423 39,319 32,540 23,049 58,300 47,454 33,218 80,671 65,757 46,776 101,008 82,705 58,300 136,938 111,177 78,638 156,597 128,125 90,162 202,017 164,732 116,601 235,913 191,170 136,260 280,655 229,134 162,020 349,802 284,722 203,373

(1) Rating of multileg slings adjusted for angle of loading measured as the included angle between the inclined leg and the vertical as shown in Figure N-184-5. (2) Rating of multileg slings adjusted for angle of loading between the inclined leg and the horizontal plane of the load, as shown in Figure N-184-5. (3) Quadruple sling rating is same as triple sling because normal lifting practice may not distribute load uniformly to all 4 legs. Table 11. Minimum Allowable Chain Size at Any Point Of Link

Chain size, mm

Minimum allowable chain size, mm

6.4 3.8 12.7 15.9 19.1 22.2 25.4 28.6 31.8 35 38.1 44.5

5.6 7.5 9.9 12.3 15.1 18 20.7 23 25.4 27.8 30.8 35.7

Source: OSHA Standard 1910.184

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Wire rope slings shall not be used with loads in excess of the rated capacities shown in Tables N184-3 through N-184-14. Slings not included in these tables shall be used only in accordance with the manufacturer's recommendations. Cable laid and 6x19 and 6x37 slings shall have a minimum clear length of wire rope 10 times the component rope diameter between splices, sleeves or end fittings. Braided slings shall have a minimum clear length of wire rope 40 times the component rope diameter between the loops or end fittings. Cable laid grommets, strand laid grommets and endless slings shall have a minimum circumferential length of 96 times their body diameter. Fiber core wire rope slings of all grades shall be permanently removed from service if they are exposed to temperatures in excess of 93.3 degrees Celsius. When nonfiber core wire rope slings of any grade are used at temperatures above 204.4 degrees Celsius or below minus 51.1 degrees Celsius, recommendations of the sling manufacturer regarding use at that temperature shall be followed. Welding of end attachments, except covers to thimbles, shall be performed prior to the assembly of the sling. All welded end attachments shall not be used unless proof tested by the manufacturer or equivalent entity at twice their rated capacity prior to initial use. The employer shall retain a certificate of the proof test, and make it available for examination. 3(o) Bibliography American National Standard (ANSI) Z308.1-1998 "Minimum Requirements for Workplace First-aid Kits." American Society for Testing and Materials (ASTM) D 120-87, Specification for Rubber Insulating Gloves. ASTM D 178-93 (or D 178-88), Specification for Rubber Insulating Matting. ASTM D 1048-93 (or D 1048-88a), Specification for Rubber Insulating Blankets. ASTM D 1049-93 (or D 1049-88), Specification for Rubber Insulating Covers. ASTM D 1050-90, Specification for Rubber Insulating Line Hose. ASTM D 1051-87, Specification for Rubber Insulating Sleeves. ANSI Safety Code for Building Construction, A10.2-1944.

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Guide for the Selection of Chemical and Biological Decontamination Equipment for Emergency First Responders. National Institute of Justice Guide 103-00, Volume I, October 2001. The Development of Criteria for Firefighters' Gloves; Vol. I: Glove Requirements. The Development of Criteria for Firefighters' Gloves; Vol. II: Glove Criteria and Test Methods. U.S. Department of Labor, Occupational Safety and Health Administration, Hazardous Waste Operations and Emergency Response (HAZWOPER) Standard (29 CFR 1910.120(q).

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Annex A Accident Investigation The following materials have been obtained from The Tennessee Valley Authority (TVA), Reference Document Procedure No. 111, Revision 4, November 01, 2005.

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Conduct Serious Accident Investigation 1.

Purpose

1.1.

TVA-SPP-18.010, Conduct Serious Accident Investigation establishes a process for investigating and reporting serious accidents.

1.2.

TVA-SPP-18.010, Conduct Serious Accident Investigation is attached.

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TITLE TVA STANDARD CONDUCT SERIOUS ACCIDENT INVESTIGATION PROGRAMS AND PROCESSES

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TVA-SPP-18.010 Rev. 4 11/01/05 Page 1 OF 32

Effective Date 12/01/05

RESPONSIBLE PEER TEAM:

Safety Process Ownership Team Responsible Peer Team

CONCURRENCES

Phillip L. Reynolds VP, COO Operations Support

11/01/05 Date

APPROVAL John E. Long, Jr. Designated Agency Safety and Health Official

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REVISION LOG Revision Effective Pages Number Date Affected Description of Revision 0 Initial issue in this format. Supersedes “Implementing Criteria for 08/06/02 All Serious Accident Investigation,” Revision 03, July 22, 1998

1

08/01/03

2

04/16/04

10 & 11

Retraining requirement in paragraph 3.2.2 B deleted and employee representative added to the Accident Investigation Team in paragraph 3.2.2.D.3. 1. Paragraph 3.1, TVA Police (TVAP), “C.” and Paragraph 3.2.B.3.c. revised to clarify the type of communications provided by TVAP 2. Paragraph 3.1, revised to add roles and responsibilities for Environmental Policy and Planning. 3. Paragraph 3.2.B. revised to add title of Appendix B. 4. Paragraph 3.2.B.4.d. revised to add requirement to document the name of individual(s) transported to medical facilities to include the name of the facility. 5. Paragraph 3.2.1.E. added to include responsibilities of Environmental Policy and Planning. 6. Paragraph 3.2.1.F. changed Vice President of Communications to Vice President of External Communications. 7. Paragraph 3.2.2.A. deleted requirement to train non-management employees as serious accident investigation team members. 8. Paragraph 3.2.2.D. deleted requirement for an employee member on the serious accident investigation team. 9. Paragraph 3.2.2.E.1. and 3. adds Environmental Serious Accident Investigation Team. 10. Paragraph 5, definition of cause-and-effect diagram, deleted the example diagram. 11. Paragraph 5, definition of Corporate Safety changed to reflect current organization. 12. Appendix C, Paragraph 2.3.G. revised to show current Employee Assistance Program contacts. 13. Appendix C, Paragraph 2.3.H. changed Vice President of Communications to Vice President of External Communications. 14. Appendix C, Paragraph 2.3.I. added notification of the Vice President, Environmental Policy and Planning.

3

12/05/04

Updated phone numbers in Appendix C

4

12/01/05

Updated phone numbers in Appendix C

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TABLE OF CONTENTS 1.

1.0 PURPOSE............................................................................................................ III-71

2.

2.0 SCOPE ................................................................................................................. III-71

3.

3.0 PROCESS ............................................................................................................ III-71

3.1 3.2

Roles and Responsibilities ........................................................................................... III-71 Instructions................................................................................................................... III-75

4.0

RECORDS ................................................................................................................ III-83

4.1 4.2

QA Record .................................................................................................................. III-83 Non-QA Records ......................................................................................................... III-84

5.0 DEFINITIONS ................................................................................................................ III-85 APPENDIX A - PROCESS FLOW CHART AND CONTROL SYSTEM ..................... III-88 APPENDIX B - CHECKLIST OF INITIAL ACTIONS FOR MANAGER IN CHARGE OF THE WORKPLACE WHERE A SERIOUS ACCIDENT OCCURS...................... III-90 APPENDIX C - SERIOUS ACCIDENT NOTIFICATION CONTACT LIST .............. III-91 APPENDIX D - SAMPLE ACCIDENT INVESTIGATION TEAM CHARTER .......... III-93 APPENDIX E - SAMPLE ACCIDENT REPORT ............................................................ III-96 APPENDIX F - ACCIDENT ANALYSIS REPORT FORMAT ...................................... III-99

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CONDUCT SERIOUS ACCIDENT INVESTIGATION 1.0

PURPOSE

NOTE 1 The intent of this process is not to place blame on individuals or organizations. The objective of this process is to establish a method for:

2.0

A.

Identifying root causes/contributing factors of serious accidents that may occur in TVA.

B.

Recommending actions to prevent recurrence.

SCOPE This process applies to all TVA employees.

3.0

PROCESS The quality indicator for this process is the number of root causes from serious accident investigation reports that are identified from analysis of Work Injury/Illness System (WIIS) data. (Q1) The following criteria are used to evaluate the efficiency and effectiveness of this process. In addition to Q1, process indicators shown in bold italic are tracked and results reported periodically to management. A.

3.1

Percent of accident investigation team (AIT) members having completed TVA University (TVAU) Course # 00013146, “Serious Accident Investigation.” (P1) B. “Accident Report” prepared within five workdays of the event. (P2) C. Form TVA 18120, TVA Injury/Illness Investigation Report, provided to the Employee Service Center (ESC) within 10 workdays of the event. (P3) D. “Accident Analysis Report” prepared within 30 workdays of the event. (P4) E. The responsible executive vice president (EVP) and Designated Agency Safety and Health Official (DASHO) briefed within 45 workdays of the event. (P5) F. Workplace employees briefed within 60 workdays of the event. (P6) G. Corrective action implemented by date on the solutions matrix and action plan. (P7) H. Investigation findings analyzed annually. (P8) I. Process effectiveness evaluated at least every three years. (P9) Roles and Responsibilities Designated Agency Safety and Health Official (DASHO)/Corporate Safety A.

B. C. D. E.

Notifies the Occupational Safety and Health Administration (OSHA), various TVA managers, and the appropriate labor representative of the occurrence of an event. DASHO jointly appoints AIT with responsible EVP. Provides an AIT member to serve as the DASHO’s representative. Prepares AIT charter. DASHO jointly approves AIT charter with responsible EVP.

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F. G. H.

Reviews “Accident Report.” Reviews “Accident Analysis Report.” Participates in “EVP/DASHO” briefing and, as appropriate, documents differing opinion(s) for attachment to “Accident Analysis Report.” I. Participates in briefing for Chief Operating Officer (COO) for events occurring in that organization. J. Assists with briefings for other employee groups, upon request. K. Distributes the “Accident Analysis Report” to the Board, other TVA managers, labor representative(s), and OSHA subsequent to completion of briefings. L. Briefs OSHA on the event. M. Provides assistance with implementation of “Accident Analysis Report” recommendations, upon request. N. Tracks implementation of recommendations to closure. O. Follows up, as necessary to review status and effectiveness of implementation of recommendations. P. Resolves issues at the appropriate level of management, as necessary. Q. Closes the investigation upon satisfactory completion of recommendations. R. Retains AIT documentation. S. Periodically analyzes and summarizes TVA’s serious accident experience to identify trend and causal information and reports results to management. T. Serves as the “owner” for WIIS. U. Approves and publishes this process. V. Tracks performance. W. Assesses process effectiveness at least every three years. Primary Sponsor Chairs the TVA Safety Program Process Improvement Team and recommends changes in this process to the DASHO. TVA Safety Program Process Improvement Team Receives, reviews, evaluates, and recommends action proposed by employees on suggested improvements to this process. Chief Operating Officer (COO) or Executive Vice Presidents (EVP) A. B. C. D. E. F.

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Notifies Board and, as appropriate, responsible chief officer. Jointly appoints AIT with DASHO. Jointly approves AIT charter with DASHO. Reviews “Accident Report.” Reviews “Accident Analysis Report.” Participates in “EVP/DASHO” briefing and, as appropriate, documents differing opinion(s) for attachment to “Accident Analysis Report.”

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G.

Participates in briefing for Chief Operating Officer (COO) for events occurring in that organization. H. Concurs with recommendations. I. Briefs other employee groups. J. Ensures effective and timely implementation of recommendations. K. Replicates recommendations, as appropriate. L. Documents action taken/planned on all recommendations. M. Prepares a timetable for execution of recommendations that remain open beyond 60 calendar days. N. Provides status reports to the DASHO according to the timetable. O. Participates in resolution of issues at the appropriate level of management, as necessary. P. Reviews analysis of TVA’s serious accident experience and internalizes and replicates results, as appropriate. Q. Periodically evaluates process effectiveness. Manager in Charge of Workplace A.

Provides care for injured employee(s) and controls residual hazard(s) upon occurrence of an event. B. Secures the accident scene. C. Identifies witnesses and obtains written statements. D. Notifies appropriate management. E. Completes the checklist of initial actions (Appendix B). F. Completes form TVA 18119, Tennessee Valley Authority Work Injury/Illness Log. G. Assists with implementation of and/or follow-up on approved recommendations. H. Reviews the analysis of TVA’s serious accident experience and internalizes and replicates results, as appropriate. I. Periodically evaluates process effectiveness. TVA Police (TVAP)

A. B. C. D. E. F. G. H. I.

Secures the accident scene. Coordinates with emergency service and other law enforcement agencies. Provides communication methods/equipment for the AIT when required. Obtains witness statements. Collects, maintains, and provides chain of custody for physical evidence. Photographs the accident scene. Provides other support to the AIT, as requested. Provides a summary of actions taken to support the AIT. Periodically evaluates process effectiveness.

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Communications and Government Relations Appoints a spokesperson to serve as liaison between the AIT and media and periodically evaluates process effectiveness. Environmental Policy and Planning Determines if adverse environmental impacts may result from the accident and provides relevant and/or pertinent information to Corporate Safety concerning issues that could affect the safety of the AIT or other employees. Ensures that TVA resources, especially technical expertise, are available for preventing or mitigating adverse impacts to the environment. Accident Investigation Team (AIT) A. B. C. D. E. F. G. H. I.

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Conducts investigation. Requests support, assistance, and/or subject matter expertise to complete the investigation, as required. Prepares the “Accident Report.” Prepares form TVA 18120. Prepares the “Accident Analysis Report.” Provides the “EVP/DASHO” briefing. Provides a briefing for the COO for events occurring in that organization. Assembles material generated/collected during the investigation and provides to the DASHO/Corporate Safety for retention. Identifies “lessons learned” from participating in the process and provides to the DASHO/Corporate Safety.

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3.2

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Instructions

NOTE 2 Regulatory and other “drivers” for this process include the following. A.

Executive Order 12196, “Occupational Safety and Health Programs for Federal Employees” (requires heads of federal agencies to comply with basic program elements issued by the Secretary of Labor). B. 29 CFR 1960, “Basic Program Elements for Federal Employee Occupational Safety and Health Programs and Related Matters” (requires the development of this process [1960.6] and establishes OSHA requirements for investigating serious accidents [1960.29 and 1960.70]). C. TVA Principles and Practices, Health and Safety Practice 2, Safety (outlines TVA’s overall safety program, including provisions for investigating serious accidents). D. TVA-SPP-18.0, “TVA Safety Program” (describes key features of TVA’s safety program, including requirements for investigating serious accidents). E. TVA-SPP-18.012, “Report and Investigate Injuries and Illnesses" (defines TVA requirements for reporting and investigating injuries and illnesses). F. TVA Quality Improvement Tools and Techniques Reference Manual (describes methods for conducting root cause analysis, determining solutions and action items, etc.) NOTE 3 Parenthesis (xx) in the paragraph headings that follow refer to symbols shown in the flow chart and control system for this process which are included as Appendix A. 3.2.1

Report Serious Accidents (A1 - A7 and A10 - A11) A.

Serious accidents include any of the following occurrences. 1.

A fatality or in-patient hospitalization of three or more TVA employees within 30 days of an accident.

2.

Other events (including property damage only) which under slightly different circumstances would have met or may meet the provisions of paragraph 3.2.1A1. The DASHO and affected EVP will determine if events meeting this criteria will be investigated.

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EXAMPLE •

Typical events of the type intended in paragraph 3.2.1A2 include those resulting from:

•

Falls (usually from elevation) causing head injury, broken bones, and/or other serious injury.

•

Electric contact resulting in current flow through the body and/or loss of consciousness.

•

Electric arc causing second- and/or third-degree burns to the body.

•

Being caught in or by equipment/machinery causing head injury, broken bones, and/or other serious injury.

•

Thermal burns causing second and/or third degree burns to the body.

•

Being struck by equipment/machinery or falling objects causing head injury, broken bones, and/or other serious injury.

•

Overpressure (gas, hydraulic, or air) causing head injury, broken bones, and/or other significant traumatic injury.

•

Release of latent or kinetic energy (tension [objects under compression] or projectiles [objects being thrown]) causing head injury, broken bones, and/or other serious injury.

B.

1

If an event meeting the requirements of paragraph 3.2.1A occurs, the manager in charge of the workplace1: (See Appendix B, “Checklist of Initial Actions for Manager in Charge of the Workplace Where a Serious Accident Occurs”) 1.

Ensures that energy sources or other hazardous conditions are controlled to prevent additional injuries and/or property damage.

2.

Responds to the needs of the injured employee(s).

3.

Secures the accident scene to protect people and property from any hazards associated with the accident and to prevent disturbance of evidence until the scene is released by the AIT chairperson. TVAP2 is notified by Corporate Safety to assist with: a.

Securing the scene to preclude entry of unauthorized personnel.

b.

Coordinating with emergency service and law enforcement agencies.

c.

Providing communication methods/equipment for the AIT when required

d.

Obtaining witness statements.

e.

Collecting, maintaining, and tracking evidence.

f.

Photographing the accident scene.

Requirements in paragraphs 3.2.1B1 - 3.2.1B6 are listed in the general order of preference. However, many of these requirements can be carried out simultaneously. 2 Upon completion of the investigation, TVAP will prepare a summary of actions taken to support this activity and offer suggestions for improving this process.

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Part III: Worker Safety Rules

In accordance with paragraph 2.1 of Appendix C, Notifies the responsible EVP, safety manager of the responsible TVA organization, and Corporate Safety3 of: a

The accident location.

b.

The accident time.

c.

The name(s) of the individual(s) involved.

d.

The extent and nature of injuries. Name of individual(s) transported to medical facilities to include the name of the facility.

e.

The name and telephone number of a contact person at the accident location.

f.

A brief description of the event.

5.

After the notifications in paragraph 3.2.1B4 occur, each organization will follow its procedure for notifying family members.

6.

Identify all witnesses to the accident.4

C.

The responsible EVP notifies the Board5, COO, and others as listed in paragraph 2.2 of Appendix C.

D.

Corporate Safety notifies those listed in paragraph 2.3 of Appendix C.

E.

The Vice President, Environmental Policy and Planning, coordinates with Corporate Safety on environmental issues and the need for involvement in the serious accident investigation.

F.

The Vice President, External Communications, selects a spokesperson to serve as liaison between the AIT and the media during the investigation.

G.

Events of the following types require notification by the manager in charge of the workplace and others as described above but are not investigated using this process. These events include: 1.

A fatality to a TVA employee during non-work status.

2.

A serious accident involving contractor employee(s) only unless the DASHO and affected EVP determine that an investigation will be conducted.

3.

Fatalities to members of the public on TVA property.

4.

Radiological control and nuclear operational safety incidents subject to other reporting and investigation requirements. These events are investigated by TVA Nuclear.

3

Corporate Safety must be notified as soon as possible so this process can be initiated immediately and to allow TVA to comply with its reporting requirement to OSHA. 4 Provide the list of potential witnesses to the responding TVAP officer(s) so statements can be obtained. 5 EVPs in the COO organization will notify the President and COO who subsequently notifies the Board.

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3.2.2

Appoint AIT (A8) A.

Corporate Safety maintains a list of currently qualified managers that are trained in accident investigation methodology (TVAU Course # 00013146, “Serious Accident Investigation Training”). This list is maintained on the “Safety Home Page.”

B.

To be qualified to serve as an AIT member, an individual must complete TVAU Course 00013146.

C.

AIT members are appointed from among those meeting the requirements of paragraph 3.2.2B. Discussion will occur prior to appointing someone as an AIT member to ensure that the individual will be able to participate, on essentially an uninterrupted basis, for four - six weeks.(P1)

D.

Once appropriate notifications are complete, the DASHO and responsible EVP jointly appoint members of the AIT to include:

E.

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1.

A line manager to serve as chairperson. This manager will not have line responsibility for the organization where the accident occurred.

2.

One line manager from the organization in which the accident occurred.

3.

The safety manager for the responsible TVA organization.

4.

A line manager from an organization other than that where the accident occurred.

5.

An individual who represents the DASHO during the investigation. In addition to team member responsibilities, this individual interprets this process and provides advice relative to accident investigation techniques.

The AIT chairperson determines whether to request advisors or other assistance to support team needs. Chairpersons should consider requesting assistance from: 1.

The Office of the Inspector General (OIG), Office of the General Counsel (OGC), Environmental Policy and Planning, and/or the TVAP if there are indications of misconduct or violations of law or other reasons warranting participation by one or more of these organizations.

2.

TVAP to investigate fire loss.

3.

Environmental Policy and Planning for assistance relative to environmental issues.

4.

Others with appropriate subject matter expertise, such as consultants or fire protection engineers. If the services of advisor(s) are secured, they perform tasks assigned by the chairperson. They provide results of studies, tests, examinations, etc., to the chairperson and respond to questions from the AIT.

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3.2.3

3.2.4

Prepare AIT Charter (A9, D1) A.

Corporate Safety prepares a charter for the AIT for approval by the DASHO and responsible EVP.

B.

The charter identifies the AIT chairperson, membership, authority, scope, schedule, short code6, and any special instructions. See Appendix D for a sample charter.

Conduct Investigation (A12) A.

B.

The investigation’s scope includes: 1.

A complete determination and thorough analysis of the facts, circumstances, and conditions related to the accident (“Who?,” “When?,” “What?,” “Where?,” and “How?”).

2.

Identification of factors that caused or contributed to the accident (“Why?”).

3.

Determination and evaluation of actions necessary to minimize recurrence of this or similar events.

The methodology used by the AIT in conducting the investigation includes: 1.

Reporting to the scene as soon as possible, usually no later than the day after the accident.

2.

Discussing and emphasizing directions in the charter with the responsible EVP and DASHO, once assembled on-site.

3.

A briefing by the AIT chairperson to team members on:

4.

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a.

The investigation’s purpose, scope, deliverables, time constraints, etc.

b.

What should and should not be discussed beyond the team.

b.

Background and preliminary accident details.

c.

Status of the accident scene (security, existing hazardous conditions, necessary precautions, personal protective equipment needed, operational needs for the investigation, etc.)

d.

Arrangements for clerical and other administrative support.

Developing an improvement activity (IA) summary7 consistent with the six-step problem solving process (reference 3.2F) to arrive at its opinions and recommended solutions. The Cause and Effect Diagram or Events and Causal Factors Chart are analytical techniques to be used in the investigation. Material such as the sequence of events, problem statement, cause and effect diagram, root cause verification matrix, and

The responsible EVP will provide a short code for all non-salary expenses incurred by the AIT. The IA summary addresses steps 1 - 4.

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solutions matrix and action plan documents generated by the AIT will be included as an attachment to the “Accident Analysis Report.”

3.2.5

Securing, classifying, and maintaining physical evidence according to TVAP procedures.

6.

Documenting interviews. Corporate Safety arranges to have interviews recorded in an attempt to maximize the quality of data collected and minimize note-taking by members.

Prepare And Distribute Reports (A13 - A17, A27, and T1) A.

The AIT completes th e ‘Accident Report” within five workdays of the event. (P2)

B.

The “Accident Report” contains o nly factual informa tion and may be released for public use, with approval of the DASHO and responsible EVP. A sample report is included as Appendix E.

C.

The AIT chairperson sends the “Accident Report” to the DASHO and responsible EVP. Copies of this report are provided to those shown in Appendix E and posted on the “Safety Home Page.”

D.

The AIT chairperson completes a form TVA 18120 within 10 workdays of the event and signs it as the “Reviewing Official.” (P3) This form is submitted to ESC for entry into WIIS (paragraph 3.2.5F, TVA-SPP-18.012). If necessary, this form is revised upon completion of the investigation to include any information that was not available when it was initially completed.

E.

The manager in charge of the workplace completes form TVA 18119 and submits it to Corporate Safety for entry into WIIS (paragraph 3.2.4G, TVASPP-18.012).

F.

An “Accident Analysis Report” is completed by the AIT within 30 workdays of the event. The AIT prepares a narrative analysis report that includes:

G.

8

5.

1.

An executive summary.

2.

A timeline of key events.

3.

A description of the accident.

4.

Findings, conclusions, recommendations/corrective actions8.

5.

Appropriate attachments such as photos/drawings, related documentation, etc.

The “Accident Analysis Report:” 1.

Provides an in-depth analysis of the accident to identify root causes and contributing factors.

2.

Considers all possible physical and programmatic causes.

If during the investigation a clear need to develop a new or modify an existing safety process/procedure is identified, the AIT chairperson will provide the DASHO an interim recommendation. The DASHO will coordinate corrective action in accordance with TVA SPP 18.001 - Develop Safety Program Documentation

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Part III: Worker Safety Rules

3.

Identifies all root causes and contributing factors.

4.

Includes the final listing of the AIT’s opinions and recommendations

5.

Provides a list of actions required to achieve recommended solutions (activities required).

6.

Contains any dissenting opinions among AIT members that cannot be resolved, as an attachment to the report.

7.

Is classified “Sensitive.”

H.

An “Accident Analysis Report” format is included as Appendix F.

I.

If 30 workdays is not feasible for completion of the “Accident Analysis Report,” an extension must be approved by the responsible EVP and the DASHO. (P4)

J.

The AIT chairperson sends the “Accident Analysis Report” to the responsible EVP and direct report that manages the organization where the accident occurred; DASHO; and Manager, Health, Safety & Workers’ Compensation (HS&WC), with a copy to the COO, if the event occurred in that organization.

K.

Copies of the “Accident Analysis Report” are numbered for control. No additional copies are made unless approved by the DASHO and responsible EVP.

L.

The AIT identifies “lessons learned” from the investigation and provides them to the DASHO.

Conduct Briefings (A18 - A20, A22, A24, and D2) A.

The AIT prepares briefing material that includes: 1.

A sequence of events.

2.

The problem statement.

3.

An overview of the cause and effect diagram.

4.

Root cause verification matrix.

5.

Solutions matrix and action plan.

NOTE 4 If the EVP or DASHO have differing opinions from those presented in the briefing described in paragraph 3.2.6B, those views are documented and attached to the “Accident Analysis Report.” B.

The AIT schedules and provides a briefing for the responsible EVP and the DASHO within 45 days of the event. (P5) The EVP and DASHO may invite others to attend the briefing, as they determine to be appropriate.

C.

For those events occurring in the COO, the AIT chairperson accompanied by the EVP and DASHO uses the material developed in paragraph 3.2.6A to brief the President and COO.

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3.2.7

3.2.8

3.2.9

3.2.10

D.

The purpose of this briefing is to provide the findings and conclusions and obtain concurrence on the recommendations.

E.

The EVP ensures that management, the local health and safety committee, and employees at the facility/site where the accident occurred are provided the briefing outlined in paragraph 3.2.6A within 60 workdays of the event. This briefing may be provided to other work groups within the organization, as necessary. (P6)

F.

The DASHO/Corporate Safety uses the material developed in paragraph 3.2.6A to brief OSHA.

Share Information (A23, A25, and D3) A.

If investigation results are applicable to other TVA employees, additional briefings using the material developed in paragraph 3.2.6A may be required. Corporate Safety provides necessary support, coordination, and information for these briefings.

B.

After these briefings have been provided, the DASHO sends copies of the “Accident Analysis Report” to the Board, other EVPs, safety managers of TVA organizations, manager in charge of the workplace, appropriate labor representative(s), and OSHA. These reports are transmitted with a cover memorandum that establishes limits regarding further distribution. A copy of this memorandum is provided to the responsible EVP.

Implement Recommendations (A26) A.

The responsible EVP ensures timely and effective implementation of recommendations in the “Accident Analysis Report.”

B.

The responsible EVP reviews the recommendations for replication opportunities within his/her organization and implements appropriate corrective action.

C.

Other EVPs also review the recommendations for replication opportunities and implement appropriate corrective action within their organizations.

D.

The DASHO provides assistance, as needed, and monitors related activities to ensure adequate sharing of information.

Maintain Records (A21 and A27) A.

Upon completion of the briefings, the AIT chairperson sends all accident investigation materials and evidence to Corporate Safety.

B.

Corporate Safety retains all original documentation generated or collected by the AIT during the investigation in the agency’s serious accident repository.

C.

Release of any of this material requires authorization by the DASHO.

Track Recommendations To Closure (A28) A.

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The responsible EVP:

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B.

C.

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1.

Documents9 action taken/planned on each recommendation and provides to the DASHO/Corporate Safety within 60 calendar days of the final report date.

2.

Develops and includes a timetable for any recommendation that remains open beyond 60 calendar days following the final report date. This timetable is included with the documentation required by paragraph 3.2.10A.

3.

Provides status, based on the timetable, as each abatement date is reached until all recommendations are implemented. (P7)

Corporate Safety: 1.

Tracks each recommendation until all are satisfactorily closed.

2.

Conducts follow-ups which may include site visits to review recommendation status or effectiveness of implementation.

Any issues regarding action taken to implement recommendations that can not be resolved with Corporate Safety are elevated to the DASHO for resolution with the appropriate level of management.

Close Investigation (D4) When all recommendations are considered complete, the DASHO sends a memorandum to those that received a copy of the “Accident Analysis Report” to close the investigation.

3.2.12

3.2.13

Analyze Investigation Findings (A29 - A30, D5, and T2) A.

Serious accident investigation results are analyzed periodically to identify trends and causal information. This information is reported to management. (P8)

B.

Results of this analysis are also used to determine areas of emphasis in the annual program evaluation plan (paragraph 3.2.1B, TVA-SPP-18.013, “Safety Program Assessments”).

Evaluate Process (A31, D6, and T1) A.

The effectiveness of this process is assessed at all organization levels through periodic evaluations.

B.

Corporate Safety evaluates process effectiveness at least once every three years. (P9)

4.0

RECORDS

4.1

QA Records There are no QA records generated by this process.

9

Copies of any safety processes, checklists, procedures, photographs, etc., developed to respond to recommendations are included with the documentation provided.

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Non-QA Records The following non-QA records are generated by this process. A.

The manager in charge of the workplace and TVAP obtain witness statements and make photographs of the accident scene. This material becomes part of the investigation file maintained by Corporate Safety.

B.

The manager in charge of the workplace completes the checklist of initial actions (Appendix B). This checklist becomes part of the investigation file maintained by Corporate Safety.

C.

The DASHO and responsible EVP prepare a charter for the AIT. The approved charter becomes part of the investigation file maintained by Corporate Safety.

D.

In carrying out its responsibilities as defined in the charter, the AIT may collect physical evidence and obtain or generate documentation. Physical evidence is maintained by TVAP according to the statute of limitations for the state in which the accident occurs. Corporate Safety m ay retain this evide nce beyond that timeframe. Documentation becomes part of the investigation file maintained by Corporate Safety.

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E.

The manager in charge of the workplace prepares a form TVA 18119 and submits it to Corporate Safety. Data on this form is entered into WIIS which is maintained by Corporate Safety and is available on the “Safety Home Page.”

F.

The AIT prepares the “Accident Report.” This report becomes part of the investigation file maintained by Corporate Safety.

G.

The AIT prepares a form TVA 18120 and submits it to ESC. Data on this form is entered into WIIS and is available on the “Safety Home Page.”

H.

The AIT prepares the “Accident Analysis Report.” This report becomes part of the investigation file maintained by Corporate Safety.

I.

The AIT prepares material for use in briefing the responsible EVP, DASHO, and others. This material becomes part of the investigation file maintained by Corporate Safety.

J.

Opinions by AIT members, the DASHO, responsible EVP, and/or, as appropriate, the President and COO that differ from those in the “Accident Analysis Report” are documented. These differing opinions are attached to this report.

K.

The results of briefings provided are documented to include those attending, agreements reached, action items, etc. These briefing summaries become part of the investigation file maintained by Corporate Safety.

L.

The AIT documents “lessons learned” from the investigation and provides them to the DASHO. This material becomes part of the investigation file maintained by Corporate Safety.

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M.

TVAP prepares a summary of action taken to support the investigation. This summary becomes part of the investigation file maintained by Corporate Safety.

N.

Upon completion of all briefings, the DASHO distributes copies of the “Accident Analysis Report” to the Board and others. Copies of the transmittal correspondence become part of the investigation file maintained by Corporate Safety.

O.

The responsible EVP documents action taken/planned to address approved recommendations in the “Accident Analysis Report.” As part of executing this responsibility, these managers prepare timetables for addressing recommendations that remain open for more than 60 calendar days and provide status reports according to this plan. This material becomes part of the investigation file maintained by Corporate Safety.

P.

Corporate Safety may follow-up with the responsible organization to review status of implementation of corrective action. Follow-up reports become part of the investigation file maintained by Corporate Safety.

Q.

Issues that arise between Corporate Safety and the responsible organization regarding action taken or planned are resolved at the appropriate level of management. These resolutions are documented and become part of the investigation file maintained by Corporate Safety.

R.

Upon satisfactory completion of action on recommendations, Corporate Safety issues a closure memorandum. This memorandum becomes part of the investigation file maintained by Corporate Safety.

S.

The DASHO/Corporate Safety periodically analyzes results from serious accident investigations to identify trend and causal information for program improvement. These analyses become part of the investigation file maintained by Corporate Safety.

T.

Assessments of process effectiveness are conducted periodically by the DASHO/Corporate Safety, managers in charge of workplaces, safety managers of TVA organizations, EVPs, and others. Assessments conducted by the DASHO/Corporate Safety are maintained as permanent records. Other assessments are maintained by the performing organization/individual for two years.

DEFINITIONS Cause-and-effect diagram - a chart that shows the relationship between a quality characteristic (effect) and its contributing factors (causes). It is useful in organizing and displaying the various theories about what the root causes of the problem may be. Certified Safety and Health Committee - committee meeting the provisions of section 1-3 of Executive Order 12196 and of 29 CFR 1960, as listed and attested to by the TVA Board in writing to the Secretary of Labor. Corporate Safety - organization that provides direct support to the DASHO.

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Designated Agency Safety and Health Official (DASHO) - the individual who represents the interest and support of the TVA Board in the management and administration of the agency’s occupational safety and health program. The Executive Vice President, Human Resources, currently fills this position. Improvement activity summary - the vehicle used to document application of the six-step problem solving process. Labor representative - union official recognized by TVA as the representative of a bargaining unit. Local health and safety committee - a certified safety and health committee at a TVA plant, facility, or other local level. Manager in charge of the workplace - the most senior manager of a TVA plant or other facility, area, property, major work activity, etc. Occupational Safety and Health Administration (OSHA) - an organization within the U. S. Department of Labor that serves as TVA’s regulator for industrial health and safety matters. (www.osha.gov) Primary Sponsor - Manager, HS&WC. Safety managers of TVA organizations - Includes the COO, Customer Service and Marketing, and Facilities Management safety managers. Serious accident - A fatality or in-patient hospitalization of three or more TVA employees within 30 days of an accident. Other events which under slightly different circumstances would have resulted or may result in one of these outcomes may be defined as serious upon joint agreement between the DASHO and responsible EVP. Serious injury - a wound of the type such that there is a substantial probability that death or serious physical harm could result. EXAMPLE

OSHA has provided examples of injuries which constitute such harm including: •

Amputation (loss of all or part of a bodily appendage which includes loss of bone).

•

Concussion.

•

Crushing (internal, even though the skin surface may be intact).

•

Fracture (simple or compound).

•

Burns or scald (including electric and chemical).

•

Cuts, lacerations, or punctures involving significant bleeding and/or requiring suturing. Serious physical harm - a condition that could result in a part of the body being damaged so severely that it cannot be used or cannot be used very well. Six-step problem solving process - a procedure for addressing an undesirable result. The steps in this procedure include reason for improvement, problem definition, analysis, solutions, results, and process improvement

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TVA Safety Program Process Improvement Team - includes the safety managers of the line organizations and Corporate Safety. Work Injury/Illness System (WIIS) - TVA’s centralized data base for maintaining records of injuries and illnesses and reporting results to managers and other employees.

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APPENDIX A Page 1 of 2 PROCESS FLOW CHART AND CONTROL SYSTEM

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APPENDIX A Page 2 of 2 PROCESS FLOW CHART AND CONTROL SYSTEM

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APPENDIX B Page 1 of 1 CHECKLIST OF INITIAL ACTIONS FOR MANAGER IN CHARGE OF THE WORKPLACE WHERE A SERIOUS ACCIDENT OCCURS NOTE 5 Items are listed in the general order of preference. However, many of these activities can occur simultaneously. NOTE 6 Selected telephone numbers are provided in Appendix C. Attend to the needs of injured employee(s). Control hazardous energy source(s) or other condition(s). Secure the accident scene until released by the Accident Investigation Team (AIT) chairperson. Notify the TVA Police (TVAP) for assistance. Photograph the accident scene. Gather information listed below. Accident location: _______________________________________________________ Accident Time: __________________________________________________________ Name(s) of the individual(s) involved: ________________________________________ _______________________________________________________________________ Extent of injuries: ________________________________________________________ _______________________________________________________________________ Contact person (name and telephone number): _________________________________ _______________________________________________________________________ Brief description of the event:_______________________________________________ _______________________________________________________________________ _______________________________________________________________________ _______________________________________________________________________ Notify the responsible executive vice president, safety manager for the organization, and Corporate Safety as soon as possible. Provide a list of potential witnesses to TVAP. If TVAP is unavailable, obtain written statements from each witness about what happened. Witnesses will be interviewed by the AIT later.

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APPENDIX C Page 1 of 2 SERIOUS ACCIDENT NOTIFICATION CONTACT LIST 1.0

INTRODUCTION The following information summarizes responsibilities for notification in the event that a serious accident occurs.

2.0

SPECIFIC NOTIFICATION REQUIREMENTS

2.1

Manager in Charge of the Workplace Where the Accident Occurred Immediately Contacts the:

NOTE 7 If either of the individuals listed in paragraphs 2.1A or 2.1B is unavailable, do not delay in contacting the TVA Operator or the Program Manager, Corporate Safety.

2.2

A.

Responsible executive vice president of the organization where the accident occurred.

B.

Safety manager of the organization.

C.

TVA Operator at (865)-632-2101. Inform the operator that this call is to report a serious accident to the Program Manager, Corporate Safety. Alternate numbers for Corporate Safety are: 1.

Office: (865)-632-7753 or 7756 (during business hours).

2.

Cell phone: (865)-414-8819.

The Executive Vice President of the Organization Where the Serious Accident Occurred Contacts the: A.

TVA Board: (865)-632-2600.

B.

President and Chief Operating Officer: (865)-632-2366 or (423)-751-2352.

C.

Chief Nuclear Officer and Executive Vice President, TVA Nuclear: (423)-751-8682.

D.

Executive Vice President, Customer Service & Marketing: (615)-232-6011.

E.

Executive Vice President, River System Operations & Environment: (865)-632-3141.

F.

Executive Vice President, Transmission/Power Supply: (423)-751-6000.

G.

Executive Vice President, Fossil Power Group: (423)-751-2601.

H.

Executive Vice President, Administration: (865)-632-4352.

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APPENDIX C Page 2 of 2 SERIOUS ACCIDENT NOTIFICATION CONTACT LIST

2.3

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I.

Chief Financial Officer and Executive Vice President, Financial Services: (865)-632-4049.

J.

Executive Vice President, Communications and Government Relations: (865)-632-3199.

The Program Manager, Corporate Safety, Contacts the: A.

OSHA Area Office: (615)-781-5423 or (800)-321-OSHA.

B.

DASHO: (865)-632-6307.

C.

General Counsel: (865)-632-4131.

D.

Inspector General: (865)-632-4120 or (800)-323-3835.

E.

TVA Police: ((865)-632-3631 (24-hour line)F.

F.

Employee Assistance Program. Contact either: 1.

Program Manager Employee Wellness: (865)-632-4383.

2.

Horizon Health: (888)-482-2733.

G.

Vice President, External Communications: (865)-632-8001 or the “Media Duty Person” (865)-632-6000 (24-hour line).

H.

Vice President, Environmental Policy and Planning: (423)-751-3742 or 414-8489 (Cell).

I.

Appropriate labor representative(s).

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APPENDIX D Page 1 of 3 SAMPLE ACCIDENT INVESTIGATION TEAM CHARTER July 18, 19XX (Individual designated as AIT Chairperson) CHARTER FOR ACCIDENT INVESTIGATION TEAM INVOLVING A FATAL INJURY TO JOHN DOE AT ABC FOSSIL PLANT ON JULY 18, 19XX You have been selected to serve as chairperson of an accident investigation team (AIT) for the subject event in accordance with TVA-SPP-18.010, “Serious Accident Investigation.” Your selection represents our confidence in your ability to lead this important effort. This investigation is vital to help improve our safety performance. Its focus will be on preventing recurrence of similar events and not on placing blame on individuals or organizations. The Designated Agency Safety and Health Official’s (DASHO) representative on your team is available to assist you in carrying out your responsibilities and those of the AIT, as defined in TVA-SPP-18.010. In addition, the following individuals have been assigned to work under your direction for the duration of this task. 1.

AIT Members: (List the names of those individuals selected as members in accordance with paragraph 3.2.2, TVA-SPP-18.010; their respective “home” organizations; and team role.)

2.

AIT Advisors: (List the names, organizations, and roles of any advisors assigned to the AIT.) You are authorized to add additional advisors, as deemed necessary, to effectively complete this investigation.

As chairperson of this team, you are authorized to act on our behalf to complete a thorough and timely investigation. If you encounter difficulties or require guidance, please do not hesitate to contact us. Your team’s mission is to determine the facts and identify all root causes and contributing factors that led to this event and to develop those countermeasures necessary for preventing recurrence. We ask that the AIT explore all potential physical and programmatic causes and contributing factors. Your review to identify causes and contributing factors is expected to also include review and consideration of the adequacy of all safety and other processes that could have had a bearing on this accident. Your key deliverables are described in TVA-SPP-18.010. In summary, they include: 1.

The “Accident Report” (paragraphs 3.2.5A - C and Appendix E).

2.

A completed form TVA 18120 (paragraph 3.2.5D).

3.

The “Accident Analysis Report” (paragraph 3.2.5F - K and Appendix F).

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APPENDIX D Page 2 of 3 SAMPLE ACCIDENT INVESTIGATION TEAM CHARTER 4. Briefing material suitable for presentation to us and others (paragraph 3.2.6A). As noted above, the AIT members and advisors listed above (as well as any others you may identify) are available to assist you, as needed, until this investigation is complete. Please contact (name of appropriate manager in charge of the workplace) for any support or resources you need locally during the investigation. Notify us if additional resources are necessary. You should complete this investigation, including execution of deliverables and briefings, within the timeframes established by TVA-SPP-18.010. Contact us if you believe additional time is necessary to fulfill any of these commitments. Prior to completing this assignment, your team will identify “lessons learned” from participating in this investigation and provide them to the DASHO for process improvement. Your team will also collect all evidence, documentation, and other information obtained during the investigation and provide this material to the DASHO for retention. As chairperson you will manage this task according to this charter and TVA-SPP-18.010. Requests, directions, and/or inquiries that you may receive from others should be referred to us. While involved with this assignment, your time and that of team members and advisors will continue to be charged to your regular work account. Non-salary expenses incurred by the AIT will be charged to short code (12345AB). Your responsibilities as chairperson and those of the individuals assigned as team members and advisors are your top priority until this investigation is completed. In completing this assignment, we expect your full support and commitment. You have ours.

Designated Agency Safety And Health Official

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APPENDIX D Page 3 of 3 SAMPLE ACCIDENT INVESTIGATION TEAM CHARTER cc:

AIT advisors AIT members Director, TVA Police General Council Inspector General Manager in charge the workplace where the accident occurred Manager, Health, Safety, and Workers’ Compensation Other executive vice presidents President and Chief Operating Officer Program Manager, Corporate Safety Safety manager of the responsible TVA organization Safety managers of other TVA organizations Supervisors of AIT members and advisors Vice President, External Communications

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APPENDIX E Page 1 of 3 SAMPLE ACCIDENT REPORT SENSITIVE INFORMATION November 14, 2002 (Executive Vice President of the responsible organization) (DASHO) ACCIDENT REPORT FOR LOST-TIME INJURY TO JOHN DOE ON NOVEMBER 6, 2002 In accordance with TVA-SPP-18.010, “Serious Accident Investigation,” the “Accident Report” is attached for the injury to John Doe, Electrician, Transmission/Power Supply Group. This report was prepared by an Accident Investigation Team consisting of the following members. Name B. J. Mills W. Gary Hutcherson Billy J. Edwards H. O. Kemp Steve Hargrove Eddie Tramel Tommy Lucas Gene Mackey

Job Title and Organization Manager, Telecommunication Projects, ESP Manager, Substation Construction, ESP Manager, Contract Projects, ESP Manager, TPS Safety Production Supervisor, F&HP Customer Service Manager, CS&M Program Manager, Health and Safety Safety Specialist, TOM

Accident Investigation Team Chairperson SP 4H-C Attachment cc (Attachment): All other executive vice presidents General Counsel, ET 11A-K Manager, Health, Safety & Workers’ Compensation, ET 8A-K President and Chief Operating Officer, ET 12A-K Program Manager, H,S&WC, ET 8A-K Inspector General, ET 4C-K Chief Financial Officer, ET 12A-K Safety managers of TVA organizations

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APPENDIX E Page 2 of 3 SAMPLE ACCIDENT REPORT SENSITIVE INFORMATION

ACCIDENT REPORT LOST-TIME INJURY TO JOHN DOE On November 16, 2002

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APPENDIX E Page 3 of 3 SAMPLE ACCIDENT REPORT SENSITIVE INFORMATION Summary At approximately 2:00 a.m. (CST) on November 6, 2002, an accident occurred at TVA’s ABC 500 kV Substation. John Doe, Electrician, received an electric shock from induced voltage and was injured. Mr. Doe was taken to a Nashville hospital immediately following the accident where he remains in critical conditon. Background Prior to the accident, an electrician crew had installed lightning arrestors on the 161 kV bus for the Big Tree - ABC 161kV Transmission Line (Big Tree Line). The crew had begun work at approximately 12:30 a.m. (CST) after the line had been de-energized and grounded. All work for the installation had been essentially completed, and the crew was in the process of removing their tools and equipment from the job site in preparation for returning the line to service. The Accident At approximately 2:00 a.m. (CST), Mr. Doe intended to remove the equipment ground for the crane truck that had been used in the work from a structure in the yard. However, Mr. Doe inadvertently removed the ground-end clamp of a safety ground connected to the station ground mat. The other end of the safety ground was attached to the A-phase bus. This action created an arc between the clamp and mat, and Mr. Doe suffered an electrical shock from the induced voltage on the A-phase bus. The source of the induced voltage was a nearby energized 500 kV line. Mr. Doe fell with the ground-end clamp pinned under his body. Chuck Cates, Electrician Foreman, disengaged Mr. Doe from the voltage source. Mr. Doe was found to have no pulse. He was given cardiopulmonary resuscitation by Jim Ray, Electrician, and was revived. Emergency medical personnel were summoned to and arrived at the site. Mr. Doe was subsequently transported to XX Trauma Unit at the GWQ Hospital in Nashville where he remains in critical condition. Post Accident Events After Mr. Doe was transported from the ABC 500 kV Substation, the grounds were removed. The Big Tree Line was returned to service at approximately 2:30 a.m. (CST). An Accident Investigation Team was formed, and the scene preserved pending the team's arrival. Members of the team were on site at approximately 2:00 p.m. (CST) on November 6. The investigation is in progress.

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APPENDIX F Page 1 of 2 ACCIDENT ANALYSIS REPORT FORMAT SENSITIVE INFORMATION Copy x of y10 November 26, 2002 (Executive Vice President of the responsible organization) (DASHO) ACCIDENT ANALYSIS REPORT FOR LOST-TIME INJURY TO JOHN DOE ON NOVEMBER 6, 2002 Executive Summary (This section of the report provides a brief overview of what happened and highlights the AIT’s key findings, conclusions, and recommendations.) Accident Description (This section of the report describes the accident scenario and is extracted from the timeline developed by the AIT. The AIT should also refer to the “Accident Report” in developing this portion of the report.) Findings (This section of the report contains factual information discovered during and pertinent to the investigation, beyond that contained in the “Accident Description.” Facts are statements which are verifiable, objectively worded, and related to the accident. Some examples are laboratory results, regulatory requirements, prior investigation reports, and other documentation such as interview results. Findings provide the basis for drawing conclusions.) Conclusions (This section of the report contains the AIT’s opinions of why the accident occurred, i.e., the root causes. This information is summarized from the cause-and-effect diagram and root cause verification matrix prepared by the AIT. Recommendations are developed from conclusions.)

10

This report is a controlled document. No additional copies are to be made without prior written approval of the responsible EVP and DASHO.

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APPENDIX F Page 2 of 2 ACCIDENT ANALYSIS REPORT FORMAT SENSITIVE INFORMATION Copy x of y Corrective Actions (This section of the report contains the AIT’s recommendations to prevent recurrence of similar events. Recommendations suggest corrective actions to prevent recurrence. This information is extracted from the solutions matrix and action plan prepared by the AIT.) Attachments (This section of the report contains information that helps support AIT findings, conclusions, and recommendations. The improvement activity summary, work practices, safety procedures, organization’s safety manual, photographs, drawings, etc., are examples of material that may be included as attachments.)

(Name) Accident Investigation Team Chairperson (Address) cc:

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Manager, Health, Safety and Workers’ Compensation President and Chief Operating Officer (if the event occurs in the COO organization)

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Conduct Workplace Regulatory Compliance Inspections 1.

Purpose

1.1.

TVA-SPP-18.011, Conduct Workplace Regulatory Compliance Inspections establishes a process to detect, report, and correct unsafe and unhealthful conditions by conducting workplace regulatory compliance inspections, as required by the Occupational Safety and Health Administration (OSHA).

1.2.

TVA-SPP-18.011, Conduct Workplace Regulatory Compliance Inspections is attached.

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TITLE TVA STANDARD CONDUCT WORKPLACE REGULATORY COMPLIANCE PROGRAMS INSPECTIONS AND PROCESSES

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TVA-SPP-18.011 Rev. 0 Page 1 OF 18

Effective Date 08/06/2002

RESPONSIBLE PEER TEAM:

TVA Safety Program Process Improvement Team Organization

CONCURRENCES

Gary L. DePew Primary Sponsor

________ Date APPROVAL

John E. Long, Jr. Designated Agency Safety and Health Official

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________ Date

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REVISION LOG

Revision Number 0

Effective Date

Pages Affected

08/06/2002 All

Description of Revision Initial issue in this format. Supersedes “Implementing Criteria for Workplace Inspections,” Revision 01, January 27, 1999

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TABLE OF CONTENTS 1.0

PURPOSE................................................................................................................ III-105

2.0

SCOPE ..................................................................................................................... III-105

3.0

PROCESS ................................................................................................................ III-105

3.1 3.2

Roles and Responsibilities ........................................................................................ III-105 Instructions ................................................................................................................ III-108

4.0

RECORDS ............................................................................................................... III-112

4.1 4.2

QA Records................................................................................................................ III-112 Non-QA Records ..................................................................................................... III-112

5.0

DEFINITIONS ........................................................................................................ III-113

APPENDIX A - PROCESS CONTROL CHART AND CONTROL SYSTEM ........... III-114 APPENDIX B - FORM TVA 7109, TENNESSEE VALLEY AUTHORITY NOTICE OF UNSAFE OR UNHEALTHFUL WORKING CONDITIONS ...................................... III-118 APPENDIX C - ABATEMENT PLAN ............................................................................ III-119

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PURPOSE The objective of this process is to detect, report, and correct unsafe and unhealthful conditions by conducting workplace regulatory compliance inspections, as required by the Occupational Safety and Health Administration (OSHA).

2.0

SCOPE This process applies to all TVA employees.

3.0

PROCESS The quality indicator for this process is the number of injury/illness investigations where a regulatory violation resulting from inadequate inspection is identified as a contributing factor. (Q1) The following criteria are used to evaluate the efficiency and effectiveness of this process. In addition to Q1, process indicators shown in bold italic are tracked and results reported periodically to management.

3.1

A.

Establish inspection schedule prior to beginning the fiscal year. (P1)

B.

Issue notices for safety deficiencies within 15 workdays of an inspection. (P2)

C.

Issue notices for health hazards within 30 workdays of an inspection. (P3)

D.

Abate hazards by date on notice or abatement plan. (P4)

E.

Document corrective action and provide to inspector by abatement date on notice. (P5)

F.

Prepare and submit abatement plan to the inspector and DASHO for items not corrected within 30 calendar days. (P6)

G.

Close inspection. (P7)

H.

Analyze inspection findings annually for trends and root causes. (P8)

I.

Evaluate process effectiveness at least every three years. (P9)

Roles and Responsibilities Designated Agency Safety and Health Official (DASHO)/Corporate Safety A.

Provides advice on abatement of hazards, upon request.

B.

Assists with preparation of abatement plans, upon request.

C.

As necessary, participates in resolution of concerns on hazards identified, action taken/planned, etc.

D.

Provides for an automated corrective action system (CAS) for collecting and reporting inspection-related data.

E.

Reviews inspection and abatement data for trends, improvement opportunities, and adequacy.

F.

Provides periodic reports on results of these reviews.

G.

Approves and publishes this process.

H.

Tracks performance. III-105

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I.

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Evaluates process effectiveness.

Primary Sponsor Chairs the TVA Safety Program Process Improvement Team and recommends changes in this process to the DASHO. TVA Safety Program Process Improvement Team Receives, reviews, evaluates, and recommends action proposed by employees on suggested improvements to this process. Manager in Charge of the Workplace A.

Prepares annual inspection schedule.

B.

Designates inspector(s).

C.

Participates in inspection (workplace observation).

D.

Receives briefing on inspection results.

E.

As appropriate, identifies additional conditions during the briefing for consideration by the inspector.

F.

Reviews final inspection report.

G.

Distributes final report to employee representative(s) who participated in the inspection and local health and safety committee.

H.

Posts inspection results.

I.

Abates hazards identified in inspection report by established dates .

J.

Documents action taken to correct hazards identified and returns to inspector and DASHO/Corporate Safety for updating WCRIS.

K.

Prepares abatement plans for hazards requiring more than 30 days to correct.

L.

Submits abatement plans to inspector and DASHO/Corporate Safety for updating the CAS.

M.

For hazards addressed in abatement plans, advises local health and safety committee and employees exposed of interim protective measures and progress on plan implementation.

N.

As necessary, participates in resolution of concerns on hazards identified, action taken/planned, etc.

O.

Analyzes inspection results reports provided by the DASHO, internalizes results, and identifies replication opportunities.

P.

Periodically evaluates process effectiveness.

Inspector

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A.

Reviews prior reports/abatement plans, injury/illness records, planned work schedules, and other related information in preparation for inspection.

B.

Conducts inspection.

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C.

Briefs manager in charge of workplace and employee representative(s) on inspection results and provides draft copy of findings.

D.

Documents and classifies conditions identified during the inspection.

E.

Discusses any differences between draft and final reports with manager in charge of workplace prior to issue.

F.

Issues final report to manager in charge of workplace and enters into the CAS.

G.

Provides advice on abatement of hazards, upon request.

H.

Reviews corrective action for hazards identified and advises manager in charge of workplace on adequacy.

I.

As necessary, resolves concerns on hazards identified, action/taken planned, etc., with the manager in charge of the workplace or other appropriate organization level.

J.

Assists with preparation of abatement plans, upon request.

K.

Reviews abatement plans and advises manager in charge of workplace on adequacy.

L.

Tracks status of corrective actions until complete and closes inspection.

M.

Analyzes inspection results reports provided by the DASHO and suggests opportunities for replication.

N.

Periodically evaluates process effectiveness.

Employee Representative(s) A.

Participates in inspection (workplace observation).

B.

Participates in briefing on inspection results.

C.

As appropriate, identifies additional considerations during the briefing for consideration by the inspector.

D.

Reviews final inspection report.

E.

Assists with hazard abatement, upon request.

F.

Assists with preparation of abatement plans, upon request.

G.

Assists with resolution of concerns on hazards identified, action taken/planned, etc., upon request.

H.

Reviews action taken to correct identified hazards.

I.

Analyzes inspection results reports provided by the DASHO.

J.

Supports evaluation of process effectiveness.

Local Health and Safety Committee A.

Reviews final inspection report.

B.

Supports abatement of hazards, upon request.

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C.

Assists with development of abatement plans, upon request.

D.

Assists with resolution of concerns on hazards identified, action taken/planned, etc., upon request.

E.

Analyzes inspection results reports provided by the DASHO.

F.

Supports evaluation of process effectiveness.

Instructions

NOTE 1 Regulatory and other “drivers” for this process include the following. A.

Executive Order 12196, “Occupational Safety and Health Programs for Federal Employees” (requires heads of federal agencies to comply with basic program elements issued by the Secretary of Labor, including assuring that periodic inspections of all workplaces are performed by personnel with equipment and competence to recognize hazards and that prompt abatement of unsafe or unhealthful conditions occur).

B.

29 CFR 1960, “Basic Program Elements for Federal Employee Occupational Safety and Health Programs and Related Matters” (Subpart D establishes OSHA requirements for federal agencies on workplace inspection and abatement).

C.

TVA Principles and Practices, Health and Safety Practice 2, Safety (outlines the agency’s overall safety program, including provisions for inspections).

D.

TVA-SPP-18.0, “TVA Safety Program” (provides the agency’s program philosophy and a summary of the major safety processes, including inspections).

NOTE 2 Parenthesis (xx) in the paragraph headings that follow refer to symbols shown in the flow chart and control system for this process which are included as Appendix A. 3.2.1

Schedule Inspection (A1) TVA organizations schedule workplace regulatory compliance inspections annually. The schedule is completed by the beginning of the fiscal year. (P1)

3.2.2

Designate Inspector (A2) A.

Inspections are conducted by qualified inspectors as defined at 29CFR 1960.2(s).

EXAMPLE Qualified inspectors include safety specialists, industrial hygienists, fire protection engineers, etc., that are competent by virtue of education, training, and/or work experience to recognize and evaluate hazards of the working environment and to suggest general abatement methods.

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B.

The inspector is in charge of the inspection.

C.

The inspector is authorized to deny the right of accompaniment to any person whose participation interferes with conducting a fair and/or orderly inspection.

D.

The manager in charge of the workplace and an employee(s) [from the local health and safety committee, if possible] participate in the inspection.

E.

The inspector interviews a reasonable number of employees during the “walkaround” of the work area.

Review Health and Safety Information (A3) A.

The inspector reviews previous inspection reports/abatement plans, accident investigation reports/summaries, injury/illness records, employees' reports of unsafe and unhealthful conditions, industrial hygiene survey reports, minutes of local health and safety committee meetings, planned work schedules, operating and maintenance procedures, and other related safety information.

B.

Consideration is given to scheduling inspections so they coincide with higher exposure activities/operations, such as scheduled outages, energized work, and plant modernization.

Conduct Inspection (A4) A.

The inspector observes the workplace and job practices to identify hazards that could result in injury/illness. These conditions and practices observed are also compared against OSHA and consensus standards and organizational documentation for the group being inspected.

B.

Identification of hazards includes not only safety concerns, but also issues related to the health of employees. Health concerns are usually associated with hazardous agents such as noise, gas, vapor, mist, fumes, dust, heat, and ionizing or nonionizing radiation. Complete evaluation of the existence or extent of an identified health concern may require the services of a specialist, such as an industrial hygienist.

C.

If during the course of the inspection, a danger is identified that could reasonably be expected to cause death or serious physical harm immediately, the inspector will at once inform affected employees and the manager in charge of the workplace and/or property.

D.

The manager in charge of the workplace abates imminent danger conditions immediately. During abatement all employees not necessary for correcting this condition(s) will be removed from the work area. If assistance is required to abate the condition this manager promptly contacts appropriate individuals in TVA, up to and including the DASHO.

E.

The local health and safety committee will be informed of all relevant actions.

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3.2.6

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Provide Briefing on Inspection Findings (A5) A.

Upon completion of workplace observations, the inspector briefs the manager in charge of the workplace and the employee representative(s) on unsafe or unhealthful conditions identified during the inspection.

B.

During the briefing the manager in charge of the workplace and employee representative(s) may identify additional conditions.

C.

A draft of the inspection findings is provided to the manager in charge of the workplace at the briefing’s conclusion.

Document, Issue, and Review Inspection Results (A6 - A9) A.

Hazards identified during the inspection are documented and classified on form TVA 7109, TVA Notice of Unsafe or Unhealthful Working Conditions (Appendix B).

B.

Differences between findings in the final form TVA 7109 and those in the draft report previously provided are discussed with the manager in charge of the workplace prior to its release.

C.

A final form TVA 7109 for safety deficiencies is issued within 15 days (P2) after completion of the inspection.

D.

Notices of health hazards are issued within 30 days after completion of the inspection. (P3).

E.

If there are compelling reasons why notices can not be issued in the timeframes established in paragraphs 3.2.6C and 3.2.6D, the inspector notifies the manager in charge of the workplace, employee representative(s), and local health and safety committee.

F.

The final form TVA 7109 is sent to the manager in charge of the workplace and entered into the automated corrective action system (CAS).

G.

The manager in charge of the workplace provides copies of final form 7109 to the employee representative(s) who participated on the inspection and the local health and safety committee for review.

Post Inspection Results (A10) A.

The manager in charge of the workplace posts form TVA 7109 in a prominent place where it is readily observable to all employees.

B.

The notice remains posted for a period of three days or until the hazard is abated, whichever is longer.

Abate Hazards (A11, D1) The manager in charge of the workplace corrects hazards identified on form TVA 7109 in accordance with time frames set forth in the notice or the established abatement plan (paragraph 3.2.10). (P4)

3.2.9

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Track and Close Inspection Findings (A16 - A17, D3, A18 - A19)

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A.

Existing work control processes are used to track and close inspection findings.

B.

Ensuring that hazards are controlled until they can be abated must be an immediate concern of the manager in charge of the workplace. Action taken to mitigate an identified condition until abatement occurs must ensure that employees are not exposed to uncontrolled hazards.

C.

The manager in charge of the workplace assigns responsibility to track identified hazards until they are eliminated or controlled to an acceptable level.

D.

Corrective action for each item is described on the final form TVA 7109 in enough detail to ensure its understanding and returned to the inspector for review by the prescribed abatement date. (P5)

E.

The completed final form TVA 7109 is also entered into the CAS.

F.

The inspector advises the manager in charge of the workplace of the adequacy of corrective action taken.

G.

The inspector tracks action taken on deficiencies identified until all countermeasures are satisfactorily completed.

H.

Follow-up may include a site visit to review status of action taken.

I.

Any unresolved issues are elevated to the appropriate level of management for resolution.

J.

Within 10 workdays of all corrective action(s) being considered complete, the inspector sends a memorandum to those individuals who received the final form TVA 7109. This memorandum formally closes the inspection. (P7)

Prepare Abatement Plans (D1, A12 - A13, D2, A14 - A15) A.

If correction of a hazard takes longer than 30 calendar days after receipt of the final form TVA 7109, an abatement plan (Appendix C) is developed by the manager in charge of the workplace. As a minimum, an abatement plan includes: 1.

The identified hazard.

2.

Reason the hazard cannot be abated within 30 calendar days.

3.

Corrective action to be taken.

4.

Proposed abatement date.

5.

Interim measures to protect employees.

B.

The completed abatement plan is sent to the inspector for review by the original abatement date and to the DASHO for updating the CAS. (P6)

C.

The inspector advises the manager in charge of the workplace of the adequacy of the plan.

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3.2.11

3.2.12

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D.

Any unresolved issues or need for interpretation are referred by the inspector to the appropriate level of management for resolution in order to meet the proposed abatement date.

E.

The local health and safety committee and all employees subject to the hazard are advised of this action and of interim protective measures in effect. They are kept informed of subsequent progress on the abatement plan.

Review WRCIS Results and Provide Periodic Reports (A20, A21) A.

Data from the CAS and abatement plans are reviewed by the DASHO/Corporate Safety to identify trends and opportunities for improving TVA’s safety program.

B.

The DASHO/Corporate Safety periodically reports results of these reviews to management.

Analyze Inspection Findings (A22, A23, and T1) A.

Inspection findings are analyzed annually by management to determine weaknesses in the safety program. (P8)

B.

This analysis identifies reasons that this and other TVA safety management practices did not prevent these hazards from occurring. Inputs are requested from the inspector and others, as appropriate.

C.

Results of this analysis are internalized and replicated, as necessary, to prevent hazards from recurring.

D.

Results of this analysis are also used to determine areas of emphasis in the annual program evaluation plan (paragraph 3.2.1B, TVA-SPP-18.013, “Conduct Safety Program Assessments”).

Evaluate Process (A24, D4, and T1) A.

Process effectiveness will be assessed at all organization levels through periodic evaluations.

B.

The DASHO/Corporate Safety evaluates process effectiveness at least once every three years. (P9)

4.0

RECORDS

4.1

QA Records There are no QA records generated by this process.

4.2

Non-QA Records The following non-QA records are generated by this process.

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A.

Managers in charge of workplaces develop annual inspection schedules. These schedules (including transmittal memorandums) are maintained by these managers.

B.

Inspectors make notes on workplace observations, employee interviews, etc. This material is maintained by inspectors.

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C.

Inspectors prepare preliminary findings for discussion with managers in charge of workplaces at the conclusion of on-site visits. This material is maintained by inspectors.

D.

Inspectors provide a draft report to the manager in charge of the workplace. Inspectors maintain these reports.

E.

Inspectors provide a final evaluation report to the manager in charge of the workplace. Inspectors maintain these reports.

F.

The manager in charge of the workplace documents action taken/planned to address deficiencies identified during inspections on the final form TVA 7109. Completed final forms TVA 7109 are maintained by inspectors.

G.

Managers in charge of workplaces prepare abatement plans for hazards requiring more than 30 days to correct. Progress reports are provided consistent with dates in the abatement plan. Inspectors maintain these plans and associated progress reports.

H.

Inspectors may follow-up with organizations evaluated to review the status of implementation of corrective action. Follow-up reports are maintained by inspectors.

I.

Issues that arise between inspectors and organizations inspected regarding action taken or planned are resolved at the appropriate level of management. These resolutions are documented and maintained by inspectors.

J.

Upon satisfactory completion of action on hazards identified, inspectors issue a closure memorandum. Inspectors maintain these memorandums.

K.

An annual analysis of all inspections conducted during the year is prepared by the DASHO/Corporate Safety to identify trend and causal information for program improvement. These analyses are maintained by Corporate Safety.

L.

Assessments of process effectiveness are conducted periodically by the DASHO/Corporate Safety, inspectors, and managers in charge of TVA workplaces. Assessments conducted by the DASHO/Corporate Safety are maintained as permanent records. Other assessments are maintained by the performing organization/individual for two years.

DEFINITIONS Abatement Plan - developed when more than 30 calendar days are required to correct a hazard. Abatement plans describe the hazard identified, reason it cannot be abated within 30 days, corrective action to be taken, proposed abatement date, and interim measures to protect employees (for details see paragraph 3.2.10 of this process). Automated corrective action system (CAS) - centralized database used to capture safety and health deficiencies identified during inspections; track corrective action taken; prompt abatement plan development, as required; close inspections; and trend results (to be developed).

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Certified Safety and Health Committee - committee meeting the provisions of section 1-3 of Executive Order 12196 and of 29 CFR 1960, as listed and attested to by the TVA Board in writing to the Secretary of Labor. Consensus standards - requirements developed by (usually) nationally recognized standard setting groups, such as the American National Standards Institute or National Fire Protection Association, that reflect consensus on a particular topic among groups of qualified subject matter experts. Corporate Safety - a work group within Health, Safety and Workers’ Compensation (HS&WC) that serves as the DASHO’s staff. Designated Agency Safety and Health Official (DASHO) - the individual who represents the interest and support of the TVA Board in the management and administration of the agency’s occupational safety and health program. The Executive Vice President, Human Resources, currently fills this position. Imminent danger - any conditions or practices in any workplace which are such that a danger exists which could reasonably be expected to cause death or serious physical harm immediately or before the imminence of such danger can be eliminated through normal procedures. Inspector - individual qualified to recognize and evaluate hazards of the work environment and to suggest general abatement procedures. Safety and health specialists, as defined in 29 CFR 1960.2(s), with experience and/or up-to-date training in occupational safety and health hazard recognition and evaluation are considered as meeting the qualifications of safety and health inspectors. For those working environments where there are less complex hazards, such safety and health specializations as cited above may not be required, but inspectors in such environments shall have sufficient documented training and/or experience in the safety and health hazards of the workplace involved to recognize and evaluate those particular hazards and to suggest general abatement procedures. All inspection personnel must be provided the equipment necessary to conduct a thorough inspection of the workplace involved. Local health and safety committee - a certified safety and health committee at a TVA plant, facility, or other local level. Manager in charge of the workplace - the most senior manager of a TVA plant, facility, area, property, major work activity, etc. Occupational Safety and Health Administration (OSHA) - an organization within the U. S. Department of Labor that serves as TVA’s regulator for industrial health and safety matters. (www.osha.gov) Office of Personnel Management (OPM) - an organization that regulates various federal agency human resources systems. (www.opm.gov) Organizational documentation - documents published by agency organizations to clarify requirements in TVA Standard Programs and Processes (SPP) and/or address needs unique to a particular work group. References and links to these requirements are included in the appropriate TVA SPP.

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OSHA standards - typically include 29 CFR 1910, “Occupational Safety and Health Standards;” 29CFR 1926, “Safety and Health Regulations for Construction;” 29 CFR 1960; and other requirements published by OSHA that apply to TVA operations. Primary Sponsor - Manager, HS&WC. Safety and health specialist - individual meeting OPM standards for occupations, which include but are not limited to: A.

Safety and Occupational Health Manager/Specialist, GS-018.

B.

Safety Engineer, GS-803.

C.

Fire prevention Engineer, GS-804.

D.

Industrial Hygienist, GS-690.

E.

Fire protection and Prevention Specialist/Marshal, GS-081.

F.

Health Physicist, GS-1306.

G.

Occupational Medicine Physician, GS-602.

H.

Occupational Health Nurse, GS-610.

I.

Safety Technician, GS-019.

J.

Physical Science Technician, GS-1311.

K.

Environmental Health Technician, GS-699.

L.

Air Safety Specialist, GS-1825.

M.

Chemist, GS-1320.

N.

Health Technician, GS-645.

O.

Highway Safety Manager, GS-2125.

P.

Equally qualified military, agency, or non-government personnel. The DASHO is responsible for determination and certification of equally qualified personnel.

TVA Safety Management Practices - TVA SPPs, such as this document, that define management’s expectations and guide their execution and evaluation, and improvement to ensure that the agency maintains an effective safety program. TVA Safety Program Process Improvement Team - includes the safety managers of TVA organizations and Corporate Safety.

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APPENDIX A Page 1 of 2 PROCESS CONTROL CHART AND CONTROL SYSTEM

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APPENDIX A Page 2 of 2 PROCESS CONTROL CHART AND CONTROL SYSTEM

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APPENDIX B Page 1 of 1 FORM TVA 7109, TENNESSEE VALLEY AUTHORITY NOTICE OF UNSAFE OR UNHEALTHFUL WORKING CONDITIONS

TENNESSEE VALLEY AUTHORITY NOTICE OF UNSAFE OR UNHEALTHFUL WORKING CONDITIONS Inspection Number: Plant/Site: Item No.

Date of Inspection:

Unsafe/Unhealthful Condition

Location

Inspector: Standard Violated

Hazard Classification*

Page Abatement Date

Date Completed

of Action Taken

_____________________________ Inspector’s Signature *NOTE:

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All hazards will be classified into one of the following categories as defined. Imminent Danger (ID) - Condition could reasonably be expected to cause death or serious physical harm immediately. Serious (S) - Condition where there is a substantial probability that death or serious physical harm could result. Nonserious (NS) - Condition that is not likely to cause death or serious physical harm.

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APPENDIX C Page 1 of 1 ABATEMENT PLAN

Hazard Abatement Plan Abatement Plan Issue Date: Plant/Site:

Date of Inspection:

Inspector:

Item No.

Hazard:

Reason Hazard Cannot be Corrected Within 30 Days:

Proposed Corrective Action and Abatement Date: Interim Measures to Protect Employees:

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TVA-SPP-18.012 Report, Investigate, and Classify Injuries and Illnesses 1.

Purpose

1.1.

TVA-SPP-18.012, Report, Investigate and Classify Injuries and Illnesses establishes a process to report, investigate and classify workplace injuries and illnesses.

1.2.

TVA-SPP-18.012, Report, Investigate and Classify Injuries and Illnesses is attached.

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TITLE TVA STANDARD REPORT, INVESTIGATE, AND CLASSIFY INJURIES AND PROGRAMS ILLNESSES AND PROCESSES

TVA-SPP-18.012 Rev. 2 04/29/05 Page 1 OF 29

Effective Date 05/29/05

RESPONSIBLE PEER TEAM:

Safety Process Ownership Team Organization

CONCURRENCES

Phillip L. Reynolds VP, COO Operations Support

04/29/05 Date

APPROVAL John E. Long, Jr. Designated Agency Safety and Health Official

04/29/05 Date

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REVISION LOG

Revision Number

Effective Date

0

08/06/200

All

Initial issue in this format. Supersedes “Implementing Criteria for Report and Investigate Injuries and Illnesses,” Revision 02, June 1, 1997.

1

12/05/04

All

Paragraph 3.2.6 B. revised to add a report on supervisor accident experience to the list of reports available from Corporate Safety. Paragraph 3.2.6 F. has been added to require TVA management to review supervisor accident experience for the purpose of determining causes for unfavorable trends taking corrective action as required.Form TVA 18120 in Appendix F and G was modified to require the “Name of Responsible Supervisor” and “Supervisor’s SSN” to be provided when completing the form. This information was previously optional; however, it is now required to allow the additional report on supervisor accident experience to be processed.

2

05/29/05

All

General revision to implement OSHA recordkeeping requirements for federal agencies.

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Pages Affected

Description of Revision

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TABLE OF CONTENTS 1.0

PURPOSE................................................................................................................ III-124

2.0

SCOPE ..................................................................................................................... III-124

3.0

ROLES AND RESPONSIBILITIES..................................................................... III-124

3.1 3.2

Training ..................................................................................................................... III-126 Instructions................................................................................................................ III-126

4.0

DEFINITIONS ........................................................................................................ III-139

APPENDIX A - EXCEPTIONS TO RECORDING INJURIES AND ILLNESSES.... III-141 APPENDIX B - OSHA 300, LOG OF WORK-RELATED INJURIES AND ILLNESSES ............................................................................................ III-142 APPENDIX C - FORM TVA 18120, TVA INJURY/ILLNESS INVESTIGATION REPORT ........................................................................................................... III-143 APPENDIX D - NOTICE OF INJURY - OSHA 301 FORM TVA 17719 .................... III-151 APPENDIX E - OSHA 300A, LOG OF WORK-RELATED INJURIES AND ILLNESSES ............................................................................................. III-152

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1.0

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REPORT, INVESTIGATE, AND CLASSIFY INJURIES AND ILLNESSES PURPOSE The objectives of this process are to:

2.0

A.

Establish a standardized method for reporting, investigating, and classifying work-related injuries and illnesses that meets the requirements in OSHA 29 Code of Federal Regulations 1904.

B.

Aid in establishing root causes for injuries and illnesses and in identifying and verifying that corrective actions are taken by management to improve TVA’s safety performance.

SCOPE This process applies to all TVA employees and contract augmented employees under TVA’s direct supervision.

3.0

Roles and Responsibilities Designated Agency Safety and Health Official (DASHO)/Corporate Safety A.

Ensures that the new OSHA 29 CFR 1904 recordkeeping requirements are maintained on a calendar year basis.

B.

Assists with classification of work-related injuries and illnesses based on the requirements of 29 CFR 1904 upon request.

C.

Assists with investigation of work-related injuries and illnesses and near miss incidents upon request.

D.

Reviews required recordkeeping forms for adequacy.

E.

As necessary, resolves issues associated with adequacy of required recordkeeping forms with the appropriate level of management.

F.

As owner of the Work Injury Illness System (WIIS) reconciles data in WIIS with that provided by the Office of Workers’ Compensation Programs (OWCP) quarterly.

G.

Analyzes the data in WIIS and produces monthly and ad hoc reports for management on performance and causes and trends associated with TVA’s and augmented employees’ injuries and illnesses.

H.

Validates that the appropriate TVA reporting organization prepares, signs, and posts the OSHA Form 300A, “Summary of Work Related Injuries and Illnesses,” as required. The OSHA Form 300A (Appendix E) must be posted from February 1st until April 30.

I.

Assesses process effectiveness at least every three years.

Manager in Charge of the Workplace

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A.

Ensures prompt medical treatment is provided for injured employees.

B.

Reports and carries out other assigned responsibilities for serious accidents (paragraph 3.2.1B, TVA-SPP-18.010, “Serious Accident Investigation”).

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C.

All work-related injuries that must be recorded on the OSHA Form 300, “Log of Work-Related Injuries and Illnesses” shall be reported on the TVA Form 17719, “Notice of Injury / Illnesses” (NOI) –OSHA 301, Appendix D. This is a TVA equivalent to the OSHA Form 301. All sections on the TVA Form 17719 shall be completed. When the case is recorded on the Log, the case number assigned on the Log shall be added to the TVA Form 17719. The TVA Form 17719 shall be completed and submitted within 48 hours to TVA Safety and TVA Information Services. Each establishment shall maintain the NOI on file for five years.

D.

Classifies work-related injuries and illnesses based on the requirements of OSHA 29 CFR 1904, “Recording and Reporting Occupational Injuries and Illnesses. This OSHA regulation became effective on January 1, 2005. OSHA has granted federal employers one year (January 1, 2006) to come into full compliance with these requirements.

E.

Investigates work-related injuries and illnesses (Initiate investigation within 24 hours of event) utilizing form TVA 18120 “TVA Injury/Illness Investigation Report,” and when required the organizations approved corrective action program.

F.

Based on the requirements of OSHA 29 CFR 1904, ensure each recordable injury or illness is entered on the OSHA 300 log within seven (7) days of receiving information that a recordable injury or illness has occurred. Submits OSHA 300 log to Muscle Shoals IS group within 3 calendar days after the end of the month.

G.

Each TVA business unit must prepare, si gn, and post at the work location the OSHA Form 300A, “Summary of Work-Related Injuries and Illnesses,” for their organization. The OSHA Form 300A must be posted from February 1st until April 30th each year.

H.

As necessary, participates in resolution of issues associated with adequacy of forms with the DASHO/Corporate Safety and/or the appropriate level of management.

I.

Identifies countermeasures to prevent work-related injuries and illnesses, takes corrective action, and monitors effectiveness of results achieved.

J.

Standardizes/replicates results and elevates, as appropriate.

K.

Periodically assesses process effectiveness.

TVA Safety Consultants / Representatives A.

Provides assistance to line management in reporting, investigation and classification of injuries and illnesses in conformance with the requirements of this procedure.

Employees A.

Promptly report work-related injuries or illnesses to their supervisors.

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B.

Participate in the investigation of work-related injuries or illnesses, as requested.

C.

Participate in the implementation of corrective action to prevent work-related injuries or illnesses.

D.

Participate in standardization/replication of results.

Information Services (IS) A.

Operates and maintains WIIS.

B.

Reviews and enters data into WIIS.

C.

Produces monthly reports from WIIS data and post on the “TVA Safety Resource Network.”

D.

Reconciles WIIS data quarterly with that provided by OWCP on behalf of the DASHO/Corporate Safety.

E.

Periodically evaluates process effectiveness.

Occupational Health and Workers Compensation

3.1

A.

Maintains workers’ compensation data for TVA.

B.

Periodically evaluates process effectiveness.

Training Due to significant changes in OSHA recordkeeping that have gone into effect for Federal Agencies such as TVA, training course ATIS 00059191, “New OSHA Recordkeeping Requirements for Recording, Reporting, and Classifying Injuries and Illnesses,” is required for all safety consultants/representatives, nurses, other personnel who are responsible for completion of forms required by this process, and IS employees who enter and roll-up injury and illnesses data. We encourage senior managers in the workplace to participate in this training since they must sign the injury/illness summaries indicating accuracy.

3.2

Instructions

NOTE 1 Regulatory and other “drivers” for this process include the following.

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A.

Occupational Safety and Health Act of 1970 (Section 19 requires heads of federal agencies to keep adequate records of all occupational accidents and illnesses for proper evaluation and necessary corrective action).

B.

Executive Order 12196, “Occupational Safety and Health Programs for Federal Employees” (requires heads of federal agencies to comply with basic program elements issued by the Secretary of Labor, including operation of an occupational safety and health management information system which shall include the maintenance of such records as the Secretary may require).

C.

29 CFR 1904, “Recording and Reporting Occupational Injuries and Illnesses” (establishes the Occupational Safety and Health Administration [OSHA] requirement for injury/illness reporting and investigation).

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D.

TVA Principles and Practices, “Health and Safety Practice 2, Safety” (outlines the agency’s overall safety program, including provisions for accident reporting and investigation).

E.

TVA-SPP-18.0, “TVA Safety Program” (describes key features of TVA’s safety program, including requirements for reporting and investigating workrelated injuries and illnesses).

F.

TVA-SPP-18.010, “Serious Accident Investigation” (establishes TVA’s process for investigating serious accidents).

G.

TVA Workers’ Compensation Program requirements (provide guidance on claims management).

Define Incidents A.

This process addresses reporting, investigating and classifying of occupational injuries and illnesses and near-miss incidents that occur to TVA and augmented employees under TVA supervision.

B.

You must consider an injury or illness to be work-related if an event or exposure in the work environment either caused or contributed to the resulting condition or significantly aggravated a pre-existing injury or illness. Workrelatedness is presumed for injuries and illnesses resulting from events or exposures occurring in the work environment, unless an exception in 29 CFR 1904.5(b)(2) specifically applies (See Appendix A).

C.

OSHA defines the work environment as "the establishment and other locations where one or more employees are working or are present as a condition of their employment. The work environment includes not only physical locations, but also the equipment or materials used by the employee during the course of his or her work."

D.

You must consider an injury or illness to be a "new case" if:

E.

•

The employee has not previously experienced a recorded injury or illness of the same type that affects the same part of the body, or

•

The employee previously experienced a recorded injury or illness of the same type that affected the same part of the body but had recovered completely (all signs and symptoms had disappeared) from the previous injury or illness and an event or exposure in the work environment caused the signs or symptoms to reappear.

You must consider an injury or illness to meet the general recording criteria, and therefore to be recordable, if it results in any of the following: death, days away from work, restricted work or transfer to another job, medical treatment beyond first aid, or loss of consciousness. You must also consider a case to meet the general recording criteria if it involves a significant injury or illness diagnosed by a physician or other licensed health care professional, even if it

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does not result in death, days away from work, restricted work or job transfer, medical treatment beyond first aid, or loss of consciousness. F.

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Occupational injuries and illnesses vary in outcome from fatal (most severe) to first aid (least severe). The following define each outcome and their recordability. 1.

A fatal work-related injury or illness results in death to an employee regardless of the time between the event and death. You must record an injury or illness that results in death by entering a check mark on the OSHA 300 Log in the space for cases resulting in death. You must also report any work-related fatality or inpatient hospitalization of three or more employees to OSHA within eight (8) hours, as required by 29 CFR 1904.39.

2.

Days Away From Work (Lost-time) When an injury or illness involves one or more days away from work, you must record the injury or illness on the OSHA 300 Log with a check mark in the space for cases involving days away and an entry of the number of calendar days away from work in the number of days column. If the employee is out for an extended period of time, you must enter an estimate of the days that the employee will be away, and update the day count when the actual number of days is known. Determination of the amount of time associated with a lost-time injury or illness must be consistent with the following. •

Begin counting days away on the day after the injury occurred or the illness began.

•

You must record these injuries and illnesses on the OSHA 300 Log using the check box for cases with days away from work and enter the number of calendar days away recommended by the physician or other licensed health care professional. If a physician or other licensed health care professional recommends days away, you should encourage your employee to follow that recommendation. However, the days away must be recorded whether the injured or ill employee follows the physician or licensed health care professional's recommendation or not. If you receive recommendations from two or more physicians or other licensed health care professionals, you may make a decision as to which recommendation is the most authoritative, and record the case based upon that recommendation.

•

End the count of days away from work on the date the physician or other licensed health care professional recommends that the employee returns to work.

•

Count the number of calendar days the employee was unable to work as a result of the injury or illness, regardless of whether or not the employee was scheduled to work on those day(s). Weekend days, holidays, vacation days or other days off are included in the total

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number of days recorded if the employee would not have been able to work on those days because of a work-related injury or illness. •

If a worker is injured or becomes ill on a Friday and reports to work on a Monday, and was not scheduled to work on the weekend, record this case only if you receive information from a physician or other licensed health care professional indicating that the employee should not have worked, or should have performed only restricted work, during the weekend. If so, you must record the injury or illness as a case with days away from work or restricted work, and enter the day counts, as appropriate.

•

If a worker is injured or becomes ill on the day before scheduled time off such as a holiday, a planned vacation, or a temporary plant closing, record a case of this type only if you receive information from a physician or other licensed health care professional indicating that the employee should not have worked, or should have performed only restricted work, during the scheduled time off. If so, you must record the injury or illness as a case with days away from work or restricted work, and enter the day counts, as appropriate.

•

The number of days away from work that must be counted are as follows: You may "cap" the total days away at 180 calendar days. You are not required to keep track of the number of calendar days away from work if the injury or illness resulted in more than 180 calendar days away from work and/or days of job transfer or restriction. In such a case, entering 180 in the total days away column will be considered adequate.

•

Counting days if an employee who is away from work because of an injury or illness retires or leaves my company. If the employee leaves your company for some reason unrelated to the injury or illness, such as retirement, a plant closing, or to take another job, you may stop counting days away from work or days of restriction/job transfer. If the employee leaves your company because of the injury or illness, you must estimate the total number of days away or days of restriction/job transfer and enter the day count on the 300 Log.

•

Cases occurring in one year but results in days away during the next calendar year. Only record the injury or illness once. You must enter the number of calendar days away for the injury or illness on the OSHA 300 Log for the year in which the injury or illness occurred. If the employee is still away from work because of the injury or illness when you prepare the annual summary, estimate the total number of calendar days you expect the employee to be away from work, use this number to calculate the total for the annual summary, and then update the initial log entry later when the day count is known or reaches the 180-day cap. III-129

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Restricted work or transfer to another job. How do I record a workrelated injury or illness that results in restricted work or job transfer? When an injury or illness involves restricted work or job transfer but does not involve death or days away from work, you must record the injury or illness on the OSHA 300 Log by placing a check mark in the space for job transfer or restriction and an entry of the number of restricted or transferred days in the restricted workdays column. How do I decide if the injury or illness resulted in restricted work? Restricted work occurs when, as the result of a work-related injury or illness: •

You keep the employee from performing one or more of the routine functions of his or her job, or from working the full workday that he or she would otherwise have been scheduled to work; or

•

A physician or other licensed health care professional recommends that the employee not perform one or more of the routine functions of his or her job, or not work the full workday that he or she would otherwise have been scheduled to work.

•

What is meant by "routine functions"? For recordkeeping purposes, an employee's routine functions are those work activities the employee regularly performs at least once per week.

•

Do I have to record restricted work or job transfer if it applies only to the day on which the injury occurred or the illness began? No, you do not have to record restricted work or job transfers if you, or the physician or other licensed health care professional, impose the restriction or transfer only for the day on which the injury occurred or the illness began.

•

If you or a physician or other licensed health care professional recommends a work restriction, is the injury or illness automatically recordable as a "restricted work" case? No, a recommended work restriction is recordable only if it affects one or more of the employee's routine job functions. To determine whether this is the case, you must evaluate the restriction in light of the routine functions of the injured or ill employee's job. If the restriction from you or the physician or other licensed health care professional keeps the employee from performing one or more of his or her routine job functions, or from working the full workday the injured or ill employee would otherwise have worked, the employee's work has been restricted and you must record the case.

•

How do I record a case where the worker works only for a partial work shift because of a work-related injury or illness? A partial day of work is recorded as a day of job transfer or restriction for

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recordkeeping purposes, except for the day on which the injury occurred or the illness began. •

If the injured or ill worker produces fewer goods or services than he or she would have produced prior to the injury or illness but otherwise performs all of the routine functions of his or her work, is the case considered a restricted work case? No, the case is considered restricted work only if the worker does not perform all of the routine functions of his or her job or does not work the full shift that he or she would otherwise have worked.

•

How do I handle vague restrictions from a physician or other licensed health care professional, such as that the employee engage only in "light duty" or "take it easy for a week"? If you are not clear about the physician or other licensed health care professional's recommendation, you may ask that person whether the employee can do all of his or her routine job functions and work all of his or her normally assigned work shift. If the answer to both of these questions is "Yes," then the case does not involve a work restriction and does not have to be recorded as such. If the answer to one or both of these questions is "No," the case involves restricted work and must be recorded as a restricted work case. If you are unable to obtain this additional information from the physician or other licensed health care professional who recommended the restriction, record the injury or illness as a case involving restricted work.

•

What do I do if a physician or other licensed health care professional recommends a job restriction meeting OSHA's definition, but the employee does all of his or her routine job functions anyway? You must record the injury or illness on the OSHA 300 Log as a restricted work case. If a physician or other licensed health care professional recommends a job restriction, you should ensure that the employee complies with that restriction. If you receive recommendations from two or more physicians or other licensed health care professionals, you may make a decision as to which recommendation is the most authoritative, and record the case based upon that recommendation.

•

How do I decide if an injury or illness involved a transfer to another job? If you assign an injured or ill employee to a job other than his or her regular job for part of the day, the case involves transfer to another job. Note: This does not include the day on which the injury or illness occurred.

•

Are transfers to another job recorded in the same way as restricted work cases? Yes, both job transfer and restricted work cases are recorded in the same box on the OSHA 300 Log. For example, if you assign, or a physician or other licensed health care professional III-131

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recommends that you assign, an injured or ill worker to his or her routine job duties for part of the day and to another job for the rest of the day, the injury or illness involves a job transfer. You must record an injury or illness that involves a job transfer by placing a check in the box for job transfer. •

4.

How do I count days of job transfer or restriction? You count days of job transfer or restriction in the same way you count days away from work, using 29 CFR 1904.7(b)(3)(i) to (viii). The only difference is that, if you permanently assign the injured or ill employee to a job that has been modified or permanently changed in a manner that eliminates the routine functions the employee was restricted from performing, you may stop the day count when the modification or change is made permanent. You must count at least one day of restricted work or job transfer for such cases.

Medical treatment beyond first aid. How do I record an injury or illness that involves medical treatment beyond first aid? If a workrelated injury or illness results in medical treatment beyond first aid, you must record it on the OSHA 300 Log. If the injury or illness did not involve death, one or more days away from work, one or more days of restricted work, or one or more days of job transfer, you enter a check mark in the box for cases where the employee received medical treatment but remained at work and was not transferred or restricted. •

What is the definition of medical treatment? "Medical treatment" means the management and care of a patient to combat disease or disorder. For the purposes of Part 1904, medical treatment does not include: o Visits to a physician or other licensed health care professional solely for observation or counseling; o The conduct of diagnostic procedures, such as x-rays and blood tests, including the administration of prescription medications used solely for diagnostic purposes (e.g., eye drops to dilate pupils); or o "First aid" as defined in paragraph 5 below.

5.

First Aid. First aid means the following: •

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Using a non-prescription medication at nonprescription strength (for medications available in both prescription and non-prescription form, a recommendation by a physician or other licensed health care professional to use a non-prescription medication at prescription strength is considered medical treatment for recordkeeping purposes);

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•

Administering tetanus immunizations (other immunizations, such as Hepatitis B vaccine or rabies vaccine, are considered medical treatment);

•

Cleaning, flushing or soaking wounds on the surface of the skin;

•

Using wound coverings such as bandages, Band-Aids™, gauze pads, etc.; or using butterfly bandages or Steri-Strips™ (other wound closing devices such as sutures, staples, etc., are considered medical treatment);

•

Using hot or cold therapy;

•

Using any non-rigid means of support, such as elastic bandages, wraps, nonrigid back belts, etc. (devices with rigid stays or other systems designed to immobilize parts of the body are considered medical treatment for recordkeeping purposes);

•

Using temporary immobilization devices while transporting an accident victim (e.g., splints, slings, neck collars, back boards, etc.).

•

Drilling of a fingernail or toenail to relieve pressure, or draining fluid from a blister;

•

Using eye patches;

•

Removing foreign bodies from the eye using only irrigation or a cotton swab;

•

Removing splinters or foreign material from areas other than the eye by irrigation, tweezers, cotton swabs or other simple means;

•

Using finger guards;

•

Using massages (physical therapy or chiropractic treatment are considered medical treatment for recordkeeping purposes); or

•

Drinking fluids for relief of heat stress.

5.1

Are any other procedures included in first aid? No, this is a complete list of all treatments considered first aid for Part 1904 purposes.

5.2

Does the professional status of the person providing the treatment have any effect on what is considered first aid or medical treatment? No, OSHA considers the treatments listed in 29 CFR 1904.7(b)(5)(ii) to be first aid regardless of the professional status of the person providing the treatment. Even when these treatments are provided by a physician or other licensed health care professional, they are considered first aid for the purposes of Part 1904. Similarly, OSHA considers treatment beyond first aid to be medical treatment even when it is provided by someone other than a physician or other licensed health care professional.

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5.3

What if a physician or other licensed health care professional recommends medical treatment but the employee does not follow the recommendation? If a physician or other licensed health care professional recommends medical treatment, you should encourage the injured or ill employee to follow that recommendation. However, you must record the case even if the injured or ill employee does not follow the physician or other licensed health care professional's recommendation.

6.0

Loss of consciousness. Is every work-related injury or illness case involving a loss of consciousness recordable? Yes, you must record a work-related injury or illness if the worker becomes unconscious, regardless of the length of time the employee remains unconscious.

7.0

A significant injury or illness diagnosed by a physician or other licensed health care professional. What is a "significant" diagnosed injury or illness that is recordable under the general criteria even if it does not result in death, days away from work, restricted work or job transfer, medical treatment beyond first aid, or loss of consciousness? Work-related cases involving cancer, chronic irreversible disease, a fractured or cracked bone, or a punctured eardrum must always be recorded under the general criteria at the time of diagnosis by a physician or other licensed health care professional. OSHA believes that most significant injuries and illnesses will result in one of the criteria listed in 29 CFR 1904.7(a): death, days away from work, restricted work or job transfer, medical treatment beyond first aid, or loss of consciousness. However, there are some significant injuries, such as a punctured eardrum or a fractured toe or rib, for which neither medical treatment nor work restrictions may be recommended. In addition, there are some significant progressive diseases, such as byssinosis, silicosis, and some types of cancer, for which medical treatment or work restrictions may not be recommended at the time of diagnosis but are likely to be recommended as the disease progresses. OSHA believes that cancer, chronic irreversible diseases, fractured or cracked bones, and punctured eardrums are generally considered significant injuries and illnesses, and must be recorded at the initial diagnosis even if medical treatment or work restrictions are not recommended, or are postponed, in a particular case.

8.

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An other compensable incident (OCI) includes work-related injuries or illnesses that result in the creation of a case by OWCP and that do not otherwise meet the criteria for classification in D1 through D7 above.. All OCI events must be entered on the OSHA form 300 without checking a classification on the form. The designation of OCI must be entered in column “F.”

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9.

A near-miss incident is an occurrence which, given slightly different circumstances, could have resulted in an injury or illness.

10.

Needle Stick Injuries: You must record all work-related needle stick injuries and cuts from sharp objects that are contaminated with another person's blood or other potentially infectious material (as defined by 29 CFR 1910.1030). You must enter the case on the OSHA 300 Log as an injury. To protect the employee's privacy, you may not enter the employee's name on the OSHA 300 Log (see the requirements for privacy cases in paragraphs 1904.29(b)(6) through 1904.29(b)(9)).

11.

Medical Removal: If an employee is medically removed under the medical surveillance requirements of an OSHA standard, you must record the case on the OSHA 300 Log. See 29 CFR 1904.9 (b) for specific requirements.

12.

Hearing Loss: If an employee's hearing test (audiogram) reveals that the employee has experienced a work-related Standard Threshold Shift (STS) in hearing in one or both ears, and the employee's total hearing level is 25 decibels (dB) or more above audiometric zero (averaged at 2000, 3000, and 4000 Hz) in the same ear(s) as the STS, you must record the case on the OSHA 300 Log. See 29 CFR 1904.10(b) for specific requirements. This requirement excludes TVA retirees and others that have left the employment of TVA under normal circumstances.

13.

Work Related Tuberculosis: If any of your employees has been occupationally exposed to anyone with a known case of active tuberculosis (TB), and that employee subsequently develops a tuberculosis infection, as evidenced by a positive skin test or diagnosis by a physician or other licensed health care professional, you must record the case on the OSHA 300 Log by checking the "respiratory condition" column. See 29 CF R 1904.11(b) for specific requirements. Note: Privacy cases shall be entered on the OSHA 300 log without affected employee name (intimate body part/reproductive system, sexual assault, mental illness, HIV/Hepatitis/TB, needle stick, other illnesses). Employees and their representatives have the right of access to the OSHA and TVA injury and illness records. The specific requirements are in 29 CFR 1904.35.

3.2.2

Report Incidents A.

An employee who experiences an injury or illness will report the incident to his/her supervisor (or cause notification to be given) during the shift in which it occurs.

B.

Employees are required to justify delays in reporting events.

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3.2.3

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Ensure Prompt Medical Treatment A.

The initial responsibility of the manager in charge of the workplace is to ensure that the injured employee(s) receives appropriate and timely medical attention. In situations where the need for medical attention is not blatantly obvious, supervisors may exercise judgment. However, if there is any doubt, supervisors must not hesitate in taking and accompanying the employee to the nearest TVA health station, medical vendor, or other provider for treatment.

B.

An injured employee’s immediate supervisor monitors medical treatment until the individual can return to productive status. This responsibility includes ensuring that TVA’s policy of light or limited duty is communicated to the attending physician, consistent with TVA’s Return to Work Practice.

Classify and Record Incident A.

The manager in charge of the workplace classifies and records injuries and illnesses as defined in this process and as required in 29 CFR 1904.

B

All injuries and illnesses are recorded on OSHA form 300. A copy of the OSHA form 300 and instructions for making entries is at Appendix B.:

C.

Injuries or illnesses are recorded on OSHA form 300 by the manager in charge of the workplace within three calendar days of determining that the event is recordable. A OSHA form 300 is prepared for each calendar month and provided electronically to Muscle Shoals IS within three calendar days after the end of the month.

D.

TVA employee injuries or illnesses are charged to the employee’s official work station, as defined by the ten-digit organizational structure code assigned to the individual at the time of the accident.

E.

Work-related injuries and illnesses reported to WIIS for TVA employees are reconciled quarterly with OWCP d ata by Corporate Safety. If classification is unclear or disputed, the DASHO makes the final determination. All cases, including those controverted by management, are reported on OSHA form 300. Organizations may delete those case(s) subsequently denied by OWCP if they do not otherwise meet the recordability criteria defined in this process.

F.

A serious accident includes: 1.

A fatality or in-patient hospitalization of three or more TVA employees or augmented employees under TVA Supervision within 30 days of an accident. Corporate Safety reports these incidents to OSHA within 8 hours of the event.

2.

Any event which under slightly different circumstances could have resulted in a serious accident as defined above may upon agreement by the DASHO and the responsible executive vice president (EVP) and based upon advice from Corporate Safety and the safety consultant/representative of the organization be considered a serious accident.

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3.2.5

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Investigate Incidents A.

Serious accidents a re investigated in accordance with TVA-SPP-18.010.

B.

If an injury/illness occurs (or a near miss that could have resulted in an injury/illness) and is determined not to be a serious accident, it is promptly and thoroughly investigated by the manager in charge of the workplace. The investigation’s objective is to identify root cause(s) and develop countermeasures or recommendations to prevent recurrence -- not to place blame or find fault with individuals or organizations.

C.

A form TVA 18120, TVA Injury/Illness Investigation Report, (Appendix D) is prepared for all occupational injuries/illnesses identified in section “A” of the form.

D.

A group is appointed by the manager in charge of the workplace to conduct the investigation. The group consists of the responsible first level supervisor who serves as leader and an appropriate number of other employees who are familiar with the work being performed at the time of the incident. The organization’s safety consultant/representative may serve as an advisor to the group but will not be a member. The investigation is initiated as soon as possible but within 24 hours of the occurrence (unless extended by the manager in charge of the workplace). This group will collect information, identify causes and develop necessary corrective action.

E.

Results of the investigation are documented on form TVA 18120. When the form is completed, this material is provided to the organization’s safety consultant/representative for a review for adequacy. When the organization’s safety consultant/representative is satisfied that the form1. is adequate, he/she sends it to the manager in charge of the workplace for final review and approval. This manager is encouraged to call upon the local health and safety committee, central safety management review team, or similar groups to assist in the review and approval of investigations.

F.

The original form TVA 18120 for occupational injuries and illnesses is provided to IS within 10 workdays after classification. These forms may also be completed electronically through features available on the “TVA Safety Resource Network.”

G.

Forms TVA 18120 determined to be inadequate by Corporate Safety are returned for revision2

Analyze Trends and Provide Periodic Reports A.

Corporate Safety oversees data entered into WIIS for forms OSHA 300 and TVA 18120 within five work days following the end of the month.

B.

Corporate Safety uses this data to produce several monthly and ad hoc reports and analyses for management and, as appropriate, health and safety

1

Any unresolved differences with the group will be noted by the organization’s safety consultant/representative and forwarded to the manager in charge of the workplace. 2 Forms are returned to the safety managers of TVA organizations.

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committees, labor representatives, and OSHA. These reports provide information on TVA and organization incidence rate experience, injury/illness demographics, supervisory accident experience3, root causes, countermeasures, replication opportunities, etc. C.

A number of reports are available by the seventh of each month and are posted on the “TVA Safety Resource Network.”

D.

Each establishment / organization shall post OSHA Form 300A, “Summary of Work Related Injuries and Illnesses,” required by 29 CFR 1904 by February 1st of each year and must remain posted until April 30th.

E.

These reports and analyses are reviewed for local and system-wide trends and other items of significance. Appropriate countermeasures are developed and implemented by TVA management.

F.

TVA management reviews the supervisory accident experience report4 and acts to determine causes for unfavorable trends, taking corrective action as required.

G.

Injury/illness incidence rates are reported to TVA management and others based on data in WIIS at the time of inquiry. Incidence rates are calculated using the following formula.

EXAMPLE Incidence Rate = Number of events X 200,000 work hours Employee hours worked during the reporting hours H. 3.2.7

3.2.8

Implement Solutions A.

In conjunction with the employees involved, the manager in charge of the workplace implements solutions identified to address root causes identified in accident investigations and assesses results to verify elimination or reduction of root cause(s) and achievement of desired improvement levels.

B.

If results achieved are determined not to be acceptable, the manager in charge of the workplace and the work group involved revisit the implementation methodology and/or investigation to identify opportunities for improvement.

Standardize or Replicate Solutions A.

3

Typically, incidence rates are calculated for the frequency of occurrence of lost-time, recordable, and all injury events (See Definitions).

When a determination is made that acceptable results have been achieved from an injury/illness investigation, the manager in charge of the workplace, in conjunction with employees involved, establishes and implements a strategy

This report will track a supervisor’s safety performance by tracking the accident experience of employees working for that supervisor. 4 This report provides information regarding each supervisor’s safety performance by tracking the accident

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for ensuring that solutions developed become part of daily work. This strategy may involve implementing design changes that eliminate the hazard or control it to an acceptable level through the use of safety or warning devices. The strategy may also involve development of procedures and standards or a process control system, training and education to ensure that employees understand why a new/modified process is needed and how to use it, and appropriate monitoring and tracking.

3.2.9

4.0

B.

The safety consultant/representative of the responsible TVA organization periodically reviews the new/modified process to ensure that it is functioning as intended.

C.

If the manager in charge of the workplace determines that the new/modified process may benefit other locations, a recommendation is made concerning replication of new/modified processes.

D.

EVPs and/or staff evaluate recommendations made.

E.

If EVPs and/or staff determine that implementation of a recommendation is appropriate at other locations, a roll out plan is developed and initiated at the selected location(s). The manager in charge at the selected location(s) standardizes the new or modified process.

Evaluate Process A.

The effectiveness of this process will be assessed at all organization levels through periodic evaluations.

B.

Corporate Safety evaluates effectiveness of this process at least once every three years.

DEFINITIONS All injury rate (AIR) - the number of work-related injuries or illnesses resulting in either a fatality, days away from work/lost-time, restricted duty/job transfer, medical treatment, loss of consciousness, other significant work-related injury / illness diagnosed by a physician or other licensed health care professional, or other compensable incident per 200,000 hours worked. Incidence rate - the number of work-related injuries or illnesses resulting in a particular outcome, or severity, per 200,000 hours worked. Days Away From Work/Lost-time incidence rate (LTIR) - the number of workrelated injuries or illnesses resulting in either a fatality, days away from work/losttime, restricted duty/job transfer per 200,000 hours worked. Manager in charge of the workplace - the most senior manager of a TVA plant or other facility, area, property, major work activity, etc. OSHA recordable incidence rate (ORIR) - the number of work-related injuries or illnesses resulting in either a fatality, days away from work/lost-time, restricted duty/job transfer, medical treatment, Loss of Consciousness, other significant workrelated injury / illness diagnosed by a physician or other licensed health care professional per 200,000 hours worked. III-139

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Work Injury/Illness System (WIIS) - TVA’s centralized data base for maintaining records of injuries and illnesses and reporting results to managers and other employees.

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Appendix A Page 1 of 1 Are there situations where an injury or illness occurs in the work environment and is not considered work-related? Yes, an injury or illness occurring in the work environment that falls under one of the following exceptions is not work-related, and therefore is not recordable. 1904.5(b)(2)

You are not required to record injuries and illnesses if . . .

(i)

At the time of the injury or illness, the employee was present in the work environment as a member of the general public rather than as an employee.

(ii)

The injury or illness involves signs or symptoms that surface at work but result solely from a non-work-related event or exposure that occurs outside the work environment.

(iii)

The injury or illness results solely from voluntary participation in a wellness program or in a medical, fitness, or recreational activity such as blood donation, physical examination, flu shot, exercise class, racquetball, or baseball.

(iv)

The injury or illness is solely the result of an employee eating, drinking, or preparing food or drink for personal consumption (whether bought on the employer's premises or brought in). For example, if the employee is injured by choking on a sandwich while in the employer's establishment, the case would not be considered work-related. Note: If the employee is made ill by ingesting food contaminated by workplace contaminants (such as lead), or gets food poisoning from food supplied by the employer, the case would be considered work-related.

(v)

The injury or illness is solely the result of an employee doing personal tasks (unrelated to their employment) at the establishment outside of the employee's assigned working hours.

(vi)

The injury or illness is solely the result of personal grooming, self medication for a nonwork-related condition, or is intentionally self-inflicted.

(vii)

The injury or illness is caused by a motor vehicle accident and occurs on a company parking lot or company access road while the employee is commuting to or from work.

(viii)

The illness is the common cold or flu (Note: contagious diseases such as tuberculosis, brucellosis, hepatitis A, or plague are considered work-related if the employee is infected at work).

(ix)

The illness is a mental illness. Mental illness will not be considered work-related unless the employee voluntarily provides the employer with an opinion from a physician or other licensed health care professional with appropriate training and experience (psychiatrist, psychologist, psychiatric nurse practitioner, etc.) stating that the employee has a mental illness that is work-related.

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APPENDIX B

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APPENDIX C Page 1 of 8 SAMPLE COMPLETED FORM TVA 18120, TVA INJURY/ILLNESS INVESTIGATION REPORT TVA 18120 TVA INJURY/ILLNESS INVESTIGATION REPORT Instructions NOTE: Because this form contains “Sensitive Information,” all completed versions, hardcopy and electronic MUST be protected. Electronic versions should either be immediately deleted from the hard drive or password protected. To protect information that has been entered and to make a “Read Only” document, go to FILES, SAVE AS. Within “SAVE AS” dialog box and to the right of the “Save In” box, click on TOOLS and select SECURITY OPTIONS, type in Password to Open and Password to Modify. Click box that says “Read-Only Recommended.” Choose OK to save the document. Then choose SAVE. CAUTION: When a document is “Password Protected,” no one can open or change the document including you without the correct password. Don’t forget your password.

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APPENDIX C Page 2 of 8 SAMPLE COMPLETED FORM TVA 18120, TVA INJURY/ILLNESS INVESTIGATION REPORT

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APPENDIX C Page 3 of 8 SAMPLE COMPLETED FORM TVA 18120, TVA INJURY/ILLNESS INVESTIGATION REPORT

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APPENDIX C Page 4 of 8 SAMPLE COMPLETED FORM TVA 18120, TVA INJURY/ILLNESS INVESTIGATION REPORT

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APPENDIX C Page 5 of 8 SAMPLE COMPLETED FORM TVA 18120, TVA INJURY/ILLNESS INVESTIGATION REPORT

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APPENDIX C Page 6 of 8 SAMPLE COMPLETED FORM TVA 18120, TVA INJURY/ILLNESS INVESTIGATION REPORT

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APPENDIX C Page 7 of 8 SAMPLE COMPLETED FORM TVA 18120, TVA INJURY/ILLNESS INVESTIGATION REPORT GENERAL INSTRUCTIONS Section A - REQUIRED: Enter the injured employee’s name; social security number; the date and time of the incident; supervisor’s name; supervisor’s SSN; and injury/illness classification. NOTE: Shaded blocks or text are optional for organizational use only. Section B - Provide incident narrative. Inclusion of a sketch or photograph is optional. Section C - Preaccident/Incident Activity - Check up to three codes that most accurately reflect the activity in which the employee was engaged immediately before the incident. Equipment/Tools Involved - Check up to three codes that describe the equipment that was directly involved in the incident. Equipment Failure - Check up to three codes that identify how the equipment involved in the incident failed. Hazard Involved - Check up to three codes that identify the hazard(s) that resulted in or caused the injury. In some cases one source of energy may interact with or trigger another to produce the injury. For example, an employee may receive a low-voltage electrical shock from a drill motor that caused a fall from a ladder. In this case, both code 80, “electric AC below 600 volts,” and code 02 “falls, different level,” should be checked. Unsafe Act/Condition - Check one code from each of the categories. For example, an employee operating a bench grinder received an eye injury. It was found that the grinder guard was not in place, the employee was not wearing a face shield, and was not following a written shop procedure for grinding operations. Codes 07, “guard not in place,” 32, “did not use PPE,” and 42, “procedures/standards/methods not followed,” would all be selected, while codes 23 and 54, “not a factor,” would be marked under the “warning devices” and “administrative controls” categories. Changes in Workplace - Change that occurs in the workplace can create new or unforeseen hazards, even in tasks or operations that are considered routine. Identifying these changes can give managers insight into underlying sources of hazards and suggest actions that can be taken to prevent recurrence. Compare the task or operation that precedes an incident with the planned or normal procedure and describe any differences. Evaluate these differences as possible contributors to the incident. If the differences contributed to the incident, check “yes” on the form. If not, check “no.” Section D - Describe the root cause of the incident. Completion of this section is optional. Section E - This section is to be completed by the investigator’s supervisor through discussions with all parties involved. Review all realistic areas for preventive action. Examine unsafe act/conditions and changes identified in Section C for methods or ways to prevent recurrence. Examine unsafe acts or errors on the part of any employee to determine why they occurred. List those actions in “A” that are within your scope of authority that you will take to prevent this type of incident from happening again. After each action, list the person and/or organization responsible for taking the action along with an estimated completion date. List those action in “B” that you believe should be implemented, even if you cannot make these changes yourself, e.g., changes to procedures, protective equipment, training, or equipment design. These actions do not usually produce immediate results but prevent similar incidents at other locations. If possible, list the person or organization responsible for such corrective action and an estimated completion date. Attach as many continuations sheets as necessary. Section F - Assess the effectiveness of implementation of recommendations identified in Section E. Completion of this section is optional Section G -Assess the degree to which solutions implemented have become part of daily operations. Identify any opportunities for replication. Completion of this section is optional. Section G - Assess the degree to which solutions implemented have become part of daily operations. Identify any opportunities for replication. Completion of this section is optional.

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APPENDIX C Page 8 of 8 SAMPLE COMPLETED FORM TVA 18120, TVA INJURY/ILLNESS INVESTIGATION REPORT

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APPENDIX D

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Annex B Electrical Switching Operation The following materials have been obtained from The Tennessee Valley Authority (TVA), Reference Document Procedure Number 1003, Revision 0, January 6, 2003.

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Electrical Switching Operations 1.

Purpose

1.1.

The purpose of this procedure is to establish requirements for electrical switching operations.

2.

Instructions for Electrical Switching

2.1.

During normal plant operations, permission shall be obtained from appropriate operations personnel before employees may enter the switchyard.

2.2.

The appropriate operations personnel shall approve the entry based on work requirements, operational conditions, and the safety of the work to be done. Proper clearances will be obtained in accordance with the most current clearance procedures, practices and operating letters.

2.3.

Supervisors shall ensure that employees under their supervision work within safe boundaries established by the clearance, and in accordance with the most current clearance procedures, practices and operating letters (if such is applicable).

2.4.

Supervisors shall ensure that employees wear the appropriate flame retardant clothing and required personal protective equipment when conducting switching operations.

2.5.

Supervisors shall ensure that proper barricades and barrier tape procedures are followed in accordance with TVA Safety Procedure 602, “Barricades and Barriers (Temporary)”.

2.6.

During outages or heavy maintenance activities in the switchyard, the supervisor shall notify the appropriate operations personnel of the activity being performed on a daily basis. Supervisors are responsible for ensuring that employees under their supervision establish and work within safe boundaries.

2.7.

If switching becomes necessary while work is being performed in the switchyard, the appropriate operations personnel shall notify the supervisors and crews of the work being performed to evacuate the switchyard.

2.8.

When the appropriate operations personnel becomes aware of adverse weather conditions that could cause breakers to open automatically, they shall notify the responsible supervisor to evacuate the switchyard.

3.

Reference

3.1.

29 Code of Federal Regulations 1910.269, “Electric Power Generation, Transmission and Distribution”.

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Annex C Temporary Protective Grounding for Generating Stations and Other Non-Transmission Facilities The following materials have been obtained from The Tennessee Valley Authority (TVA), Reference Document Procedure No. 1008, Revision 5, July 15, 2006.

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Temporary Protective Grounding for Generating Stations and Other Non-Transmission Facilities 1.

Purpose

1.1

The purpose of this procedure is to establish standardized requirements for temporary protective grounding (protective grounding) on de-energized electrical conductors or equipment15. The requirements provide for (1) employee safety when working on deenergized electrical conductors and equipment that could be inadvertently energized, (2) protection against hazardous induced voltage and (3) prevention of the re-accumulation of electrical energy in capacitive devices.

1.2

This procedure applies to temporary protective grounding for generating stations and other non-transmission electrical conductors and equipment. Protective grounding requirements for transmission electrical lines and equipment are being developed in safety procedure Temporary Protective Grounding for Transmission Lines and Equipment.

2.

Roles and Responsibilities

2.1

Operation and maintenance managers are responsible for ensuring that employees who perform protective grounding tasks are trained on this procedure and implement this procedure within their area of responsibility.

2.2

The Safety Process Ownership Team (POST) is responsible for developing and maintaining this procedure. The Safety POST is an Agency-wide team composed of representatives from COO, CS&M, ADMIN, and Corporate Safety that is responsible for developing and maintaining safety policies/procedures.

2.3

The supervisor and/or foreman who assign protective grounding tasks is responsible for their employee’s compliance with this procedure.

2.4

The electrical engineering resource staff that supports the plant or facility is responsible for providing the maximum available bolted fault current and circuit clearing time values for the correct selection of ground cable size at the grounding location.

2.5

Employees who perform grounding tasks are responsible for performing the tasks in accordance with this procedure.

3.

Qualified Persons

3.1

Only trained and qualified electrical workers or technicians may apply protective grounds in accordance with this procedure. Currently qualified electrical workers who are on local official plant clearance list as designated by management will be retained and may apply protective grounds. All future qualified electrical workers as of June 30, 2006, who apply protective grounds or a supervisor who supervises the application of protective grounds must be trained on the contents of this procedure and the training documented in the Human Resources Information System - Automated Training Information System (HRIS¬ATIS). The electrical worker/supervisor must be trained in accordance with TVA Safety Procedure 424 “Grounding Safety Procedures Course Standard”.

15

TVA employees working on non-TVA conductors, equipment, facilities, or systems adhere to this procedure.

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4.

Identify Electrical Information

4.1

Prior to applying protective grounds, identify the electrical characteristics of the electrical conductors and equipment to be worked including the nominal voltage, the maximum available fault current, the time to clear the maximum available fault on the circuit, and any stored electrical energy (capacitive devices)16. Obtain a current single line diagram of the electrical circuit to be worked.

5.

Determine the Need for Protective Grounding

5.1

Low Voltage Circuits (600 V and below) without a capacitive device(s) or induced voltage

5.2

Protective grounds are not installed. Attempting to use protective grounds on low voltage electrical conductors and equipment creates a greater hazard to employees due to the limited approach distances, close proximity between conductors and grounded parts, and the size of the ground cable. Therefore, place the low voltage circuit in an electrically safe condition by de-energizing the circuit from all sources of electrical energy and testing for the absence of voltage. It is critical to either create an electrically safe condition before touching/contacting the low voltage circuit or use live-line work methods such as rated gloves and/or insulation.

5.3

Low Voltage Circuits (600 V and below) with a Capacitive or Inductive Voltage

5.4

In circuits with capacitive device(s) and/or hazardous induced voltage present, protective grounds are to be installed in accordance with this procedure to create an electrically safe condition. Since low voltage grounding sets are used to prevent dangerous levels of voltage developing on the conductor or part, they are not required to be rated to carry the maximum available short circuit current.

5.5

Medium Voltage Circuits (greater than 600 V to 22 kV)

5.6

Protective grounds are installed in accordance with this procedure to create an electrically safe condition.

6.

Fabricate or Purchase Protective Grounds

6.1

New or repaired protective ground sets must meet the specifications in Appendix B. Existing protective ground sets can remain in service provided that the ampacity of the cable and clamps meet the requirements of Table 1.

7.

Select Protective Ground

7.1

Minimize Length of Protective Ground

7.2

Protective ground cables must be as short as possible to reduce hazards created by the physical whipping action of the cables should they be inadvertently energized. Protective grounds longer than 12.19 meters will not be used.

7.3

Never use two or more grounds connected together in series to make a longer ground.

7.4

Do not coil protective ground cables when in use17.

16 17

This information can be obtained from electrical engineering studies or the responsible electrical engineering staff. Coiling protective grounds increases the impedance under fault conditions thus decreasing employee protection.

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8.

Determine Fault Current and Clearing Time

8.1

Protective grounds must be capable of conducting the maximum available fault current for time necessary to clear the fault at the grounding location except in low voltage circuits and equipment18. The values of the worst case, maximum available fault current and the time duration to clear that fault are obtained for the grounding location. This information can be obtained from electrical engineering studies or the responsible electrical engineering staff.

9.

Select the Clamp for the Location

9.1

Use the appropriate ground cable clamps when connecting to different surface shapes found on bus, conductor, structure, etc.

10.

Size the Protective Ground Cable

10.1

For medium voltage equipment, select the size of protective grounds based on their ultimate current carrying capacity. Select from Table 1, a cable size which has an ultimate current capacity equal to or greater than the circuit’s maximum available fault current, at the clearing time equal to or greater than the circuit’s clearing time. If the circuit’s fault current and/or clearing time is not within the range of Table 1, consult the electrical engineering resource staff responsible for the generating station or facility.

10.2

Where the available fault current is greater than a 4/0 cable’s ultimate current carrying capacity at the required number of cycles, parallel ground sets must be used. A 90% derating factor is used for multiple ground sets. See Table 2 for the current carrying capacities of parallel ground sets.

10.3

For low voltage (600 V and below) equipment, a #2 AWG or larger stranded, copper cable having a 600 V rated covering may be used to discharge hazardous stored energy and ground the circuit to prevent re-accumulation of electrical energy in the capacitor or to eliminate hazardous induced voltage on a circuit.

Table 1 Single Grounding Cable Capacities Cable Size

Ultimate Current Carrying Capacity of Copper Cable (kA, Asymmetrical. RMS, 60 Hz)

6 cycles 15 cycles 30 cycles (100 ms) (250 ms) (500 ms) #2 AWG 23 17 13 1/0 36 26 20 2/0 46 33 26 19 4/0 72 43 41 Source: ASTM F855-90, Table 3a. X/R=40, D.C.offset=92%

60 cycles (1 s) 9 15 19 30

18

In low voltage equipment, the purpose of the ground cable is to discharge stored energy and prevent reaccumulation of electrical energy. Therefore, fault current and clearing time are not factors. 19 The ampere capacity of the ground set is limited by the ampere rating of the clamp being used: 43 kA at 15 cycles.

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Table 2 Parallel Grounding Cable Capacities Cable Number and Size

2-1/0 2-2/0 2-4/0 3-4/0 11.

Ultimate Current Carrying Capacity of Copper Cable (kA, Asymmetrical. RMS, 60 Hz) 6 cycles (100 ms) 65 83 130 194

15 cycles (250 ms) 47 59 77 116

30 cycles (500 ms) 36 47 74 111

60 cycles (1 s) 27 34 54 81

Test Protective Grounds

11.1. Protective grounds sets are tested in accordance with Appendix C and must be marked with the current test date. Before using a protective ground set, the current test date must be checked. If the test date is not current, the protective ground set is taken out of service. 12.

Inspect Protective Grounds

12.1. A defective protective ground or one that has been subjected to a fault is removed from service20. Visually inspect protective grounds for defects as follows:

13.

•

Damage to cable, i.e., burned jacket, broken copper strands, especially near the cable termination, damaged or loose cable termination’s, evidence of cable corrosion.

•

Damage to clamp mechanisms, i.e., sharp edges, cracks, splits, or other defects and for smooth operation and excessive looseness.

•

Damage to clamp jaws, eye screws, and T-handle screws, i.e., cleanness and freedom from dirt, oil, grease, or corrosion.

Select Personal Protective Equipment (PPE)

13.1. Employees who install protective grounds wear the PPE based on an arc flash hazard analysis for the electrical conductors and equipment. The Arc Flash Hazard Calculation and Protection Analysis (AFHCP) procedure is being developed and will be issued in January 2003. Until the operating organizations implement the AFHCP, existing organizational FR requirements are used. 14.

De-Energize Conductor or Equipment

14.1. Ensure that the electrical conductors and equipment are isolated from all energy sources in accordance with the operating organization’s clearance procedure before installing the grounds. Electrical conductors and equipment are considered as energized until they have been isolated, tested for absence of nominal voltage, and protective grounds installed (including low voltage equipment where grounds may be required).

20

Defective protective grounds are destroyed or repaired in accordance with Appendix B. A ground cable that has been subjected to a fault is always destroyed, but the clamp may be reused if not damaged.

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15.

Verify Equipment

15.1.

Ensure that the correct equipment, bus, part, conductor, etc. to be grounded has been identified at the grounding location. A work plan or package21 which identifies the grounding location and the conductors and/or equipment to be grounded is prepared in accordance with the organization’s work management system. The work plan must include drawings showing the proposed installation points for the grounds and the sequence of operations involved in the grounding work. The plan should anticipate the requirement for more than one equipotential work zone to be established if there is a necessity to open/break the electrical circuit possibly isolating employees from the protective grounds. NOTE: Prior to installing temporary protective grounds at Fossil Power Group (FPG) plants, a written plan detailing where the temporary protective grounds will be placed must be submitted and approved by the manager responsible for performing the work and the manager at the plant responsible for the grounding. This plan must include a Job Safety Analysis (JSA) prepared in accordance with TVA Standard Programs and Processes (SSP) 18.005, “Plan Jobs Safely,” a generation sensitive activity sheet (if applicable), electrical diagrams, and a description of the work to be accomplished. A pre-job safety briefing (SSP 18.005) on the installation of the temporary protective grounds must be conducted with all involved personnel.

16.

Dissipate Stored Electrical Energy

16.1.

Electrical conductors and equipment with stored electric energy of 0.25 joules or greater22 require the capacitance elements (capacitors) to be short-circuited to dissipate the stored energy. All energy sources are placed in an electrically a safe condition. For example, capacitors are discharged and high capacitance elements (10 joules or greater) are short-circuited and grounded. Use live-line tools when short-circuiting capacitors or a ground switch provided for this purpose. If the operating voltage of the capacitor is greater than 50 V, then a five-minute waiting period is required between de-energizing the capacitor and applying the ground connection.

17.

Test for Absence of Voltage

17.1.

All electrical conductors and equipment are considered energized until they are verified to be de-energized by testing23 and protective grounds installed. The electrical conductors and equipment are tested with a voltage detection instrument24 prior to installation of temporary protective grounds. The voltage detector must be rated for the nominal voltage to be measured and set for that voltage before taking a reading. When testing for the presence of voltage, do not use tape or insulation penetrating methods. Test the voltage

21

The requirement for a work plan or package is considered met if the grounding process is covered as a part of another work order. 22 Stored energy – A discharge of energy exceeding 0.25 Joules (J) is above the threshold of perception, 10 J is hazardous to body organs; and 50 J is potentially lethal. The amount of stored energy in a capacitor can be calculated by the equation, E=1/2(CV2), where E is the stored energy (J), C is the capacitance (Farads), and V is nominal voltage (volts). The operating voltage and the capacitor’s capacitance are usually on the equipment nameplate. 23 Electrical testing is done in accordance with the operating organization’s electrical safety requirements/practices. 24 For medium voltage systems, use the TVA standardized voltage detector listed on products standardization list or a phasing meter.

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detector on a known energized source to check proper operation, before and after testing the electrical conductors or equipment to be grounded. When the electrical conductors and equipment to be grounded are tested, the test must show an absence of nominal voltage. If nominal voltage is detected, paragraph 11 has not been properly implemented, contact a supervisor immediately to resolve the problem. The presence of nominal voltage at this step is considered a “near miss” incident and must be reported, investigated, and corrective action developed and implemented. 18.

Account for Installed Protective Grounds

118.1. When protective grounds are installed, each ground or grounding device is identified with a metal disk or Lamicoid for purposes of tracking the ground and ensuring removal of all grounds before re-energizing the electrical conductors and equipment. The organization’s grounding accountability process or clearance procedure is followed for identifying and recording installation of the grounds25. 18.2. At generating plants, the electrical representatives authorized by the plant/site management official-in-charge are the only personnel who may receive and return ground discs. 19.

Install Protective Grounds

19.1.

After determining the absence of nominal voltage, proceed with placement of protective grounds. Protective grounds are placed in such a manner as to prevent any employee working on the electrical conductors and equipment from being exposed to hazardous differences in electrical potential, thus establishing an equipotential work zone. Another equipotential work zone must be established by installing a second set of protective grounds any time there is a necessity to open/break the electrical circuit isolating any employee from protective grounds.

19.2.

When parallel ground sets are used for current carrying capacity purposes, they must be of equal size and length and connected to the conductor and ground as close to the same point as possible. The ground cables must be tied together every 90 cm (3 ft) with a nonmetallic material to restrain the mechanical movement forces should the cables be energized.

19.3. Solid metal-to-metal connections are essential between the ground cable clamps and the connection points. Since corrosion and paint can cause a poor electrical connection, the grounding surface connection point must be free of rust, corrosion, non-conductive paint, or other insulating material or otherwise cleaned. 19.4. Protective grounds are installed on conductors and equipment as follows (See paragraph 19.9 for the preferred method to ground metal clad switchgear.): Connect the ground-end of the ground cables to a facility ground point that is connected to the ground grid. If a cluster block is used it must be secured from movement in case of a fault condition.

25

For generating stations, ground tags are issued in conjunction with a specific clearance number.

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Connect the clamp on the line-end of the ground cable to the nearest phase conductor or equipment part using a live-line tool26. Maintain the minimum approach distances in Table 3 to the conductor or equipment being grounded or to any other exposed energized conductors or parts. Do not handle the ground by hand or allow bodily contact with the ground cable while making the line-end connection. Repeat the instructions in 1 and 2 above, proceeding outward and upward until all conductors are grounded. All electrical phases of the electrical equipment are required to be grounded. Protective grounds must be kept as short as reasonably possible and installed so as to hang as straight as possible with no folds or sharp bends. Folds or bends increase the mechanical and impedance hazards should a fault occur. Table 3 – Minimum Approach Distances Nominal Voltage (Phase-to-Phase) 300 V and less Over 300 V to 750 V Over 750 V to 2 kV Over 2 kV to 15 kV Over 15 kV to 36 kV Over 36 kV to 46 kV Over 46 kV to 72.5 kV Over 72.5 kV to 121 kV Over 121 kV to 145 kV Over 145 kV to 169 kV Over 169 kV to 242 kV Over 242 kV to 362 kV Over 362 kV to 550 kV Over 550 kV to 800 kV

Minimum Clearance Distances (Phase-to-Ground) Avoid Contact 30 cm 46 cm 64 cm 71cm 79 cm 91 cm 97 cm 107 cm 122 cm 160 cm 259 cm 284 cm27 458 cm

19.5.

A power circuit breaker may not be used to “extend” a protective ground to prevent an employee from being isolated from their protective ground.

19.6.

Locate protective grounds as close as practical to the work area. This is particularly important on long runs of cable where induced voltage is likely to be present.

19.7.

Non-current carrying metal parts of equipment or devices, such as transformer cases and circuit breaker housings, are treated as energized at the highest voltage the equipment operates, unless an inspection of the grounding strap prior to work being performed determines that these parts are grounded.

26

Live-line tools must have a current test date. Rated, rubber protective gloves are not considered live-line tools. A switching over-voltage factor of 2.2 allows the distance to be reduced from 342.90 centimeters to 302.26 centimeters.

27

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19.8.

Power circuit breakers with internal capacitors must have the grounds installed and the breaker closed to discharge the capacitors.

19.9.

In metal clad switchgear, the preferred method of grounding is the use of “ground and test device” equipment specifically designed a manufacturer or approved by a PE for this application. Operating organizations must develop a written procedure establishing the proper use of the grounding and test device in accordance with the requirements of this standard. Live-line tools may be used to place protective grounds, if ground and test devices are not available. In either case a written step-by-step procedure is required.

20.

Place Signs and Barricades

20.1.

Orange barricade tape with the legend “DANGER ELECTRICAL HAZARD AUTHORIZED PERSONNEL ONLY” is used to designate an area where an electrical hazard is present. It means “do not cross” for all persons except those qualified and authorized to work on or near the energized equipment. The tape must be used to designate energized, exposed conductors or parts and energized equipment which poses an electrical hazard to the employees working on the grounded conductors or equipment. The tape is installed horizontally (preferably at a height of 120 cm above ground level/work surface) and other locations (vertically) as necessary to fully identify any electrical hazard adjacent to the grounded equipment work area.

20.2. Danger and caution signs are used to identify hazardous areas in and around the work site. If a protective ground set or grounding device is inside an electrical cubicle/cabinet and the door is closed, a sign that states, “GROUNDS INSTALLED – REMOVE BEFORE ENERGIZING,” is posted on the cubicle/cabinet. All signs must be designed in accordance the requirements contained in ANSI Z535.2, Environmental and Facility Safety Signs. 21.

Remove Protective Grounds Temporarily

21.1.

If temporary removal of the grounds is required, all employees that will be affected by the removal of the grounds are informed of impending removal. After notification, the grounds are removed in accordance with paragraph 22. and in accordance with the operating organizations clearance procedure.

22.

Protect Employees during Temporary Ungrounded Periods

22.1.

While grounds are temporarily removed, protect all employees from the hazards of exposed energized conductors or parts. Employees will maintain the minimum approach distance of Table 3 or use energized work methods/practices on the exposed energized conductors or parts.

23.

Determine Requirement for Protective Grounds

23.1.

Protective grounds must be reapplied in accordance with paragraph 16, if additional work is to be performed. If no additional work is required, remove all protective grounds in accordance with paragraph 22.

24.

Remove Tools, Signs, Barricades

24.1. Before the protective grounds are removed, move any tools, signs, or barricades to beyond the minimum approach distance in Table 3.

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25.

Remove Protective Grounds

25.1.

The standard for removal of grounds is as follows:

Part III: Worker Safety Rules

•

The line-end of the ground cable furthest away from the employee’s work position is disconnected first using a live-line tool28. Do not approach closer than the minimum approach distance in Table 3 to the conductor or part being ungrounded or to any energized conductors or part. Do not handle the ground by hand or allow bodily contact with the ground cable while removing the line-end connection.

•

The ground-end of the ground cable is then disconnected.

Repeat the instructions in A and B above, proceeding inward and downward until all protective grounds are removed. 26.

Account for All Protective Grounds

26.1.

Account for all protective grounds to ensure that they have been removed to prevent possible breaker or fuse operation. When protective grounds or grounding devices are installed, each ground is identified with a disk for purposes of tracking the ground and ensuring removal of all grounds before re-energizing the conductors or equipment. The organization’s grounding accountability process or clearance procedure is followed for identifying and recording removal of the grounds.

27.

Energize Electrical Conductors and Equipment

27.1.

After releasing the clearance in accordance with organization requirements, energize the electrical conductors and equipment in accordance with the organization’s operating or testing procedure.

28.

Inspect and Store Protective Grounds

28.1. After each use, visually inspect the protective grounds for damage and perform the following: 28.1.1. Wipe the ground cable clean. 28.1.2. Coil the ground cable neatly, beginning from the same end of the cable each time29, if possible, to avoid kinks the cable. 28.1.3. Store the ground cable so as to avoid damage. 29.

Definitions

29.1.

AWG - American Wire Gage, also known as the Brown and Sharp Gage. This gage has the feature that a larger number denotes a smaller wire. These numbers are not arbitrarily chosen, but follow the mathematical law upon which the gage is based.

29.2.

Bolted Fault Current -A short circuit or electrical contact between two conductors at different potentials, in which the impedance or resistance between the conductors is essentially zero. A short circuit condition that assumes zero impedance exists at the point of the fault.

28

Rated, rubber protective gloves are not considered to be live-line tools. This practice is not mandatory, the end of the cable to begin coiling will have to be marked/identified in some manner.

29

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29.3.

Circuit - A conductor or system of conductors through which an electric current is intended to flow.

29.4.

Conductor - A material, usually in the form of a wire, cable, or bus bar suitable for carrying an electric current.

29.5.

De-energized – Disconnected from all sources of electrical supply by open switches, disconnects, jumpers, taps, or other means. Note: De-energized conductors or equipment could be electrically charged or energized through various means, such as induction from energized conductors, portable generators, lightning, etc.

29.6.

Electric Arc Flash Hazard - A dangerous condition associated with the release of energy caused by an electric arc.

29.7.

Electrical Hazard - A dangerous condition such that contact or equipment failure can result in electric shock, arc flash burn, or blast injury.

29.8.

Electrical Worker (Electrically Qualified Person): A person who is knowledgeable of the construction and operation of specific equipment or work method and trained to recognize and avoid the electrical hazards that might be present with respect to that equipment or work method. Such a person is familiar with the proper use of precautionary techniques, personal protective equipment, insulating and shielding materials, insulated tools, and test equipment. A person may be considered qualified with respect to a certain piece of equipment but still be unqualified for others.

29.9.

Electrically Safe Work Condition - A state in which the conductor or circuit part to be worked on or near has been disconnected from energized parts, locked/tagged in accordance with established standards, tested to ensure absence of voltage, and grounded if determined necessary.

29.10. Energized (alive, hot, live) - A circuit that is connected to an electrical source or electrically charged so as to have potential different from that of ground. 29.11. Equipment - A general term including material, fittings, devices, appliances, fixtures, apparatus, and the like, as a part of, or in connection with, an electrical installation. 29.12. Equipotential - An identical state of electrical potential for two or more items. 29.13. Equipotential Worksite- The installation of protective grounds at the worksite in such a manner that the equipment, conductors, and the structure are interconnected by jumpers, grounds, ground rods, and/or grids to maintained safe voltage differences between all parts under worst-case conditions if it becomes energized. 29.14. Exposed (as applied to live parts) - Capable of being inadvertently touched or approached nearer than a safe distance by a person. It is applied to parts that are not suitably guarded, isolated, or insulated. 29.15. Fault Current - A current that flows from one conductor to ground or to another conductor owing to an abnormal connection (including an arc) between the two. A fault current flowing to ground may be called a “ground fault” current. See bolted fault current. 29.16. Flash Protection Boundary - A flash hazard protection boundary to be crossed by persons (at a distance from a live part) which, due to its proximity to a flash hazard, III-168

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requires the use of flash protection clothing and equipment when crossed. The flash protection boundary may be greater or less than the limited approach boundary. 29.17. Ground (earth, ground system, ground bus) - A conducting connection, whether intentional or accidental, by which an electric circuit or equipment is connected to the earth. It is used for establishing and maintaining the potential of the earth or approximately that potential. 29.18. Ground System (Grounding System) - Consists of all interconnecting grounding connections at a work site. 29.19. Grounded - Connected to earth, whether the connection is intentional or accidental. 29.20. Hazardous Stored Energy - A discharge of stored energy exceeding 50 joules into the human body is potentially lethal, greater than 10 joules can be hazardous, and as little as 0.25 joule is a considered a “heavy” electrical shock. Stored energy (E) can be calculated by E = ½(CV2), where E (Joules), C (Farads) and V (voltage). 29.21. Hazardous Induced Voltage – 50 volts or greater 29.22. Induction - The process of generating voltages and/or currents in conductive objects or electrical circuits by electric field or magnetic field induction. 29.23. Isolated - Physically separated, electrically, hydraulically, and mechanically, from all sources of electrical energy. Such separation may not eliminate the effects of electrical induction or stored electrical energy. 29.24. Joule (J) -A measure of energy, work, or quantity of heat: The work done by a force of 1 Newton acting through a distance of 1 meter. 29.25. Jumpering - The use of low-impedance conductors to make physical connections within, between, among, and around circuits and their associated equipment for the purpose of bypassing inadvertent currents around the workers and/or the worksite. Both grounding and jumpering are applicable to work on power plant and transmission systems, overhead and underground distribution systems, substations, switchyards, and with mobile equipment used in these work situations. 29.26. Minimum Approach Distance - When working at ground potential, it is the distance a qualified electrical worker and any conductive tool/material being maneuvered by the worker must be maintained from any energized exposed part or conductor. When working at an energized potential, it is the distance a qualified worker, the worker’s conductive tools/materials must be maintained from all objects or conductors at a difference in electrical potential (Table 3). 29.27. Parallel Protective Grounds - The use of two or more sets of protective grounds at the same location when the fault current capability exceeds the current carrying capacity of one set of temporary protective grounds. 29.28. Shock Hazard - A dangerous condition associated with the possible release of energy caused by contact or approach to live parts. 29.29. Temporary Protective Ground - Conductive devices to limit the voltage difference between any two accessible points at the work site to a safe value, and having a sufficient

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ultimate current capacity rating. The ground is installed on electrical conductors, buses, or parts of equipment for the protection of employees. 29.30. Temporary Protective Ground Set - A combination of cables, cable terminations, and clamps assembled for use in temporary protective grounding. A ground set consists of a ground end, insulated conductor, source/line end. The ground end consists of a clamp (typically the T-handle type) to be connected to a grounded structure or to a ground riser, and a cable termination. The flexible conductor has a suitable insulating jacket. The source end of the protective ground consists of a clamp (typically with “eye” bolt) to be connected with an insulating stick to a de-energized conductor, bus, or stud; or equipment part. 29.31. Temporary Protective Grounding Device (Switchgear) - A draw-out structure, equipped with a terminal set adjustable for both line or load positions, and a grounding connection. Connection to the local equipment ground bus is accomplished by engagement of ground on the draw-out structure, or by manually-installed cables. The grounding ends of the cables are terminated onto a suitable clamping device for connection to the local equipment ground bus within the structure. 29.32. Temporary Protective Grounding Device (Medium Voltage Contactors) - In NEMA E2 Medium Voltage (MV) controllers, the preferred method of grounding the load side is to use a “ground device” that “racks” into the equipment specifically designed by a manufacturer or approved by a PE for this application. The preferred ground device must have continuous and fully rated copper bus from the load-side pressure connectors to the ground pressure connector. The absence of voltage on the load-side connectors of the Medium Voltage Controller cubicle to be grounded must be confirmed prior to insertion of the grounding device. The preferred method of grounding the line side of the MV controller is the use of a “ground device” in the associated metal clad switchgear. Operating organizations must develop a written procedure establishing the proper use of the ground device. 29.33. Ultimate Rating (Capacity) - A calculated maximum current that a ground cable is capable of carrying for a specified time without fusing or melting. Grounds are generally rated by this value. It is expected that component damage may result. The component are not be reused. 29.34. Voltage (Nominal) - A nominal value assigned to a circuit or system for the purpose of conveniently designating its voltage class (as 120/240 volts, 480Y/277 volts, 600 volts). The actual voltage at which a circuit operates can vary from the nominal within a range that permits satisfactory operation of equipment. 29.35. Voltage (of a Circuit) -The greatest Root-Mean-Square (RMS) difference of potential between any two conductors of the circuit concerned. 29.36. Voltage to Ground - For grounded circuits, the voltage between the given conductor and that point or conductor of the circuit that is grounded; for ungrounded circuits, the greatest voltage between the given conductor and any other conductor of the circuit. 29.37. Working On (Live Parts) - Any activity inside the minimum approach distance which may include coming in contact with live parts with the hands, feet, or other body parts,

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with tools, probes, or with test equipment, regardless of the personal protective equipment a person is wearing. 30.

Reference

30.1.

Title 29, CFR Part 1910, Subpart I, Personal Protective Equipment.

30.2.

Title 29 CFR Part 1910.269, Electric Power Generation, Transmission, and Distribution.

30.3.

Title 29 CFR Part 1910, Subpart S, Electric Utilization Systems.

30.4.

Title 29 CFR Part 1910.137, Electrical Protective Equipment

30.5.

NFPA 70E, Standard for Electrical Safety Requirements for Employee Workplaces.

30.6. ASTM F855, Temporary Protective Grounds to be Used on De-Energized Electric Power Lines and Equipment. 31.

Appendix

31.1.

Appendix A Flow Chart

31.2.

Appendix B Grounding Set Specifications

31.3.

Appendix C Grounding Set Test Procedure

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APPENDIX A Page 1 of 1 FLOW CHART OF PROCEDURE

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APPENDIX B Page 1 of 2 GROUNDING SET SPECIFICATIONS Medium Voltage Protective Ground Sets 1.

Components for construction of medium voltage ground sets must comply with the current edition of ASTM F855. Acceptable components designed for special and/or specific use are available from vendors. Components that are normally used in TVA ground sets are shown in Table B-1.

Item Ferrule, Shrouded, plain plug type for 1/0 Cu Ferrule, Shrouded, plain plug type for 2/0 Cu Ferrule, Shrouded, plain plug type for 4/0 Cu Ferrule, Shrouded, threaded stud type for 1/0 Cu Ferrule, Shrouded, threaded stud type for 2/0 Cu Ferrule, Shrouded, threaded stud type for 4/0 Cu Heat Shrink Tube Clamp, Flat Grounding, T-Handle Clamp, C-Type Grounding Cable, Copper, TPE Jacketed, Yellow, 1/0 Cable, Copper, TPE Jacketed, Yellow, 2/0 Cable, Copper, TPE Jacketed, Yellow, 4/0 Clamp, Grounding, 6.35 centimeters Clamp, Grounding, 11.43 centimeters

Source A. B. Chance A. B. Chance A. B. Chance A. B. Chance A. B. Chance A. B. Chance A. B. Chance A. B. Chance A. B. Chance

Cat No. C600-2631 C600-2632 C600-2633 C600-2623 C600-2624 C600-2625 P600-1593 T600-3009 C600-2281

Allied Cable

TVA TIIC No. CGX-101P CGX-102M CGX-104H CEG-575P CEG-576M CGX-105F CGX-980A CFV-952L AJT-559P CEB-747E CGX-189D ABJ398A ABJ798X

2.

Use grounding clamps which require a copper ferrule to attach the cable. All protective ground set components that makeup a grounding set must have a current carrying capacity equal to or greater than the maximum fault current to which the grounding set may be subjected, i.e., the cable, clamps, and ferrules are rated equal to or greater than the same maximum expected current.

3.

Effective on the date of this procedure, new protective grounding cables will not have neoprene jackets. The paper or Mylar lining between the neoprene jacket and the copper strands can cause excessive corrosion in the copper stands. It has been found that these materials may contribute to a dangerous level of resistance in a ground set.

4.

Grounds made from braided copper conductor are prohibited.

5.

Proper installation of the ground-end clamp is critical to the current carrying capacity of the protective ground set. The shrouded ferrules must be crimped using the approved crimping dies as required by the ferrule manufacturer. The Section B crimp must be on the insulating jacket of the cable. Crimping dies for A. B. Chance ferrules are shown in Tale B-2.

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A. B. Chance Ferrule

Cable Size Section A Die

C600-2623

1/0

C600-2624

2/0

C600-2625

4/0

Table B-2 Section B Die

Burndy U165 or Alcoa 73AH Burndy U165 or Alcoa 73AH Burndy U166

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Cable Specification

Burndy U168 or 1/0, TPE jacketed, copper cable Alcoa 11AH Burndy U-L or 2/0, TPE jacketed, copper cable Alcoa 75AH Burndy U-L 4/0, TPE jacketed copper cable

Figure 1 6.

After attaching a ferrule, apply A. B. Chance heat shrink tubing number P600-1593 or TIIC number CGX-980A to overlap from a portion of the cable to section B onto section A by .64 centimeters. The heat shrink provides additional protection from moisture entering the cable and causing corrosion. Figure 2 shows a completed clamp assembly.

7.

When assembling a threaded end ferrule to the clamp. The ferrule must be inserted into the receiving boss as far as possible and the expansion washer and nut applied to the threaded end of the ferrule. For the A. B. Chance ferrule the nut must be tightened to 40.67 Newton meters to ensure proper seating of the ferrule to the receiving boss of the clamp.

8.

On some manufacturer’s clamp, there is a double screw half clamp that secures the ferrule to the clamp at the shoulder end of the ferrule. This “half clamp” is used as a spacer only and is not meant to be a current carrying part of the clamp.

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The protective ground set must be tested in accordance with Appendix C after the grounding set is competed. After the ground set has passed the required test, the ground set must be marked with the test marking as specified in Appendix C. The two approved test instruments for testing grounds are the A. B. Chance or White Safety Line ground tester.

Low Voltage (600V and below) Protective Ground Sets 1.

Purchase commercially available low voltage grounding jumpers to made a grounding set. Grounding jumpers must be #2 AWG or larger. Grounding jumpers can be field fabricated from number 2 AWG or larger insulated (yellow jacketed), extra-flexible, uncoated, stranded, copper cable having a 600 V rated TEC jacketed covering.

2.

Since low voltage grounding sets are used to prevent dangerous levels of voltage developing on the conductor or part, they are not required to be rated to carry the maximum available short circuit current.

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APPENDIX C Page 1 of 1 GROUNDING SET TEST PROCEDURE Protective grounds shall be tested annually, not later than February 1 each year, and marked with tape to identify the test year as shown in Table C-1. In addition to the resistance test, each protective ground shall be inspected to ensure tightness of connections in the clamps and ferrules and to detect physical defects. Protective grounds that are found to have loose connections or defects shall be repaired or discarded. Table C-1 Electrical Test Color Codes for Protective Grounds Extension Cords and Electrical Tools 2005 - Blue 2006 - Red 2007 - Green 2008 - Blue

2009 - Red 2010 - Green 2011 - Blue 2012 - Red

Temporary protective ground assemblies are tested to ensure that the assemblies limit the current flowing through a worker to a safe level should the ground assembly be subjected to the maximum current that the assembly is rated for the time required to clear the fault. The maximum safe current through a workers body is calculated using Dalzell’s formula: Isafe = I=tK Where Isafe = Current flowing through chest in milliamperes t = Duration of current in seconds K= A constant related to electrical shock energy K= 116 for 110 lb. worker K= 157 for 154 lb. worker K= 165 for 165 lb. worker We use a154 lb. worker and a maximum fault clearing time of 15 cycles for the safe body current calculation. t = 15/60 = .25 seconds Isafe = 157/v0.25 = 314 milliamperes To achieve a safety factor of 2, we use 157 milliamperes as the maximum allowable current through the worker. The accepted industry standard of 1000 (1) ohms as a workers body resistance is used in the calculation of the maximum voltage drop allowed across the worker in the event of a fault. Vmax = Imax x Rw

Imax = 157 ma

Vmax = .157 x 1,000

Rworker = 1,000 Ώ

= 157 Volts

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Table C-2 shows the maximum resistance allowed across the protective grounds assemblies – (clamp to clamp) for each size grounding cable. A clamp to clamp resistance equal to or less than the resistance shown in Table C-2 will limit the voltage across a shunted worker to the 157 volts. A “Micro-ohmer” or A. B. Chance Safety Ground Tester is used to test the total resistance of the ground assembly. Table C-2 Ground Cable Size

15 Cycle Ultimate Current

Max. Assembly Resistance (Micro-ohm)

#2 1/0 2/0 4/0* 250* 350*

16 kA 26 kA 33 kA 43 kA 43 kA 43 kA

9810 6040 4760 3650 3650 3650

* Limit based on clamp ratings. Any protective safety ground that has a clamp to clamp resistance greater than the resistance shown in Table C-2 should be repaired and tested, or discarded. References 1. IEEE Guide for Safety in AC Substation Grounding (ANSI/IEEE Std 80 -2000)

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Annex D Guarding Energized Electrical Equipment The following materials have been obtained from The Tennessee Valley Authority (TVA), Reference Document Procedure No. 1009, Revision 0, January 6, 2003.

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Guarding Energized Electrical Equipment 1.

Purpose

1.1.

The purpose of this procedure is to establish requirements for work with energized electrical equipment.

2.

Guarding Areas with Electrical Equipment

2.1.

Guarding of spaces and rooms in which electrical supply lines or equipment are installed shall be restricted to authorized persons under any of the following conditions:

2.2.

•

If, under normal conditions, exposed energized parts at 50 to 150 volts (to ground) are located within 2.4 meters of the ground or other working surface inside the space or room (this does not include incidental conditions, such as broken or missing light bulbs).

•

If energized parts operating at 151 to 600 volts are, under normal conditions, located within 2.4 meters of the ground or other working surface inside the space or room are guarded only by physical location.

•

If energized parts operating at more than 600 volts are located within the space or room and are not: (1) enclosed within grounded, metal-enclosed equipment whose only openings are designed so that foreign objects inserted in these openings will be deflected from the energized parts, or (2) the energized parts are installed at a height above the ground or any other working surface that provides protection at the voltage to which they are energized corresponding to the protection provided by an 8 foot height at 50 volts.

Where access is restricted to authorized personnel only, access shall be controlled in the following manner: •

The spaces or rooms shall be enclosed within fences, screens, partitions, or walls to minimize the possibility that unqualified persons will enter.

•

Signs shall be posted at each entrance to warn unqualified persons to keep out.

•

Entrances to rooms and spaces that are not under the observation of an attendant shall be kept locked.

3.

Guarding of Energized Parts

3.1.

Guarding shall be provided around all energized parts operating at more than 50 volts (to ground) without an insulated covering, unless the location of the energized parts gives sufficient clearance to minimize the possibility of accidental contact. Guidelines for clearances are contained in ANSI C2-1987 (or the edition in effect at the time of the equipment installation).

4.

Guarding of Energized Parts Within Compartments

4.1.

Except for fuse replacement or other necessary access by qualified persons, the guarding of energized parts within compartments shall be maintained during operations and maintenance functions to prevent accidental contact with energized parts and to prevent tools or other equipment from being dropped on energized parts.

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5.

When Guards Are Removed

5.1.

When guards are removed from energized equipment, barriers shall be installed around the work area to prevent personnel who are not working on the equipment from contacting energized parts.

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Annex E Jumpers The following materials have been obtained from The Tennessee Valley Authority (TVA), Reference Document Procedure No. 1010, Revision 1, November 01, 2005.

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Jumpers 1.

Purpose

1.1.

The purpose of this procedure is to establish requirements for TVA employees engaging in the use of electrical jumpers.

2.

Requirements

2.1.

Only qualified and authorized employees will troubleshoot energized control circuits.

2.2.

When using jumper cables, follow the rules and procedures listed below. •

The use of jumper cables for troubleshooting shall be strictly controlled.

•

The responsible employee shall keep a log of jumper cable use to include the circuit or component isolated by the jumper, the jumper identification number or code, the actual location of the jumper's use, the date the jumper was installed, the date it was removed, and the person responsible for attaching and removing the jumper.

2.3.

Each jumper will contain an identification number or code.

2.4.

Jumpers will be designed for the voltage and current to be imposed on them.

2.5.

Alligator clips shall have insulated covers.

2.6.

Do not use jumpers attached by means of alligator clips to bridge the secondaries of inservice energized current transformers. A positive means must be used for attaching the jumper that bridges the secondary terminals.

2.7.

Employees shall use extreme care in attaching and removing jumpers so that short circuits are not created and that the employee does not contact other energized circuits. Wear flame retardant clothing in accordance with TSP 1022, ‘Arc Flash Hazard Calculation and Required Protection” when performing this task.

2.8.

On completion of work, all equipment shall be returned to a safe condition. All enclosures such as panels, outlet covers, conduit covers, etc., shall be replaced with all bolts/screws tightened. All electrical panel doors shall be closed and latched.

2.9.

All grounds and/or jumper cables shall be removed on completion of work.

2.10.

The clearance and hold order shall be removed in accordance with the Conduct Clearance Procedure when the work has been completed and the equipment returned to a safe condition.

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Annex F Portable Electric Tools and Attachments The following materials have been obtained from The Tennessee Valley Authority (TVA), Reference Document Procedure No. 1012, Revision 3, July 15, 2006.

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Portable Electrical Tools and Attachments 1.

Purpose

1.1.

The purpose of this procedure is to establish requirements for portable electrical power tools and attachments and to ensure that portable electrical power tools and attachments are used and maintained in a safe manner.

2.

Roles and Responsibilities

2.1.

All managers, supervisors, foremen and employees are responsible for complying with the requirements of this procedure.

3.

Basic Requirements

3.1.

All portable electrical powered tools shall contain a UL label or other recognized national testing organization.

3.2.

Maximum operating speed (RPM) shall be clearly marked on the tool.

3.3.

Proper personal protective (PPE) equipment shall be worn whenever portable powered tools are used. An assessment of the work, location, and tool used should identify the proper PPE. PPE may include protective eye wear with side shields, goggles, face shields, hard hats, gloves and other body protection. Hearing protection shall be used with all electrical tools which exceed 85 dBA.

3.4.

All employees who use portable electrical powered tools shall be trained. Supplemental training shall be conducted if inspections, observations, or accident studies indicate that these tools are not being properly used or maintained. NOTE: TVAN requirement: All operations involving the use of rotating boring machines, rotating welding operations and rotating cutting operations at a TVAN facility must have a Job Safety Analysis (JSA) developed and used in performing the job.

4.

General Precautions for Portable Electrical Power Tools

4.1.

Pay close attention to body position relative to tool cutting edges.

4.2.

Never carry a tool by its service cord. Never yank the cord to disconnect it from the receptacle. Keep cords away from heat, oil, and sharp edges.

4.3.

Disconnect tools when not in use, before servicing, and when changing accessories such as blades, bits and cutters. Follow instructions in the user’s manual for lubricating and changing accessories. Do not hold a finger on the switch while carrying a plugged-in tool.

4.4.

Keep observers at a safe distance from the work area.

4.5.

Wear proper apparel. Avoid loose clothing, ties, or jewelry that can become caught in moving parts.

4.6.

Be certain the tool is in good condition and that drill bits, saw blades, etc, are securely mounted in place.

4.7.

Do not use tools without the standard guards installed.

4.8.

Check the power supply cords for damaged areas that could create electrical hazards.

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4.9.

Do not use excessive force with power tools as this can result in tool breakage, flying material, and strain/sprain injuries.

4.10.

Constant, repetitive motion with tools can result in strain/sprain injuries. Change positions, change tools or take rest breaks periodically to avoid these types of injuries.

4.11. If a tool has a “lock on” button, disengage before starting. Do not start the tool until at the work area and ready to begin. 5.

Portable Electrical Power Tools

5.1.

Double insulated portable electrical power tools should be used. Double insulated tools shall be distinctively marked to indicate that the tool is double insulated. Do not assume every tool with 2 prongs on the plug is double insulated unless it is designated on the tool. Electrical powered portable tools that are not double insulated shall have a third wire grounding conductor.

5.2.

Electrical receptacles are tested periodically (quarterly to annually) to ensure each outlet has ground circuit continuity. Receptacles should be inspected for damage and excessive dirt, coal dust, fly ash, or other foreign material.

5.3.

Each receptacle shall be the proper configuration to accommodate the plugs of portable electric tools.

5.4.

Service cords shall be inspected prior to use for damaged insulation, broken outer insulation at the plug/receptacle, and for missing ground prongs.

5.5.

Extension cords when used shall be properly sized for the load likely to be imposed (e.g., larger wire size for higher amperage tools). See TVA Safety Procedure 1004, “Extension Cords and Attachments”.

5.6.

Electrical tools should be operated within their design limitations.

5.7.

When not in use, tools shall be stored in a dry place.

5.8.

Never modify the plugs on tools or extension cords.

5.9.

Do not take or use ordinary electrical tools into potentially explosive atmospheres. Special explosion proof tools are required for this type of atmosphere.

5.10.

Route power cords around or over traffic areas and other hazards such as oil or water.

5.11.

When portable generators or vehicle-mounted generators are used to provide power for portable electrical power tools (as in outside locations where fixed electric power facilities are not available), the non-current carrying parts for equipment and the equipment grounding conductor terminals of the receptacles on the generator shall be bonded to the generator or vehicle frame.

6.

Use of Portable Electrical Power Tools in Hazardous Locations

6.1.

Portable electrical power tools capable of producing sparks, or arcing shall not be used in atmospheres containing or likely to contain explosive gases or airborne coal dusts without pre-job planning to include testing for the presence of such hazards. Such hazards, if detected, shall be eliminated prior to beginning operations. Likewise, the presence of coal and coal dust on the floors and horizontal surfaces are subject to ignition from the use of electrical tools.

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6.2.

Portable electrical power tools used in wet/damp or conductive environments, such as inside metal tanks, shall be grounded, protected by a GFCI, or be double insulated. An alternative is to use tools rated for 50 volts or less supplied through an isolating transformer with an ungrounded secondary of not over 50 volts.

7.

Switches and Controls

7.1.

Constant pressure switches are used on tools such as powered circular saws, drills, grinders, belt sanders, reciprocating saws, jig saws, and other similarly operating powered tools. They may have a lock-on control, provided that turnoff can be accomplished by a single motion of the same fingers that turn it on.

7.2.

Hand-held powered tools such as, but not limited to, platen sanders, grinders with wheels, and disc sanders with discs 5.08 centimeters in diameter or less, routers, planers, laminate trimmers, nibblers, shears, saber, scroll and jig saws with blade shanks a nominal .64 centimeter wide or less must be equipped with a positive “on-off” control.

8.

Portable Electric Drills

8.1.

Do not use bits or attachments which are not designed for a drill. Make certain the bit or attachment is far enough into the chuck and is evenly seated in the chuck.

8.2.

Secure the work in a vise, with a clamp, etc. DO NOT TRY AND HOLD ANY PIECE WHILE DRILLING. When drilling, especially in metal, center punch the hole to keep the drill from skidding on the surface.

8.3.

Do not use excessive pressure when drilling. This can cause material and drill bit breakage and possibly flying parts and material.

8.4.

Use a drill limiting device such as a drill bit stop collar when drilling into objects that contain energized electrical components to prevent contact with the energized components.

9.

Portable Electrical Power Saws

9.1.

All portable electrical powered saws will not be operated if they are not equipped with a constant pressure switch or control that will shut off the power when pressure is released. Saws shall not be used if the switch is malfunctioning.

9.2.

All portable electrical powered saws shall have the operating speed etched or otherwise permanently marked. Saws shall not be operated at a speed other than that marked on the blade.

9.3.

Keep your off-hand well clear of the blade. Do not try to support the work with your hand, knee, or any other part of your body while cutting. Properly support the work or secure it with clamps.

9.4.

Beware of kickback by keeping blades sharp and properly set, by checking the material for nails or other material, and supporting the work properly near the line of the cut. If the material sags it may cause the blade to bind.

9.5.

Keep the guard in place and working properly.

9.6.

Keep electrical cords out of the path of the saw blade.

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9.7.

Use blades that are appropriate for the material being cut and replace the blades if damaged or dull. If the material, such as wood, is wet there is a greater possibility of kickback by a saw. Do not saw wet wood.

9.8.

All portable electrical powered circular saws having a blade diameter greater than 5.08 centimeters shall not be used unless equipped with properly functioning guards above and below the base plate or shoe. The guard must function so that when the saw is withdrawn from the work, the lower guard automatically and instantly returns to a covering position. The guard must cover both the upper and lower portion of the work to the depth of the teeth except for the minimum arc required to permit the base to be tilted for bevel cuts and to allow proper retraction and contact with the work.

10.

Grinding and Cutting

10.1.

Portable electrical grinding and cutting tools shall be operated and maintained in accordance with the applicable requirements for those types of tools set forth above and the specific requirements for grinding and cutting in TVA Safety Procedure 710, “Grinding and Cutting” .

11.

Inspection / Testing of Portable Electrical Power Tools

11.1.

Each portable electrical power tool shall be visually inspected by the user prior to use.

11.2.

Formal inspections by qualified persons shall be conducted annually for the following: •

Defective/improper wiring. This would include frayed, broken, or cut outer insulation and outer insulation broken at the keeper to the plug or where the wiring enters the tool.

•

Incorrect plug configuration. All plugs shall meet NEMA configuration for applicable voltage. Crows foot plugs should not be used.

•

Inadequate or absence of continuity of equipment grounding conductor; missing, broken, or cut ground prong is cause to attach a defective equipment tag.

•

Double insulated tools shall be examined for cracked casings and grease or oil on the outer casing. Tools with cracked casings shall not be used until repaired. Tools with excessive oil or grease shall be thoroughly cleaned prior to use. Double insulated tools that have been immersed in water, mud, or other liquid shall not be used until the tool has been disassembled, cleaned, dried, and checked by a qualified person.

•

Defective or improperly configured switch.

•

Excessive accumulation of dirt, oil, grease, or other contaminants which could create a hazard or malfunction.

11.3. A record of inspections shall be maintained. The record may be maintained in any legible form as long as a unique identifier for the tool, date of inspection, and condition of the tool are noted. This record may be destroyed after one year from the inspection date. 11.4.

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Use the following annual color code banding to identify inspected portable electrical tools and attachments:

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2004

Green

2005

Blue

2006

Red

2007

Green

2008

Blue

2009

Red

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NOTE: Beginning in 2007 at TVAN sites, the color banding shall have the year labeled on the band. 11.5.

Defective tools shall be removed from service, tagged and repaired or disposed of as applicable.

11.6.

Complying tools shall be marked by a method such as taping that is well communicated to all plant/facility personnel.

12.

Training

13.

All employees who use portable electrical tools shall complete the TVA safety training course “Hand and Portable Power Tools”, ATIS 00059124.

14.

Reference

14.1.

29 Code of Federal Regulations 1910 Subpart P “Hand and Portable Powered Tools and Other Hand-Held Equipment”

14.2.

29Code of Federal Regulations 1926 Subpart I “Tools - Hand and Power”

14.3.

29Code of Federal Regulations 1910.269(I), “Electric Power Generation, Transmission, and Distribution”, Hand and Portable Power Tools”

14.4. TVA Safety Procedure 425, “Hand and Portable Power Tools Course Standard” 14.5.

TVA Safety Procedure 710, “Grinding and Cutting”

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Annex G Safe Distribution Systems The following materials have been obtained from The Tennessee Valley Authority (TVA), Reference Document Procedure No. 1014, Revision 0, January 6, 2003.

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Safe Distribution Systems 1.

Purpose

1.1.

This procedure provides requirements for personnel engaging in work with electrical distribution systems.

2.

Requirements

2.1.

Branch circuits will originate in a distribution cabinet or panel board approved for the specific environment where it is located. Covers for the cabinets or control panels shall be appropriately labeled.

2.2.

Branch circuits will include a separate equipment grounding conductor (connected to a grounding system). The grounding conductor will be equal in size and insulation to the load conductors. Bare conductors and conduit will not be used for branch circuit grounding.

2.3.

Branch circuits will be protected with overload devices of the appropriate current rating.

2.4.

Branch circuit conductors will be rated for at least 600 volts.

2.5.

Each switch, GFCI, over-current device, and receptacle will be identified or arranged in such a manner to indicate the circuit it supplies.

2.6.

Use attachment plugs or other connectors that are designed to confine electrical arcs when 300 volts or more is to be distributed.

2.7.

Junction boxes, switch panel boxes, and conduits will be fitted with covers. Covers shall remain in place except for inspection and maintenance functions.

2.8.

Bushings will be used to protect wiring entering or leaving electrical boxes.

2.9.

Power distribution centers will be used whenever extension cord runs of more than 60.96 meters are required to be used with a large number of portable electrical tools.

3.

Reference

3.1.

29 Code of Federal Regulations 1910 “Electric Power Generation, Transmission and Distribution”.

3.2.

29 Code of Federal Regulations 1910, Subpart S, Electrical

3.3.

29 Code of Federal Regulations 1926, Subpart K, Electrical

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Annex H Temporary Lighting The following materials have been obtained from The Tennessee Valley Authority (TVA), Reference Document Procedure No. 1016, Revision 0, January 6, 2003.

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Temporary Lighting Revision 1.

Purpose

1.1.

The purpose of this procedure is to establish requirements for selection and use of temporary lighting.

2.

Requirements

2.1.

Temporary lighting stringers shall not be electrically loaded beyond the manufacturer's specifications (maximum wattage) or wire size ampacity.

2.2.

Bulb sizes shall not negate the protection of the guard of the lamp holder.

2.3.

No electrical tool or appliance shall be plugged into a temporary light stringer.

2.4.

Portable lamps for routine area lighting shall be protected from accidental contact or breakage.

2.5.

Bulbs shall be protected by suitable fixtures or lamp holders with guards. A permissible alternative is to elevate the light fixture 2.13 meters above the normal working surface.

2.6.

GFCIs shall be used with all 120 volt portable lights in wet or conductive environments.

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Annex I Vehicle Operations Near Energized Lines or Equipment The following materials have been obtained from The Tennessee Valley Authority (TVA), Reference Document Procedure No. 1018, Revision 0, January 6, 2003.

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Vehicle Operations Near Energized Lines or Equipment 1.

Purpose

1.1.

This procedure establishes requirements for qualified employees performing work associated with vehicle operations near energized lines or equipment.

2.

Requirements

2.1.

Vehicles and mechanical equipment operated by a qualified employee shall be operated so that the minimum approach distances in Appendix A, Vehicle Minimum Clearance Distances for all Types of Energized Work are maintained from exposed energized lines and equipment. NOTE: The insulated portion of an aerial lift operated by a qualified employee in the lift is exempt from this requirement.

2.2.

A designated employee other than the equipment operator shall observe the approach distance to exposed lines and equipment.

2.3.

Timely warning shall be before the minimum approach distance is reached unless it is certain that the operator can accurately determine that the minimum approach distance is being maintained.

2.4.

If, during operation of vehicle equipment, the equipment could become energized, the operation shall comply with at least one of the following requirements:

2.5.

•

The energized lines exposed to contact is covered with insulating protective material that will withstand the type of contact that might be made during the operation, or

•

The equipment is insulated for the voltage involved and positioned so that its uninsulated portions cannot approach the lines or equipment any closer than the minimum approach. distances specified in the table below.

Where the vehicle could become energized in the conduct of work operations, the following measures shall be utilized: •

Use appropriate vehicle grounds identified by green color coding.

•

Bond the vehicle to the best available ground source.

•

Bond equipment together to minimize electrical potential differences.

•

When available, utilize ground mats to extend areas of equipotential.

•

Use insulating protective equipment or barricades to guard against any remaining hazardous potential differences.

2.6.

Flammable gas or liquids shall not be stored or dispensed under high-voltage lines.

2.7.

Cranes and other mobile equipment shall not be parked (when not is use) or refueled under energized high-voltage lines.

2.8.

If it is necessary in an emergency for an equipment operator to leave equipment in contact with energized high-voltage lines, the operator shall jump, not step, from the equipment to ground.

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2.9.

In generating plant environments, warning (Danger) signs shall be posted where equipment would travel beneath high-voltage lines.

2.10.

The signs shall indicate the line voltage and the line height above the ground.

3.

Definitions

3.1.

Qualified Employee (Qualified Person) One knowledgeable in the construction and operation of the electric power generation, transmission, and distribution equipment involved, along with the associated hazards. An employee must have the training required by this work practice/procedure in order to be considered a qualified employee. An employee undergoing on-the-job training and who, in the course of such training, has demonstrated an ability to perform duties safely at his or her level of training and who is under the direct supervision of a qualified person is considered to be a qualified person for the performance of those duties.

4.

Appendix

4.1.

Appendix A

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Appendix A Vehicle Minimum Clearance Distances for all Types of Energized Work VEHICLE MINIMUM CLEARANCE DISTANCE FOR ALL TYPES OF ENERGIZED WORK Distance to Vehicle Voltage in Kilovolts Phase to Phase

Phase to Ground (FT - IN)

(METERS)

Phase to Phase (FT - IN)

Avoid Contact

(METERS)

51 volts

to

300 volts

Avoid Contact

300 volts

to

1.0 KV

1-0

0.31

1-0

0.31

1.1 KV

to

15.0 KV

2-1

0.64

2-2

0.66

15.1 KV

to

36.0 KV

2-4

0.72

2-7

0.77

36.1 KV

to

46.0 KV

2-7

0.77

2-10

0.85

46.1 KV

to

72.5 KV

3-0

0.90

3-6

1.05

72.6 KV

to

121.0 KV

3-2

0.95

4-3

1.29

138 KV

to

145.0 KV

3-7

1.09

4-11

1.50

161 KV

to

169.0 KV

4-0

1.22

5-8

1.71

230 KV

to

242.0 KV

5-3

1.59

7-6

2.27

345 KV

to

362.0 KV

8-6

2.59

12-6

3.80

500 KV

to

550.0 KV

11-3

3.42

18-1

5.50

765 KV

to

800.0 KV

14-11

4.53

26-0

7.91

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Annex J Responsibilities and General Requirements for Transmission Employees The following materials have been obtained from The Tennessee Valley Authority (TVA), Reference Document Procedure No. 1101, Revision 7, July 15, 2006.

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Responsibilities and General Requirements for Transmission Employees 1.

Purpose

1.1.

The purpose of this procedure is to define individual responsibilities and general safe work requirements for transmission workers.

1.2.

In addition to the requirements provided in this procedure, the requirements defined in TVA Safety Procedure 206, “Employee Responsibilities and Rights” shall also apply.

2.

Responsibilities - Individual

2.1.

Using or being under the influence of intoxicants or drugs which might adversely influence decisions or actions while on duty is prohibited. Employees taking prescribed or other medications that could affect their ability to do their work safely shall so inform their supervisor.

2.2.

Employees shall not engage in fighting or arguing while on duty or on TVA-owned or TVA-controlled property.

2.3.

Scuffling and horseplay are prohibited.

2.4.

Employees shall not knowingly expose other persons or themselves to conditions or actions hazardous to safety or health.

2.5.

If a condition or practice is observed that is either unsafe, defective, or destructive to TVA personnel or the public, environment, or property, employees shall correct the observed problem, if possible, or report it to their supervisor.

2.6.

Employees shall know and understand the safety requirements which apply to the work they are to perform.

2.7.

Employees shall inform their supervisor of any medical constraints. Medically imposed work constraints shall be enforced by supervisors and not violated by the employee.

2.8.

An employee working alone shall plan his or her tasks to be performed. The planning shall cover the following subjects: hazards associated with the job, work procedures involved, special precautions, PPE requirements, and any system clearances that may be required.

2.9.

Existing conditions related to safety and how to control any hazards shall be determined before work on or near electric lines or equipment is started. Such conditions include the nominal voltages of lines and equipment, the presence of hazardous induced voltages, the presence of remote ground sources, the presence and condition of protective grounds and equipment grounding conductors, the condition of poles, environmental conditions relative to safety, and the locations of circuits and equipment, including power and communication lines.

2.10. Employees shall work in a position from which a slip or sudden movement will not bring their bodies into contact with exposed energized equipment parts. 2.11. Employees should be physically and mentally fit to perform their work. They have an obligation to keep their supervisor informed of physical and mental conditions that may interfere with the safe performance of their work.

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2.12. Worksites or jobsites should be kept in a safe condition. Before leaving a worksite or jobsite, employees should correct, or arrange to give warning of, any condition which might result in injury to a coworker or others unfamiliar with existing conditions. 2.13. Employees are required to attend and participate in safety meetings. 2.14.

An occupational injury should be reported to the supervisor within one hour after it occurs.

2.15. Head, back, and eye injuries require diagnosis and/or treatment by a medical provider. 2.16. A TVA employee involved in an accident or observing an accident involving TVA that results in an injury to a non-TVA person shall notify the TVA Police and his/her foreman/supervisor as soon as possible. Accidents involving serious injury or death require immediate notification by the foreman/supervisor through management channels. 2.17.

When medical care is obtained for a work-related injury/illness, the injured employee must obtain a note from the medical provider detailing guidance on the employees’ work status, i.e., “held off duty”, “constraints/restrictions”, “light duty”, or “return to regular duty”.

2.18. Medical provider notes must be coordinated with TVA Workers’ Compensation Department. Employees who receive medical care from a TVA contract medical provider will have medical constraints/restrictions documented on form TVA 1444. 3.

Supervisory Responsibilities

3.1.

Key elements in the safe performance of any work activity are the acceptance and active fulfillment of safety and health responsibilities by the individual who is charged with planning and directing the work of others. It is a prime responsibility of supervision at all levels to create and maintain a high level of safety awareness in each member of their working group. Specific supervisory responsibilities shall include, but are not limited to, the following requirements.

3.2.

Persons supervising work activities shall study, observe, and enforce the requirements in the TVA Safety Manual relating to their work activity.

3.3.

Persons supervising work activities shall ensure that all people under their direction are competent to perform their work safely.

3.4.

The supervisor shall discuss with all involved employees, the hazards associated with the job, work procedures involved, special PPE equipment, and any required system clearance. Additional discussions shall be held if significant changes occur during the course of the work.

3.5.

Conflicts of procedures, rules, practices, or other requirements shall be resolved by higher levels of supervision.

3.6.

Each first aid kit shall be readily available for use and shall be inspected frequently enough to ensure that expended items are replaced at least annually.

3.7.

Only qualified employees shall be assigned to work on or with exposed energized lines or parts of equipment or in areas containing unguarded, uninsulated, energized lines or parts

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of equipment operating at 50 volts or more. Employees in training and under the direct supervision of a qualified employee may also perform work in these areas. 3.8.

Except as provided in the Note below, at least two employees shall be present when exposed to any unguarded, uninsulated power system equipment having the electrical potential of more than 600 volts. Note: The above does not apply to the following operations. •

Routine switching of circuits under conditions that allow this work to be performed safely.

•

Work performed with live-line tools, if the employee is positioned so that he or she is neither within reach of, nor otherwise exposed to, contact with energized parts.

•

Emergency repairs to the extent necessary to safeguard the general public.

3.9.

Persons supervising work activities should encourage proper attitudes, instruct members of their work unit in safe work techniques, and provide and maintain safe working conditions for employees under their supervision.

3.10.

Persons supervising work activities should inform employees of safety requirements which apply to the work and inform them of any recognized hazards, precautions, or special regulations which may affect safe job completion. Special consideration should be given to new employees or those unfamiliar with the work to aid them in developing safe working habits.

3.11.

Pre-job briefings shall be conducted daily before beginning work.

3.12.

Form TVA 17566, Manager’s Checklist for Energized Work, shall be completed, signed and dated by the appropriate manager or his/her designated representative before a crew begins any energized work, as described by procedure 1109, requirement 2.3. Completed checklists shall be retained for 90 days.

3.13. When determining whether work is available that can accommodate a worker’s medical constraint/restriction, Supervisors shall consult with management before employees are returned to work or sent home. 4.

Protection of the Public

4.1.

Members of the public may request information on safe approach distances to power lines. Information on non-utility work minimum approach distances to power lines is shown in TVA Safety Procedure 1108.

4.2.

The public should not be permitted in locations where work activity may endanger them.

4.3.

The public should be protected from the hazards of transmission line construction at water crossings.

4.4.

If worksites or jobsites must be left unattended before completion of a job, employees should correct or give warning of any condition which might result in injury to a member of the public.

4.5.

When work is being conducted along public streets or highways, pedestrian and vehicular traffic should be warned by signs, flags, or flashing lights by day, and lights, flares,

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luminous tape barriers, or flashing lights by night. When necessary, persons wearing reflective vests should be assigned to signal traffic of the hazard created or divert traffic around the hazard or work activity. Employees flagging traffic should be properly trained. 5.

Motor Vehicle Safety

5.1.

Obedience to laws will not be enough to prevent accidents. Alertness, common sense, and courtesy will improve your chances of avoiding accidents. Safety, in your work or when driving a vehicle, is a state of mind. To extend courtesy to all drivers and pedestrians is the best way to ensure your own safety. By your courteous attitude, you will properly represent TVA. Drive defensively.

5.2.

Work vehicles include pick-up trucks (4- and 2-wheel drive), cargo work vans, station wagons, jeeps, trailers, mobile crane trucks, truck mounted aerial lifts and tractors. Vehicle/manufacturers’ rate vehicles using a Gross Vehicle Weight Rating (GVWR) which is the MAXIMUM WEIGHT for a single vehicle including its load. The GVWR is determined by factors such as the power train, suspension, axles, brakes, and tires. Exceeding the GVWR is very dangerous and will affect the steering and braking of the vehicle. By knowing the weight of your vehicle and its GVWR, the safe loading capacity for the vehicle can be determined.

5.3.

When loading a vehicle, the cargo should remain as low as possible. Heavy loads carried on truck racks will raise the center of gravity of the vehicle and will cause the vehicle to become unstable in curves or when swerving to avoid a hazard.

5.4.

Tires also have a load rating. The proper load-rated tire should be installed on the vehicle to safely handle the loads being transported.

5.5.

Vehicles shall not be loaded past their GVWR.

5.6.

Heavy cargo loads (such as steel poles) shall not be hauled on truck racks.

5.7.

The aggregate static Working Load Limit (WLL) of tie-down assemblies used to secure an article against movement during transport shall be equal to at least ½ (0.5) times the weight of the article. An even number of chains shall be used. The WLL shall be determined either from the charts in the Useful Information Section 16 or the tags or labels attached to the tie-down assembly. For example, divide weight of load to be hauled by 2 and divide that number by the strength of the chain from chart or tag. This will give the number of chains required: Load = 33,566 kilograms: 33,566 ÷ 2 = 16,783 kilograms Strength of chain from chart: 3,221 kilograms and 16,783 ÷ 3,221 = 5.21, therefore, 6 chains required

5.8.

When loading a vehicle, the cargo should be centered and as low as possible.

5.9.

Vehicles should not be loaded past the axle weight rating or the tire load rating.

5.10.

Drivers of vehicles on TVA business are required to hold valid state drivers licenses and are subject to all traffic laws and ordinances. Employees who operate vehicles or equipment requiring a Commercial Drivers License (CDL) must obtain and maintain a

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current and valid CDL including the required Medical Examination S-05. Suspension or withdrawal of the license must be reported to the supervisor. Reference TVA Safety Procedure 610, Motor Vehicle Operations”, paragraph 7.8 for additional CDL maintenance requirements. 5.11.

If it is possible for any part of a vehicle to contact energized equipment or conductors, the body of the vehicle shall be grounded. Be sure that radio and telephone antennas have sufficient clearance.

5.12. Vehicles stopped on roadways shall be properly identified by approved markers and/or warning light. 5.13.

When vehicles are in motion, operators and passengers shall use seat belts. Drivers shall ensure that all passengers’ seat belts are operational and fastened prior to putting the vehicle in motion.

5.14.

Get on or off vehicles only after they have come to a complete stop.

5.15.

When a vehicle is parked, the driver shall set the brake or otherwise secure the vehicle from undesirable movement.

5.16.

When a trailer is disconnected from a vehicle, it shall be secured to prevent undesirable movement.

5.17.

Radio transmitters and cellular phones shall not be operated in the vicinity of blasting operations or near employees with identified electronic pacemakers or medical equipment.

5.18.

Smoking, welding, open flames, or other sources of ignition shall not be permitted within 15.2m of any refueling activity.

5.19. Headlights shall be used when fog is encountered or when driving in the rain. (Parking lights should never be used in lieu of headlights while the vehicle is moving.) 5.20.

No vehicular equipment having an obstructed view to the rear may be operated on offhighway jobsites where any employee is exposed to the hazards created by the moving vehicle, unless: •

The vehicle has a reverse signal alarm audible above the surrounding noise level, or

•

The vehicle is backed up only when a designated employee signals that it is safe to do so.

5.21.

Immediately before backing a vehicle, the driver shall determine that the space is clear.

5.22.

When possible, vehicles shall be parked such that backing will not be required when the vehicle is moved. Where possible, vehicles should be driven through “straight” parking spaces and parked to exit by driving forward. When a “drive-through” space is not available, the vehicle should be backed into the “straight” parking space.

5.23. It is the driver’s responsibility to back his or her vehicle safely. When another employee is available, he or she should assist the driver by guiding or observing during the backing of the vehicle.

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5.24. When employees are being transported, the responsible supervisor or driver should verify that the vehicle is not overcrowded, adequate seating is provided, and passengers remain seated while the vehicle is in motion. 5.25.

Tools and other injury-producing objects carried inside vehicles should be secured or a screen installed between the cargo and vehicle occupants. Fuel containers should not be carried inside the passenger/driver compartment.

5.26.

A-frames or collapsible booms mounted on trucks and tractors should normally be disassembled before being transported over public roads and highways. However, if an A-frame is to be used immediately at another location and highway travel is kept to a minimum, it is permissible to transport the assembled A-frame if it is lowered to a safe position and the stiff leg secured. The path should be examined for safe clearance.

5.27.

Check overhead clearance and use extreme caution when driving into or out of any building or area where visibility is limited.

5.28.

Keep vehicle in gear when moving downgrade.

5.29.

The driver should be alert for equipment defects. If a defect causes any unsafe condition or impairs safe operation of the equipment, operation should be suspended until the defect has been corrected. Any employee noting such defects should take appropriate action to secure replacement or repair according to applicable procedures.

5.30.

Equipment or vehicle engines should be shut off during refueling.

5.31.

Drivers should not indicate (telegraph) the intentions of other drivers through the use of turn indicators or hand signals.

5.32.

When filling portable metal gasoline cans, they should be removed from the bed of the vehicle to avoid possible static discharge.

5.33.

Drivers of vehicles on official TVA business, shall maintain a minimum safe following/stopping distance between their vehicle and the vehicle ahead equal to 2 seconds. This rule (2 second rule) is applicable as a minimum safe driving distance when following another vehicle under good driving conditions. Under poor driving conditions (weather or heavy traffic), add additional seconds to the 2 second rule, as appropriate.

6.

General Requirements

6.1.

Oil-soaked rags and flammable liquids shall be stored in approved noncombustible containers.

6.2.

Emergency exits and fire escapes shall be kept clear of obstructions that would prevent use for an emergency.

6.3.

Sufficient illumination shall be provided to enable employees to perform their work safely.

6.4.

Supervisors should assign areas of housekeeping responsibility to individuals and allot time for housekeeping.

6.5.

Glass containers are prohibited at construction worksites unless they are protected from breakage.

6.6.

The operating area or compartment of all vehicles should be kept free of litter and debris.

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6.7.

Supervisors shall make regular inspections and enforce housekeeping requirements.

6.8.

Tools, containers, and materials should not be placed where they may be tripping hazards or where they may fall.

6.9.

All scrap, waste materials, and rubbish should be removed from the immediate work area as the work progresses.

6.10. Disposal of waste material or debris should comply with TVA policy and local fire and environmental regulations. 7.

Fire Prevention and Suppression

7.1.

A fire needs fuel, oxygen, and heat. Remove any one of these to extinguish it. Fires are divided into three classes according to the types of combustible materials involved. Each class requires a different fire fighting technique.

7.2.

Class A fires are fires in ordinary materials, such as wood, paper, excelsior, rags, and rubbish. To extinguish them, use water or solutions containing a large percentage of water.

7.3.

Class B fires are fires in flammable liquids, such as gasoline, oil, and grease. The blanketing or smothering action of dry chemicals or carbon dioxide is effective in extinguishing fires of this class. Solid streams of water are likely to spread the fire; but, under certain circumstances, water-fog nozzles prove effective.

7.4.

Class C fires are fires in or near energized electrical equipment. A nonconductive extinguishing agent, such as carbon dioxide or dry chemicals, is effective in controlling these fires. A solid stream of water should not be used on fires involving energized electrical equipment. However, water from a fog nozzle can sometimes be used on fires in electrical equipment, such as transformers.

7.5.

Signs prohibiting smoking and open flames shall be strictly observed.

7.6.

Dirty clothing, rags, or other combustible material shall not be allowed to accumulate in lockers and tool storage areas.

7.7.

Gasoline and other highly volatile, flammable liquids shall not be used to start fires.

7.8.

Fire protection equipment shall be kept at its designated location except for actual use or maintenance.

7.9.

Liquids which are highly volatile and flammable shall be clearly labeled and not be stored, transported, or left unattended in open containers.

7.10.

Whenever there is danger of static electrical buildup and discharge in the presence of flammable, volatile liquids, or gases, all apparatus and containers shall be bonded together and grounded.

7.11.

Fire-extinguishing equipment shall be inspected monthly.

7.12. An employee should not leave open fires unattended. 7.13.

When welding or cutting operations are performed at elevated positions, precautions should be taken to prevent hot metal from falling onto people or into combustible materials.

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7.14. Welding or cutting should not be done near exposed, flammable liquids, or gases. Flammable dust in the work area should be removed or shielded to prevent ignition. 7.15.

Where flammable material cannot be removed from exposure to welding or cutting sparks, it should be protected by a shield of non-combustible or fire-resistant material. Suitable fire-extinguishing equipment should be readily available.

7.16.

Each employee should be familiar with both the location and operation of all fire protective equipment and systems in the vicinity of their work area.

7.17. Each employee should know how to turn in a fire alarm and what to do in case of fire. 7.18. An appropriate fire extinguisher should be installed in TVA work vehicles. 8.

Office Safety

8.1.

Office workers are subject to many of the same types of accidents that occur in production and maintenance areas. Some of the most frequent types of office accidents are falls, strains, cuts, and electrical shocks. To avoid injuries in offices as well as in plant or field areas, all employees should be alert for potential hazards and should conscientiously strive to develop good safety habits.

8.2.

When climbing, use an approved step stool or ladder.

8.3.

Any electrical defects in cords or machines should be promptly reported and repaired.

8.4.

Portable heaters shall not be placed close to combustible or flammable materials.

8.5.

Walk, do not run. Always use handrails when ascending or descending stairways.

8.6.

Extension cords should not be strung across aisles or walkways where people may trip or fall over them.

8.7.

Broken glass or other sharp objects should not be placed in wastebaskets unless wrapped or properly protected.

8.8.

Material or equipment should not be stored or placed where it could fall.

8.9.

Serious strains often result from improper handling of boxes and bundles of office supplies, ledgers, portable filing cases, and office machines. Lifting should be done with back erect, using the more powerful leg muscles. See TVA Safety Procedure 1107, Manual Material Handling for Transmission Workers.

8.10.

Opening loaded file drawers, particularly more than one at a time, may tip over a cabinet. Where several tiers of cabinets are used at one location, they should be fastened together. Single cabinets should be secured from tip-over. Do not leave desk drawers, file drawers, or desk slides open.

8.11. Keep fingers away from the cutting edge of paper cutters. The cutter blade should be left in a closed position when not in use. 8.12. Doors should be opened slowly to avoid striking anyone on the other side.

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9.

Personal Protective Equipment (PPE) and Clothing

9.1.

PPE shall be worn when its use is deemed necessary by the supervisor. PPE and clothing provided by TVA shall not be altered. When at a power plant, the plant’s requirements for PPE must also be met.

9.2.

Eye and Face Protection

9.3.

A recognized eye hazard is one that presents a reasonable probability of injury that can be prevented by eye protective equipment such as welding or cutting, electrical arcs, brush chippers, grinding, buffing, or wire brushing with power tools, handling hazardous chemicals, dusty operations, or other similar activities. Contact lenses do not provide eye protection in the industrial sense and may increase the hazard to the wearer’s eyes in some situations. Additional requirements for operations requiring eye and face protection may be found in the TVA Safety Procedure 304, Eye and Face Protection.

9.4.

Appropriate industrial eye protection shall be worn by employees whenever they are exposed to a recognized eye hazard.

9.5.

Safety eyewear with sideshields shall be worn in all construction areas, maintenance areas, and during field surveying activities. Safety eyewear is not required in vehicles, office areas, or during safety meetings.

9.6.

Employees shall wear appropriate safety eyewear when performing certain operations such as brush chipping, welding, torch cutting, grinding, buffing, wire brushing, sawing, drilling, installing grounds on high-voltage conductors or equipment, handling chemicals, or working in dusty environments.

9.7.

When the work environment entails exposure to fumes, vapors, splashes, intense heat, molten metals, or highly particulate atmospheres, contact lenses should not be used.

9.8.

Hearing Protection

9.9.

Employees exposed to hearing hazards shall wear appropriate hearing protectors.

9.10.

Knee Protection

9.11. Padding should be used when work requires kneeling on a hard surface and placing body weight directly on a bent knee(s). 9.12.

Foot Protection

9.13.

Employees shall not wear casual or athletic type footwear in a construction work environment.

9.14.

Employees should wear footwear appropriate to their occupation and the hazards of their job.

9.15.

Head Protection

9.16. Approved head protection issued by TVA shall be worn by all persons when in areas where falling objects or other hazards may cause a head injury and in any areas designated by the supervisor.

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Employees with hair length that could present a hazardous condition when working around reciprocating or revolving equipment or machinery shall contain hair in a net or other suitable means to prevent entanglement.

9.18. Safety headgear that exhibits cracks or other signs of deterioration shall be replaced by a new approved headgear. 9.19.

Skin Protection

9.20. Skin should be protected from contact with harmful chemicals. 9.21. Respiratory Protection 9.22.

Specific requirements for respiratory protection are contained in the “Respirator Program” document. The following Rules shall apply in any case of respirator use.

9.23. When respirators are required for a particular work activity, they shall be used. 9.24. Those using respirators shall follow the manufacturer’s instructions or the specific instructions of supervision. 9.25.

Work requiring respirators shall not be done when conditions prevent a good face seal. Such conditions may be a beard, sideburns, a skull cap protruding under the face piece, or temple pieces on glasses.

9.26.

A medical examination (S-3) shall be given to employees who are required to wear a negative pressure respirator.

9.27. Employees shall be fit-tested before being issued a respirator to determine the proper size needed and adequate fit. 9.28.

Clothing

9.29.

Employees shall wear fire resistant clothing when they are within 1.2 meters of any area where there is the possibility of exposure to the hazards of electrical arc or flashover and when performing switching. Fire resistant clothing or switching jackets will be provided to employees whose work assignments potentially expose them to this environment. An electrical potential of 480 or more volts (ac) with a fault current capacity of 1000 or more amperes is considered capable of producing a flashover or arc hazardous to employees who are within 1.2 meters of it when it occurs.

9.30.

When work is performed within reaching distance of exposed energized parts of equipment, each employee shall remove or render nonconductive all exposed conductive articles, such as key or watch chains, rings, or wrist watches or bands, unless such articles do not increase the hazards associated with contacting the energized parts.

9.31.

Protective chaps shall be worn by chain saw operators when they are operating a chain saw except when working off the ground.

9.32.

Hand protection shall be worn when performing any activity which could puncture, cut, burn, pinch, or otherwise injure the hand, such as: handling poles; steel; wire or cable; barrels; drums; cylinders; heavy materials; ropes; handlines; climbing poles, structures, or ladders; or assembling poles or structures.

9.33.

Rings, dangling jewelry, and similar items that constitute a hazard shall not be worn while operating or working around moving machinery. When performing construction or

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maintenance activities where there is the risk of finger injury, rings shall be removed or gloves worn. 9.34.

Shirt sleeves should be no shorter than tee shirt length or at least 7.62 centimeters in length on rights-of-way or in other industrial environments. Shirts should not be removed.

9.35. Lifejackets 9.36.

Whenever an employee may be pulled or pushed or may fall into water where the danger of drowning exists, the employee shall use a U.S. Coast Guard approved personal flotation device properly fastened or secured.

9.37. Each personal flotation device shall be maintained in safe condition and inspected before each use to ensure that it does not have rot, mildew, water saturation, and/or any other condition that could render the device unsuitable for use. 9.38.

Fall Protection Systems

9.39.

Any lifeline, body belt, safety belt, body harness, or lanyard subjected to in-service loading shall be immediately removed from service and shall not be used again for employee safeguarding.

9.40.

All body belts, safety straps, safety belts, lanyards, lifelines, and body harnesses shall be inspected annually (by February 1) and marked to indicate the year tested as outlined in TVA Safety Procedure 1609. In addition, these fall protection systems shall be inspected before use each day to determine that the equipment is in safe working condition. A 10.16 centimeter space in the center of the back on all body belts shall be free of tool loops, bolt bags, or any other attachments.

9.41.

Lifelines shall be protected against being cut or abraded.

9.42.

Personal fall arrest systems shall be rigged such that an employee can neither free fall more than 1.8 meters or contact any lower level.

9.43. If vertical lifelines or droplines are used, only one employee shall be attached to any one lifeline. 9.44. Snap hooks shall not be connected to loops made in webbing-type lanyards nor to each other. 9.45.

Safety lanyards used with a body harness shall be of the decelerating type.

9.46. Safety strap and lanyard snap hooks shall be of the locking type. 10.

Reporting of Accidents, Injuries, or Near- Miss Incidents

10.1.

Injuries shall be reported promptly to the supervisor. Near-miss incidents that have the potential for causing serious injury or property damage shall be reported. Injuries to nonemployees as a result of TVA activities shall be promptly reported. The scene of any serious accident or near-miss incident shall be left as near undisturbed as possible pending investigation.

10.2.

All accidents involving rented, leased, or private vehicles being used for official TVA business shall be reported promptly. Employees shall comply with all applicable local

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and state regulations and make an immediate report of vehicular accidents to their supervisor and TVA Police.

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Annex K Transmission/Substation/Telecommunication The following materials have been obtained from The Tennessee Valley Authority (TVA): Manual Material Handling for Transmission Workers Reference Document Procedure No. 1108, Revision 1, January 27, 2006. Protective Grounding Reference Document Procedure No. 1109, Revision 5, November 01, 2005. Minimum Clearance Distance for Energized Work Reference Document Procedure No. 1110, Revision 2, January 27, 2006. General Requirements for Transmission, Substation and Telecommunication Reference Document Procedure No. 1201, Revision 3, January 27, 2006. Electrical Testing Reference Document Procedure No. 1202, Revision 1, November 01, 2005. Energized Equipment Maintenance Reference Document Procedure No. 1203, Revision 1, January 27, 2006. Helicopter Operations for Transmission Work Reference Document Procedure No. 1204, Revision 1, April 16, 2004. Insulator Cleaning on Energized Circuits and Equipment Reference Document Procedure No. 1205, Revision 1, July 15, 2006. Live-Line Work Reference Document Procedure No. 1206, Revision 1, July 15, 2006. Stringing and Removing Conductors Reference Document Procedure No. 1207, Revision 2, July 15, 2006. Transmission Line Work Reference Document Procedure No. 1208, Revision 3, July 15, 2006. Right of Way Clearing and Grounds Maintenance Reference Document Procedure No. 1209, Revision 2, July 15, 2006.

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Manual Material Handling for Transmission Workers 1.0

Purpose

1.1.

The purpose of this procedure is to establish requirements for material handling for transmission workers.

1.2.

Topics include: •

Manual Material Handling

•

Material Handling Equipment

•

Hand Trucks

•

Forklift Trucks

•

Work Platforms on Forklift Trucks

•

Hoists

•

Compressed-Gas Cylinders

2.0

Manual Material Handling

2.1.

Injuries from manual material handling usually result from unsafe working habits, such as improperly lifting, carrying a load that is too heavy, gripping the load in an unsafe manner, and failing to use protective equipment. Setting an object down is essentially the reverse of lifting. See TVA Safety Manual, Useful Information 1607, “Rigging/Lifting”.

2.2.

If employees are unable to see over or around the load they are handling, an observer shall be used to give directions.

2.3.

Nails or staples shall be removed from boxes, kegs, or crates before removal of material. When pulling is not practical, nails or staples shall be completely bent down.

2.4.

Material shall be properly stacked or secured to ensure stability.

2.5.

When two or more employees are lifting material, one person shall be designated to direct and coordinate the lift.

2.6.

Approved PPE shall be used when handling hazardous materials.

2.7.

Gloves or other hand protection shall be worn when gripping loads with sharp edges or corners.

2.8.

Before gripping an object to make a lift, first consider the probable weight and dimensions involved.

2.9.

Inspect material for slivers, jagged edges, burrs, and rough or slippery surfaces.

2.10.

Get a firm grip on the object.

2.11.

Keep fingers away from pinch points, especially when setting material down.

2.12.

Keep hands free of oil and grease.

2.13.

Wipe off greasy, wet, slippery, or dirty objects before you handle them.

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2.14.

When handling lumber, pipe or other long objects, keep the hands away from the ends of the object to prevent them from being pinched.

2.15.

A wide range of hand or hand-operated tools, kits, and other devices can be used to handle materials. Each tool, jig or other device should be kept in good repair and should be used only for the job for which it was designed.

2.16.

Do not lift more than you can handle comfortably. If necessary, request help.

2.17.

Safe lifting techniques should be used for manual material handling. The following should be considered prior to lifting any load manually: size, weight, shape of load, feet, and body position. Lift with your legs, keep your back straight, ensure firm grip and footing, and maintain adequate control over and around load. Exertion should be performed while exhaling.

2.18.

Avoid twisting the body when handling material.

2.19. Straighten your legs to lift the object and, at the same time, swing your back into a vertical position. 3.0

Material Handling Equipment

3.1.

Rigging used in mechanical lifting shall be of adequate capacity and support for the intended load. Rigging equipment shall be inspected before each use, and any found defective shall be tagged defective and not used until repaired, or it shall be discarded.

3.2.

1.27 centimeters or larger hand line shall be used as a load line when raising or lowering equipment or materials to or from an elevation.

3.3.

Tag lines shall be used to control loads being handled by hoisting equipment in areas where other workers are present.

3.4.

Mechanical equipment, when not in use or left unattended, shall have blades and/or buckets on the ground, booms racked or on the ground, and ignition switches locked or the equipment reasonably disabled to prevent starting by unauthorized personnel.

3.5.

Seat belts shall be installed, maintained, and worn on equipment with rollover protection.

3.6.

Load-hook latches should be used and maintained in an operable condition.

4.0

Hand Trucks

4.1.

Keep the center of gravity of the load as low as possible.

4.2.

Place the load well forward so that the weight will be carried by the axle and not by the handles of the truck.

4.3.

Place the load so that it will not slip, shift, or fall off. Load only to a height which will allow a clear view ahead.

4.4.

Let the truck carry the load. The operator should only maintain its balance and provide the motive power.

4.5.

When going up or down an incline, keep the truck below you.

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4.6.

Move the truck at a safe speed. Do not run. Keep the truck constantly under control. The operator should have an unobstructed view.

4.7.

A four wheel truck should be loaded evenly to prevent tipping.

5.0

Forklift Trucks

5.1.

Only certified operators shall operate forklifts.

5.2.

Internal combustion engines shall be turned off while refueling and shall be refueled only in open or well-ventilated areas.

5.3.

Overhead clearances shall always be observed.

5.4.

Forklifts shall not be left unattended unless the forks are on the floor or ground.

5.5.

Only the driver shall be allowed to ride a forklift during transit.

5.6.

If you must leave the equipment unattended, shut off the power, neutralize the controls, and set the brakes. Unattended is when the operator is 7.6 meters or more away from the lift which remains in his view; or whenever the operator leaves the lift and it is not in his view, wheels shall be blocked if the lift is on an incline.

5.7.

Keep your legs and feet inside the guard or operating station of the forklift.

5.8.

Observe traffic rules: Operate at a safe speed, keep to the right whenever possible, slow down or stop at intersections, and use the horn at blind corners.

5.9.

Travel a forklift with the forks or the pallet about 10.16 centimeters off the floor. On a downgrade, the loaded forklift should go down with the load last; on an upgrade, with the load first.

5.10. Keep the forklift under control so that an emergency stop can be made in the clear distance ahead. 5.11.

Do not use the reverse control on electric forklifts for braking.

5.12.

Travel slowly when crossing a bridge plate.

5.13.

Cross railroad tracks diagonally whenever possible.

5.14. When operating in close quarters, keep your hands where they cannot be pinched between the steering control and projecting stationary objects. 6.0

Work Platforms on Forklift Trucks

6.1.

Forklifts shall be operated only by certified persons.

6.2.

Before work is begun aloft near energized equipment, the forklift shall be properly grounded.

6.3.

Operators and employees working aloft near energized equipment shall know minimum clearance distances and the location of energized equipment before starting work.

6.4.

The work platform shall be firmly secured to the forks.

6.5.

The platform shall have guardrails and toe-boards to prevent falls, and a floor of nonskid material.

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6.6.

The forklift shall not be moved with employees on the platform.

6.7.

Because the weight of the forklift is such that miring is a problem, the path to be taken should be carefully chosen to avoid soft ground. A heavy plywood sheet or board may be placed under the wheels to distribute the load over a greater area.

7.0

Hoists

7.1.

A hoist shall never be loaded beyond its rated capacity.

7.2.

Do not use a known defective hoist.

7.3.

Never wrap the hoist, load chain, or cable around the load.

7.4.

Seat the load securely in the hook throat.

7.5.

Do not operate with a twisted, kinked, or damaged chain.

7.6.

A sleeve or "cheater" shall not be used on the handle of hand-operated hoists.

7.7.

The chain should be kept clean, lubricated, and free of rust.

7.8.

Stand clear of all loads being lifted.

8.0

Compressed Gas Cylinders

8.1.

Compressed gases are received from vendors in metal cylinders at very high pressure. If a cylinder ruptures or a cylinder valve assembly is broken off, the sudden release of this pressure would produce a rocket effect and propel the cylinder with enormous force. This rocket effect has been known to knock down walls, wreck buildings, and more tragically, maim or kill people.

8.2.

Do not repair, alter, abandon, or destroy compressed-gas cylinders. Defective cylinders shall be tagged and returned to the vendor.

8.3.

Valve protection caps shall always be in place, hand tight, except when cylinders are connected for use.

8.4.

Do not force connections or tamper with the safety relief devices or valves on compressed-gas cylinders.

8.5.

Compressed-gas cylinders, whether full or empty, shall be stored in an upright position and properly secured. This does not apply to SF6 gas cylinders.

8.6.

Compressed-gas cylinders shall be stored in a well-ventilated area.

8.7.

Compressed-gas cylinders shall not be rolled, lifted by the valve cap or valve, dropped, jarred, or exposed to extreme temperatures.

8.8.

Compressed-gas cylinders shall not be placed where they might accidentally become part of an electrical circuit.

8.9.

Oxygen cylinders in storage shall be separated from fuel gas cylinders or highly combustible materials (such as oil or grease) by a distance of 6.1 meters or a fireretardant wall.

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8.10.

Oil, grease, or similar materials shall not be allowed to come into contact with any valve, fitting, regulator, or gauge of oxygen cylinders.

8.11.

Acetylene cylinders shall be used, transported, or stored in a vertical position.

8.12.

Compressed gas cylinders transported by crane, hoist, or derrick shall be handled in suitable cradles, nets, or boxes and shall not be lifted by magnet or slings, unless the slings are designed and constructed to prevent accidental release of the cylinder.

8.13.

Compressed gas cylinders in portable service should be conveyed by suitable trucks (hand) or temporarily attached lifting handles (commercially manufactured).

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Protective Grounding 1.

Purpose

1.1.

The purpose of this procedure is to establish requirements for the installation and maintenance of electrical safety grounds.

2.

Installation and Maintenance of Safety Grounds - General

2.1

Safety grounds are used for the protection of employees working on equipment. Safety grounds limit voltages between points at the work site and shunt currents around the employees. These voltages and currents arise from several sources such as: •

ground rise potentials from grounds remote to the work site,

•

electro-magnetically induced energy,

•

electro-statically induced energy,

•

inadvertent contact with other energized circuits,

•

station service back-feeds,

•

instrument transformer back-feeds,

•

test equipment back-feeds, or

•

inadvertent energization of the normal power circuit.

Good grounding procedures which control induced voltage are increasingly important as lines are constructed closer together. The following grounding requirements do not cover every grounding application; but if the principles given are applied with discretion and judgment, safe working conditions will result. 2.2.

Safety grounds do not protect employees from lightning strikes near the work location. When lightning is a threat, work must be suspended.

2.3.

ALL ELECTRICAL CIRCUITS AND EQUIPMENT SHALL BE TREATED AS ENERGIZED UNLESS PROPERLY GROUNDED. THIS INCLUDES OVERHEAD GROUND WIRES.

2.4.

Temporary safety grounds shall be placed at such locations and arranged in such a manner as to prevent each employee from being exposed to hazardous differences in electrical potential, i.e., worksite grounding. This means that an equipotential work zone for the exposed employees shall be established unless alternate grounding methods are approved by management with appropriate consultation with safety, technical, or appropriate engineering and design staff. Employees are not considered "exposed to hazardous difference in electrical potential" when working on lines or equipment that can NOT be energized from ANY source and is adequately grounded to remove any induced voltage.

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NOTE: Prior to installing temporary protective grounds at Fossil Power Group (FPG) plants, a written plan detailing where the temporary protective grounds will be placed must be submitted and approved by the manager responsible for performing the work and the manager at the plant responsible for the grounding. This plan must include a Job Safety Analysis (JSA) prepared in accordance with TVA Standard Programs and Processes (SSP) 18.005, “Plan Jobs Safely,” a generation sensitive activity sheet (if applicable), electrical diagrams, and a description of the work to be accomplished. A pre-job safety briefing (SSP 18.005) on the installation of the temporary protective grounds must be conducted with all involved personnel. 2.5.

Grounding of only one phase for establishing an equipotential work zone is allowable only if 3-phase grounds are also in place and safe work clearance to adjacent phases are maintained.

2.6.

Only approved grounding devices shall be used. Safety grounds shall be tested annually (by February 1) and marked to indicate the year tested as outlined in TVA Safety Procedure 1504, Safety Grounds and Field Test Procedures for Safety Grounds, and TVA Safety Procedure 1609, Color Codes for Electrical Tests for Hotsticks, Insulated Measuring Sticks, Safety Grounds, Extension Cords and Electric Tools.

2.7.

In all cases, the person holding the clearance shall be responsible for placing and removing the safety grounds and informing everyone involved of the limits of the clearance.

2.8.

A voltage detection device shall be used prior to placing of safety grounds to detect nominal potentials. Buzzing with a hotstick is acceptable only if the voltage detection device is inoperable or in emergency situations. This requirement does not apply to gasinsulated switchgear (see paragraph 5 of this procedure, Gas-Insulated Switchgear Grounding).

2.9.

When attaching grounds, fasten the ground end first. Use an approved insulated tool to attach the other end.

2.10.

When attaching grounds to flat surfaces, the set screw shall be tightened.

2.11.

When removing grounds, remove the line or equipment connection first with an approved insulated tool (never use hands) and then break the ground connection.

2.12.

Two or more grounds shall not be connected in series to make a longer safety ground.

2.13.

In no case shall a power circuit breaker be used for extending a grounding circuit.

2.14.

All safety grounds and ground sticks shall be visually inspected before each use.

2.15.

Protective grounding equipment shall be capable of conducting the maximum fault current that could flow at the point of grounding for the time necessary to clear the fault (See TVA Safety Procedures 1503, 1504, 1505, 1506.

2.16.

Any safety ground known to have experienced fault currents from nominally energized equipment or lightning stroke current shall be removed from service and discarded.

2.17.

The appropriate clamp shall be used when connecting to bus, conductor, structures, etc., and shall be sized to meet or exceed the current carrying capability of the safety ground conductor.

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2.18.

TVA employees working on non-TVA equipment, facilities, or systems SHALL adhere to the TVA safety grounding requirements.

2.19.

The standard ground conductors for transmission line and substation grounding shall be 1/0, 2/0, or 4/0 or 250 MCM extra flexible copper conductor with yellow thermoplastic elastomer (TPE). The purpose of the yellow thermoplastic elastomer (TPE) is to protect the strands of the ground cable from abrasion and mechanical damage and is not considered as insulation for the purpose of personnel protection.

2.20.

After repair or replacement of conductor or clamps, each safety ground shall be tested and marked with color tape as designated in TVA Safety Procedures 1504 and 1609.

2.21.

The grounding surface shall be clean and free of rust, corrosion, paint, or other insulating coatings.

2.22.

Employees on the ground should avoid unnecessary contact or work within 3 meters of any structure, temporary ground rod, or equipment connected to the worksite safety grounding system, since a rise in potential above the surrounding terrain may occur. If employees must perform work within this 3-meter zone, they should not stay any longer than is required to perform their work.

2.23.

All ground sticks should be tested at regular intervals (see test criteria in TVA Safety Procedure 1102, requirements 8.1 and 8.8).

2.24.

Safety grounds should be kept as short as reasonably possible and installed so as to hang as straight as possible with no folds or sharp bends. Folds or bends increase the mechanical hazard and impedance should fault current result from unintended energization.

2.25.

Only one subconductor in a bundled phase conductor needs to be grounded.

2.26.

When working on de-energized circuits, all phases of lines or apparatus should be grounded.

2.27. When applying grounds, always ground the nearest conductor, bus, or apparatus first then proceed outward and upward. Reverse this procedure when removing grounds. Remove the farthest safety ground first. 2.28.

Workers should stand well below and not directly under the parts to be grounded in order to keep their bodies away from any arc that may occur when the ground device is applied. The employee shall not hold the ground conductor in his hand or next to his body while installing.

2.29.

Be aware of capacitive discharge from apparatus when grounding.

2.30. An air break switch can be used to extend a ground circuit but only if it has been closed, tagged, and locked. When an air break switch is being worked on, both sides of the switch should be grounded. 2.31.

If it becomes necessary to relocate a ground during the work procedure, it should not be removed until an additional ground is installed at the point of relocation.

2.32.

Safety grounds should not be dropped from structures. They should be stored in such a manner as to keep wear and tear to a minimum.

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2.33.

A systematic installation and removal procedure should be utilized using uniquely numbered ground disks and record-keeping to reduce the risk of leaving safety grounds in place when they should have been removed.

2.34.

Where multiple grounds are required for transmission line and substation equipment grounding due to increased fault current, only one ground rod shall be used for each ground cable. All ground rods shall be electrically connected (bonded).

2.35.

Multiple vehicle units (trucks, heavy equipment, etc.) may be connected to a single driven ground rod.

3.

Equipment Safety Grounds

3.1.

All equipment safety grounds shall be green jacketed or marked with a 3-foot-green heatshrink on the ground end.

3.2.

The attachment point (temporary or permanent) for equipment safety grounds must be capable of conducting the fault current for the time necessary to clear the fault. Equipment safety grounds shall be attached to equipment frames, bumpers, or heavy metal beds. Equipment safety grounds shall not be attached to sheet metal items, i.e., bins, tool boxes, or fenders.

3.3.

Equipment operators/drivers are responsible for ensuring that equipment safety grounds are installed and removed in accordance with these procedures.

3.4.

The person removing the equipment safety ground shall physically trace the ground from the equipment to the ground end before removing it.

3.5.

Equipment safety grounds shall be completely uncoiled while in use.

4.

Substation Grounding

4.1.

In addition to the following requirements, the requirements in paragraph 2, Installation and Maintenance of Safety Grounds – General apply.

4.2.

The station ground mats in substation and switchyards that conform to the requirements of "IEEE Guide for Safety in AC Substation Grounding (ANSI/IEEE STD. 80-1986) are considered an equipotential zone. All TVA substations and switchyards are designed to conform to ANSI/IEEE STD. 80-1986.

4.3.

Safety grounds in substations and switchyards shall be located as close as practical to the work area.

4.4.

When work is being performed on equipment such as transformers, regulators, or circuit breakers, a ground shall be placed on each bushing lead not visibly grounded. When it is necessary to test, grounds may be removed for the duration of the test and then replaced. The person holding the clearance or subclearance shall approve the removal and replacing of grounds. When the only work to be done is of a type that cannot be done with grounds in place, bringing a single ground into momentary contact with each bushing connection immediately before starting the work fulfills the intent of this requirement. If further work is to be done after tests are complete, the equipment shall be properly grounded.

4.5.

Neutral reactors shall not be worked on unless de-energized or bypassed with grounds.

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4.6.

After de-energizing capacitor banks, wait five (5) minutes before grounding them.

4.7.

Wye-connected capacitor banks may not have an installed ground on the wye-connection. If no installed ground is present, the wye shall be grounded before working on the bank.

4.8.

Ground switches shall not be used for safety grounding on primary circuits except as provided on gas-insulated switchgear and 3-phase ground switches in Kirk Key Systems for capacitor banks.

4.9.

Noncurrent-carrying metal parts of equipment or devices, such as transformer cases and circuit breaker housings, shall be treated as energized at the highest voltage to which they are exposed, unless an inspection of the ground strap prior to work being performed determines that these parts are grounded.

4.10.

Safety grounds shall be installed on newly constructed switchgear and/or buswork as soon as it is possible to energize it by any source (including induced voltages).

4.11.

Ground mat additions or separations shall be shunted to the existing mat with a safety ground prior to connection or disconnection.

4.12.

When applying safety grounds to transformers and other apparatus, be alert to possible capacity discharge. On rotating equipment, windings should be grounded long enough to drain off all charge before touching or attaching leads.

4.13.

On power circuit breakers with internal capacitors, safety grounds should be applied and the breaker closed to discharge the capacitors before work is performed.

4.14.

When work is being done on de-energized equipment on both sides of an air break switch, safety grounds should be installed on both sides of the switch or the switch should be closed, locked, and tagged to extend the ground circuit. In no case should a circuit breaker be used for this purpose.

4.15.

Mobile equipment should be grounded when used in a substation. Where the fence ground and the station ground are separated, this equipment should not be set up within 2.1 meters of the fence. If this is not possible, the fence ground and the station ground should be tied together for the duration of the setup.

4.16.

Only one safety ground shall be attached to each stirrup in locations where multiple grounds are required due to increased fault current.

5.

Gas-Insulated Switchgear Grounding

5.1

In addition to the following requirements, the requirements in paragraph 2, Installation and Maintenance of Safety Grounds – General apply.

5.2

Because of the construction of gas-insulated switchgear, the only access to the conductor is by means of a ground switch/test probe built into the grounded enclosure. Therefore, the ground switch must be used as a safety ground, but only if it meets the following criteria: •

It must be able to carry the available system short-circuit current.

•

It must be able to be disconnected from the motor operator.

•

It must be lockable in the closed position.

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5.3.

Before closing the ground switches, the person doing the switching shall determine that the disconnect switches are fully open. There is no provision for "buzzing" the conductor.

5.4.

The person holding clearance is responsible for verifying that the disconnect switch is fully open and that the ground probes are fully inserted into each phase bus.

5.5.

Employees shall not look in gas-insulated switchgear portholes during switching operations.

6.

Transmission Line Grounding

6.1.

In addition to the following requirements, the requirements in paragraph 2, Installation and Maintenance of Safety Grounds – General apply.

6.2.

Where an equipotential worksite safety grounding system is established, employees on the ground shall be protected from hazardous step and touch potentials by grounding mats, insulating platforms, or markers.

6.3.

Markers shall be installed to provide a 10-foot buffer zone around temporary safety ground rods used in the worksite safety grounding system.

6.4.

Equipment electrically bonded to the worksite safety grounding system shall be operated from insulated platforms or grounding mats bonded to the equipment being operated.

6.5.

Uninsulated Overhead Ground Wires (OHGW) shall be connected as part of the worksite safety grounding system.

6.6.

Insulated OHGW shall not be used in the worksite grounding system; the insulated OHGW shall be treated as an energized 13-kV conductor unless it is properly cleared and grounded.

6.7.

A conductor shall not be opened by cutting or jumper removal in a manner that will isolate a portion of the line from the safety ground.

6.8.

A ground cluster block should be used as an intermediate connection between the safety ground leads, pole ground wires, if any, and the temporary ground rod. The #4 iron down wire pole grounds must not be used as the safety ground even when multiple ground wires are available. A safety ground(s) sized appropriately for the available fault current must be provided independent of the #4 iron wire pole ground. The #4 iron wire should be bonded to the safety ground via the cluster block.

6.9.

A steel crossarm may be used in lieu of a ground cluster block after arm connections to the pole grounds have been inspected.

6.10.

A pole ground wire used for safety grounding should be inspected before grounding to determine that it has not been cut or damaged.

6.11.

If necessary to provide proper climbing clearance, an underbuilt circuit on the same structure with the transmission circuit to be grounded should be de-energized and properly grounded before placing the transmission safety grounds. When this is not practicable, the energized underbuilt circuit should be set out in hotsticks or covered with appropriate protective covering to obtain this clearance.

6.12.

The ground switches at 500-kV terminals should be closed before safety grounds are installed on the line.

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6.13.

Any type OHGW, except those insulated for communications, should be considered as a secondary ground source and used as a primary ground source only when it is the least hazardous alternative.

6.14.

Safety ground rods should be 1.59 centimeter, bronze, copper, or copperweld at least 1.5 meters long and be of the driven type.

6.15. Ground rods should be driven to the maximum depth possible. If a rod cannot be driven 1.2 meters, a total of three (3) rods shall be driven in a triangular pattern 1.5 to 3 meters between each one and as deep as possible. The three (3) rods should be electrically connected with safety grounds prior to connecting them to the worksite safety grounding system. 6.16.

Temporary ground rods should be protected from tampering by the public.

6.17.

Guy wires should not be used as a ground path.

7.

Conductor Stringing or Removal-Grounding

7.1.

In addition to the following requirements, the requirements in paragraph 2, Installation and Maintenance of Safety Grounds – General apply.

7.2.

Only approved protective devices shall be used in stringing operations.

7.3.

Traveling grounds shall exert constant pressure on the wire being pulled.

7.4.

Pulling and tensioning equipment shall be bonded and effectively grounded and not operated from the ground except from bonded mats.

7.5.

Approved traveling grounds shall be installed within 6.1 meters of the tensioning and pulling machines in order to ground each pulling line, conductor, subconductor, and OHGW.

7.6.

Pulling lines, conductors, subconductors, and OHGW shall be grounded at the first structure from the tensioner, puller, wire reel, or snub point.

7.7.

Conductors, subconductors, and OHGW shall be grounded adjacent to all dead ends or catch-off points.

7.8.

An approved ground shall be located on each side of and as close as possible to the work area where splices are being made at ground level. The two ends of a conductor being spliced shall be bonded together.

7.9.

Where conductors are installed parallel to existing energized conductors and employees are working on bare conductors, grounds shall be placed at each location where these employees are working.

8.

Grounding of Overhead Ground Wires

8.1.

Overhead ground wires (OHGWs), also called shield wires or static wires, may be insulated (IGWs) or uninsulated. Insulated ground wires may be used as communication circuits. Both OHGWs and IGWs are capable of providing lethal levels of energy at a worksite from remote grounds (ground rise), electrostatic coupling, electromagnetic coupling or inadvertent contact with energized conductors. IGW with communications paths will also have potentially lethal currents due to these signal paths.

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8.2.

Both energized and de-energized work may be performed on the line conductors/circuits that have each type of OHGW. When the work requires grounding IGWs the Network Management Center (NMC) must be notified. A Hold Order will then be required for the IGW and the circuit will then be grounded at the worksite. No further communications switching for grounding or issuance of the Hold Order will be required. In this case, communications circuit grounding switches, if they exist, may remain open.

8.3.

When the power circuit is worked, either energized or de-energized, any OHGW must be grounded with safety grounds at the site and treated as a source of lethal energy when not grounded.

8.4.

When the power circuit is worked, either energized or de-energized, the IGW must be treated as an energized 13 kV circuit unless it can be grounded at the work site.

8.5.

Work site grounding of OHGWs and IGWs constitute the clearance for work on these ground conductors when they are grounded. The dispatcher does not issue clearance on them as they are not power circuits. Before grounding an IGW, request the dispatcher to receive permission to do so via the NMC.

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Minimum Clearance Distances for Energized Work 1.

Purpose

1.1

The purpose of this procedure is to establish minimum clearance distances for energized work.

2.

Minimum Clearance Distances for Energized Work

2.1

The following minimum clearance distances shall be maintained for all types of energized work except as permitted by use of approved barriers, guards, insulated tools, or insulated aerial lift equipment. Nominal Voltage (Phase -to-Phase) kV 13 26 46 69 115 161 230 345 500 750

Minimum Clearance Distances (Phase -to-Ground) Centimeters 63.50 71.12 78.74 91.44 101.60 121.92 160.02 259.08 302.26* 457.20

Minimum Clearance Distances (Phase -to-Phase) Centimeters 66.04 78.74 86.36 106.68 137.16 172.72 254.00 406.40 609.60 944.88

*Note: Switching over voltage factor is 2.2 which allows a phase-to-ground minimum clearance distance of 302.26 centimeters. The procedure listed below should be substituted for the 302.26 centimeter minimum working clearance distance on electrical circuits rated at 500 kV if the circumstances exist as described below: 1. On transformer-terminated lines and reactor-terminated lines, a 104.14-centimeter air gap device should be installed and at least 213.36 centimeters of clearance maintained. 2. In circumstances where 302.26 centimeters of clearance cannot be maintained, a 104.14-centimeter air gap device should be installed and at least 213.36 centimeters of clearance maintained.

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Section 12 Transmission / Generation / Electrical Testing / Telecommunication Work Activities Number

Subject

Revision

1201

General Requirements for Transmission, Substation and Telecommunication

3

1202

Electrical Testing

1

1203

Energized Equipment Maintenance

1

1204

Helicopter Operations for Transmission Line Work

1

1205

Insulator Cleaning on Energized Circuits and Equipment

1

1206

Live-line Work

1

1207

Stringing and Removing Conductors

2

1208

Transmission Line Work

3

1209

Right-of-Way Clearing and Grounds Maintenance

2

1210

Telecommunication Safety Requirements

2

1211

Telecommunication Tower Climbing

0

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General Requirements for Transmission, Substation and Telecommunication 1.

Purpose

1.1.

The purpose of this procedure is to provide a summary of the general requirements for transmission, generation, electrical testing, and telecommunication work activities.

1.2.

In addition to the requirements specified in this procedure, the requirements defined in the referenced TVA Safety Procedures shall apply. This procedure includes the following: •

Heavy Equipment Reference: TVA Safety Procedure 711, “Heavy Equipment Operations”

•

Electrical Storage Batteries Reference: TVA Safety Procedure 1019, “Wet Cell Storage Batteries”

•

Scaffolds Reference: TVA Safety Procedure 813, “Scaffolds and Temporary Work Platforms”

•

Excavations and Trenching Reference: TVA Safety Procedure 804, “Excavations and Trenching”

•

Ropes, chains, and rigging hardware Reference: TVA Safety Manual, Useful Information 1607, “Rigging / Lifting” Power Generating Plant Work

•

Nuclear Plants

•

All Terrain Vehicles Reference: TVA Safety Procedure 601, “All Terrain Vehicles”

2.

Aerial Lifts

2.1

Requirements for operating or working in aerial lifts are included in TVA Safety Procedure 702, “Aerial Lifts”.

3.

Heavy Equipment

3.1.

Mechanical equipment, when not in use or left unattended, shall have keys removed from ignition switches or the equipment reasonably disabled to prevent starting by unauthorized personnel.

3.2.

When heavy equipment is being transported on a trailer, as a minimum, a 4-point tiedown method shall be used.

3.3.

The aggregate static Working Load Limit (WLL) of tie-down assemblies used to secure an article against movement during transport shall be equal to at least ½ (0.5) times the weight of the article. An even number of chains shall be used. The WLL shall be determined either from the charts in Procedure 1607 or the tags or labels attached to the tie-down assembly.

3.4.

Example: divide weight of load to be hauled by 2 and divide that number by the strength of the chain from chart or tag. This will give the number of chains required: Load = 33,566 kilograms: 33,566 kilograms ÷ 2 = 16,783 kilograms.

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3.5.

Strength of chain from chart: 3,221 kilograms and 16,783 ÷ 3,221 = 5.21, therefore, 6 chains required.

3.6.

Seat belts shall be installed, maintained, and worn on equipment with rollover protection.

3.7.

When left unattended, bulldozer blades, earth moving buckets, and bushhogs shall be placed on the ground.

3.8.

Risks shall be thoroughly evaluated before loading or unloading heavy equipment.

3.9.

Only qualified operators should operate heavy equipment, i.e., bulldozers, loaders, backhoes, hole diggers, track drills, anchor installers, stringing equipment, etc.

3.10.

Bulldozers should be parked on timber whenever there is the possibility of freezing temperatures.

3.11. Bulldozer tracks, rollers, and idlers should be cleaned daily. 4.

Electrical Storage Batteries

4.1

The following protective equipment shall be used by employees when performing battery maintenance (not required for routine tests). •

Either goggles or plastic face shield or both.

•

Protective gloves.

•

Protective apron or rain suit.

4.2.

Before work on batteries is initiated, employees shall ensure that a fully operational eyewash is close at hand in case of an electrolyte splash to the eyes. If electrolyte spills on skin, rinse with clear water promptly.

4.3.

The battery compartment or room shall be well ventilated before placing a battery on equalizing charge.

4.4.

Do not smoke or use open flames around batteries. Post "NO SMOKING" signs in battery rooms where they are clearly visible to anyone entering.

4.5.

Only spirit thermometers shall be used when taking electrolyte cell temperature. Mercury thermometers could break, and mercury running into the cell between the plates will cause sparking and possible explosions.

4.6.

Cell vent plugs shall be kept firmly in place at all times except when adding water or taking hydrometer readings. (These vent plugs shall be the flame-arrester type.)

4.7.

Tools used for tightening connector bolts shall have insulated handles. Rings, wristwatches, etc., shall be removed before working on the battery.

5.

Scaffolds

5.1.

Unnecessary tools, materials, and debris shall not be allowed to accumulate in quantities to cause a hazard.

5.2.

Guardrails (top-rail, mid-rail and toe-board) shall be made an integral part of all scaffolds.

5.3.

Scaffolds shall not be overloaded.

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5.4.

Before using any stationary scaffold, employees should make a careful inspection to satisfy themselves that all parts are in a safe condition and securely fastened together, set on an adequate foundation, and plumbed.

5.5.

Do not jump on or off scaffolds.

5.6.

Barricade around scaffolds whenever practicable. If the area must be used as a walkway, adequate overhead protection shall be provided.

6.

Excavations and Trenching

6.1

The location of utility installations, such as sewer, telephone, fuel, electric, or any other that may be encountered during excavation work, shall be determined prior to opening the excavation.

6.2.

All excavations left unattended shall be covered or barricaded with suitable material to provide protection for people and vehicular traffic. See safety color code for marking physical hazards in TVA Safety Manual, Useful Safety Information 1608 “Color Codes for Marking Physical Hazards and the Identification of Certain Equipment”.

6.3.

No employee shall work in an open excavation with a load suspended overhead.

6.4.

No employee shall work in any excavation more than 1.2 meters in depth until it has been inspected by a competent person and any required protective system installed to protect employees from cave-in.

6.5.

Employees shall not be lowered into or raised out of an excavation by mechanized equipment other than equipment suitable for this purpose.

6.6.

Excavated or other materials or equipment shall be at least 0.6 meters from the edge of excavations, or retaining devices shall be used to prevent materials and equipment from falling or rolling into excavations. A combination of these methods shall be used if necessary to provide employee protection.

6.7.

Employees shall not work in excavations deeper than 1.2 meters without a stairway, ladder, ramp, or other safe means of entrance and exit.

6.8.

When mobile equipment is operated adjacent to an excavation, or when such equipment is required to approach the edge of an excavation, and the operator does not have a clear and direct view of the edge of the excavation, a warning system shall be used such as a barricade, hand or mechanical signals, or stop logs.

6.9.

Vehicles shall not be parked where they could roll either forward or backward into an excavation.

6.10.

Employees shall be adequately protected from loose rock or soil that could pose a hazard by falling or rolling from an excavation face. Such protection shall consist of scaling to remove loose material; installation of protective barricades at intervals, as necessary on the face to stop and contain falling material; or other protective means.

6.11.

Employees shall not work on the faces of sloped or benched excavations at levels above other employees except when employees at the lower levels are adequately protected from the hazard of falling, rolling, or sliding material or equipment.

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Where oxygen deficiency or a hazardous atmosphere exists or could reasonably expect to exist, such as in excavations in landfill areas, near sewers, or natural gas lines, the atmospheres in the excavations shall be tested before employees enter excavations greater than 1.2 meters in depth.

6.13. Adequate precautions shall be taken to prevent employee exposure to atmospheres containing less than 19.5 percent oxygen and other hazardous atmospheres. 6.14. Adequate precaution shall be taken to prevent employee exposure to an atmosphere containing a concentration of a flammable gas in excess of 10 percent of the lower flammable limit of the gas. 6.15. When controls are used that are intended to reduce the level of atmospheric contaminants to acceptable levels, testing shall be conducted as often as necessary to ensure that the atmosphere remains safe. 6.16.

Emergency rescue equipment shall be readily available where hazardous atmospheric conditions exist or may reasonably be expected to develop during work in an excavation. This equipment shall be attended.

6.17.

Employees entering bell-bottom pier holes, or other similar deep and confined footing excavations, shall wear a body harness with a lifeline attached to it. The lifeline shall be individually attended at all times while the employee is in the excavation.

6.18.

Employees shall not work in excavations in which there is accumulated water, or in excavations in which water is accumulating, unless adequate precautions have been taken to protect employees against the hazards posed by water accumulation.

6.19. A competent person for excavation means one who is capable of identifying existing and predictable hazards in the surroundings, or working conditions which are unsanitary, hazardous, or dangerous to employees, and who has authorization to take prompt corrective measures to eliminate them. 6.20.

If water accumulation is controlled by the use of water removal equipment, the equipment and operations shall be monitored by a competent person to ensure proper operation.

6.21.

If excavation work interrupts the natural drainage of surface water (such as streams), diversion ditches, dikes, or other means shall be used to prevent surface water from entering the excavation and to provide adequate drainage of the area adjacent to the excavation. Excavations subject to runoff from heavy rains require an inspection by a competent person.

6.22.

Daily inspections of excavations, the adjacent areas, and cave-in protective systems shall be made by a competent person for evidence of a situation that could result in possible cave-ins, indications of failure of protective systems, hazardous atmospheres, or other hazardous conditions. An inspection shall be conducted by the competent person prior to the start of work and as needed throughout the shift. Inspections shall also be made after every rainstorm or other hazard increasing occurrence. These inspections are only required when employee exposure can be reasonably anticipated.

6.23.

Where the competent person finds evidence of a situation that could result in a possible cave-in, indications of failure of protective systems, hazardous atmospheres, or other

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hazardous conditions, exposed employees shall be removed from the hazardous area until necessary precautions have been taken to ensure their safety. 6.24. Where employees or equipment are required or permitted to cross over the excavation, walkways or bridges with standard guardrails shall be provided. 7.

Ropes, Chains, and Rigging Hardware

7.1.

Synthetic rope slings shall not be used to catch off or suspend conductors or ground wires. Voltage bleed-off may cause synthetic slings to fail.

7.2.

Chokers, wire rope, chain, or other rigging hardware shall be of adequate size, type, condition, and arrangement to safely handle the load. (See TVA Safety Manual, Useful Safety Information 1607, “Rigging / Lifting”.)

7.3.

An employee shall warn other employees of unsafe rigging observed.

7.4.

Rigging equipment shall be inspected before each use, and any found defective shall be tagged defective and not used until repaired, or it shall be discarded.

7.5.

When chain is used for lifting, only alloy steel chain shall be used.

7.6.

Chain used for rigging shall not be shortened by twisting, knotting, or with nuts and bolts.

7.7.

Before using chain to lift a load, each link shall be inspected for wear, nicks, gouges, stretch, corrosion, shear, and localized bending.

7.8.

Wire rope slings or running rope shall be replaced if there are six or more randomly distributed broken wires in one rope lay or three or more broken wires in one strand in one rope lay. (A rope lay is that length along the rope in which one strand makes one complete revolution around the rope.)

7.9

Wire rope slings or running rope shall be replaced if the individual wires in the outer layer are worn by one-third the original diameter of the wire.

7.10.

Shackles used for rigging shall be discarded if worn in the crown or in the pin by more than 10 percent.

7.11.

Cold shuts, lap links, quick links, or "missing" links shall not be used for chain repair or to attach hooks.

8.

Power Generating Plant Work

8.1.

There are risks in the operation and maintenance of generating plants that are not found in other electrical installations. The requirements in this paragraph deal with the risks peculiar to these plants and shall be strictly observed by employees. Employees are also responsible for observance of all other requirements that are applicable. Plant safety rules shall be followed where applicable.

8.2.

Cubicles containing electrical equipment shall be entered only by experienced persons in the performance of their duties.

8.3.

When normal barriers, such as guardrails, floor gratings, hatch covers, deck plates, or equipment, are removed leaving unattended openings in decks, floors, and gratings, temporary barriers shall be installed and maintained while work is in progress.

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8.4.

Employees shall not enter or leave a machine unless the person in charge of the work is informed.

8.5.

All persons shall be out of the machine and accounted for by the person responsible for the work before it is released to service.

8.6.

In no case shall an employee stand on or between wicket-gate arms and rings while equipment is in operation.

8.7.

All tools, personal effects, and foreign material shall be removed from the generating unit before it is readied for service.

8.8.

If work is to be performed in the generator enclosure, the CO2 automatic fire protection system shall be cleared and tagged under the authorized plant operating procedure.

8.9.

Employees shall not enter the generator casing until all gas has been replaced by air and the casing is known to contain a life-sustaining atmosphere. Smoking or open flames shall not be permitted.

8.10.

Employees shall not enter a wheel pit after a generator CO2 discharge until the measures in Confined Space Entry have been taken. See TVA Safety Procedure 801, “Confined Space Entry”.

8.11. Appropriate protective equipment shall be worn by employees performing work in areas that present special hazards, such as flying particles, falling objects, hot metal, exposure to chemicals, and irritating or toxic gases. 8.12.

Employees, upon entering and leaving supervisory-controlled stations, should report to the operator/dispatcher in charge of the station.

8.13.

Rope, air lines, or extension cords coiled or intermingled on walkways, stairways, or landings are prohibited. Protect electrical cords or air lines by use of temporary boards at roadway or walkway crossings.

8.14.

When in wheel pits, employees should stand in a safe position for maintaining balance and should keep hands and fingers in the clear.

8.15.

Employees should not step or stand on parts of an idled generator or turbine subject to rotation. They should maintain the proper clearance from all mechanical and electrical parts until the machine is cleared and tagged under the established procedure from all sources of energy, both hydraulic and electrical, including headgates being set and tagged.

8.16.

Employees should be extremely cautious while working on or near collector rings or commutators while the generator is in operation. They should also remove all loose material from pockets in clothing before beginning such work.

8.17.

When work is performed near the generator rotor brake cylinders, keep fingers and hands clear of the pressure surfaces of the brake cylinders.

8.18.

When cleaning or working in actuator cabinets with the equipment in service, stay clear of parts subject to movement.

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9.

Nuclear Plants

9.1.

The nonradiation hazards associated with the operation of a nuclear plant are similar to those in other plants. Therefore, many safety requirements from other portions of paragraph 9, Power Generating Plant Work, are applicable. Separate requirements for hazards peculiar to nuclear plants will be added as necessary.

9.2.

Permissible dose rates, exposure limits, and rules for control are contained in the TVA Health Physics Manual. The limits and controls specified therein shall be adhered to as though written here.

9.3.

Because of the nature of the hazards associated with a nuclear facility, specific written procedures are required for emergencies at each plant. These procedures, including site evacuation and plans with local civil authorities, will be issued before the startup of a nuclear unit at any facility.

10.

All Terrain Vehicles

10.1.

ATVs equipped with a single front tire shall not be used on transmission line rights-ofway.

10.2.

ATVs shall be equipped with roll over protection, bench seat, and seat belts for each passenger.

10.3.

Personal Protective Equipment (PPE) shall include a hard hat and safety eyewear.

10.4. ATVs are for off-road operations and should not be driven on public streets and roads. 10.5. When tools or equipment are transported, they should be properly secured on the vehicle. 10.6.

A personal flotation device should be worn when fording streams that could cause the tires to float.

10.7. ATVs are intended to be operated at safe speeds, depending on terrain and conditions. At no time should an ATV be operated in an unsafe manner or used for purposes other than its intended use. 10.8. Passengers shall only be permitted when the vehicle is equipped with the manufacturersapproved seating for passengers except in the event of a medical emergency.

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Part III: Worker Safety Rules

Electrical Testing 1.

Purpose

1.1

The purpose of this procedure is to establish safety requirements for electrical testing at reduced, normal, or high potentials. It applies only to testing involving interim measurements and not to testing involving continuous measurements as in routine metering, relaying, and normal maintenance and operations work.

2.

General

2.1.

Electrical test work is different in many important respects from other power system activities. Consequently, special attention must be given to work hazards and safety in performance of electrical tests. In many cases, tests and adjustments make it necessary to energize equipment at reduced, normal, or high potential. Therefore, the possibility of electrical shock to test employees and others in the vicinity must be a constant consideration.

2.2.

Always assume any equipment is energized until checks have been made to verify that the circuit is cleared. Make sure that the person holding the clearance is aware that test work is in progress and that the clearance will be held until the test work is complete.

2.3.

When grounds are removed temporarily during tests, each employee shall use insulating equipment and be isolated from any hazards involved, and additional measures shall be instituted as necessary to protect each exposed employee in case the previously grounded lines and equipment become energized.

2.4.

Unless proper precautions are taken, alternating current test potential applied to a secondary circuit or device (such as a relay or meter) can feed back through transformers, develop primary voltage at the high-voltage terminals, and energize any connected buses or equipment. Before energizing secondary circuits or devices, isolate them from the transformers or make sure the high-voltage terminals are in the clear and are guarded properly.

2.5.

On large pieces of equipment or on equipment mounted at heights, safe practices should be followed in the handling of ladders or other means of access. Physical injury from slips, falls, and improper lifting should be constantly guarded against.

2.6.

During fault conditions, dangerous voltages may exist between a station ground and a remote ground (including a fence ground). Therefore, leads and equipment connected to one ground should be treated as hot with respect to other grounds. In the course of ground impedance measurements, or other tests when it is necessary to contact leads or equipment connected to a distant ground, rubber gloves or other protective equipment should be used.

2.7.

Specific safety precautions to be taken during the various types of test work are given in each section of the Field Test Manual for transmission line, substation, and switchyard activities. These precautions should be followed carefully in the performance of electrical test work.

3.

Rotating Equipment Testing

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3.1

Windings to be tested shall be grounded long enough to drain off any charge before being touched. This is particularly important after dc high-potential and dielectric absorption tests (grounding time may exceed one hour).

3.2.

Windings to be grounded shall be solidly grounded to the station ground. Test equipment shall be connected to the same grounding point.

3.3.

Apparatus undergoing test shall be identified by means of orange tape. See TVA Safety Procedure 1107, “Identifying Energized Electrical Hazards”.

3.4.

No one except those directly involved with the test shall be allowed in the taped-off area while a test is in progress.

3.5.

When applying a test voltage to voltage-regulating equipment, be sure the test voltage does not unintentionally energize any voltage transformers.

4.

High-Potential Testing

4.1.

Apparatus undergoing test shall be identified by means of orange tape or by an interlocked fence. The tape shall be taken down if there is a long delay between tests.

4.2.

There shall be a definite understanding between the test set operator and others helping make the tests about the number of tests to be made, duration, and voltage values to be impressed on the various parts of the apparatus. All others working in the vicinity shall be warned not to enter the isolated area and not to carry pipes or other long material which may protrude into the area.

4.3.

The test set voltage controls shall be run down to the lowest position after each test and left there before the all-clear signals are given. The energizing plug shall be pulled; or, where a knife switch is used, it must be open before the all-clear signal is given. An open power circuit breaker is not sufficient clearance.

4.4.

The apparatus under test shall be solidly grounded to the station ground, and the test set ground lead shall be attached to the same grounding point.

4.5.

No one except those directly involved with the tests shall be allowed inside the taped-off or fenced-off areas while tests are in progress.

4.6.

Test leads carrying high potential may need to be supported with insulating tape. This tape shall not be tied off to ungrounded supports.

4.7.

During dc high-potential tests, ground all conductive bodies within the field of influence of the test set and the specimen under test to prevent a buildup of dc voltage on such bodies due to capacitance voltage divider action.

4.8.

After dc high potential tests, ground the test specimen long enough to drain off its charge. High-capacitance specimens, such as generators or cables, may require grounding times of an hour or more. A dc high potential may reappear on the test specimen if the ground is removed too soon.

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Energized Equipment Maintenance 1.

Purpose

1.1

The purpose of this procedure is to establish requirements for energized equipment maintenance.

2.

Requirements for Energized Equipment Maintenance

2.1.

Where there is a possibility of remote or automatic reclosing, a caution order shall be obtained before working on or near any equipment where a system voltage may be contacted.

2.2.

Only tools and equipment designed, tested, and approved for live-line work shall be used. All work shall be personally supervised by a person qualified to perform this work.

2.3.

Work shall not be permitted while there is any indication of lightning in the vicinity.

2.4.

Live-line equipment shall be wiped clean and visually inspected prior to use each day in accordance with TVA and/or the manufacturer’s instructions. Any discrepancies shall be reported to the supervisor and corrected before equipment use (see TVA Safety Procedure 1206, “Live Line Work”).

2.5.

When approaching, leaving, or bonding to an energized part, workers shall maintain themselves and their conductive equipment at a distance from other energized or grounded parts at least equal to the minimum approved phase-to-phase and phase-toground clearance distances (see TVA Safety Procedure 1110, Minimum Clearance Distances for Energized Work”).

2.6.

A 104.14-centimeter air gap device shall be installed immediately adjacent to the work location before working on transformer-terminated or reactor-terminated 500-kV lines or when the 302.26-centimeter clearance distance to a grounded surface cannot be maintained, then the minimum clearance shall be 231.36 centimeters.

2.7.

Approved conductive clothing designed for live-line, bare-hand work shall be used for all bare-hand work above 230 nominal kilovolts.

2.8.

Employees using the live-line, bare-hand technique shall wear conductive footwear or other bonding equipment designed for the same purpose.

2.9.

Before any employee uses the live-line, bare-hand technique on energized high-voltage conductors or parts, the following information shall be determined. •

The nominal voltage rating of the circuit on which the work is to be performed.

•

The minimum clearance distances to ground from lines and other energized parts on which work is to be performed.

•

The voltage limitations of equipment to be used.

2.10.

Insulated equipment, insulated tools, and aerial devices and platforms used shall be designed, tested, and intended for live-line, bare-hand work. Tools and equipment shall be kept clean and dry.

2.11.

Work shall not be performed when adverse weather conditions would make the work hazardous. Additionally, work shall not be performed when winds reduce the phase-toIII-251

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phase or phase-to-ground minimum clearance distances at the work location below that specified in TVA Safety Procedure 1110,” Minimum Clearance Distances for Energized Work”, unless the grounded objects and other lines and equipment are covered by insulating guards. 2.12.

For live-line, bare-hand work, a nonconductive measuring device shall be readily accessible to assist employees in maintaining the required minimum clearance distance.

2.13.

A telescoping fiberglass measuring stick designed for that purpose should be used for measuring minimum clearance distances.

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Helicopter Operations for Transmission Work 1.

Purpose

1.

The purpose of this procedure is to establish requirements for helicopter operations for transmission work.

2.

Requirements

2.1.

The use of helicopters to support our work activities results in unique hazards that require special precautions.

2.2.

The helicopter pilot shall conduct a pre-job safety briefing with all involved employees before the job begins. This briefing shall include, but not be limited to, the following: •

Safety related specifications of the helicopter and other equipment to be used

•

Safety zone when the aircraft is on the ground with the rotors turning

•

The distance from the helicopter to the quick connect/disconnect

•

The hand signals used

•

The verbal commands used for normal operations, to indicate a problem, and to stop operations.

2.3.

The pilot shall review emergency and general procedures with employees who fly in the helicopter.

2.4.

Passengers in an aircraft shall follow the instructions of the pilot-in-command.

2.5.

The foreman or the pilot-in-command shall halt operation in the event a change in plans is required. Operation shall not resume until a new plan is agreed upon and discussed with all involved.

2.6.

When hooking up a load, a member of the ground crew shall be in radio contact with the pilot and/or with the flight crew member (spotter) who is guiding the pilot.

2.7.

Ground-to-air radio communications shall be checked for proper operation prior to starting helicopter operations involving the ground personnel. In the event that a ground crew member believes an unsafe condition is developing regarding the aircraft, they shall contact the pilot using the agreed upon verbal communications.

2.8.

During the work, ground personnel shall minimize radio communications to avoid confusing the pilot and spotter.

2.9.

Communication systems between the pilot and/or spotter and ground personnel shall be understood and checked in advance of hoisting the load. This applies to either radios or helicopter hand signals (see Useful Safety Information, 1603 “Hand Signals for Helicopter Operations”).

2.10.

When employees are required to perform work under hovering craft, a safe means of access shall be provided to reach the hoist line hook and engage or disengage cargo slings. Employees shall not perform work under hovering craft except when necessary to hook, unhook, secure or place loads.

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2.11.

Every practical precaution shall be taken to provide for the protection of employees from flying objects in the rotor down-wash. All loose materials within 30.5 meters of the place of lifting the load, depositing the load, and all other areas susceptible to rotor down-wash shall be secured or removed.

2.12.

Employees working in the vicinity of helicopter operations shall wear hearing protectors, goggles, and hard hats with chin straps. Loose-fitting clothing likely to flap in the downwash, and thus be snagged on the hoist line, shall not be worn.

2.13.

The helicopter load hook shall be a quick connect/disconnect type. A hands-on demonstration of the quick connect/disconnect shall be performed by all crew members who will operate it. Tag lines shall be of a length that will not permit their being drawn up into rotors.

2.14.

Pressed sleeve, swagged eyes, or equivalent means shall be used on wire rope slings for all freely suspended loads because hand splices may spin open or cable clamps loosen.

2.15.

Wire rope shall be used to connect a suspended load to the hoist line hook.

2.16.

No unauthorized person shall be allowed to approach within 15.2 meters of the helicopter when the rotor blades are turning.

2.17.

Whenever approaching or leaving a helicopter with blades rotating, all employees shall remain in full view of the pilot and keep in a crouched position. Employees shall avoid the area from the cockpit or cabin rearward (toward the tail rotor) unless authorized by the pilot to work there.

2.18.

There shall be no smoking within 15.2 meters of the helicopter.

2.19.

Open fires shall not be permitted in an area that could result in such fires being spread by the rotor down-wash.

2.20.

Employees may assist in field refueling operations only under the direction of the flight crew. Smoking or open flames are prohibited within 15.2 meters of the refueling area.

2.21.

Poles, crossarms, etc., should be transported vertically to reduce in flight motion.

2.22. Dust masks should be worn when dusty conditions exist.

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Insulator Cleaning on Energized Circuits and Equipment 1.

Purpose

1.1

The purpose of this procedure is to establish safety requirements for insulator cleaning on energized circuits and equipment.

2.

Basic Requirements

2.1.

Cleaning insulators can be safely accomplished by either of two methods, washing with high-pressure distilled water or by use of compressed air and an abrasive material.

2.2.

The compressed-air method can be used for all types of contaminants and is the only method to remove some deposits. •

Some individuals experience discomfort from static discharge to their body from the laminated tubing using this method.

•

This can be eliminated by bonding the body to the nozzle with a conductive strap.

•

High-pressure distilled water can be more efficient for removing less adherent deposits if the physical arrangement of the equipment allows its use.

3.

Compressed Air Method

3.1.

All equipment, such as air compressors, specially adapted sandblaster, hose, and laminated tubing shall be approved for this work.

3.2.

Only approved cleaning materials, such as lime, pulverized corncobs, and walnut hulls, shall be used.

3.3.

The laminated tubing used as a nozzle shall be electrically tested as follows: •

Test at 75 kV per foot before use.

•

Test at 75 kV per foot with air and grit flowing before use.

•

Observe for static buildup and discharge.

•

Check leakage current as cleaning operation is commenced, beginning at insulator base and advancing to energized circuit. Leakage current shall not exceed two milliamperes.

3.4.

The requirements in TVA Safety Procedure 1203, “Energized Equipment Maintenance”, relating to work on energized circuits and equipment shall be observed.

3.5.

The air stream shall never be directed toward people.

3.6.

The following approved protective equipment shall be used: •

Respirator

•

Eye protection

•

Hearing protection

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3.7.

Weather conditions have a direct effect on the operation of the cleaning equipment. Normally, work should be suspended during periods of high humidity or when the ambient temperature is below 40 degrees F.

3.8.

The water trap on the air compressor should be checked frequently and emptied as necessary.

3.9.

When using a telescopic boom, care should be taken to prevent grit from contacting the boom surface.

4.

Pressurized Water Method

4.1.

Since the resistivity of water varies widely from distilled water to contaminated water, leakage currents associated with live-line washing vary proportionately to the quality of the water.

4.2.

Each tank of water shall be tested immediately before use. Water resistivity of less than 2500 ohms per cubic centimeter shall not be used.

4.3.

Only special high-pressure nozzles and hose designed for this service shall be used. The nozzle shall not be directed toward people.

4.4.

The nozzle, hose, tank, truck, platform, and all washing equipment shall be grounded.

4.5.

When washing insulators or bushings on energized equipment of buses, maintain clearances between the grounded nozzle and the energized equipment as outlined in the following table:

4.6.

Before attempting live-line washing, the foreman should review and see that the crew is thoroughly familiar with special instructions covering this subject.

4.7.

Avoid shooting a direct stream of water on disconnect switches. There may be enough pressure in the stream to move the blades if applied in the right direction. For the same reason, be careful with the stream around jumper loops and potential transformer leads, both primary and secondary. Caution should be observed to avoid a direct stream on breathers, gasketed joints on transformers, breakers, and bushings.

4.8.

Since complete washing is essential, be sure there is sufficient water in the tank to finish washing an insulator once washing has been started.

4.9.

Extreme caution should be exercised in handling the water gun at high pressure. Keep the gun pointed down at all times except when in actual use. Never point the gun otherwise until ready to use. The person operating the wash truck should be sure that those using the guns are ready before opening the valves or starting the pump. Nominal Voltage 13 kv 26 kv 46 kv 69 kv 115 kv 161 kv

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6.4 Millimeter Nozzle or Smaller 2.7m 3.0m 3.4m 3.7m 4.0m 4.6m

4.8 Millimeter Nozzle or Smaller 1.8m 2.1m 2.4m 2.7m 3.0m 3.4m

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Part III: Worker Safety Rules

Live-Line Work 1.

Purpose

1.1

The purpose of this procedure is to establish safety requirements for live-line work.

2.

Requirements

2.1.

The final decision of whether live-line work can be done safely is the responsibility of the supervisor directing the work. The supervisor shall ensure that the crew is properly trained for the work on energized equipment; that proper tools and equipment are used and that correct safety measures are implemented.

2.2.

Electrical circuits and equipment shall be considered energized until they are properly grounded.

2.3.

A caution order shall be obtained on any transmission line or substation equipment being worked on while energized.

2.4.

Employees performing energized work on the same structure shall not work on different phases at the same time.

2.5.

Rubber gloves shall not be used with hotsticks for live-line work.

2.6.

While working or climbing nearer than 7.6 meters to energized conductors or parts on 500-kV transmission line structures, workers shall wear conductive-sole shoes or other bonding equipment designed for that purpose.

2.7.

Conductive material shall not be hung on the lip of the aerial lift bucket in such a way as to reduce required clearances.

2.8.

Only ropes that are maintained specifically for live-line work shall be used on energized lines or equipment.

2.9.

All live-line tools when not in use shall be kept clean and dry in approved protective containers.

2.10. Live-line tools shall be visually inspected and wiped clean before use in accordance with TVA Safety Procedure 1103, “Electrical Protective Equipment”. 2.11. While equipment, lines, or buses are energized, no employee at ground potential shall touch insulators, bushings, lightning arresters, or insulator pins except as provided by special work procedures. 2.12. When tying or untying energized conductors to or from insulators, keep the tie wire short enough to maintain clearance distance between the tie wire and the supporting structure. 2.13.

Insulated portions of hotline tools shall be properly tested for insulation value as required.

2.14.

When approaching or working on energized circuits, except from an insulated lift or similar device, the minimum distances as stated in Appendix A, Minimum Clearance Distances for Energized Work shall be followed.

2.15.

Before any energized equipment is worked on, consideration should be given to the arc that will result if accidental short circuiting or grounding occurs and plans should be made for that possibility.

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Appendix

3.1

Appendix A Minimum Clearance Distances for Live Line Work

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Appendix A Minimum Clearance Distances for Energized Work Nominal Voltage (Phase-toPhase) kV

13 26 46 69 115 161 230 345 500* 750

Minimum Clearance Distances (Phase-to-Ground) Centimeters

Minimum Clearance Distances (Phase-to-Phase) Centimeters

63.50 71.12 78.74 91.44 101.60 121.92 160.02 259.08 302.26* 457.20

66.04 78.74 86.36 106.68 137.16 172.72 254.00 406.40 609.60 944.88

*Note: Switching overvoltage factor is 2.2 which allows a phase-to-ground minimum clearance distance of 302.26 centimeters. The procedure listed below should be substituted for the 302.26-centimeter minimum working clearance distance on electrical circuits rated at 500 kV if the circumstances exist as described below: •

On transformer-terminated lines and reactor-terminated lines, a 104.14-centimeter air gap device should be installed and at least 213.36 centimeters of clearance maintained.

•

In circumstances where 302.26 centimeters of clearance cannot be maintained, a 104.14-centimeter air gap device should be installed and at least 213.36 centimeters of clearance maintained.

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Stringing and Removing Conductors 1.

Purpose

1.1

The purpose of this procedure is to establish safety requirements for stringing and removing electrical conductors.

2.

Requirements

2.1.

In addition to the following safety requirements, TVA Safety Procedure 1109, “Protective Grounding” shall also apply to conductor stringing and removal work.

2.2.

The tension stringing method, barriers, or clearance poles shall be used to minimize the possibility that conductors and cables being installed or removed will contact energized powerlines or equipment.

2.3.

The protective measures required by TVA Safety Procedure 1201, paragraph 2.19 for mechanical equipment shall also be provided for conductors, cables, and pulling and tensioning equipment when the conductor or cable is being installed or removed close enough to the energized conductors that any of the following failures could energize the pulling or tensioning equipment or the wire or cable being installed or removed. •

Failure of the pulling or tensioning equipment.

•

Failure of the wire or cable being pulled.

•

Failure of the previously installed lines or equipment.

2.4.

Reel handling equipment, including pulling and tensioning devices, shall be in safe operating condition, leveled, aligned, and anchored.

2.5.

Load ratings of stringing lines shall not be exceeded.

2.6.

Pulling and tensioning devices, shall be in safe operating condition, leveled, aligned, and anchored.

2.7.

Pulling lines and accessories shall be repaired or replaced when defective.

2.8.

Conductor grips shall not be used on wire rope unless the grip is specifically designed for this application.

2.9.

Reliable communications, through 2-way radios or other equivalent means, shall be maintained between the reel tender and the pulling rig operator.

2.10.

The pulling rig shall only be operated when it is safe to do so. Examples of unsafe conditions include employees in locations prohibited by requirement 2.11, conductor and pulling line hang-ups, slipping of the conductor grip, and loss of communications.

2.11. While the conductor or pulling line is being pulled (in motion) with a power-driven device, employees shall not be directly under overhead operations or on the crossarm. 2.12.

When stringing or removing conductors parallel to or crossing energized circuits or apparatus, proper grounding procedures shall be followed on the new conductor for protection against static or induced voltages and accidental contacts with energized circuits. When conductor is in motion, this can be accomplished by grounding the

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stringing block. Before removing the conductor from the grounded block, install grounds on the conductor with a hotstick. 2.13. Tape shall not be used to reinforce cotter pins on stringing blocks. Defective cotter pins shall be replaced. 2.14. Tensioners and pullers shall be adequately grounded and anchored in such a manner that during pulling, slacking, or sagging, the equipment will not move from its position. 2.15. Communication shall be established and maintained between employees controlling the stringing operation. If communication is lost, the stringing operation shall be stopped. 2.16.

Protection shall be verified and a caution order obtained on all energized circuits or apparatus being crossed by conductor-stringing or removal operations.

2.17.

When conductors parallel to an energized circuit are being strung or removed, care should be taken to keep the conductor from becoming fouled in trees, bushes, crossarms, or other objects. If the conductor becomes fouled, the pulling operation should be stopped immediately and the tension on the conductor should be relieved before any attempt is made to clear it.

2.18. Conductors being strung or removed should be kept clear of sidewalks, driveways, alleys, streets, highways, and railroad tracks if possible. When this is not possible, employees should be stationed to stop or reroute vehicles and pedestrians. 2.19.

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Conductors should not be attached to or removed from a structure until it is reasonably certain that the structure will withstand the altered strain.

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Part III: Worker Safety Rules

Transmission Line Work 1.

Purpose

1.1

The purpose of this procedure is to establish safety requirements for transmission line work, including handling and climbing poles.

2.

General Requirements

2.1.

No employee shall be under a tower or structure while work is in progress, except when such a working position is necessary to assist employees working above.

2.2.

Tag lines or other similar devices shall be used to maintain control of tower sections being raised or positioned unless the use of such devices would create a greater hazard.

2.3.

The loadline shall not be detached from a member or section until the load is safely secured.

2.4.

Work shall be discontinued when adverse weather conditions make the work too hazardous. Thunderstorms in the immediate vicinity, high winds, snow storms, and ice storms are examples of adverse weather conditions that make this work too hazardous to perform, except under emergency conditions where special precautions are taken to protect the employees.

2.5.

Before work is begun in the vicinity of vehicular or pedestrian traffic that may endanger employees, warning signs or flags and other traffic control devices shall be placed to alert and channel approaching traffic. Where additional employee protection is necessary, barricades shall be used. At night, warning lights shall be prominently displayed.

2.6.

A safe means of passage shall be provided for employees crossing streams or other bodies of water.

2.7.

When a pole is set, moved, or removed near an exposed energized overhead conductor, each employee shall use insulated devices when handling the pole and not contact the pole with uninsulated parts of his or her body.

2.8.

Before structures, such as poles or towers, are subjected to the stresses of climbing or the installation or removal of equipment, it shall be determined, i.e., "sounding" or "probing", that the structures are capable of sustaining the additional or unbalanced stresses. If the pole or other structure cannot withstand the loads that will be imposed, it shall be braced or otherwise supported to prevent failure.

2.9.

Pole holes shall be attended or physically guarded whenever anyone is working nearby.

2.10

Fall protection shall be used by employees working at elevated locations more than 1.2 meters above the ground on towers or similar structures. While climbing or relocating on towers or similar structures, fall protection is not required for qualified employees. Upon reaching the work location, fall protection is required. If conditions such as ice, high wind, the design of the structure for example, no provision for holding on with hands, or contaminates prevent the climber from climbing safely, fall protection is required.

2.11. The "free" walking of horizontal members, i.e., no hand holds, is prohibited.

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2.12. Workers shall not attach conductors to their belts or hold them in their hands while climbing. They shall use a hand-line to raise or lower conductors on a structure after they reach their work position. 2.13.

Equipment operators shall take movement signals only from the designated person. The operators shall obey a stop signal from anyone.

2.14. Ropes or lines used in handling loads shall not be wrapped around workers’ bodies. 2.15.

Suspension insulators shall not be climbed.

2.16.

Before performing switching on a line switch, the switch grounding plate shall be clean and properly positioned.

2.17. The switch grounding plate conductor connections and the switch rod grounding braid connections shall be inspected for tightness and found in good condition before performing switching. 2.18.

When operating an air break line switch, the operator shall position both feet firmly on the switch grounding plate and maintain this contact throughout the switching process, touching only the switch handle.

2.19. When starting to pull a pole, the pole should be "loosened" by using a winch, pole jack, auger, bulldozer or other method before the pole is lifted by a crane. 2.20.

Before leaving the ground, the employee should survey the work to be done and determine the best position to use on the structure to perform the work.

2.21. Avoid unnecessary conversation while ascending or descending a structure. 2.22.

Any employee is responsible for signaling an equipment operator to stop when they think there is imminent danger.

2.23.

All equipment used in rigging should be of an approved type or fabricated according to accepted industry practices.

2.24.

Any employee shall warn other employees of unsafe rigging practices they observe.

2.25. Workers shall not work directly beneath other employees unless it is absolutely necessary. 2.26. The area immediately under the structure should be kept uncluttered. 2.27.

Side guys used in installing structures should be attached to substantial objects.

2.28. Tools and material should not be thrown or dropped from structures. 2.29. Workers should stand clear of loaded winch cables, making sure they are not in the bight of the cable. 3.

Pole Handling General

3.1.

Clearance poles and arms shall have balance point and 10-foot butt mark readily visible.

3.2.

Before loading or unloading is begun, the wheels of the transporting vehicle shall be blocked or securely braked.

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3.3.

Before unloading poles from a railroad car, the brakes shall be set and the wheels chocked.

3.4.

Reflectors shall be installed on clearance poles adjacent to roadways.

3.5.

Poles loaded on trailers shall be securely bound to the trailers before towing. A minimum of two tied-owns, plus a tie-down for each additional 3meters of load, are required.

3.6.

When traveling on public roads, the trailing end of a load of poles shall be marked by a red flag during the day and a red light at night.

3.7.

Employees shall not remain on a pole pile or trailer when a pole is being loaded or unloaded.

3.8.

Chokers, wire rope, or other rigging hardware used to lift poles shall be of adequate size, type, condition, and arrangement to safely handle the load. (See TVA Safety Procedure 1607.)

3.9.

Only ratchet-type load binders shall be used.

3.10. When poles are being handled, they shall be controlled by tag lines, butt ropes, cant hooks, or cant straps, as appropriate. 3.11.

Concrete poles shall be lifted only from the manufacturer-designed lifting points.

3.12. Braided nylon slings or nylon chokers of adequate size shall be used when lifting concrete poles. Wire rope choker shall not be used on concrete poles. 3.13.

Poles placed on piles shall be securely blocked or secured to prevent rolling or shifting.

3.14.

Load binders shall not be released with employees standing on the load of poles unless other means have been used to secure the load.

3.15.

Employees and equipment should be placed so as to minimize the danger of injury or damage should a pole or poles get out of control.

3.16.

Poles should be removed from storage in such a manner as to leave the pile in a safe condition. Storage piles should be rearranged after the removal, if necessary, to avoid possible shifting.

3.17.

Employees, while handling poles, should wear suitable clothing and gloves to protect against creosote burns and splinters.

3.18. Poles should not be stored under energized conductors. 3.19.

Employees should not needlessly climb on top of pole piles.

3.20. If possible, load binders should be installed so that they can be operated from the ground. 3.21. Where practical, employees should work on the uphill side of the poles. 4.

Working on Wood Poles

4.1.

When poles are being handled, they shall be controlled by tag lines, butt ropes, or cant hooks.

4.2.

When wood poles are being set or removed in proximity to live-line conductors: •

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They shall not be allowed to contact live conductors.

4.3.

Body belts and safety straps shall be used when working off the ground on poles or wooden structures.

4.4.

Climber gaffs less than 3.2 cm in length shall not be used.

4.5.

Poles shall be "HITCH-HIKED" up and down except when moving around crossarms or other obstructions.

4.6.

Climber straps and gaffs shall be inspected before use, maintained in good condition, and stored with gaff protectors in place.

4.7.

Workers should not be on poles that are being plumbed or canted.

4.8.

When climbing poles, use care to set gaffs securely in the pole and avoid cracks, knots, holes, nails, and pole attachments.

4.9

When an old pole is being replaced with a new pole, employees should work from the new pole whenever possible.

4.10

When climbing trees, workers should not rely on dead limbs for support. They should not let bark build up under the gaffs.

5.

Working on Steel Poles and Towers

5.1.

When steel poles are being handled, they shall be controlled by tag lines, butt ropes, or canting devices.

5.2.

Body belts and safety straps or lanyards shall be used when work is being done off the ground.

5.3.

Safety strap snap-ends shall be fastened in a D-ring on the body belt while the safety strap is not in use.

5.4.

Prior to setting steel poles, step-bolts shall not be installed from the point of crane attachment to approximately 4.6 meters above point of attachment to provide headroom for crane boom.

5.5.

Prior to lifting a steel pole, all slip-joints below the crane attachment point shall be securely lashed to prevent any possibility of separation during lifting.

5.6.

Fiberglass pole cant with straps shall be used to cant steel poles in the vicinity of energized lines or equipment.

5.7.

The bottom 10 step-bolts shall be removed before leaving the site.

5.8.

Temporary step-bolts shall be properly attached.

6.

Working on Concrete Poles

6.1.

When concrete poles are being handled, they shall be controlled by tag lines, butt ropes, or canting devices.

6.2.

Concrete poles shall be lifted only from the manufacturer-designed lifting points.

6.3.

Braided nylon slings or nylon chokers shall be used when lifting concrete poles. Wire rope chokers shall not be used on concrete poles.

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6.4.

Prior to setting concrete poles, step-bolts shall not be installed from the point of crane attachment to approximately 4.6 meters above point of attachment to provide headroom for crane boom.

6.5.

The bottom 10 step-bolts shall be removed before leaving the site.

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Right of Way Clearing and Grounds Maintenance 1.

Purpose

1.1

The purpose of this procedure is to establish requirements for right of way clearing and grounds maintenance.

2.

Farm Tractor and Bushhog

2.1.

The operator and crew members shall wear safety goggles or other appropriate eye protection and protective headgear while working with this equipment.

2.2.

Roll bars shall be installed on the tractor and the seat belt used.

2.3.

Before this equipment is transported on trucks or trailers, it shall be tied down (TVA Safety Procedure 1201, paragraph 4.3) and the trailer brakes checked for proper operation.

2.4.

Do not allow unauthorized persons near the equipment while it is being operated.

3.

Chain Saw Operation

3.1.

The majority of chainsaw injuries are caused by kickback. Most kickbacks occur when the top or nose of the moving chain hits an obstruction. As a result, the chain saw is often thrust toward the operator’s face. To prevent kickback, make certain there are no obstructions which will come into contact with the nose of the bar. The anti-kickback chain will cut as well as the standard chain and will help reduce the force of any kickback.

3.2.

Only employees trained in the use of chain saws shall be allowed to operate chain saws.

3.3.

PPE shall be visually inspected prior to use and unserviceable PPE shall be discarded or repaired.

3.4.

Anti-kickback chains shall be used.

3.5.

Each chain saw shall be equipped with a chain brake.

3.6.

Use approved safety cans, properly labeled, for mixed gasoline.

3.7.

Operators shall wear appropriate eye protection, gloves and foot protection while operating chain saws. NOTE: Minimum footwear permitted for PSO chain saw operations shall be: heavy duty footwear constructed with cut-resistant material, water resistant, and providing ankle support. Reference 29 CFR 1910.266.

3.8.

Operators shall use appropriate protective chaps during any use of a chain saw except when working off the ground.

3.9.

Tree felling or limbing shall always be preceded by an evaluation of tree lean, dead limbs, vines, or other conditions which affect the safety of personnel.

3.10. When felling trees, select a clear path of retreat to be used when the tree is falling. 3.11. If a tree accidentally is cut or falls into a powerline, no contact shall be made with the tree until the line is de-energized, tagged, and grounded under a Hold Order clearance, unless approved hot-line techniques are used. III-269

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Extreme caution shall be used when cutting dead trees or trees adjacent to dead trees.

3.13. Chain saw operators shall inspect the saw prior to operating to determine that all handles, guards, and brakes are in place and tight, all controls function properly, and that the muffler is operative. 3.14.

Chain saw operators shall follow manufacturer’s instructions as to operation and maintenance of the saw.

3.15.

Chain saws shall be fueled in safe areas and not under conditions conducive to fire such as near people smoking, hot engines, directly under powerlines, etc.

3.16.

Chain saws shall be started at least 3 meters away from fueling area.

3.17. Chain saw operators shall be certain of their footing and clear away brush which might interfere before starting to cut. 3.18.

Chain saw engine fuel shall not be used for starting fires or as a cleaning solvent.

3.19.

A chain saw shall have its brake on or be cut off when the operator carries it for a distance greater than from tree to tree or in hazardous conditions such as slippery surfaces or heavy underbrush. The saw shall be at idle speed when carried short distances.

3.20.

Chain saws shall be carried by their handle bar and in a manner to prevent contact with the chain and muffler.

3.21. Chain saw operators shall not use the saw to cut directly overhead or at a distance that would require the operator to relinquish a safe grip on the saw. 3.22.

Each chain saw weighing more than 6.8 kilograms, service weight, that is used in trees shall be supported by a separate line, except when work is performed from an aerial lift and except during topping or removing operations where no supporting limb will be available.

3.23. Each chain saw shall be equipped with a control that will return the saw to idling speed when released. 3.24. Each chain saw shall be equipped with a clutch and shall be so adjusted that the clutch will not engage the chain drive at idling speed. 3.25.

A chain saw shall be started on the ground or where it is otherwise firmly supported. Drop starting of saws over 6.8 kg is permitted outside the bucket of an aerial lift only if the area below the lift is clear of employees and equipment.

3.26.

A chain saw engine shall be started and operated only when all employees other than the operator are clear of the saw.

3.27. A chain saw shall not be running when the saw is being carried up into a tree by an employee. 3.28. Chain saw engines shall be stopped for all cleaning, refueling, adjustments, and repairs to the saw or engine, except as the manufacturer’s servicing procedures require otherwise. 3.29. Carry the saw with the blade toward the rear so the chain will not become snagged in the underbrush. 3.30. III-270

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When operating a saw, keep both hands firmly on the saw, one on the handlebar, and the other on the handgrip.

3.32. Wear protective headgear and heavy nonslip shoes. Never wear loose-fitting gloves and shirts. Keep shirt buttoned and tucked in. 3.33.

Be sure of your balance at all times. When starting a cut, always place the spikes against the wood before engaging the chain.

3.34.

When climbing trees, workers should not rely on dead limbs for support. They should not let bark build up under the gaffs.

3.35.

Tag lines should be used when necessary to assist the operator to control the direction in which the tree falls.

3.36. Be sure the muffler and exhaust system are in good condition. 3.37.

Before saws are transported in a truck, they should be placed in boxes, cases, or otherwise secured for protection of crew members.

3.38. Operators should wear approved hearing protection to guard against sustained high-level noise. Protective headgear with attached hearing protectors and face screen should be worn. 4.

Power Mower Operation

4.1.

Do not tamper with the blade while the mower is running.

4.2.

Disable the mower engine before inspecting, adjusting, or changing attachments.

4.3.

Fill the fuel tank outdoors or in well-ventilated areas.

4.4.

Do not fill the fuel tank while the engine is running or while it is still hot.

4.5.

No smoking is permitted while filling the fuel tank.

4.6.

Use approved and properly labeled safety cans for fuel.

4.7.

Fuel should not be transferred from one vessel to another in the vicinity of energized high-voltage equipment.

4.8.

Gloves should be worn when handling mower blades.

4.9.

When making carburetor adjustments, stand to one side and keep hands and feet in the clear.

4.10.

Keep feet away from the blade when starting the mower.

4.11.

On mowers so equipped, the blade should not be engaged until ready to begin mowing.

4.12. Always stop the engine when it is necessary to leave the mower. 4.13. Skid boards or a hydraulic lift tailgate should be used in loading and unloading the mower. 4.14.

The operator should keep the area of mowing operation clear of unnecessary persons.

4.15.

The mower discharge chute should be directed away from persons.

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4.16. Sloping or uneven terrain should be mowed horizontally with walking-type mowers if practical. 4.17. Riding-type mowers should not be used on steep terrain. 4.18. Mowers should not be used without proper guarding and operating interlock devices in place. 5.

Shear Clearing

5.1

The bulldozer shall be equipped with roll bars and the seat belt shall be worn.

6.

Hand Clearing

6.1.

Kaiser blades, brush hooks, axes, and other sharp tools shall be transported and stored in designated places.

6.2.

"Cut" resistant gloves shall be used when sharpening or repairing bladed tools.

6.3.

File guards shall be used when sharpening tools.

6.4.

Axes and brush hooks shall be secured while being sharpened.

7.

Brush Chipper

7.1.

Hearing and eye protection (face shields, goggles, or safety glasses with sideshields) and gloves shall be worn while feeding brush into a chipper.

7.2.

Stop the engine and cutters before inspecting the discharge chute or cutters.

7.3.

Loose clothing, rings, watches, and bracelets shall not be worn when working with the brush chipper.

7.4.

Brush chippers shall be equipped with a locking device in the ignition system.

7.5.

Access panels for maintenance and adjustment of the chipper blades and associated drive train shall be in place and secure during operation of the equipment.

7.6.

Trailer chippers detached from trucks shall be chocked or otherwise secured.

7.7.

Each employee in the immediate area of an operating chipper feed table shall wear protective eyewear.

7.8.

Feed the large diameter end of brush into the chipper first.

7.9.

Keep the protective flaps at the throat of the cutter in good condition.

8.

Weed and Brush Trimmers

8.1.

Eye protection (face shields, goggles, or safety glasses with sideshields) shall be worn when using trimmers. Hearing protection shall be worn as recommended by the trimmer manufacturer.

8.2.

High top shoes or shin guards shall be worn when using trimmers.

8.3.

Properly sized string or blades shall be used.

8.4.

Trimmers shall not be used unless equipped with properly installed guards.

8.5.

When an employee is using a motor-operated, blade-type brush trimmer, all other employees shall stay at least 3 meters away.

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8.6.

Employees should stand to the side of, rather than directly behind, when feeding brush into the chipper.

9.

Chemical Clearing and Maintenance

9.1.

Before using chemicals for vegetation control, read and follow the manufacturer’s directions on the container labels and observe the precaution identified in the Material Safety Data Sheets (MSDS).

9.2.

Avoid unnecessary contact of chemical mixture with skin and clothing.

9.3.

Wear appropriate protective clothing as required. When mixing chemicals, neoprene gloves, long sleeve shirts, and eye protection should be worn.

9.4.

Hands should be washed prior to eating or use of tobacco products when using chemicals for vegetation control.

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Annex L Specifications and Drawings for Underground Electric Distribution The following materials have been obtained from U.S. Department of Agriculture Rural Utilities Service RUS Bulletin 1728F-806 (D-806), June 2000.

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RUS Bulletin 1728F-806 Viewing Instructions There are both bookmarks and links imbedded in this file.

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General information: You can use the buttons at the top of the screen for going from page to page. Also, by rightclicking your mouse, you will see a navigation box. For details, please see the Acrobat Reader help screens.

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TABLE OF CONTENTS 1. General............................................................................................................................... III-283 2. Storage of Material and Equipment ................................................................................... III-283 3. Handling of Cable .............................................................................................................. III-283 4. Plowing .............................................................................................................................. III-284 5. Special Requirements for Coordination Between Owner and Contractor Where Cable is to be Installed by Plowing ..................................................... III-285 6. Trenching ......................................................................................................................... III-285 7. Installing Cable in Trench..................................................................................................III-286 8. Minimum Bending Radius of Cable ................................................................................ III-286 9. Conduit............................................................................................................................. III-287 10. Tagging of Cables at Termination Points ....................................................................... III-287 11. Splices ............................................................................................................................. III-287 12. Primary Cable Termination and Stress Cones ................................................................ III-287 13. Special Precautions for Cable Splices and Terminations ............................................... III-287 14. Secondary and Service Connections............................................................................... III-288 15. Pedestals.......................................................................................................................... III-288 16. Inspection and Inventory of Buried Units....................................................................... III-288 17. Backfilling....................................................................................................................... III-288 18. Equipment Pads .............................................................................................................. III-289 19. Transformers ................................................................................................................... III-289 20. Equipment Enclosures .................................................................................................... III-289 21. Utility Safety Signs ......................................................................................................... III-289 22. Sacrificial Anodes .......................................................................................................... III-289 23. Grounding ....................................................................................................................... III-290 24. Cable Location Markers................................................................................................. III-290 25. Installed Cable and Acceptance Tests............................................................................. III-290 Attachment A: Index of Drawings........................................................................................ III-292 Attachment B: Construction Drawings................................................................................. III-296 INDEX: ASSEMBLIES: Underground Distribution – Bul. 1728F-806 SPECIFICATIONS AND STANDARDS: Construction Specifications and Drawings – Bul. 1728F-806 Underground Electric Distribution – Bul. 1728F-806 UNDERGROUND DISTRIBUTION: Underground Rural Distribution – Bul. 1728F-806

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GENERAL

1.1 These specifications provide for the construction of underground distribution power facilities as specified by the owner. The owner is the organization contracting for the services and, when used in connection with RUS financed facilities, is synonymous with the term borrower as defined in §1710.2. 1.2 It is the responsibility of the borrower to ensure that all construction work shall be accomplished in a thorough and workmanlike manner in accordance with the staking sheets, plans and specifications, and the construction drawings. 1.3 If construction work is performed by the Owner's force account crews instead of a contractor, any reference to "Contractor" apply to the force account crews. 1.4 The provisions of section §1724.50, Compliance with National Electrical Safety Code (NESC) apply to all borrower electric system facilities regardless of the source of financing. a.

A borrower must ensure that its electric system, including all electric distribution, transmission, and generating facilities, is designed, constructed, operated, and maintained in accordance with all applicable provisions of the most current and accepted criteria of the NESC and all applicable and current electrical and safety requirements of any State or local government entity. Copies of the NESC may be obtained from the Institute of Electrical and Electronic Engineers, Inc., 345 East 47th Street, New York, New York 10017-2394. This requirement applies to the borrower’s electric system regardless of the source of financing.

b.

Any electrical standard requirements established by RUS are in addition to, and not in substitution for or a modification of, the most current and accepted criteria of the NESC and any applicable electrical or safety requirements of any State or local governmental entity.

c.

Overhead distribution circuits shall be constructed with not less than the Grade C strength requirements as described in Section 26, Strength Requirements, of the NESC when subjected to the loads specified in NESC Section 25, Loadings for Grades B and C. Overhead transmission circuits shall be constructed with not less than the Grade B strength requirements as described in NESC Section 26.

2. STORAGE OF MATERIAL AND EQUIPMENT: It is the responsibility of the borrower to ensure that all material and equipment to be used in construction must be stored so as to be protected from deteriorating effects of the elements. If outdoor storage cannot be avoided, the material and equipment must be stacked on supports well above the ground line and protected from the elements as appropriate, and with due regard to public safety. Bulletin 1728F-806 Page 2 3. HANDLING OF CABLE: It is the responsibility of the borrower to ensure that the cable shall be handled carefully at all times to avoid damage, and shall not be dragged across the

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ground, fences or sharp projections. Care shall be exercised to avoid excessive bending of the cable. The borrower shall ensure that the ends of the cable be sealed at all times against moisture with suitable end caps. Where it is necessary to cut the cable, the ends will be terminated or sealed immediately after the cutting operation. 4. PLOWING 4.1 When cables are to be installed by plowing, it is the responsibility of the borrower to ensure that the plowing equipment be subject to the approval of the Owner and the public authorities having jurisdiction over highway and road rights-of-way. The plow must be provided with a means to assure positive holddown of the plow blade to provide proper depth at all times. 4.2 The design of the plowshare must ensure that the cable passing through the plow will not be bent in a radius less than 12 times the outside diameter of the cable. The equipment must be capable of extending the plow a minimum of 15.24 centimeters below the specified depth under all terrain conditions of plow utilization. 4.3 The borrower must ensure that equipment and construction methods used during construction cause minimum displacement of the soil. The slot made in the soil by the cable plows must be closed immediately by driving a vehicle track or wheel over the slot or by other suitable means. 4.4 Starting and terminating points of the plowing operation must be excavated prior to cable installation to reduce possible cable damage and to assure sufficient burial depth. 4.5 During the plowing operation, care is to be exercised to feed the cable or wire into the ground through the plow loosely and at minimum tension. Besides using proper equipment and construction methods, supervision by the borrower or the borrower’s representative shall be furnished at all times at the site of plowing operations to assure compliance with these specifications. 4.6 If, during the plowing operation, the plow should strike a buried object or rock that would stop the equipment and necessitate removal of the plow from the ground, the plow must be removed from the ground carefully and, if practical, without backing the plow. If it should be necessary to back the plow to remove it from the ground, the cable must be uncovered a sufficient distance back for inspection by the Owner to determine whether the cable or wire has been damaged. 4.7 The cable must be inspected carefully as it is payed out from the reel to be certain that it is free from visible defects. Every instance of damaged cable observed at any time, whether prior to installation, during installation, or when discovered by test or observation subsequent to installation in plant, shall be immediately called to the attention of the Owner. Repair or correction of such damage must be completed promptly and in accordance with the written instruction of the Owner. The location of any such repair must be indicated on the staking sheet.

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5. SPECIAL REQUIREMENTS FOR COORDINATION BETWEEN OWNER AND CONTRACTOR WHERE CABLE IS TO BE INSTALLED BY PLOWING 5.1 It is the responsibility of the borrower to ensure that the Contractor and the Owner shall jointly review the staking sheets prior to the start of construction. At that time, the Contractor shall propose any desirable changes or clarifications. These changes, if approved by the Owner, shall be made and recorded on the staking sheets. No changes on the staking sheets shall be made by the Contractor without the prior written approval of the Owner. A representative of the Owner shall remain in the immediate vicinity of the plowing operations at all times and shall consider and possibly approve any acceptable changes proposed by the Contractor. A representative of the Owner shall also inspect any damage to cable and approve acceptable methods of repair or correction of such damage in accordance with the provisions of these specifications. 5.2 In the event that rock is encountered during the plowing operation so that the buried cable cannot be installed to the required minimum depths in soil, the Contractor shall determine for the Owner the nature and extent of the rock encountered. Based on this information, the Owner shall determine whether the cable is to be rerouted, trenched in rock or a change made to aerial construction. This decision shall be made promptly, and appropriate changes in units shall be made on the staking sheets. Such changes shall be in writing, dated, and initialed by the Owner. 5.3 Due to the necessity of making on-the-spot corrections and changes on staking sheets, it may not be possible for the Owner to issue revised staking sheets to the Contractor in all cases. When changes are made, dated, and initialed by the Owner on a set of the Contractor's staking sheets, it shall be the Contractor's responsibility to transfer these changes to all other sets of staking sheets being used by the Contractor for construction purposes. 5.4 The Contractor shall provide a competent representative to work with the Owner on the inventory and inspection of buried cable units. The inventory of buried cable will be made as soon after the plowing operation as practical to avoid later disagreements on the quantity of cable installed when changes are required in the project. 6.

TRENCHING

6.1 It is the responsibility of the borrower to ensure that all trenching depths specified are minimum as measured from the final grade to the top surface of the cable. The routing must be as shown on the staking sheets and plans and specifications unless conditions encountered are such that changes are necessary to accomplish the work. In such event, the Owner shall be notified promptly. If rock or other difficult digging is involved, the Contractor shall determine the nature and extent of the difficulty, and the Owner shall determine whether rerouting, rock trenching, plowing or other changes are necessary. Loose soil or crumbly rock shall not be considered as "difficult digging." The trench widths specified are minimum and should be increased as necessary to obtain the required depths in loose soils. 6.2 Where trenches are intended for more than one cable, particular care must be taken to provide for extra depth and width to allow for soil falling into the trench during the laying of the first cables.

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6.3 Care shall be exercised to minimize the likelihood of waterflow since this may cause trench damage and reduction in trench depth. If this occurs, the trench must be cleared to the specified depth before installing the cable. 6.4 All trenches must follow straight lines between staked points to the greatest extent possible. Secondary and service trenches must extend in a straight line from takeoff points wherever possible. The trenches must be dug so that the bottom has a smooth grade. Large rocks, stones and gravel in excess of 2.53 centimeters must be removed from the bottom of the trench. Where this cannot be accomplished, a 5.08 centimeter bed of sand or clean soil must be placed in the bottom of the trench. 6.5 Construction shall be arranged so that trenches may be left open for the shortest practical time to avoid creating a hazard to the public and to minimize the likelihood of collapse of the trench due to other construction activity, rain, accumulation of water in the trench, etc. 7.

INSTALLING CABLE IN TRENCH

7.1 It is the responsibility of the borrower to ensure that the cable must be placed in the trench as soon after the trenching operation as feasible. Wherever possible, cable must be payed out from the reel mounted on a moving vehicle or trailer. The reel must be supported so that it can turn easily without undue strain on the cable. The cable must be carefully placed in the trench by hand. All cable placement will be done under constant supervision by the borrower or the borrower’s representative who assure that no damage to the cable occurs. 7.2 The cable must be inspected carefully as it is removed from the reel in laying operations to be certain that it is free from visible defects. The Owner shall decide upon corrective action when defects are discovered. 7.3 Where more than one cable is to be placed in a trench, the spacings required by the specifications must be observed. Care must be taken that any soil falling into the trench during the laying of the first cable does not reduce the clearances of the last cable below that specified. Should this occur, the excess soil must be removed carefully by hand or with equipment that will not damage the installed cables. 7.4 Sufficient slack, and in no case less than 60.96 centimeters, must be left at all risers, transformer pads, pedestals and terminal points so that movements of cable after backfilling will not cause damaging strain on the cable or terminals. The cable trench must be mechanically compacted at least 91.44 centimeters from all riser poles, pads, pedestals and terminal points. 7.5 The ends of all secondary cable terminated below ground must be long enough to reach at least 30.48 centimeters above the top of the underground enclosure. 8. MINIMUM BENDING RADIUS OF CABLE: It is the responsibility of the borrower to ensure that the minimum bending radius of primary cable is 12 times the overall diameter of the cable. The minimum bending radius of secondary and service cable is six times the overall diameter of the cable. In all cases the minimum radius specified is measured to the surface of the

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cable on the inside of the bend. Cable bends must not be made within 15.24 centimeters of a cable terminal base. 9. CONDUIT: It is the responsibility of the borrower to ensure that all exposed ends of conduit must be plugged during construction to prevent the entrance of foreign matter and moisture into the conduit. Burrs or sharp projections which might injure the cable must be removed. Riser shield or conduit must extend at least 45.72 centimeters below grade at all riser poles. If full round conduit is used as a riser shield, an end bell must be installed on the lower end to prevent damage to the cable. 10. TAGGING OF CABLES AT TERMINATION POINTS: As the cables are laid, it is the responsibility of the borrower to ensure that they must be identified and tagged. The identification must be of a permanent type, such as that done on plastic or corrosion resistant metal tags. The tag must be securely attached to the cable. Paper or cloth tags are not acceptable. 11.

SPLICES

11.1 It is the responsibility of the borrower to ensure that cable splices must be of the premolded rubber, heat-shrink, or cold-shrink type, of the correct voltage rating and must be installed in accordance with the splice manufacturer's instructions. Splices that depend solely on tape for a moisture barrier must not be used. 11.2 Not more than one splice may be permitted for each 609.6 meters of cable installed unless authorized by the Owner. No bends may be permitted within 30.48 centimeters of the ends of a splice. The cable or circuit numbers and the exact location of all splices must be noted on the staking sheets (as built). 12. PRIMARY CABLE TERMINATION AND STRESS CONES: It is the responsibility of the borrower to ensure that prefabricated stress cones or terminations must be installed in accordance with the manufacturer's instructions at all primary cable terminals. They must be suitable for the size and type of cable that they are used with and for the environment in which they will operate. Any indication of misfit, such as a loose or exceptionally tight fit, must be called to the Owner's attention. The outer conductive surface of the termination must be bonded to the system neutral. A heat-shrink or cold-shrink sleeve must be installed to seal between the body of the termination and the cable jacket. 13. SPECIAL PRECAUTIONS FOR CABLE SPLICES AND TERMINATIONS: It is the responsibility of the borrower to ensure that a portable covering or shelter must be available for use when splices or terminations are being prepared and when prefabricated terminations are being switched. The shelter must be used as necessary to keep rain, snow and windblown dust off the insulating surfaces of these devices. Since cleanliness is essential in the preparation and installation of primary cable fittings, care shall be exercised to prevent the transfer of conducting particles from the hands to insulating surfaces. Mating surfaces must be wiped with a solvent such as denatured alcohol to remove any possible accumulation of dirt, moisture or other conducting materials. A silicone grease or similar lubricant should be applied afterwards in accordance with the manufacturer's recommendations. Whenever prefabricated cable devices are

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opened, the unenergized mating surfaces must be lubricated with silicone grease before the fittings are reconnected. 14.

SECONDARY AND SERVICE CONNECTIONS

14.1 It is the responsibility of the borrower to ensure that a suitable inhibiting compound must be used with all secondary and service connections. 14.2 All secondary cable connections located below grade or in secondary pedestals must be made with pre-insulated secondary connector blocks. Diving bells with open terminals, insulating boots or moisture barriers that depend solely on tape are not acceptable. 14.3 All transformer secondary phase terminal connections must be completely insulated. If the secondary phase terminals are threaded studs, the connection must be made with a preinsulated secondary transformer connection block. If the transformer secondary phase terminals are insulated cable leads, connection must be made with a pre-insulated secondary connector block or with a secondary prefabricated splice when the transformer leads continue directly to the service. 14.4 If a transformer is so large that it must have secondary spades, the spades must be taped or otherwise insulated. Boots used for insulation must be taped so that they cannot be readily slipped off. 14.5 Secondary connections to terminals of pole-mounted transformers must be made so that moisture cannot get inside the cable insulation. This may be accomplished by covering the terminals and bare conductor ends with an appropriate moisture sealant or providing a drip loop. 14.6 The secondary connections and insulation must have accommodations for all future and existing services as shown on the plans and specifications. 15. PEDESTALS: Where required, it is the responsibility of the borrower to ensure that pedestal stakes must be driven vertically into the bottom of the trench before cables are placed, and shall be located as shown on the staking sheets. Pedestal posts and supporting stakes must be in place before the cable is installed. All pedestals should be approximately at the same height above finished grade. 16. INSPECTION AND INVENTORY OF BURIED UNITS: Before any backfilling operations are begun, it is the responsibility of the borrower to ensure that the Contractor and Owner shall jointly inspect all trenches, cable placement, risers, pedestal stakes, and other construction that will not be accessible after backfilling, and an inventory of units shall be taken. If corrections are required, a second inspection shall be made after completion of the changes. 17.

BACKFILLING

17.1 It is the responsibility of the borrower to ensure that the first 15.24 centimeters of trench backfill shall be free from rock, gravel or other material which might damage the cable jacket. In

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lieu of cleaning the trench, the Contractor may, at the Contractor's option, place a 5.08 centimeters bed of clean sand or soil under the cable and 10.16 centimeters of clean soil above the cable. Cleaned soil backfill when used shall contain no solid material larger than 2.54 centimeters. This soil layer must be carefully compacted so that the cable will not be damaged. 17.2 Backfilling must be completed in such a manner that voids will be minimized. Excess soil must be piled on top and must be well tamped. All rock and debris must be removed from the site, and any damage to the premises repaired immediately. 17.3 Pieces of scrap cable or other material remaining after installation must not be buried in the trench as a means of disposal. 18. EQUIPMENT PADS: It is the responsibility of the borrower to ensure that the site for the pad shall be on undisturbed earth adjacent to but not over the trench. The site shall be cleared of all debris and excavated to the specified depth. Gravel or sand may be added to the site and thoroughly compacted. The pad shall be installed level at the specified elevation. 19. TRANSFORMERS: It is the responsibility of the borrower to ensure that transformers shall be handled carefully to avoid damage to the finish and shall be positioned in accordance with the staking sheets and the plans and specifications. Only qualified and experienced personnel shall be allowed to make connections and cable terminations. 20. EQUIPMENT ENCLOSURES: It is the responsibility of the borrower to ensure that excavations for sleeve-type transformer pads and other below-grade enclosures shall be made so as to disturb the surrounding earth as little as practical. Enclosures shall be installed with side walls plumb. When enclosures are of fiber, plastic, or other semiflexible material, backfilling should be done with covers in place and with careful tamping so as to avoid distortion of the enclosure. When installation is complete, the cover of the enclosure shall not be lower than and not more than 5.08 centimters higher than the grade specified by the Owner. Soil in the immediate vicinity shall be tamped and sloped away from the enclosure. At the Owner's option, the excess soil shall be removed from the site or spread evenly over the surface of the ground to the satisfaction of the Owner. 21. UTILITY SAFETY SIGNS: It is the responsibility of the borrower to ensure that utility safety signs must be in accordance with ANSI Z535.2, Environmental and Facility Safety Signs, and shall be applied in accordance with RUS drawings. Copies of the ANSI Z535.2 may be obtained from the National Electrical Manufacturers Association (NEMA), 1300 North 17th Street, Suite 1847, Rosslyn, Virginia 22209. 22. SACRIFICIAL ANODES: It is the responsibility of the borrower to ensure that sacrificial anodes specified shall be installed with backfill package intact and connecting leads positioned for proper connection after the equipment is in place. Anodes shall neither be moved, positioned, lifted, nor lowered into place by pulling on the connecting leads.

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GROUNDING

23.1 It is the responsibility of the borrower to ensure that all neutral conductors, grounding electrodes, sacrificial anodes and groundable parts of equipment shall be interconnected. All interconnections shall be made as shown on the construction drawings. A copper-clad or galvanized steel ground rod with minimum length of 2.44 meters shall be installed at all equipment locations as shown in the construction drawings and at all cable splices and taps. 23.2 All pad-mounted equipment enclosures, including transformers, shall be grounded in such a manner that two separate grounding paths exist between the enclosure and the grounding rod(s). 24. CABLE LOCATION MARKERS: It is the responsibility of the borrower to ensure that location of permanent cable markers shall be as shown on the staking sheets. 25.

INSTALLED CABLE AND ACCEPTANCE TESTS

25.1

It is the responsibility of the borrower to ensure that: a. Continuity: After installation of the cable and prior to the high potential test specified below, authorized personnel shall perform a simple continuity test on the system. This can easily be accomplished by grounding the conductor at the source and checking for continuity from the end of each tap with an ohmmeter or with a battery and ammeter. b. High Potential: After successful continuity tests, authorized personnel should perform high potential tests on each length of cable, with terminations in place but disconnected from the system.

25.2 The installation shall withstand for a minimum of 15 minutes a DC test potential as follows: Primary URD Cable (XLP-TR, and EPR)

Rated Voltage 15 kV 25 kV 25 kV

Insulation Thickness Millimeters

Field DC Acceptance Test Voltage

5.59 6.60 8.76

64.0 kV 80.0 kV 100.0 kV

The voltage may either be increased continuously or in steps to the maximum test value: a.

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If increased continuously, the rate of increase of test voltage should be approximately uniform and increasing to maximum voltage in not less than 10 seconds and in not more than approximately 60 seconds.

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Part III: Worker Safety Rules

If applied in steps, the rate of increase of test voltage from one step to the next should be approximately uniform. The duration at each step shall be long enough for the absorption current to attain reasonable stabilization (l minute minimum). Current and voltage readings should be taken at the end of each step duration. The number of steps should be from five to eight.

25.3 Warning: A hazardous voltage may still exist on the cable after the above testing has been completed. Therefore, before handling the cable, it is the responsibility of the borrower to ensure that the conductor shall be grounded to permit any charge to drain to earth.

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Attachment A INDEX OF DRAWINGS Primary Terminal Pole Assemblies: UA1

Single Phase Cable Deadend Terminal Pole

UA2

Single Phase Cable Deadend Terminal Pole

UA3

Single Phase Cable Tangent Terminal Pole

UB1

Vee-Phase Cable Terminal Pole with Cutouts and Crossarm Mounting Arresters

UB2

Vee-Phase Cable Terminal Pole with Cutouts and Bracket Mounting Arresters

UB3

Vee-Phase Cable Terminal Pole without Cutout, with Crossarm Mounting Arresters

UB4

Vee-Phase Cable Terminal Pole without Cutout, with Bracket Mounting Arresters

UC1

Three Phase Cable Terminal Pole with Cutouts and Crossarm Mounting Arresters

UC2

Three Phase Cable Terminal Pole with Cutouts and Bracket Mounting Arresters

UC2-1

Three Phase Cable Deadend Terminal Pole

UC2-2

Three Phase Cable Tangent Terminal Pole

UC5-1

Three Phase Cable Deadend Terminal Pole with Disconnect Switches

UC6-1

Three Phase Cable Tangent Terminal Pole with Disconnect Switches

Transformer Assemblies: UG6, UG6B,

Single Phase Pad-Mounted Transformer (Radial Feed)

UG7, UG7B

Single Phase Pad Mounted Transformer (Loop Feed)

UG17, UG17B

Three Phase Pad Mounted Transformer (Radial Feed)

UG17-2, UG17-2B

Three Phase Pad Mounted Transformer (Loop Feed)

UG17-3, UG17-3B

Three Phase Pad Mounted Loop Feed Transformer with Radial Feed

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Secondary Assemblies: UJ1, UJ2

Secondary Connector Blocks

UK5

Secondary Pedestal Underground Cable

UK6

Secondary Handhole Underground Cable

Pad Assemblies: UM1-5C, UM1-5NC

Pad Assemblies

UM1-6C

Three Phase Transformer Concrete Pads

UM1-7C, UM1-7NC

Ground Sleeve Assembly

Sectionalizing Assemblies: UM3-14

Single Phase Sectionalizing Enclosure

UM3-44, UM3-45

Single Phase Pad Mounted Sectionalizer or Recloser

UM3-46

Three, Single Phase Pad Mounted Reclosers

UM3E

Fuse/Switch Enclosure Installation

UM3E-1, UM3E-2

Single Pole Switching 200 AMP Fuse Enclosure Installation Wiring Diagrams (Single Phase and Two Phase)

UM3E-3

Fuse Enclosure (200 - 600 AMP) Wiring Diagrams (Three Phase)

Secondary Terminal Pole Assemblies: UM5

Secondary Cable Terminal Pole

UM5-6, UM5-6A

Secondary Cable Terminal to Meter Base

Miscellaneous Accessories: UM6-1 – UM6-8

Miscellaneous Accessories

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Regulator Assembly: UM7-1

Single Phase Regulator Assembly with By-Pass Switching Function Underground to Underground

Metering Assemblies: UM8

Meter Installation Underground Source

UM8-2

Meter Pedestal Wood Post

UM8-3 UM8-3A

Trough Type Meter Pedestal

UM8-4, UM8-4A

Meter & Switch Installation Underground Source

UM8-5

Pad Mounted Switch Installation Underground Source

UM8-6

C.T. Meter Installation Single Phase

UM8-7

C.T. Meter Installation Three Phase

Miscellaneous Assemblies: UM9-2

Pad Mounted Switched Capacitor Enclosure

UM12

Cable Route Marker

Corrosion Control Assemblies: UM27-1

Sacrificial Anode for Cable Splice Protection (Bare to Jacketed Cable)

UM27-2

Sacrificial Anode for Equipment Ground Protection

UM27-3

Sacrificial Anode for Cable Ground Protection

UM28

Test Station

Sectionalizing Assembly: UM33

Multi Phase Sectionalizing Enclosure Pad or Sleeve Mounted

Grounding Assemblies: UM48-1

Grounding Assembly for Pad Mounted Single Phase Transformers and Enclosures

UM48-2

Grounding Assembly for Pad Mounted Multi Phase Transformers and Enclosures

UM48-3

Grounding Assembly for Underground Primary Cable

UM48-4

Grounding Assembly for Underground Primary Cable (with Test Station)

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UM48-5

Grounding Grid for Pad Mounted Equipment Installation

UM48-6

Grounding Array for Pad Mounted Equipment Installation

Conduit and Trenching Assemblies: UR2 to UR2-2

Trenches for Direct Burial Cables

UR2-3 to UR2-5

Trenches for Direct Burial Cables

UR2-NT UR2-ST

Trenches for Direct Burial Cables

Guideline Drawings: UX1

Open Delta Connection with Single Phase Pad Mount Transformers

UX2

Single Phase Pad Mounted Transformer Deferred Unit Pedestal Type

UX3

Single Phase Padmounted Transformer Deferred Unit Pad-Sleeve Type

UX4

Installation of Neutral Connection in Above Grade Pedestal

UX5

Sectionalizing Pedestal Grounding

UX7

Location Methods for Below Grade Enclosure

UX8

Temporary Primary or Secondary Cable Termination for Future Use

UX11

Connection of Terminator/Arrester to Overhead Line

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Attachment B

Construction Drawings

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Part IV: Recordkeeping, Training and Inspections, Accident Investigating and Reporting

PART IV. RECORDKEEPING, TRAINING AND INSPECTIONS, ACCIDENT INVESTIGATION AND REPORTING CONTENTS 4(a) Introduction ......................................................................................................................IV-3 4(b) Safety Recordkeeping Practices and Protocols .............................................................IV-3 4(b)(1) Illnesses .....................................................................................................................IV-3 4(b)(2) Injuries .......................................................................................................................IV-4 4(b)(3) Deaths ........................................................................................................................IV-4 4(b)(4) What's Not Recordable ..............................................................................................IV-4 4(b)(5) How to Analyze Injury and Illness Records..............................................................IV-5 4(b)(6) Ensuring Accuracy in Recordkeeping .......................................................................IV-5 4(c) Accident Recordkeeping Forms ......................................................................................IV-6 4(d) Safety Training and Recordkeeping.............................................................................IV-10 4(d)(1) Type of Training......................................................................................................IV-10 4(d)(2) Recordkeeping .........................................................................................................IV-13 4(e) OHSAS 18001 (Occupation Health and Safety Assessment Series)...........................IV-13 4(f) Bibliography ....................................................................................................................IV-15

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4(a) Introduction Occupational injury and illness records have several distinct functions or uses. One use is to provide information to employers whose employees are being injured or made ill by hazards in their workplace. The information in NERC safety records makes employers more aware of the kinds of injuries and illnesses occurring in the workplace and the hazards that cause or contribute to them. When employers analyze and review the information in their records, they can identify and correct hazardous workplace conditions on their own. Injury and illness records are also an essential tool to help employers manage their company health and safety programs effectively. Employees who have information about the occupational injuries and illnesses occurring in their workplace are also better informed about the hazards they face. They are therefore more likely to follow safe work practices and to report workplace hazards to their employers. When employees are aware of workplace hazards and participate in the identification and control of those hazards, the overall level of safety and health in the workplace improves. This Part provides procedures and recommended protocols for documentation, reporting and accident investigations. 4(b) Safety Recordkeeping Practices and Protocols The extent of occupational illness and injury is much greater than government statistics indicate. The problem is recognized in the United States for example. Some U.S. researchers suspect that the number of injuries is twice as great as reported, and the number of illnesses may exceed the number reported by a factor of five. No one really knows. In Nigeria, accident statistics have only recently been recorded in the industry sector and there are no official published values. It's time that we learned the full extent and nature of occupational illness and injury in the Nigerian workforce. The proper compensation for workers with workplace injuries and the direction of research on occupational disease prevention depend on accurate recordkeeping. Employers are required by law to record occupational injuries and illnesses. Records must be kept in the Daily Injury and Illness Log (NERC Accident Statistics Reporting Form provided in Section 4(c)). An annual summary of that form is to be posted by the employer every February for the entire month. Records are to be kept for ten years. Under-reporting of illness and injury may occur if employers aren't aware of the proper reporting procedures, if they misdiagnose conditions, if they fail to inform workers' compensation boards and insurance carriers when an illness/injury has occurred, if they make clerical errors in tabulating records, if they deliberately falsify records, etc. Failure to comply with the recordkeeping regulations can bring stiff fines – up to $10,000 or its equivalent in Naira for a willful violation. What's more, intentional falsification of records is a crime, grounds for a jail term. 4(b)(1) Illnesses NERC requires employers to record any work-related illness that is "diagnosed or recognized." A diagnosis is performed by a physician, registered nurse or someone with training and experience to make a diagnosis. NERC requires employers to record "recognized" (not diagnosed) illnesses IV-3

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because "employers, employees and others may be able to detect some illnesses such as skin diseases or disorders without the benefit of specialized medical training." Recordable illnesses include: • • • • •

skin diseases; lung diseases and other respiratory conditions; poisoning; disorders due to physical agents (such as heat or noise); and disorders associated with repeated trauma (such as carpal tunnel syndrome and tendonitis).

These cases do not require any lost time or medical treatment to be reported, only to be diagnosed or recognized. 4(b)(2) Injuries An injury which involves any of the following must be recorded: • • • • • • •

medical treatment (other than first aid); loss of consciousness; restriction of work motion; transfer to another job; termination of employment; electrical burns; and electrocution.

The distinction between an illness and an injury is not always obvious, but it is important, because all illnesses must be recorded, but some injuries do not need to be recorded. Whether a case is "an injury or an illness is determined by the nature of the original event or exposure which caused the case, not by the resulting condition." Injuries are caused by "instantaneous events." A condition that is caused by anything other than an instantaneous event must be recorded as an illness. "For example, a loss of hearing resulting from an explosion (an instantaneous event) is classified as an injury; the same condition resulting for exposure to industrial noise over a long period of time" must be classified as an illness, which means that it must be recorded even if it does not meet any of the criteria for a recordable injury. 4(b)(3) Deaths Any death of an employee or former employee that occurs as a result of an injury or illness that is recordable must also be recorded. If an employee has a recordable injury or illness and then is terminated or retires, and then dies as a result of the recordable injury or illness, the death must also be recorded. 4(b)(4) What's Not Recordable An injury that requires only first aid, that is, a minor injury that is resolved with one-time treatment (with follow-up for observation only, not additional treatment). A minor injury may be

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treated by a doctor or a nurse, but any injury that must be treated by a doctor or nurse or any injury that requires follow-up medical treatment is not minor, and must be recorded. 4(b)(5) How to Analyze Injury and Illness Records Local unions can analyze the NERC records to see if they are accurate and to pinpoint patterns of disease and injury in the workplace. Here's how: 1. Ask your employer in writing for the NERC Incident Reporting daily log, NOT JUST THE SUMMARY, for the past ten years. The right to review and copy these records is provided by the NERC standard. The log and summary of all recordable occupational injuries and illnesses shall, upon request, be made available by the employer to any employee, former employee, and to their representatives for examination and copying in a reasonable manner and at reasonable times. The employee, former employee, and their representatives shall have access to the log for any establishment in which the employee is or has been employed. 2. Consult people knowledgeable about workers' compensation or insurance problems of the membership, since they know names of individual members who have filed claims which may not be recorded. The failure to list any cases known to the union is a tip-off that something is wrong. 3. Find out what current criteria the employer uses to record occupational illness and injury. This will also provide clues about how the employer interprets the NERC guidelines when filling out the Incident Reporting log. 4. Obtain copies of employee exposure and medical records. Employers must provide this information to union representatives, free of charge, within 15 working days. This includes: • industrial hygiene reports; • biological monitoring; • medical histories and questionnaires*; • results of medical examinations & lab tests*; • medical opinions, diagnoses, & recommendations*; and • worker medical complaints*. * Requires prior written consent from affected employee(s). 4(b)(6) Ensuring Accuracy in Recordkeeping In order to avoid recordkeeping violations, NERC has adopted recognized procedures as a model for reporting injuries and illnesses. These procedures were developed by the U.S. company Chrysler Corporation in response to the record fines levied against them. Whether your employer adopts these guidelines or uses some other set of procedures, the union must actively police them to ensure accurate and complete reporting. The Chrysler procedures are reprinted below: 1. Each patient visiting the plant medical facility to report injuries or signs or symptoms of illnesses will be asked whether their medical condition is caused or aggravated by work. Responses will be recorded. Where the patient states that an injury or illness is work

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2.

3.

4.

5.

6.

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related, and that case otherwise meets the criteria for recording, that case will be entered on the log pending final determination of causality. Injuries and illnesses for which workers' compensation claims are filed will be entered on the Daily Injury and Illness Log pending final determination. A list of claims paid voluntarily or by decisions will be maintained. This list will be available for examination and copying by the union. Sickness and accident claims for which occupational causation is claimed and which come to the attention of plant medical or safety departments will be investigated for occupational causation. Those instances which meet the recording criteria specified in the guidelines will be entered on the injury and illness log. Instances where employees are granted medical restrictions or job transfers as a result of injuries or illnesses claimed to be of occupational origin will be entered on the log pending final determination. A list of such restrictions and transfers will be maintained. This list will be available to the union. Where a case is removed from the log as a result of investigation, the reasons will be documented and the record of the investigation maintained. In general, investigations of illnesses will require on-site participation of medical personnel. The record of these investigations will be available to the union. All personnel responsible for investigation of injury and illness reports and the maintenance of injury and illness records will be instructed by NERC. Special attention should be paid to diagnosis and recording criteria for repeated trauma disorders, strains and sprains, back injuries, and traumatic events.

4(c) Accident Recordkeeping Forms The following accident reporting and recordkeeping forms have been modeled after the U.S. OSHA 300 Log records. Modifications to the Log 300 are based on local conditions and observations pertinent to Nigeria.

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You must record information about every work-related injury or illness that involves loss of consciousness, restricted work activity or job transfer, days away from work, or medical treatment beyond first aid. You must also record significant work-relate

(D) Date of injury or onset of illness (mo./day)

(E) Where the event occurred (e.g. Loading dock north end)

State

Classify the case Using these categories, check ONLY the (F) Describe most serious result for each case: injury or illness, Days parts of Remained at work Death away from body Job affected, Other transfer or recordable and (G) (H) (I) (J) object/sub

Enter the number of days the injured or ill worker was:

Check the "injury" column or choose one type of illness: (M)

Away from On job transfer or work restriction (days) (days) (K) (L)

Page totals 0 0 0 0 0 0 Be sure to transfer these totals to the Summary page before you post it.

All other illnesses

(A) (B) (C) Case No. Employee' Job Title s Name (e.g., Welder)

Describe the case

Establishment name City

Poisoning

Identify the person

Year

Respiratory Condition

Log of Work-Related Injuries and Illnesses

Attention: This form contains information relating to employee health and must be used in a manner that protects the confidentiality of employees to the extent possible while the information is being used for occupational safety and health purposes.

Skin Disorder

NERC's Accident Reporting Form

Injury

Version 1: March 2008

(1)

(2)

(3)

(4)

(5)

0

0

0

0

0

Page 1 of 1

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NERC's Form Summary of Work-Related Injuries and Illnesses

Year

All establishments must complete this Summary page, even if no injuries or illnesses occurred during the year. Remember to review the Using the Log, count the individual entries you made for each category. Establishment information Then write the totals below, making sure you've added the entries from Your establishment name Employees former employees, and their representatives have the right to review the NERC Form in its entirety.

City

Number of Cases Total number of deaths

0 (G)

Total number of cases with days away from work 0 (H)

Total number of cases with job transfer or restriction 0 (I)

Total number of other recordable cases 0 (J)

Total number of days of job transfer or restriction

Total number of days away from work

0 (K)

0 (L)

Annual average number of employees

Total hours worked by all employees last year

Injury and Illness Types

Sign here

Knowingly falsifying this document may result in a fine. 0

(2) Skin Disorder

(4) Poisoning

0

(5) All other illnesses 0

0

(3) Respiratory Condition 0

Post this Summary page from February 1 to April 30 of the year following the year covered by the form

IV-8

Brief Description of Facility __________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________

Employment information

Number of Days

Total number of… (M) (1) Injury

Street

I certify that I have examined this document and that to the best of my knowledge the entries are true, accurate, and complete.

Company executive

Title

Phone

Date

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Part IV: Recordkeeping, Training and Inspections, Accident Investigating and Reporting

Attention: This form contains information relating to employee health and must be used in a manner that protects the confidentiality of employees to the extent possible while the information is being used for occupational safety and health purposes.

NERC's Form Injuries and Illnesses Incident Report

Information about the employee This Injury and Illness Incident Repor t is one of the first forms you must fill out when a recordable workrelated injury or illness has occurred.

1)

Full Name

10) Case number from the Log

2)

Street

11) Date of injury or illness State

City

Within 7 calendar days after you receive information that a recordable work-related injury or illness has occurred, you must fill out this form or an equivalent.

Information about the case (Transfer the case number from the Log after you record the case.)

12) Time employee began work

AM/PM

AM/PM

Check if time cannot be determined

3)

Date of birth

13) Time of event

4)

Date hired

14) What was the employee doing just before the incident occurred? Describe the activity, as well as the tools, equipment or material the employee was using.

5)

Male Female Information about the physician or other health care professional

6)

If you need additional copies of this form, you may 7) photocopy and use as many as you need.

Name of physician or other health care professional

If treatment was given away from the worksite, where was it given? 16) What was the injury or illness? Tell us the part of the body that was affected and how it was affected; be more specific than "hurt", "pain", or "sore." Examples: "strained back"; "chemical burn, hand"; "carpal tunnel syndrome."

Facility Street State

City 8) Completed by

What happened? Tell us how the injury occurred. Example: "When ladder slipped on wet 15) floor, worker fell 20 feet";

Was employee treated in an emergency room? Yes

17) What object or substance directly harmed the employee? Examples: "concrete floor"; "chlorine"; "radial arm saw." If this question does not apply to the incident, leave it blank.

No Title 9) Phone

Date

Was employee hospitalized overnight as an in-patient? Yes No

18) If the employee died, when did death occur? Date of death

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4(d) Safety Training and Recordkeeping 4(d)(1) Type of Training Each organization should develop appropriate safety training programs. Programs should be tailored to the needs of the organization and based on a job hazards evaluation. At a minimum, all employees must receive hazard awareness training in addition to job specific training with emphasis on safe practices and familiarity with the NERC safety standards. The following are some recommended programs that organizations may consider developing: •

•

•

•

•

•

•

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Accident Investigation Training for Supervisors and Safety Teams (2 hours) – Defines an "accident" in the workplace and explains why they should be investigated. Covers the rules of accident investigation and how to illicit information from victims and witnesses. Training should also cover the importance of investigating "near miss" incidents. Recommended for supervisors and safety committees. Back Injury Prevention (1 1/2 hours) – This session should cover statistics and causes of back pain and injury in the workplace. It also should discuss contributing factors such as medical conditions, lifestyle, posture and body mechanics. It should emphasize employee and employer responsibilities to help prevent back injuries in the workplace. Bloodborne Pathogens Awareness Training (1 hour awareness, 2 hour in-depth) – Such a course will inform employees of the hazards due to occupational exposure to bloodborne pathogens (Contained in blood and other potentially infectious materials). Participants should be informed of the employer's Exposure Control Plan and its contents. Simple awareness training is usually adequate for non-medical personnel. Confined Space Entry Training (1 hour unless performing rescue) – The course should explain what confined spaces are and NERC's requirements for working in and around these spaces. This training can be performed according to the employer's Confined Space Entry Program and can also include a simulated rescue utilizing the employer's rescue equipment. General Safety Awareness Training (1 1/2 hours) – This session should touch on all of NERC's requirements regarding employer responsibilities for worker safety. It is recommended that the session include information on NERC's General Duty Clause, Hazard Communication, Fire Extinguishers in the Workplace, First Aid and Bloodborne Pathogens, Lock Out, Tag Out, Personal Protective Equipment, Employer Safety Programs, Confined Space Entry, Hearing Conservation Programs, Lift Truck Requirements, Respiratory Protection, NERC Citation Trends, and Common Shop Violations. Hearing Conservation Training (1 hour) – This session should cover NERC's requirements for employers who have employees exposed to noise in the workplace. It should examine time-weighted-averages and decibel level exposures. It should also cover the employers’ responsibility for having a written Hearing Conservation Program and the components required in it. It should also discuss requirements for annual audiometric testing and follow-up, training, access to information and recordkeeping for employees included in the program. Heat Stress in the Workplace (1/2 to 1 hour) – This session should cover risk factors (human and environmental) associated with heat stress injuries/illnesses. It should define signs and symptoms of heat-related illnesses including heat rash, heat cramps, heat

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syncope, heat exhaustion and heat stroke. It should also cover first aid procedures related to each as well as engineering and work practice controls to avoid heat stress. Ladder Safety (1/2 hour) – It is recommended that a basic session detailing NERC requirements for ladders and proper usage in the workplace including proper selection, inspection, set-up and use be implemented. Lock Out, Tag Out (1 hour awareness, 2 to 3 hour in-depth) – This session should inform employees of NERC’s requirements. This course should cover the proper measures for preventing the release or escape of hazardous energy (electrical, mechanical, thermal and other potential sources). Elements of this program should discuss required documented energy control procedures (written plans), employee training requirements and periodic inspections of the use of these procedures. Awareness training should be done on employees working on or around equipment that has been locked out and in-depth training should be done for those employees who actually perform the lock-out function. Office Safety (1/2 to 1 hour) – Office personnel are not immune to workplace injuries. This session should detail workplace hazards in an office setting including chairs and desks, stacking and storage, stairs, filing cabinets, office machines, slips trips and falls, proper office layout, lighting, housekeeping, ergonomics, material handling, electrical/heat-generating appliances, chemical safety and lock-out, tag-out. NERC Log Training (Recordkeeping Requirements - 2 to 3 hours) – This session should cover requirements of NERC’s Records keeping Standard (Part 4) including how to fill out the NERC Incident Reporting forms. Such a program will help those required to keep these forms to know what constitutes a NERC recordable injury and/or illness and the importance of not over or under-recording. Safety Committees (2 hours) – This program should detail how to put together an effective safety committee, how an effective committee operates and the purpose they exist. It should cover proper make-up of a committee and discuss why safety committees sometimes fail to meet their objectives. Good, practical advice on how to have a successful and productive safety committee should be offered. Safety Training for Supervisors and Managers (1 to 2 hours) – This session should approach safety in the workplace from the manager or supervisor's standpoint. This program will help those in authority prioritize safe work practices and convey the importance of safety to their employees.

The employer may find the need to develop other programs. Not all programs should be mandatory – rather those which address site-specific hazards, job functions and working conditions. In addition to the recommended programs above, facilities should consider developing written safety programs for some or all of the topics listed below and then familiarizing workers with them in safety meetings and training sessions: • • • • • •

Asbestos Safety Program Assured Equipment Grounding Program Benzene Safety Program Chemical Hygiene Plan Chemical Labeling Program Compressed Gas Safety Program

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Contractor Safety Verification Program Crane Safety Program Crisis Management Plan Drug Free Workplace Program – State and Federal Electrical Safety Hazards Program Eye/Face Protection Program Eyewash Station Program Facility Evacuation Plan Facility Smoking Program Facility Physical Security Plan Fall Protection Program Fire Extinguisher Program Fire Prevention Program First Aid Response Program Flammable and Combustible Liquids Safety Program Forklift Safety Program Hand and Power Tool Safety Program Hazard Communication Program Industrial Housekeeping Program Industrial Burn Safety Laboratory Safety Program Laser Safety Program Light Duty - Return To Work Program Loading Dock Safety Program Machine Guarding Program Marking Industrial Hazards Program Medical Services and First Aid Program MSDS Development Program New Products, Procedures, Equipment Program Overall Company Safety Program Portable Ladder Safety Program Power Press Safety Program PPE and Job Hazard Analysis Program Preparing for Workplace Emergencies Radiation Safety for X-ray Units Respiratory Protection Program Safety Committee Program Sand Abrasive Blasting Safety Program Scaffolding Safety Program Sling Safety Program Slips, Trips, & Falls Safety Program Spill Prevention, Control and Countermeasure Stairway and Ladder Safety Program Supervisor Safety Program

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Trenching and Excavations Program Violence in the Workplace Program Welding Safety Program Working in Hot Conditions Program Workplace Back Safety Bomb Threat Response Program Aerial Lift and Scissors Lift Safety Program Electrical Safety for Unqualified Employees Program.

4(d)(2) Recordkeeping Employers should maintain records of employee training for all employees for the life of employment and up to five years beyond retirement or termination. The records shall include name of employee, name of training session, dates of training, and number of contact hours. The records should be made available to NERC inspectors upon request. Maintaining accurate records will protect both employees and employers from liabilities and will help to identify areas where safer working environments can be created. It is recommended that each organization adopt the use of Continuing Education Units (CEUs) to keep track of overall training records for employees. The Continuing Education Unit (CEU) is an internationally recognized method of quantifying the time spent in the classroom during professional development and training activities. Ten hours of instruction = 1.0 CEU. One hour of instruction = 0.1 CEU. 4(e) OHSAS 18001 (Occupation Health and Safety Assessment Series) The following section is general information on the OHSAS 18000 series. OHSAS 18000 is a voluntary program which the NERC recommends organizations consider adopting to improve safety performance. OHSAS 18000 is an international occupational health and safety management system specification. It comprises two parts, 18001 and 18002, and embraces BS8800 (British Standard) and a number of other publications. OHSAS 18001 was created via a concerted effort from a number of the worlds leading national standards bodies, certification bodies, and specialist consultancies. OHSAS helps in a variety of respects. It helps: minimize risk to employees/etc; improve an existing OH&S (Occupational Health and Safety) management system; demonstrate diligence; gain assurance; etc. Central to OHSAS requirements are strong policies and procedures. Occupational Health & Safety is a subject that must be addressed by all organizations large and small. The organization's management system should identify all legislative requirements, identify the hazards and control the risks of the organization. Progressive businesses will aim to go beyond compulsory measures and promote continuous improvement on health and safety matters. IV-13

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Managing the health and safety of an organization can be approached using a structured management system and it can be integrated into current systems, to reduce the burden of bureaucracy. A formal H&S management system will provide the following benefits: • • • • • •

A system for continually identifying legal and other requirements. A clear management structure delegating authority and responsibility. A clear set of objectives for improvement, with measurable results. A structured approach to risk assessment within the organization. A planned and documented approach to health and safety. The monitoring of health and safety management issues, auditing of performance and review of policies and objectives.

Time spent on improving an organization's health and safety could provide a financial return in terms of: • • • •

Reduced accidents and occupational ill health. Reduced stress and greater productivity. An improvement in underwriting risk. A reduction in the likelihood of paying regulatory compliance fees.

For many years, there has been demand for a certification scheme for occupational health and safety, which intensified with the publication of BS 8800 in 1996. However, while BS 8800 offers guidance on implementing an occupational health & safety management system, it is not and never was intended for certification purposes. The pressure was for a certification scheme that could offer independent verification that an organization has taken all reasonable measures to minimize risks and prevent accidents. The situation prompted many certification bodies to develop their own specifications based on BS 8800. The inevitable irregularities between the specifications made this an undesirable way forward. In response, a committee was formed in November 1998 chaired by the British Standards Institution, and consisted of the major certification bodies and other national standard organizations known to be active in health and safety, with the goal of creating a single specification. This resulted in the occupational health and safety assessment series OHSAS 18001, which unified the existing schemes. Guidance to this specification can be found in OHSAS 18002. The structure of OHSAS 18001 is: • • • • •

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General requirements OH&S policy Hazard identification, risk assessment and determining controls Legal and other requirements Objectives and programs

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Resources, roles, responsibility, accountability and authority Competence, training and awareness Communication, participation and consultation Documentation Control of documents Operational control Emergency preparedness and response Performance measurement and monitoring Evaluation of compliance Incident investigation, nonconformity, corrective action and preventive action Control of records Internal audit Management review.

The certification process is similar to that of ISO 9001 or ISO 14001. Once the Certification Body receives a completed application form, a Stage One assessment is undertaken on site, to determine the state of the policy, procedures and work instructions. If the readiness is satisfactory, then a date is set for the Stage Two assessment, which will assess the level of implementation. Once satisfactory, a certificate is issued. Annual surveillance ensures continued conformance. Information on the certification process can be obtained from the Internet. There are currently no costs published for certification; however it is anticipated that initially costs are high. As in the case of ISO 14001 (Environmental Management Series) companies may initially opt to sidestep certification and formally adopt the principles of OHSAS 18001. Many companies opt to formally adopt the management system and establish their own system following the OHSAS structure. Analogously, this approach has worked well in the environmental sector as there are many more companies throughout the world that have self declared ISO 14001 programs than certified programs. 4(f) Bibliography International Standards Organization, ISO 9001. International Standards Organization, ISO 14001. U.S. Department of Labor, Occupation Health and Safety Assessment Series, OHSAS 18001. U.S. Department of Labor, Occupation Health and Safety Assessment Series, OHSAS 18002. U.S. Department of Labor, Occupational Safety and Health Administration, 300 Log records.

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PART V. RISK AND VULNERABILITY ASSESSMENTS CONTENTS 5(a) Risk Management.............................................................................................................. V-3 5(a)(1) General........................................................................................................................ V-3 5(a)(2) Steps to Risk Assessment ........................................................................................... V-3 5(a)(2)(i) Step 1: Identify the Hazards................................................................................ V-4 5(a)(2)(ii) Step 2: Decide Who Might be Harmed and How .............................................. V-4 5(a)(2)(iii) Step 3: Evaluate the Risks and Decide on Precautions..................................... V-5 5(a)(2)(iv) Step 4: Record Your Findings and Implement Them ....................................... V-6 5(a)(2)(v) Step 5: Review Your Risk Assessment and Update if Necessary...................... V-6 5(a)(2)(vi) Sensible Risk Management Tips....................................................................... V-7 5(a)(3) Safety Risk Management Committees........................................................................ V-9 5(b) Crisis Management ......................................................................................................... V-10 5(c) Vulnerability Assessments .............................................................................................. V-12 5(c)(1)Network Architecture ................................................................................................ V-14 5(c)(2) Threat Environment .................................................................................................. V-14 5(c)(3) Penetration Testing ................................................................................................... V-15 5(c)(4) Physical Security....................................................................................................... V-16 5(c)(5) Physical Asset Analysis ............................................................................................ V-17 5(c)(6) Operations Security................................................................................................... V-17 5(c)(7) Policies and Procedures ............................................................................................ V-18 5(c)(8) Impact Analysis ........................................................................................................ V-18 5(c)(9) Infrastructure Interdependencies............................................................................... V-19 5(c)(10) Risk Characterization.............................................................................................. V-19 5(c)(11) Post-Assessment ..................................................................................................... V-19

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5(a) Risk Management 5(a)(1) General What constitutes a work-related injury? Any illness or injury incurred in the course of employment. This includes industrial accidents, of course, but the injury need not result from one specific event. Repetitive stress injuries, such as back strain or carpal tunnel syndrome, are legitimate worker injuries. In order to reduce accidents it is important to both identify and prevent accidents at the start, but also to immediately report incidents and to learn from them. There are no reliable accident statistics in Nigeria, and hence other countries are used by way of examples. According to the National Council on Compensation Insurance (NCCI), the average cost per worker compensation claim in 1996 and 1997 was $10,105 (the latest data available). Motor vehicle accidents were the most costly cause of injury, with an average cost per claim of $19,764. The most costly injuries were amputation, carpal tunnel syndrome, and fractures. Men are more likely to be hurt on the job than women, filing two thirds of "lost time" claims. Men are also more susceptible to traumatic and permanent injuries. Women, by contrast, are more likely to file mental stress and cumulative-injury claims. Fueled by statistics like these, on-site safety training or safety-management sessions with managers and employees should be viewed as critical. Companies might promote this as a bonus policy feature, and if you're a small company with few safety-management resources, this can be a huge help in reducing injuries and increasing efficiency. From a practical standpoint, companies may view this as loss-control services. If you're a smaller employer, chances are you don't maintain an internal risk management department. There are, however, many independent risk managers and safety consultants who can work with you to implement safety policies — good accident-reporting practices, safety training for employees, and meeting NERC requirements for your industry can help you keep loss time down by having the right procedures (and the right safety record) in place. Safety should not be something you talk about once a month. Safety should be in everything you do. Employers need to establish a safety culture – practices and policies that can reduce workers injuries from a humanitarian and a financial standpoint. First and foremost in safety management, is a safety committee, a group of managers and workers that discuss aspects of the workplace and what can be done to improve upon safety and health conditions. The safety committee should be weighted to the side of the workers. They're involved in the dayto-day processes, and can bring ideas to the table on how to make them safer. Involving employees in that kind of forum is extremely important, because they see themselves as being involved in the process and can take that perspective back to the rest of the employees. 5(a)(2) Steps to Risk Assessment A risk assessment is an important step in protecting your workers and your business, as well as complying with the law. It helps you focus on the risks that really matter in your workplace – the

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ones with the potential to cause real harm. In many instances, straightforward measures can readily control risks, for example ensuring spillages are cleaned up promptly so people do not slip, or cupboard drawers are kept closed to ensure people do not trip. For most, that means simple, cheap and effective measures to ensure your most valuable asset - your workforce - is protected. A risk assessment is simply a careful examination of what, in your work, could cause harm to people, so that you can weigh up whether you have taken enough precautions or should do more to prevent harm. Workers and others have a right to be protected from harm caused by a failure to take reasonable control measures. Accidents and ill health can ruin lives and affect your business too if output is lost, machinery is damaged, insurance costs increase or you have to go to court. You are legally required to assess the risks in your workplace so that you put in place a plan to control the risks. To assess the risks in your workplace follow the five steps below: 1. 2. 3. 4. 5.

Identify the hazards; Decide who might be harmed and how; Evaluate the risks and decide on precaution; Record your findings and implement them; and Review your assessment and update if necessary.

5(a)(2)(i) Step 1: Identify the Hazards First you need to work out how people could be harmed. When you work in a place everyday it is easy to overlook some hazards, so here are some tips to help you identify the ones that matter: • • • • • •

Walk around your workplace and look at what could reasonably be expected to cause harm. Ask your employees or their representatives what they think. They may have noticed things that are not immediately obvious to you. If you are a member of a trade association, contact them. Many produce very helpful guidance. Check manufacturers’ instructions or data sheets for chemicals and equipment as they can be very helpful in spelling out the hazards and putting them in their true perspective. Have a look back at your accident and ill-health records – these often help to identify the less obvious hazards. Remember to think about long-term hazards to health (e.g., high levels of noise or exposure to harmful substances) as well as safety hazards.

5(a)(2)(ii) Step 2: Decide Who Might be Harmed and How For each hazard you need to be clear about who might be harmed; it will help you identify the best way of managing the risk. That doesn’t mean listing everyone by name, but rather identifying groups of people (e.g. ‘people working in the storeroom’ or ‘passers-by’).

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Remember: • • • • •

some workers have particular requirements, e.g. new and young workers, new or expectant mothers and people with disabilities may be at particular risk. Extra thought will be needed for some hazards; cleaners, visitors, contractors, maintenance workers etc, who may not be in the workplace all the time; members of the public, if they could be hurt by your activities; if you share your workplace, you will need to think about how your work affects others present, as well as how their work affects your staff – talk to them; and ask your staff if they can think of anyone you may have missed.

In each case, identify how they might be harmed, i.e. what type of injury or ill health might occur. For example, ‘shelf stackers may suffer back injury from repeated lifting of boxes.’ 5(a)(2)(iii) Step 3: Evaluate the Risks and Decide on Precautions Having spotted the hazards, you then have to decide what to do about them. The NERC standards require you to do everything ‘reasonably practicable’ to protect people from harm. You can work this out for yourself, but the easiest way is to compare what you are doing with good practice. Initially, look at what you’re already doing, think about what controls you have in place and how the work is organized. Then compare this with the good practice and see if there’s more you should be doing to bring yourself up to standard. In asking yourself this, consider: • •

Can I get rid of the hazard altogether? If not, how can I control the risks so that harm is unlikely?

When controlling risks, apply the principles below, if possible in the following order: • • • • •

try a less risky option (e.g., switch to using a less hazardous chemical); prevent access to the hazard (e.g., by guarding); organize work to reduce exposure to the hazard (e.g., put barriers between pedestrians and traffic); issue personal protective equipment (e.g., clothing, footwear, goggles etc); and then provide welfare facilities (e.g., first aid and washing facilities for removal of contamination).

Improving health and safety need not cost a lot. For instance, placing a mirror on a dangerous blind corner to help prevent vehicular accidents is a low-cost precaution considering the risks. Failure to take simple precautions can cost you a lot more if an accident does happen. Involve staff, so that you can be sure that what you propose to do will work in practice and won’t introduce any new hazards.

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5(a)(2)(iv) Step 4: Record Your Findings and Implement Them Putting the results of your risk assessment into practice will make a difference when looking after people and your business. Writing down the results of your risk assessment, and sharing them with your staff, encourages you to do this. If you have fewer than five employees you do not have to write anything down, though it is useful so that you can review it at a later date if, for example, something changes. When writing down your results, keep it simple, for example ‘Tripping over rubbish: bins provided, staff instructed, weekly housekeeping checks’, or ‘Fume from welding: local exhaust ventilation used and regularly checked.’ We do not expect a risk assessment to be perfect – but it must be suitable and sufficient. You need to be able to show that: • • • • •

A proper check was made; You asked who might be affected; You dealt with all the obvious significant hazards, taking into account the number of people who could be involved; The precautions are reasonable, and the remaining risk is low; and You involved your staff or their representatives in the process.

If, like many businesses, you find that there are quite a lot of improvements that you could make, big and small, don’t try to do everything at once. Make a plan of action to deal with the most important things first. Health and safety inspectors acknowledge the efforts of businesses that are clearly trying to make improvements. A good plan of action often includes a mixture of different things such as: • • • • • •

a few cheap or easy improvements that can be done quickly, perhaps as a temporary solution until more reliable controls are in place; long-term solutions to those risks most likely to cause accidents or ill health; long-term solutions to those risks with the worst potential consequences; arrangements for training employees on the main risks that remain and how they are to be controlled; regular checks to make sure that the control measures stay in place; and clear responsibilities – who will lead on what action, and by when.

Remember, prioritize and tackle the most important things first. As you complete each action, tick it off your plan. 5(a)(2)(v) Step 5: Review Your Risk Assessment and Update if Necessary Few workplaces stay the same. Sooner or later, you will bring in new equipment, substances and procedures that could lead to new hazards. It makes sense therefore, to review what you are

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doing on an ongoing basis. Every year or so, formally review where you are to make sure you are still improving, or at least not sliding back. Look at your risk assessment again. Have there been any changes? Are there improvements you still need to make? Have your workers spotted a problem? Have you learned anything from accidents or near misses? Make sure your risk assessment stays up to date. When you are running a business, it’s all too easy to forget about reviewing your risk assessment – until something has gone wrong and it’s too late. Why not set a review date for this risk assessment now? Write it down and note it in your diary as an annual event. During the year, if there is a significant change, don’t wait: check your risk assessment and where necessary, amend it. If possible, it is best to think about the risk assessment when you’re planning your change – that way you give yourself more flexibility. 5(a)(2)(vi) Sensible Risk Management Tips Risk management should be about practical steps to protect people from real harm and suffering – not bureaucratic back covering. If you believe some of the stories you hear, health and safety is all about stopping any activity that might possibly lead to harm. This is not the proper vision of sensible health and safety – rather the focus should be on saving lives, not stopping them. Organizations must seek a balance between the unachievable aim of absolute safety and the kind of poor management of risk that damages lives and the economy. Don’t overcomplicate the process. In many organizations, the risks are well known and the necessary control measures are easy to apply. You probably already know whether, for example, you have employees who move heavy loads and could harm their backs, or where people are most likely to slip or trip. If so, check that you have taken reasonable precautions to avoid injury. If you run a small organization and you are confident you understand what’s involved, you can do the assessment yourself. You don’t have to be a health and safety expert. If you work in a larger organization, you could ask a health and safety advisor to help you. If you are not confident, get help from someone who is competent. In all cases, you should make sure that you involve your staff or their representatives in the process. They will have useful information about how the work is done that will make your assessment of the risk more thorough and effective. But remember, you are responsible for seeing that the assessment is carried out properly. When thinking about your risk assessment, remember: • •

a hazard is anything that may cause harm, such as chemicals, electricity, working from ladders, an open drawer etc; and the risk is the chance, high or low, that somebody could be harmed by these and other hazards, together with an indication of how serious the harm could be.

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Some frequently asked questions: 1. What if the work I do varies a lot, or I (or my employees) move from one site to another? a. Identify the hazards you can reasonably expect and assess the risks from them. This general assessment should stand you in good stead for the majority of your work. Where you do take on work or a new site that is different, cover any new or different hazards with a specific assessment. You do not have to start from scratch each time. 2. What if I share a workplace? a. Tell the other employers and self-employed people there about any risks your work could cause them, and what precautions you are taking. Also, think about the risks to your own workforce from those who share your workplace. 3. Do my employees have responsibilities? a. Yes. Employees have legal responsibilities to co-operate with their employer’s efforts to improve health and safety (eg they must wear protective equipment when it is provided), and to look out for each other. 4. What if one of my employee’s circumstances change? a. You’ll need to look again at the risk assessment. You are required to carry out a specific risk assessment for new or expectant mothers, as some tasks (heavy lifting or work with chemicals for example) may not be appropriate. If an employee develops a disability then you are required to make reasonable adjustments. People returning to work following major surgery may also have particular requirements. If you put your mind to it, you can almost always find a way forward that works for you and your employees. 5. What if I have already assessed some of the risks? a. If, for example, you use hazardous chemicals and you have already assessed the risks to health and the precautions you can consider them ‘checked’ and move on. Safety risk assessments, to the maximum extent feasible: 1. 2. 3. 4. 5. 6. 7. 8.

Are scientifically objective. Are unbiased. Include all relevant data available. Employ default or conservative assumptions only if situation-specific information is not reasonably available. The basis of these assumptions must be clearly identified. Distinguish clearly as to what risks would be affected by the decision and what risks would not. Are reasonably detailed and accurate. Relate to current risk or the risk resulting from not adopting the proposal being considered. Allow for unknown and/or unquantifiable risks.

The principles to be applied when preparing safety risk assessments are: 1. Each risk assessment should first analyze the two elements of risk: severity of the hazard and likelihood of occurrence. Risk assessment is then performed by comparing the combined effect of their characteristics to acceptable criteria as determined in the plan.

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2. A risk assessment may be qualitative and/or quantitative. To the maximum extent practicable, these risk assessments will be quantitative. 3. The selection of a risk assessment methodology should be flexible. 4. Basic assumptions should be documented or, if only bounds can be estimated reliably, the range encompassed should be described. 5. Significant risk assessment assumptions, inferences, or models should: a. Describe any model used in the risk assessment and make explicit the assumptions incorporated in the model. b. Identify any policy or value judgments. c. Explain the basis for choices. d. Indicate the extent that the model and the assumptions incorporated have been validated by or conflict with empirical data. 6. All safety risk assessments should include or summarize the information gathered. This record should be maintained by the organization performing the assessment. 5(a)(3) Safety Risk Management Committees A safety risk management committee can provide a valuable service to the organization for safety risk management planning. It can meet periodically to exchange risk management ideas and information. The committee can provide advice and counsel to the managers when requested. The Safety Risk Management Committee provides a communication and support team to supplement the overall risk analysis capability and efficiency of key managers. The Committee supports safety risk management activities. It provides advice and guidance, upon request from responsible program offices, to help them fulfill their authority and responsibility to incorporate safety risk management as a decision-making tool. It serves as an internal vehicle for risk management process communication, for coordination of risk analysis methods, and for use of common practices where appropriate. This includes, but is not limited to: 1. Continuing the internal exchange of risk management information. 2. Fostering the exchange of risk management ideas and information to avoid duplication of effort. 3. Providing risk analysis/management advice and guidance. 4. Identifying and recommending needed enhancements to risk analysis/management capabilities and/or efficiencies upon request. 5. Maintaining a risk management resources directory that includes: a. Risk methodologies productively employed, b. Specific internal risk analysis/management expertise by methodology or tool and organizational contact point(s), and c. A central contact point for resource identification assistance. 6. Encouraging the establishment of a directory of safety information resources via the Internet. 7. Assisting in the identification of suitable risk analysis tools and initiate appropriate training in the use of these tools.

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5(b) Crisis Management Crisis prevention is very important for small public entities, companies and nonprofit organizations. Small organizations often have fewer resources to draw on when a crisis erupts, and insurance and other risk financing tools may not be an available due to the organization's meager financial resources. But every organization, from the smallest to the largest can and should take steps to prevent the preventable and prepare for the unavoidable. The key is to select the strategies that appeal to your organization and best suit your situation. Once you've undertaken some activities, your organization will be that much more fortified to withstand a crisis. Crisis management requires your investment of time and common sense, rather than a large budget. You do what you can, as you can, keeping the final goal of preserving your vital mission at the forefront. Consider your organization as a physician considers a patient. Check your nonprofit's vital signs — the ones that enable your organization to fulfill its mission by meeting critical community and citizen/customer/client needs — to establish a baseline for future diagnosis. When you detect an aberration, determine the source, identify treatment methods, apply the methods and evaluate the results. Regular checkups should be scheduled to monitor the organization's vital signs (e.g., funding stream, cash flow, employee and volunteer turnover rates, past incidents, and losses and lawsuits). This process will make a critical difference in your organization's future health. If your organization is healthy, determine what you can do to keep it that way for a long term. However, if you find weaknesses, you'll need to assess the symptoms, make a diagnosis and begin a treatment plan to cure its ailments so that it can thrive or, at the very least, ease the symptoms to enable it to survive. Weaknesses might exist in financial management, human resources, fund raising or volunteer management. The symptoms could manifest as uneven cash flow; a sharp increase in formal grievances; a complaint from a major constituency, investor or donor; or a steep reduction in volunteer hours. The financial treatment plan could involve purposefully delaying the launch of a new program to coincide with your funding cycle or applying for a line of credit. The human resources treatment plan might be to revise the staff handbook and re-train supervisors on your agency's policies and procedures. The volunteer management plan might involve identifying ways to involve volunteers more deeply in projects that are vital to the realization of your mission, or providing a wider range of opportunities for your volunteer work force. If possible, you'll want to make gradual changes, starting with the ones that will bring your organization the most benefits. You don't want the treatment to cause more damage than the disease. Instead of forcing a mountain of new policies and procedures on a staff accustomed to an informal work environment, which could send key staff running for the want ads, begin by looking at what works and what's missing. As a leader who wants a healthier entity, company or nonprofit, visualize what the organization would look like if it were strong and fortified to survive crises. Then divide and conquer the tasks required to reach your goal. How much less stressful this will be on you and your staff — and more do-able than thinking: OK, today I'm writing a crisis management plan and putting safety initiatives into practice and — and — and — or the place will fall apart tomorrow. The

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critical difference between success and failure is how you approach crisis management. Ease into making your organization healthier and more likely to avoid a preventable crisis and survive the one fated to occur, or you and your staff risk burnout without completing the job. Another strategy for getting "buy-in" from personnel is to involve a diverse group of people in your crisis planning activities. If there are nay-sayers in your agency, why not get them involved in the process of identifying the crisis risks you want to focus on and determining the strategies you'll use to address these risks? If they are part of the problem-solving process, you can turn them into ambassadors for the strategies developed by the group, even when these strategies include new policies and procedures. First, create a comprehensive directory of the organization's staff, board and key volunteers. Include home addresses, phone/fax/wireless/beeper numbers, as well as emergency contact information. Distribute the list to employees and keep copies off site, as well as in your offices. Update and redistribute the directory annually (perhaps the first business day in January or the first day of your fiscal year) or more often if you have a high turnover rate. Next, maintain a backup of your computer file server, key databases, and financial files. Update the backup weekly (at least) and store a copy off site or on site in a fireproof safe. Then, conduct an inventory of your nonprofit's assets. Include equipment, furniture, databases, records and anything else you need to fulfill your mission. Your inventory should include brand names, model numbers, location, purchase price and other key details necessary for insurance claims and replacement. Store a copy of the inventory on site (preferably in a fireproof safe) and off site. Finally, identify an attorney licensed in your state who you can call upon from time to time for advice and assistance. (If your nonprofit can't afford to pay a monthly retainer or an hourly rate, consider soliciting bids from prominent law firms, emphasizing the charitable work of your agency. Don't be surprised if you receive proposals offering pro bono or dramatically discounted legal services). For many small organizations it makes sense to convene one group to develop a crisis management plan for the organization and a second group that will serve as the nonprofit's "crisis response team." The crisis-planning group should be diverse and include people in the organization who fully understand the risks your operation faces. For example, if you own a building, including the person responsible for maintenance on your crisis planning team can help ensure that building-related hazards that could cause a crisis will be identified and addressed. Including the director of volunteers might enable the team to spot a volunteer-related hazard looming on the horizon. A crisis response team is the group of people who coordinate your nonprofit's reaction and response to a crisis. The composition of an organization's crisis response team will vary based on a wide range of factors, including: the size of the organization, the nature of the products or services provided, the likely sources of crisis in the organization, and the organization's prior experience responding to a crisis. For example, in an organization with more than 50 staff, the

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crisis response team may include a handful of key department heads plus the CEO. In an organization with fewer than 10 paid staff, the crisis response team may include one or more board members, a couple of staff and outside professional advisors. The composition of a crisis response team will vary with respect to the products and services that you offer. A team at an environmental advocacy group will differ from the team that responds to a crisis at a daycare center. In the former, the team may include an experienced lobbyist and an environmental scientist. In the latter, the team may include the organization's retained counsel, an expert on child-abuse prevention or playground safety, and parents of enrolled children. The likely sources/causes of crisis in the organization should also be considered in forming a crisis response team. Is the organization more likely to face a crisis stemming from allegations of client/staff mistreatment or a crisis caused by inadequate financial resources? The ranking of crisis risks will suggest areas of expertise and training that may be required during a crisis and individuals with special talents or expertise may be identified as necessary members of the crisis response team. If your public entity, company or nonprofit has successfully weathered a crisis in the past, you'll want to include the people who were effective in addressing that situation on your crisis response team. 5(c) Vulnerability Assessments A vulnerability assessment is the process of identifying, quantifying, and prioritizing (or ranking) the vulnerabilities in a system or organization. Examples of systems for which vulnerability assessments are performed include, but are not limited to, nuclear power plants, hydroelectric power plants, information technology systems, energy supply systems, water supply systems, transportation systems, and communication systems. Vulnerability assessments can be conducted for small businesses to large regional infrastructures. A vulnerability assessment has many things in common with a risk assessment. Assessments are typically performed according to the following steps: 1. 2. 3. 4.

Cataloging assets and capabilities (resources) in a system. Assigning quantifiable value (or at least rank order) and importance to those resources. Identifying the vulnerabilities or potential threats to each resource. Mitigating or eliminating the most serious vulnerabilities for the most valuable resources.

Classical risk analysis is principally concerned with investigating the risks surrounding physical plant (or some other object), its design, and operations. Such analyses tend to focus on causes and the direct consequences for the studied object. Vulnerability analyses, in contrast, focuses both on consequences for the object itself and on primary and secondary consequences for the surrounding environment. It also concerns itself with the possibilities of reducing such consequences and of improving the capacity to manage future incidents. In general, a vulnerability analysis serves to categorize key assets and drive the risk management process. Energy utilities should routinely perform vulnerability assessments to better understand threats and vulnerabilities, determine acceptable levels of risk, and stimulate action to mitigate identified

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vulnerabilities. According to the U.S. Department of Energy, the direct benefits of performing a vulnerability assessment include: •

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Build and broaden awareness. The assessment process directs senior management’s attention to security. Security issues, risks, vulnerabilities, mitigation options, and best practices are brought to the surface. Awareness is one of the least expensive and most effective methods for improving the organization’s overall security posture. Establish or evaluate against a baseline. If a baseline has been previously established, an assessment is an opportunity for a checkup to gauge the improvement or deterioration of an organization’s security posture. If no previous baseline has been performed (or the work was not uniform or comprehensive), an assessment is an opportunity to integrate and unify previous efforts, define common metrics, and establish a definitive baseline. The baseline also can be compared against best practices to provide perspective on an organization’s security posture. Identify vulnerabilities and develop responses. Generating lists of vulnerabilities and potential responses is usually a core activity and outcome of an assessment. Sometimes, due to budget, time, complexity, and risk considerations, the response selected for many of the vulnerabilities may be non-action, but after completing the assessment process, these decisions will be conscious ones, with a documented decision process and item-byitem rationale available for revisiting issues at scheduled intervals. This information can help drive or motivate the development of a risk management process. Categorize key assets and drive the risk management process. An assessment can be a vehicle for reaching corporate-wide consensus on a hierarchy of key assets. This ranking, combined with threat, vulnerability, and risk analysis, is at the heart of any risk management process. For many organizations, the Y2K threat was the first time a company-wide inventory and ranking of key assets was attempted. An assessment allows an organization to revisit that list from a broader and more comprehensive perspective. Develop and build internal skills and expertise. A security assessment, when not implemented in an “audit” mode, can serve as an excellent opportunity to build security skills and expertise within an organization. A well-structured assessment can have elements that serve as a forum for cross-cutting groups to come together and share issues, experiences, and expertise. External assessors can be instructed to emphasize “teaching and collaborating” rather than “evaluating” (the traditional role). Whatever an organization’s current level of sophistication, a long-term goal should be to move that organization towards a capability for self-assessment. Promote action. Although disparate security efforts may be underway in an organization, an assessment can crystallize and focus management attention and resources on solving specific and systemic security problems. Often, the people in the trenches are well aware of security issues (and even potential solutions) but are unable to convert their awareness to action. An assessment provides an outlet for their concerns and the potential to surface these issues at appropriate levels (legal, financial, executive) and achieve action. A well-designed and executed assessment not only identifies vulnerabilities and makes recommendations, it also gains executive buy-in, identifies key players, and establishes a set of cross-cutting groups that can convert those recommendations into action.

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Kick off an ongoing security effort. An assessment can be used as a catalyst to involve people throughout the organization in security issues, build cross-cutting teams, establish permanent forums and councils, and harness the momentum generated by the assessment to build an ongoing institutional security effort. The assessment can lead to the creation of either an actual or a virtual (matrixed) security organization.

The assessment methodology consists of 10 elements: 1. Network architecture; 2. Threat environment; 3. Penetration testing; 4. Physical security; 5. Physical asset analysis; 6. Operations security; 7. Policies and procedures; 8. Impact analysis; 9. Infrastructure interdependencies; and 10. Risk characterization. 5(c)(1)Network Architecture This element provides an analysis of the information assurance features of the information network(s) associated with the organization’s critical information systems. Information examined should include network topology and connectivity (including subnets), principal information assets, interface and communication protocols, function and linkage of major software and hardware components (especially those associated with information security such as intrusion detectors), and policies and procedures that govern security features of the network. Procedures for information assurance in the system, including authentication of access and management of access authorization, should be reviewed. The assessment should identify any obvious concerns related to architectural vulnerabilities, as well as operating procedures. Existing security plans should be evaluated, and the results of any prior testing should be analyzed. Results from the network architecture assessment should include potential recommendations for changes in the information architecture, functional areas and categories where testing is needed, and suggestions regarding system design that would enable more effective information and information system protection. Three techniques are used in conducting the network architecture assessment: 1. Analysis of network and system documentation during and after the site visit; 2. Interviews with facility staff, managers, and Chief Information Officer; and 3. Tours and physical inspections of key facilities. 5(c)(2) Threat Environment Development of a clear understanding of the threat environment is a fundamental element of risk management. When combined with an appreciation of the value of the information assets and systems, and the impact of unauthorized access and subsequent malicious activity, an V-14

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understanding of threats provides a basis for better defining the level of investment needed to prevent such access. The threat of a terrorist attack to the electric power infrastructure is real and could come from several areas, including physical, cyber, and interdependency. In addition, threats could come from individuals or organizations motivated by financial gain or persons who derive pleasure from such penetration (e.g., recreational hackers, disgruntled employees). Other possible sources of threats are those who want to accomplish extremist goals (e.g., environmental terrorists, antinuclear advocates) or embarrass one or more organizations. This element should include a characterization of these and other threats, identification of trends in these threats, and ways in which vulnerabilities are exploited. To the extent possible, characterization of the threat environment should be localized, that is, within the organization’s service area. 5(c)(3) Penetration Testing The purpose of network penetration testing is to utilize active scanning and penetration tools to identify vulnerabilities that a determined adversary could easily exploit. Penetration testing can be customized to meet the specific needs and concerns of the utility. In general, penetration testing should include a test plan and details on the rules of engagement (ROE). It should also include a general characterization of the access points to the critical information systems and communication interface connections, modem network connections, access points to principal network routers, and other external connections. Finally, penetration testing should include identified vulnerabilities and, in particular, whether access could be gained to the control network or specific subsystems or devices that have a critical role in assuring continuity of service. Penetration testing consists of an overall process for establishing the ground rules or ROE for the test; establishing a white cell for continuous communication; developing a format or methodology for the test; conducting the test; and generating a final report that details methods, findings, and recommendations. Penetration testing methodology consists of three phases: reconnaissance, scenario development, and exploitation. A one-time penetration test can provide the utility with valuable feedback; however, it is far more effective if performed on a regular basis. Repeated testing is recommended because new threats develop continuously, and the networks, computers, and architecture of the utility are likely to change over time.

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5(c)(4) Physical Security The purpose of a physical security assessment is to examine and evaluate the systems in place (or being planned) and to identify potential improvements in this area for the sites evaluated. Physical security systems include access controls, barriers, locks and keys, badges and passes, intrusion detection devices and associated alarm reporting and display, closed-circuit television (assessment and surveillance), communications equipment (telephone, two-way radio, intercom, cellular), lighting (interior and exterior), power sources (line, battery, generator), inventory control, postings (signs), security system wiring, and protective force. Physical security systems are reviewed for design, installation, operation, maintenance, and testing. The physical security assessment should focus on those sites directly related to the critical facilities, including information systems and assets required for operation. Typically included are facilities that house critical equipment or information assets or networks dedicated to the operation of electric or gas transmission, storage, or delivery systems. Other facilities can be included on the basis of criteria specified by the organization being assessed. Appropriate levels of physical security are contingent upon the value of company assets, the potential threats to these assets, and the cost associated with protecting the assets. Once the cost of implementing/maintaining physical security programs is known, it can be compared to the value of the company assets, thus providing the necessary information for risk management decisions. The focus of the physical security assessment task is determined by prioritizing the company assets; that is, the most critical assets receive the majority of the assessment activity At the start of the assessment, survey personnel should develop a prioritized listing of company assets. This list should be discussed with company personnel to identify areas of security strengths and weaknesses. During these initial interviews, assessment areas that would provide the most benefit to the company should be identified; once known, they should become the major focus of the assessment activities. The physical security assessment of each focus area usually consists of the following: • • • • • • • •

Physical security program (general); Physical security program (planning); Barriers; Access controls/badges; Locks/keys; Intrusion detection systems; Communications equipment; and Protective force/local law enforcement agency.

The key to reviewing the above topics is not to just identify if they exist, but to determine the appropriate level that is necessary and consistent with the value of the asset being protected. The physical security assessment worksheets provide guidance on appropriate levels of protection. Once the focus and content of the assessment task have been identified, the approach to conducting the assessment can be either at the “implementation level” or at the “organizational V-16

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level.” The approach taken depends on the maturity of the security program. For example, a company with a solid security infrastructure (staffing, plans/procedures, funding) should receive a cursory review of these items. However, facilities where the security programs are being implemented should receive a detailed review. The security staff can act upon deficiencies found at the facilities, once reported. For companies with an insufficient security organization, the majority of time spent on the assessment should take place at the organizational level to identify the appropriate staffing / funding necessary to implement security programs to protect company assets. Research into specific facility deficiencies should be limited to finding just enough examples to support any staffing / funding recommendations. 5(c)(5) Physical Asset Analysis The purpose of the physical asset analysis is to examine the systems and physical operational assets to ascertain whether vulnerabilities exist. Included in this element is an examination of asset utilization, system redundancies, and emergency operating procedures. Consideration should also be given to the topology and operating practices for electric and gas transmission, processing, storage, and delivery, looking specifically for those elements that either singly or in concert with other factors provide a high potential for disrupting service. This portion of the assessment determines company and industry trends regarding these physical assets. Historic trends, such as asset utilization, maintenance, new infrastructure investments, spare parts, SCADA linkages, and field personnel are part of the scoping element. Key output from analysis should be graphs that show trends. The historic data analysis should be supplemented with on-site interviews and visits. Items to focus on during a site visit include the following: • • • • • • • • • • •

Trends in maintenance expenditures and field staffing; Trends in infrastructure investments; Historic infrastructure outages; Critical system components and potential system bottlenecks; Overall system operation controls; Use and dependency of SCADA systems; Linkages of operation staff with physical and IT security; Adequate policies and procedures; Communications with other regional utilities; Communications with external infrastructure providers; and Adequate organizational structure.

5(c)(6) Operations Security Operations security (OPSEC) is the systematic process of denying potential adversaries (including competitors or their agents) information about capabilities and intentions of the host organization. OPSEC involves identifying, controlling, and protecting generally non-sensitive activities concerning planning and execution of sensitive activities. The OPSEC assessment reviews the processes and practices employed for denying adversary access to sensitive and non-

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sensitive information that might inappropriately aid or abet an individual’s or organization’s disproportionate influence over system operation (e.g., electric markets, grid operations). This assessment should include a review of security training and awareness programs, discussions with key staff, and tours of appropriate principal facilities. Information that might be available through public access should also be reviewed. 5(c)(7) Policies and Procedures The policies and procedures by which security is administered: (1) provide the basis for identifying and resolving issues; (2) establish the standards of reference for policy implementation; and (3) define and communicate roles, responsibilities, authorities, and accountabilities for all individuals and organizations that interface with critical systems. They are the backbone for decisions and day-to-day security operations. Security policies and procedures become particularly important at times when multiple parties must interact to effect a desired level of security and when substantial legal ramifications could result from policy violations. Policies and procedures should be reviewed to determine whether they (1) address the key factors affecting security; (2) enable effective compliance, implementation, and enforcement; (3) reference or conform to established standards; (4) provide clear and comprehensive guidance; and (5) effectively address the risks. The objective of the policies and procedures assessment task is to develop a comprehensive understanding of how a facility protects its critical assets through the development and implementation of policies and procedures. Understanding and assessing this area provide a means of identifying strengths and areas for improvements that can be achieved through: • • • • •

Modification of current policies and procedures; Implementation of current policies and procedures; Development and implementation of new policies and procedures; Assurance of compliance with policies and procedures; and Cancellation of policies and procedures that are no longer relevant, or are inappropriate, for the facility’s current strategy and operations

5(c)(8) Impact Analysis A detailed analysis should be conducted to determine the influence that exploitation of unauthorized access to critical facilities or information systems might have on an organization’s operations (e.g., market and/or physical operations). In general, such an analysis would require thorough understanding of: (1) the applications and their information processing; (2) decisions influenced by this information; (3) independent checks and balances that might exist regarding information upon which decisions are made; (4) factors that might mitigate the impact of unauthorized access; and (5) secondary impacts of such access (e.g., potential destabilization of organizations serving the grid, particularly those affecting reliability or safety). Similarly, the physical chain of events following disruption, including the primary, secondary, and tertiary impacts of disruption, should be examined. The purpose of the impact analysis is to help estimate the impact that outages could have on a utility. Outages in electric power, natural gas, and oil can have significant financial and external

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consequences to a utility. The impact analysis provides an introduction to risk characterization by providing quantitative estimates of these impacts so that the utility can implement a risk management program and weigh the risks and costs of various mitigation measures. 5(c)(9) Infrastructure Interdependencies The term “infrastructure interdependencies” refers to the physical and electronic (cyber) linkages within and among our nation’s critical infrastructures — energy (electric power, oil, natural gas), telecommunications, transportation, water supply systems, banking and finance, emergency services, and government services. This task identifies the direct infrastructure linkages between and among the infrastructures that support critical facilities as recognized by the organization. Performance of this task requires a detailed understanding of an organization’s functions, internal infrastructures, and how these link to external infrastructures. The purpose of the infrastructure interdependencies assessment is to examine and evaluate the infrastructures (internal and external) that support critical facility functions, along with their associated interdependencies and vulnerabilities. 5(c)(10) Risk Characterization Risk characterization provides a framework for prioritizing recommendations across all task areas. The recommendations for each task area are judged against a set of criteria to help prioritize the recommendations and assist the organization in determining the appropriate course of action. It provides a framework for assessing vulnerabilities, threats, and potential impacts (determined in the other tasks). In addition, the existing risk analysis and management process at the organization should be reviewed and, if appropriate, utilized for prioritizing recommendations. The degree to which corporate risk management includes security factors is also evaluated. 5(c)(11) Post-Assessment The post-assessment phase involves prioritizing assessment recommendations, developing an action plan, capturing lessons learned and best practices, and conducting training. The risk characterization element results provide the basis for the post-assessment by providing prioritized lists of recommendations that are ranked by key criteria. The company should take the prioritized lists and validate the recommendations and costs. Recommendations that are low cost or result in cost savings should be singled out for special attention. Other recommendations, however, might require formidable financial resources for implementation and require knowledge of the current company financial situation and posture toward risk. Each company should carefully evaluate the costs and benefits of each recommendation. Recommendations compared in this section include making trade-offs in improvements in each of the other element areas. For example, which physical security measures should be selected versus changes in policies and procedures and network architecture? These are difficult decisions to make and a risk management framework combined with a diverse group of company decision makers should be a part of this decision making process.

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The next step is to develop an action plan that includes timelines, staffing assignments, and budgets to implement the proposed recommendations. Lessons learned should be captured along the way to improve the overall process in the future. Training and other technical support activities, such as workshops, are also appropriate throughout the process.

This Section is reserved for further expansion by NERC as standards are updated in the future and resources expanded on Vulnerability Assessments.

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