Isc Tanker Safety Guide Chemical.pdf

TANKER SAFETY GUIDE CHEMICALS FOURTH EDITION

INTERNATIONAL CHAMBER OF SHIPPING

INTERNATIONAL CHAMBER OF SHIPPING Established in 1921, the International Chamber of Shipping (ICS) is the principal international trade association for shipowners, representing the global industry at IMO and the other international bodies that impact o n shipping. Its membership comprises national shipowners' associations from 36 countries, covering all sectors and trades and over 80% of the world merchant fleet.

Wh ile the advice given in this Guide has been developed using the best information available, it is to be followed at the users' own risk. No responsibility is accepted by Maritime International Secretariat Services Limited, or by the International Chamber of Shipping Limited, or by any firm, corporation or organisation who or which has been in any way concerned with the furnishing of data, the compilation, publication or authorised translation, supply or sale of this guidance, for the accuracy of any information or advice given herein, or any omission herefrom or consequences whatsoever resulting directly or indirectly from use of this Guide, or from compliance with or adoption of guidance contained herein, even if caused by a failure to exercise reasonable Cilre.

INTERNATIONAL CHAMBER OF SHIPPING

TANKER SAFETY GUIDE (CHEMICALS) FOURTH EDITION Published by Maritime International Secretariat Services Limited 38 St Mary Axe, London, EC3A 8BH Tel Email Web

+44 20 7090 1460 [email protected] www.ics-shipping.org

© Maritime International Secretariat Services Limited 2014 No translation of this guide into a foreign language may be made without the express permission of Maritime International Secretariat Services Limited.

2

TANKER SAFETY GUIDE (CHEMICALS)

FOREWORD TO THE FOURTH EDITION The first edition of the ICS Tanker Safety Guide (Chemicals) was published in 1971 and complemented the first International Maritime Organization (IMO) Code for the Construction and Equipment of Ships Carrying Dangerous Chemicals in Bulk. The ICS Guide was developed from a clear demand, from shipping companies and seafarers, for advice on best practice with respect to safety at sea. The ICS Guide has si nce become the standard reference work on chemical tanker operations, with subsequent editions taking particular account of the need for chemical tankers to comply with additional IMO regulations to ensure the prevention of pollution. It is recommended that a copy should be carried on board every tanker engaged in the carriage of chemicals by sea. This fourth edition of the Guide is the result of substantial revision and updating. In response to feedback from users, and i n order to improve access to important information, much of the content from the previous edition's appendices has been incorporated i nto the mai n body of the text, while being completely redrafted in the interests of improved understanding. The latest Guide reflects the continui ng need for guidance on well established i ndustry best practice, but also takes account of more recent developments which have emerged in the chemical trades. In particular, it should be noted that this updated edition addresses IMO's adoption, in May 2014, of important new SOLAS requirements for the fitting and use of inert gas on board ch emical tankers. This followed an in depth IMO review of tanker safety- in which ICS participated - that has taken th e best part of a decade. Earlier editions of this ICS Guide provided advice on the precautions to be taken prior to entering enclosed spaces and cargo tanks. In the i nterveni ng years, serious enclosed space accidents have unfortunately continued to occur, primarily due to a failure to follow establish ed procedures. The need for updated and improved guidance on this most important safety topic has therefore been given even greater emphasis, with separate chapters dedicated to both enclosed space entry precautions and to the correct use of nitrogen as an inerting medium. A new feature introduced in this edition is the use of yellow coloured text boxes. These contain a summary of information of adjacent text regarding a particular safety issue. Although readers should pay particular attention to the advice provided in th ese yellow boxes, it should be understood that these only serve to amplify the main text, and that a full and careful reading of all advice relating to a particular subject is essential in order to achieve a comprehensive understanding. Following the example of the previous edition, a model Material Safety Data Sheet (MSDS) has been i ncluded to encourage the presentation of data in a standard format. This is particularly important w ith regard to emergency and first aid information, which needs to be readily identifiable and in a common layout. When a ship is at sea, or at a remote terminal, external assistance may not be available, and easily accessible emergency advice is therefore vital. Emphasis also continues to be given to the importance of ships and terminals completing the Ship/Shore Safety Checklist in advance of conducting any cargo operations in port, with a revised Checklist and full guidance for completion being incorporated as Appendices. Last but not least, particular attention has been given to th e best means of instilling an effective safety culture throughout ch emical tanker operations, in which everyone involved thinks of 'safety first' and f ully understands that virtually every unsafe action is preventable. No Guide of this nature can ever be complete, however much care and effort has gone into its preparation. Comments and suggestions for improvements to the Guide are therefore always welcome, and should be addressed to: International Chamber of Shippi ng 38 St Mary Axe London EC3A 8BH E-mail: info@ics-shippi ng.org

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PURPOSE AND SCOPE The purpose of this ICS Guide is to provide those serving on ships carrying hazardous and noxious chemicals i n bulk with up to date information on recognised good practice i n safe and pollution free operations. This Guide is i ntended for use on ships regulated under MARPOL Annex II (Regulations for the Prevention of Pollution by Noxious Liquid Substances) i ncluding oil tankers operating in accordance with Annex II when they are carrying chemical cargoes. However, its contents are also relevant inter alia to shipping company managers, cargo i nterests, training i nstitutes and terminal operators. The Guide is intended to be compatible with the International Safety Guide for Oil Tankers and Terminals (ISGOTI) in order to provide consistent safe advice and also to minimise the increasing burden associated with audits and vetti ng inspections. This Guide is also a companion to the ICS Tanker Safety Guide (Liquefied Gas). The Guide's recommendations cannot cover every possible situation that may be encountered on a chemical tanker, but they do provide wide general guidance on safe procedures and safe worki ng practices when handling and transporting chemicals in bulk. In the interests of consistent and uniform safe working practices, it is recommended that a copy of this Guide be kept - and used - on board all chemical tankers. Chemical tankers should also have on board ISGOTI, which should be consulted in conjunction with this Guide, especially whenever oil cargoes are carried. The Guide deals primarily with operational matters and good safety practices. It does not make recommendations on the construction or maintenance of chemical carriers or their equipment: such standards are set by IMO, national administrations and classification societies. Likewise, the Guide does not address the operation of specific items of equipment or their repair. In some cases, however, general reference is made to these matters as well as to relevant regulations. It should be noted that this Guide is not i ntended to address commercial matters such as tank cleani ng standards, cargo quality maintenance or equipment performance, which (consistent w ith IMO regulations) may be determined by industrial practices and the requirements of cargo owners.

CONTENTS OF CD ACCOMPANYING THIS GUIDE The CO accompanying this fourth edition contains the full text of the Guide with a 'search function'. The CO also contains printable/amendable versions of most appendices.

IMPORTANT NOTE

It is emphasised that this Guide is intended to complement, not supersede, any company safety and operational guidelines or ship emergency plans, including safety management procedures required by the IMO International Safety Management (ISM) Code. It should also be borne in mind that in all cases the advice given may be subject to local or national regulations, and that terminal operators have their own safety procedures which could affect cargo handling operations and the measures to be adopted in emergencies. The Master and all personnel must be aware of and comply with those regulations and procedures. Their existence will be highlighted by the use of the Ship/Shore Safety Checklist included in Appendix 3 of this Guide which, together with its guidelines for completion, remains a fundamental part of establishing safe conditions for transport by sea of chemicals in bulk.

4

TANKER SAFETY GUIDE (CHEMiCAL5)

ACKNOWLEDGMENTS This edition of the ICS Tanker Safety Guide (Chemicals) continues the tradition of providing a consolidation of experience and best operating practice in the chemical tanker industry. Its production would not have been possible without the assistance of those i ndividuals, companies and organisations that have so generously given thei r time and expertise to ensure its accuracy in the interests of the safe carriage of chem icals by sea. Special gratitude is expressed to the dedicated members of the technical working group, who spent many meetings making sure that the text was both accurate and that it reflects industry best practice - Toralf S0renes of Odfjell (Chairman of the group), Arjan Kreuze of Jo Tankers, Bruno Caillard representi ng Armateurs de France, Jan Sloth M0ller of Maersk, Keith Dean of Stolt Tankers, Leif Gunnar Alvaer of Odfjell, Per Tyrsted Jorgensen of Eitzen Chemical, Per Winther Christensen of the Danish Shipowners' Association and Peter Maasland of Shell. Particular mention is also made of the following i ndustry associations: the Chemical Distribution Institute (COi), the International Parcel Tankers' Association (IPTA), the International Association of lndependant Tanker Owners (lntertanko) and th e Oil Companies International Marine Forum (OCIMF). These organisations have ki ndly provided a 'peer review' of the fourth edition in order to verify that the contents meet the needs of the wider industry and their advice and comments have been carefully considered in the d rafti ng of this industry publication.

5

CONTENTS PAGE

6

FOREWORD TO THE FOURTH EDITION

3

PURPOSE AND SCOPE

4

DEFINITIONS

15

CHAPTER 1 - HAZARDS AND PROPERTIES OF CHEMICALS

21

1.1

Introduction

23

1.2 1.2.1 1.2.2 1.2.3 1.2.4 1.2.5 1.2.6 1.2.7 1.2.8

Physical Properties Density and specific gravity Volume expansion coefficient Melting point Vapour pressure

23

Boiling point Vapour density Viscosity Water solubility

1.3 1.3.1 1.3.2

Flammability Flash point Explosive/flammable limits

26 26 26

1.4 1.4.1 1.4.2 1.4.3 1.4.4 1.4.5 1.4.6

Static Electricity General Charge accumulation and relaxation in liquids Generation of static Static generation during cargo operations Static generation during tank cleaning Static generating portable equipment

28 28 28 28 29 29 29

1.5 1.5.1 1.5.2 1.5.3 1.5.4 1.5.5

Toxicity General

30 30 30 30 31 31

Exposure to toxicity Degrees of toxicity Exposure limits Precautionary principles

1.6 1.6.1 1.6.2 1.6.3 1.6.4 1.6.5 1.6.6 1.6.7

Chemicals that react with oxygen Chemicals that react with water Reaction of acids w ith water Incompatible chemicals Reaction with construction materials

1.7 1.7.1 1.7.2

Corrosive Substances General IBC Code requirements

Reactivity General Unstable chemicals

TANKER SAFETY GUIDE (CHEMiCAL5)

23 23

24 25 25 25 25 26

31 31

32 34 34 35 35

37 37 37 38

1.8 1.8.1 1.8.2 1.8.3

Hazardous Cargo Information Material Safety Data Sheet Contents of a Material Safety Data Sheet Inhibited cargoes

CHAPTER 2 - GENERAL PRECAUTIONS 2.1

38 38 38 39

41

Introduction

43

2.2

Moorings

43

2.3

Emergency Towing -off Pennants (Fi rewires)

43

2.4 2.4.1 2.4.2 2.4.3 2.4.4

Access to the Ship Means of access (gangways or accommodation ladders) Lighting Unau1horised persons Persons smoking or intoxicated

43 43

2.5 2.5.1 2.5.2

Warning Notices Permanent Temporary

44 44 44

2.6 2.6.1 2.6.2

Effects of Other Ships and Berths Other tankers at adjacent berths Chemical carrier operations at general cargo berths

45 4S 4S

2.7 2.7.1 2.7.2 2.7.3 2.7.4

Weather Precautions Wind conditions Electrical storms Cold weather Openings to the accommodation

45 4S 4S 4S 46

2.8 2.8.1 2.8.2 2.8.3

Machinery Spaces Funnel sources of ignition Blowing boiler tubes Cargo vapour

46 46 46 46

2.9 2.9.1 2.9.2

Pressure Surges Introduction Generation of pressure surge

47 47 47

2.10 2.10.1 2.10.2

Pumprooms and Enclosed Spaces Cargo pumprooms Enclosed spaces

48

2.11

Ship's Readiness to Move

48

2.12

Helicopter Operations

48

2.13 2.13.1 2.13.2 2.13.3 2.13.4

Communication Equipment Ship's radio transmission equipment Electrical maintenance and repairs Transmitting devices Personal electronic items

49 49 49 49

2.14 2.14.1 2.14.2 2.14.3 2.14.4 2.14.S 2.14.6 2.14.7

Hot Work General Assessment of hot work Hot work permit Preparation for hot work Checks by officer responsible for safety during hot work Action on completion of hot work Hot work flow chart

44 44 44

48 48

so 50

so so Sl Sl S2 S2 S3

7

2.15

Cold Work

54

2.16

Mechanically Powered Tools

54

2.17

Hand Tools

54

CHAPTER 3 - SAFETY MANAGEMENT, TRAINING AND PPE

8

SS

3.1

Introduction

57

3.2 3.2.1 3.2.2

Impl ementing a Safety Culture What is a safety culture? Key features of an effective safety culture

57 57 58

3.3

The ISM Code

58

3.4

Company Responsibility

58

3.5

Safety Information for Shore Personnel

59

3.6

Outside Contractors

59

3.7 3.7.1 3.7.2 3.7.3

Risk Management Risk assessment terms Conducting risk assessments Risk assessment matrix

59 60 60 61

3.8 3.8.1 3.8.2

Safe Operations Routine operations Non-routine operations

61 61 62

3.9

Incident Investigations

63

3.10 3.1 0.1 3.1 0.2 3.1 0.3 3.1 0.4 3.1 0.5 3.1 0.6 3.1 0.7 3.1 0.8 3.1 0.9 3.1 0.10

Ship's Manning Responsibility Familiarisation Tanker specific training requirements Basic tanker training Advanced tanker training Crew communication Drills and exercises Crew schedules and minimum hours of rest Summary of STCW requirements - hours of work and rest Prevention of drug and alcohol abuse

63 63 64 64 64 65 65 66 66 66 67

3.11 3.11 .1 3.1 1.2 3.1 1.3 3.11 .4 3.1 1.5 3.11 .6 3.11 .7 3.1 1.8 3.11 .9 3.11 .10 3.1 1.11 3.11 .12 3.11 .13 3.1 1.14 3.11 .15 3.11 .16 3.1 1.17

Personal Protective Equipment (PPE) Atmosphere monitoring equipment Safe working clothing Protective clothing Toxic or corrosive substance protection Chemical resistant clothing (protective suits) Types of chemical resistant clothing Eye protection Hand protection Foot protection PPE matrix Respiratory protection Canister or filter type respirators Self-Contained Breathing Apparatus (SCBA) Air line breathing system Emergency escape respiratory protection Maintenance Training

67 67 68 68 68 69 69 73 73 73 73 74 74 74 75 75 75 75

TANKER SAFETY GUIDE (CHEMiCAL5)

CHAPTER 4 - REGULATORY FRAMEWORK

77

4.1

Introduction

79

4.2

Regulatory Guidelines

79

4.3 4.3 .1

IMO MARPOL Regulations MARPOL Annex I - Prevention of Pollution by Oil MARPOL Annex II - Prevention of Pollution by Noxious Liquid Substances MARPOL Annex VI - Prevention of Air Pollution from Ships

79 80

83

4.4.1 4.4.2 4.4.3 4.4.4

IMO International Code for the Construction and Equipment of Sh ips carrying Dangerous Chemicals in Bulk (IBC Code) Tank types Summary of IBC Code requirements lnerting and padding Damage stability

4.5

Inert Gas Requirements for Chemical Carriers

87

4.6

IMO Ballast Water Convention

88

4.3 .2 4.3.3

4.4

CHAPTER 5 - SHIP AND EQUIPMENT

81

83

84 86 86

87

89

5.1

Introduction

91

5.2

cargo Tanks

91

5.3

Monitoring Equipment Introduction Alarms and shutdowns Air supply to control systems Liquid level gauges Overfill detection systems Pressure indicating devices Temperature monitoring equipment

92

Atmosphere Monitoring General General precautions Oxygen analysers Flammable gas detectors Toxic gas detectors

98 98 98

5.3 .1 5.3 .2 5.3.3 5.3.4 5.3.5 5.3 .6 5.3.7

5.4 5.4.1 5.4.2 5.4.3 5.4.4 5.4.5

5.5

92 93 94 94 96 96 97

99 100 101

103

5.5.1

cargo Pumps General

5.5.2 5.5.3 5.5.4 5.5.5

Oeepwell pumps Cargo pumprooms Booster pumps Emergency cargo pumps

5.6

Piping Systems and Valves

105

5.7

cargo Manifold

106

5.8

Venting Systems and P/V Valves

107

5.9

Vapour Return Systems

108

5.10

Heating and Cooling Systems

109

5.11

Tank Washing Systems Fixed tank washing machines Portable tank washing machines and hoses

110 110

5.11 .1 5.11 .2

103 103 104 104 105

111

9

5.12 5.12.1 5.12.2 5.12.3

Venting outlets

111 111 111 111

5.13 5.13.1 5.13.2 5.13.3 5.13.4 5.13.5 5.13.6 5.13.7 5.13.8

Inert Gas Systems Introduction Oxygen content Sources of inert gas Compressed nitrogen stored on board Liquid nitrogen stored on board Pressure swing adsorption (PSA) nitrogen generators Mem brane separation nitrogen generators Oil fired inert gas generators

112 112 112 113 113 114 114 114 115

5.14 5.14.1 5.14.2 5.14.3 5.14.4 5.14.5

Cargo Hoses Introduction Certification, marking and testing Storage and maintenance Operational use Cargo hose connections

115 115 115 115 116 116

5.15 5.15.1 5.15.2 5.15.3

Electrical Equipment and Installations in Hazardous Areas Introduction Certified safe electrical equipment Bonding and earthing

118 118 118 118

5.16

Ballast Pumprooms

119

5.17

Openings in Deckhouses and Superstructures

119

Gas Freeing Equipment Permanently installed gas freeing equipment Portable gas freeing equipment

CHAPTER 6 - CARGO OPERATIONS

10

121

6.1

Introduction

123

6.2 6.2.1

Responsibility Personnel and resources

123 123

6.3 6.3.1 6.3.2 6.3.3 6.3.4 6.3.5

Planning Cargo Operations Introduction Cargo information IMO Certificate of Fitness Stowage planning Specific cargo handling requirements

124 124 124 124 125 125

6.4 6.4.1 6.4.2 6.4.3 6.4.4 6.4.5

Preparation for Cargo Operations Introduction Pre-arrival information exchange Cargo handling plan Ship's personnel Preparing the cargo system prior to arrival

128 128 128 129 130 131

6.5 6.5.1 6.5.2 6.5.3 6.5.4

Port Arrival Procedures Pre-transfer meeting Ship/shore communications during cargo operations Ship/Shore Safety C hecklist Action prior to commencing transfer operations

133 133 134 134 134

6.6

Monitoring cargo Operations

135

6.7 6.7.1

Cargo Transfer Operations Inspection of cargo tanks prior to loading

136 136

TANKER SAFETY GUIDE (CHEMICALS)

Sampling and gauging Sample management Sampling systems Sample storage Ballasting and deballasting in port Clearing shore pipelines Completion of transfer Disconnection of cargo hoses Cargo unloading lnerting and tank atmosphere control during unloading Sweeping of cargo residues Completion of discharge

137 138 139 140 140 141 141 142 143 144 14S 14S 146 147 147 148 149 149 149 149 1SO

6.8 6.8.1 6.8.2 6.8.3 6.8.4 6.8.5 6.8.6

cargo care During the Voyage Tank integrity Tank venting Temperature controlled cargoes Inhibited cargoes Maintaining an inert atmosphere during the voyage Ballasting cargo tanks

151 1Sl 1Sl 1Sl 1Sl 1S2 1S2

6.9 6.9.1 6.9.2 6.9.3 6.9.4 6.9.5 6.9.6 6.9.7 6.9.8

Sh ip to Ship Transfer General

152 1S2 1S3 1S3 1S4 1S4 1S4 1S4 1SS

6.7.2 6.7.3 6.7.4 6.7.5 6.7.6 6.7.7 6.7.8 6.7.9 6.7.10 6.7.11 6.7.12 6.7.13 6.7.14 6.7.1s 6.7.16 6.7.17 6.7.18 6.7.19 6.7.20 6.7.21 6.7.22

Manifold connections Cargo loading Ship/shore electric currents Cargo pumprooms Correct operation of PN valves Vapour return and vapour balancing Tank atmosphere control Dangers of pressurised loading Topping off procedure

Responsibility Communications Navigational warnings Weather conditions and limitations Pre-transfer preparations on each ship Cargo transfer operations Completion of cargo transfer

CHAPTER 7 - INERT GAS AND NITROGEN SAFETY

157

7.1

Introduction

159

7.2

Dangers of Nitrogen

159

7.3

Safe Operations Involving Nitrogen

160

7.4 7.4.1 7.4.2 7.4.3 7.4.4 7.4.5 7.4.6 7.4.7 7.4.8 7.4.9

lnerting Operations lnerting definitions Maintenance of an inert atmosphere

161 161 161 162 162 163 163 163 163 163

lnerting tanks containing cargo lnerting empty tanks Loading inerted tanks Maintaining inerted tanks during the voyage Maintaining an inert atmosphere during unloading Tank cleaning and gas freeing under inert conditions Nitrogen supplied from shore

11

CHAPTER 8 - TANK CLEANING AND GAS FREEING 8.1

Introduction

169

8.2

Procedures and Arrangements Manual

169

8.3 8.3.1 8.3.2 8.3.3 8.3.4

Supervision and Preparation Responsibility Tank cleaning plan Pre-cleaning meeting Preparations

169 169 169 170 170

8.4 8.4.1 8.4.2 8.4.3 8.4.4 8.4.5 8.4.6 8.4.7 8.4.8

Cargo Tank Washing and Cleaning General Tank washing atmospheres Prevention of toxic exposure during tank cleaning Prevention of static generation during tank cleaning Tank washing in an inert atmosphere Tank washing in a non-inert atmosphere Precautions for sounding tanks Transfer of wash water to slop tanks

171 171 171

8.5 8.5.1 8.5.2 8.5.3 8.5.4 8.5.5 8.5.6 8.5.7

Special Cleaning Methods Introduction Reactive cargoes Manual cleaning Use of tank cleaning additives Steaming Recirculation washing Cleaning or gas freeing of cargo from non-cargo spaces

174 174 175 175 176 176 176 176

8.6 8.6.1

Monitoring Tank Cleaning Operations Precautions for sounding tanks when not using a sounding pipe

177 177

8.7 8.7.1 8.7.2 8.7.3

Arrangements for the Disposal of Tank Washings and Sl ops General Management of slops Mandatory prewash water

177 177 177 177

8.8

Tank Clean ing in Port

178

8.9

Tank Clean ing Equipment

178

8.10 8.10.1 8.10.2

Gas Freeing Safe procedures for gas freeing after tank cleaning and cleaning by ventilation Opening up of cargo lines and handling equipment

178 178 179

CHAPTER 9 - ENTRY INTO ENCLOSED SPACES

12

167

172 172 173 173 174 174

181

9.1

Introduction

183

9.2 9.2.1 9.2.2 9.2.3 9.2.4

Hazards Oxygen deficiency Toxic and/or flammable gases Presence of inert gas including nitrogen Oxygen enrichment

183 185 185 185 185

9.3

Atmosphere in Enclosed Spaces

186

9.4 9.4.1 9.4.2

Requirements for Enclosed Space Entry Planning Entry permit

186 187 187

TANKER SAFETY GUIDE (CHEMICALS)

9.5

Testing Before Entry

189

9.6 9.6.1

Enclosed Space Entry Entry into enclosed spaces other than cargo tanks

190 191

9.7

Work in Enclosed Spaces

191

9.8

Entry into an Enclosed Space where the Atmosphere is Known or Suspected to be Unsafe

192

9.9 9.9.1 9.9.2 9.9.3 9.9.4 9.9.5

Rescue from Cargo Tanks and Other Enclosed Spaces General

193 193 193 193 194 195

Preventing enclosed space accidents Rescue and recovery organisation The rescue operation Rescue and recovery equipment

CHAPTER 10 - EMERGENCY PROCEDURES

197

10.1

Introduction

199

10.2 10.2.1 10.2.2 10.2.3 10.2.4

Emergency Organisation Emergency team Supporting crew Emergency organisation in port Vacating a berth or terminal in an emergency

199 199 199 200 200

10.3 10.3.1 10.3.2 10.3.3 10.3.4 10.3.5 10.3.6 10.3.7 10.3.8 10.3.9

Fire-Fighting Equipment General Water Foam Foam monitors Carbon dioxide Halon Dry powder Inert gas systems Fire-fighting clothing

200 200 200 201 201 201 201 202 202 202

10.4 10.4.1 10.4.2 10.4.3 10.4.4

Responding to Emergencies Emergencies involving fire Emergency response to fire Fires involving chemicals Action to take in the event of fire

202 202 203 203 204

10.5 10.5.1 10.5.2 10.5.3 10.5.4

Other Emergencies Chemical cargo spills Deck valve and deck pipeline leakage Tank leakage within the vessel Emergency discharge or jettison of cargo

204 204 205 206 206

10.6

Notification of Spillage

207

10.7 10.7.1 10.7.2 10.7.3 10.7.4 10.7.5

Exposure to Chemicals Planning Medical first aid guides Toxic cargoes and antidotes Medical first aid after exposure to chemicals Emergency information on MSDS

207 207 207 207 208 208

10.8

First Aid and Further Care

209

13

APPENDICES

211

Appendix 1

Visitor Information Card

213

Appendix 2

Hot Work Permit

216

Appendix 3

Ship/Shore Safety Checklist

220

Appendix 4

Ship/Shore Safety Checklist Guidelines

227

Appendix S

Material Safety Data Sheet (MSDS)

245

Appendix 6

Inhibited Cargo Certificate

2S1

Appendix 7

Enclosed Space Entry Permit

2S2

Appendix 8

Cargo Hose Record

2S6

Appendix 9

Flexible Hose Test Certificate

2S7

Appendix 10

PPE Matrix

2S8

Appendix 11

Relevant Industry Publications

2S9

INDEX

14

TANKER SAFETY GUIDE (CHEMICALS)

261

DEFINITIONS For the purpose of this Guide the following interpretations apply. Administration (flag state)

The maritime administration of the country in which the ship is registered. This is the authority that is responsible for the issuance of statutory certificates related to the operation of a ship, and is responsible for inspections to ensure compliance with appropriate standards.

Administration (port state)

The administration of the country in which a port is situated.

Approved equipment

Equipment of a design that has been tested, approved and certified by an appropriate authority, such as a flag state administration or classification society, as safe for use, for example, in a specified hazardous atmosphere.

Asphyxia

The condition arising when the blood is deprived of an adequate supply of oxygen so that loss of consciousness may follow.

Asphyxiant

A gas or vapour, which may or may not have toxic properties, which when present in sufficient concentrations excludes oxygen and leads to asphyxia.

Auto-ignition temperature

The lowest temperature to which a solid, liquid or gas needs to be raised to cause self-sustaining combustion without initiation by a spark or flame or other source of ignition.

Boiling-Liquid/Expanding Vapour Explosion (BLEVE)

An explosion typically resulting from a catastrophic failu re of a vessel containing a liquid significantly above its boiling point at normal atmospheric pressure.

Boiling point

The temperature at which the vapour pressure of a liquid equals that of the atmosphere above its surface; this temperature varies with pressure.

Bonding (electrical)

The connecting together of electricity conducting metallic objects to ensure electrical continuity.

Cargo area

That part of the ship which contains the whole cargo system, cargo pump rooms, and includes the full beam deck area over the length of the ship above the cargo containment system. Where fitted, the cofferdams, ballast or void spaces at the after end of the aftermost cargo space - or the forward end of the forward most cargo space - are regarded as being excluded from the cargo area.

Cargo operations

Any operations involving the handling of cargo, tank cleaning, purging or venting etc.

Cargo transfer

The transfer of cargo to or from the ship.

Cavitation

Uneven flow caused by vapour pockets within a liquid .

15

Certificate of Fitness

A certificate issued by the flag administration confirming that the structure, equipment, fittings, arrangements and materials used in the construction of a chemical carrier are in compliance with the IMO IBC Code. Such certification may be issued on behalf of the administration by approved classification societies.

Certified gas free (see also Gas free)

A term signifying that a tank, compartment or container has been tested by an authorised person using an approved testing instrument, and found to be in a suitable condition - i.e. not deficient in oxygen and sufficiently free from toxic and chemical gases - for a specified activity, such as tank entry.

Certified safe el ectrical equipment Chemical absorption detector

(See Approved equipment)

An instrument used for the detection of gases or vapours which works on the principle of a reaction between the gas and a chemical agent in the apparatus; the gas discolours the agent or the agent dissolves some of the gas.

Closed gauging system (closed ullaging)

A system in which the contents of a tank can be measured by means of a device which penetrates the tank, but which is part of a c.losed system preventing the release of tank contents.

Cofferdam

The isolating space between two adjacent steel bulkheads or decks; it may be a void or ballast space.

Combustible gas detector

An instrument for detecting a flammable gas/air mixture and usually measuring the concentration of gas in terms of its Lower Flammable Limit (LFL). No single instrument is reliable for all combustible vapour.

Enclosed space

A space which has any of the following characteristics: l imited openings for entry and exit; Inadequate ventilation; or Is not designed for continuous worker occupancy, and includes, but is not limited to, cargo spaces, double bottoms, fuel tanks, ballast tanks, cargo pump rooms, cargo compressor rooms, cofferdams, cha in lockers, void spaces, duct keels, inter-barrier spaces, boilers, engine crankcases, engine scavenge air receivers, sewage tanks, and adjacent connected spaces. This list is not exhaustive and a list should be produced on a ship by ship basis to identify enclosed spaces.

Explosion proof/flame proof equipment

Equipment or apparatus which will withstand, without damage and in accordance with its prescribed rating (including recognised overloads), any explosion of a prescribed flammable gas to which it may be subjected under practical operating conditions and which will prevent the transmission of flame to the surrounding atmosphere.

'Expl osimeter'

11>

TANKER SAFETY GUIDE (CHEMICALS)

(See Combustible gas detector)

Filling limit (or ratio)

That volume of a tank, expressed as a percentage of the total volume, which can be safely filled, having regard to the possible expansion (and change in density) of the liquid.

Flame arrester

A device used in gas vent lines to arrest the passage of flame into enclosed spaces.

Flame proof equipment

(See Explosion proof equipment)

Flame screen (gauze screen)

A portable or fitted device incorporating one or more corrosion resistant wire woven fabrics of very small mesh used for preventing sparks from

entering a tank or vent opening, or for a short period of time preventing the passage of flame, yet permitting the passage of gas (not to be confused with Flame arrester). Flammable

Capable of being ignited and burning in air.

Flammable gas

A vapour/air mixture within the flammable range.

Flammable limits

The minimum and maximum concentrations of vapour in air which form explosive (flammable) mixtures are known as the Lower Explosive Limit (LEL) and Upper Explosive Limit (UEL) respectively. (For the purpose of this Guide, these terms are synonymous with Lower Flammable Limit (LFL) and Upper Flammable Limit (UFL) respectively.)

Flammable range

The range of flammable vapour concentrations in air between the lower and upper flammable limits. Mixtures within this range are capable of being ignited and burning.

Flash point

The lowest temperature at which a liquid gives off sufficient vapour to form a flammable mixture with air near the surface of the liquid or within the apparatus used . This temperature is determined by laboratory testing in a prescribed apparatus.

Gas absorption detector

(See Chemical absorption detector)

Gas dangerous space or zone

A space or zone within the cargo area which is designated as likely to contain flammable vapours and which is not equipped with approved arrangements to ensure that its atmosphere is maintained in a safe condition at all times.

Gas detector

An instrument which alerts someone to the presence of gas, especially in spaces where gas is not normally expected.

Gas free

Gas free means that a tank, compartment or container has been tested using approved gas detection equipment and found to be sufficiently free, at the time of the test, from toxic, flammable or inert gases for a specified activity, such as tank entry.

Gas freeing

Gas freeing means the process where a portable or fixed ventilation system is used to introduce fresh air into a tank in order to reduce the concentration of hazardous gases or vapours to a level safe for tank entry.

17

18

Gauze screen

(See Flame screen)

Hot work

Work involving flames, incendive sparks or temperatures likely to be sufficiently high to cause ignition of flammable gas. The term includes any work involving the use of welding, burning or soldering equipment, blow torches, some power driven tools, portable electrical equipment which is not intrinsically safe or contained in an explosion proof housing, and equipment with internal combustion engines.

Hot work perm it

A document issued by a person authorised by the Master permitting specific work to be done, for a specified time in a defined area, employing tools and equipment which could cause ignition of flammable gas (see Hot work).

IMO

The International Maritime Organization is the United Nations specialised agency responsible for developing international regulations for safety at sea and pollution prevention.

lncendive spark

A spark of sufficient temperature and energy to ignite flammable gas.

Inert gas

A gas (e.g. nitrogen) or mixture of gases containing insufficient oxygen to support combustion.

lnerting

The introduction of inert gas into a space to reduce and maintain the oxygen content at a level at which combustion cannot be supported.

Inflammable

(See Flammable)

Inhibited cargo

A cargo which contains an inhibitor.

Inhibitor

A substance used to prevent or retard cargo deterioration or a potentially hazardous chemical self-reaction, e.g. polymerisation.

Insulating flange

An insulating device placed between metallic flanges, bolts and washers, to prevent electrical continuity between pipelines, sections of pipelines, hose strings and loading arms, or equipment/apparatus.

Intrinsically safe

Intrinsically safe equipment, instruments, or wiring that are incapable of releasing sufficient electrical or thermal energy, under normal or abnormal conditions, to cause ignition of a specific hazardous atmospheric mixture in its most easily ignited concentration.

lower Explosive limit

LEL (see Flammable limits)

lower Flammable limit

lfl (see Flammable limits)

MAK

MAK values are daily eight hour time weighted average allowable values for exposure to chemicals in the workplace applicable to healthy adults.

MARPOL

International Convention for the Prevention of Pollution from Ships.

TANKER SAFETY GUIDE (CHEMICALS)

Material Safety Data Sheet (MSDS)

Document containing information and instructions on hazardous materials. A MSDS contains details about hazards and risks relevant to the substance, requirements for its safe handling, and actions to be taken in the event of fire or exposure to the product. MSDS is synonymous with SOS.

Oil Discharge Monitoring Equipment (ODME)

COME is equipment required on oil tankers as part of the approved oil discharge and monitoring control system. It is used to m onitor the discharge into the sea of oily ballast or other oil contaminated water from the cargo tank areas.

OH

Occupational Exposure l imits (OELs) are intended to help to control exposure to dangerous substances in the workplace, by setting the maximum amount of (air) concentration of a substance that can safely be allowed. The average exposure time in OEL lists is normally eight hours per day (often referred to as TWA-Sh or Time Weighted Average - Sh).

Oxygen analyser

An instrument used to measure oxygen concentrations, expressed as a percentage by volume.

Oxygen level in atmosphere

Throughout this Guide the percentage of oxygen in air is referred to as 21 %, since most instrumentation in use on ships has a gauge or scale which reads to 21 % . Strictly, however, the percentage of oxygen falls several hundredths of a percent below that figure, variously quoted between 20.85% and 20.95%.

Padding

Filling and maintaining the cargo tank and associated p'iping system with an inert gas - or other gas, vapour or liquid - in order to separate the cargo from air.

Polymerisation

The phenomenon by which the molecules of a particular compound link together into a larger unit containing anything from two to thousands of molecules, the new unit being called a polymer.

Purging

Purging means the introduction of inert gas into a tank which is already in an inert condition with the object of further reducing the oxygen content and/or reducing the content of existing hydrocarbon or other flammable vapours to a level below which combustion cannot be supported if air is subsequently introduced into the tank.

Relative vapour density

The mass of the vapour compared w ith the mass of an equal volume of air, both at standard conditions of temperature and pressure. Thus vapour density of 2.9 means that the vapour is 2.9 times heavier than an equal volume of air under the same physical conditions.

Responsible officer

The Master or any officer to whom the Master may delegate responsibility for any operation or duty.

Responsible terminal representative

The shore supervisor in charge of all operators and operations at the terminal associated with the handling of products, or responsible delegate.

Restricted gauging system (also known as restricted ullage system)

A system employing a device which penetrates the tank and which, when in use, permits a small quantity of cargo vapour or liquid t o be released. When not in use the device is completely closed.

19

Sloshing

Wave formations which may arise at the liquid surface in a cargo tank from the effects of ship motions.

SOLAS

International Convention for the Safety of Life at Sea.

Span gas

A vapour sample of known composition and concentration used to calibrate (or span) a ship's gas detection equipment.

Specific gravity

The ratio of the weight of a volume of a substance at a given temperature to the weight of an equal volume of fresh water at the same temperature or at a different given temperature. (Since temperat ure affects volume, the

temperature at which a specific gravity comparison is made needs to be known and is stated after the ratio.) Static electricity

The electrical charge produced on dissimilar materials through physical contact and separation.

Threshold limit Value

The 'time weighted average' (fWA) concentration of a substance to which it is believed workers may be repeatedly exposed, for a normal eight hour working day and 40 hour working week, day after day, without adverse effect. It may be supplemented by a 'short-term exposure limit' (STEL).

(TLV)

Toolbox talk

A short informal safety talk at the workplace prior to conducting planned work. Its objective is to raise awareness of all relevant aspects of the planned work, and particularly to discuss procedures and safety requirements.

Tripartite agreement

Where it is proposed to carry a liquid substance in bulk which has not been included in the IBC Code, the appropriate authorities invol ved in the proposed operation must establish and agree on a provisional assessment for the proposed operation on the basis of the guidelines referred to in MARPOL Annex IVReg. 6.2 and m ust notify the IMO of the agreements. When the tripartite agreements have been notified to the IMO, the agreements of the assessments for the products (or trade names) are issued in the form of MEPC .2/Circular.

20

Upper Explosive limit

UEL (see Flammable limits)

Upper Flammable limit

UFL (see Flammable limits)

Vapour density

(See Relative vapour density)

Vapour pressure

The pressure exerted by the vapour above the liquid at a given temperature.

Ventilation

The process of maintaining in a space an atmosphere suitable for human access, by natural or mechanical means using a fixed or portable system.

Venting

The release of cargo vapour or inert gas from cargo tanks and associated systems.

TANKER SAFETY GUIDE (CHEMiCAL5)

CHAPTER 1 HAZARDS AND PROPERTIES OF CHEMICALS

1

HAZARDS AND PROPERTIES OF CHEMICALS

This chapter gives an introduction to the range of hazards normally associated with the properties of chemicals that are carried as cargoes, and the precautions necessary to minimise or avoid these hazards.

1.1

Introduction

1.2 1.2.1 1.2.2 1.2.3 1.2.4 1.2.5 1.2.6 1.2.7 1.2.8

Physical Properties Density and specific gravity Volume expansion coefficient Melting point Vapour pressure Boiling point

1.3 1.3.1 1.3.2

Flammability Flash point

1.4 1.4.1 1.4.2

Static Electricity General Charge accumulation and relaxation in liquids Generation of static Static generation during cargo operations Static generation during tank cleaning Static generating portable equipment

1.4.3 1.4.4 1.4.5 1.4.6

22

Vapour density Viscosity Water solubility

Explosive/flammable limits

TANKER SAFETY GUIDE (CHEM,CALS)

1.5 1.5.1 1.5.2 1.5.3 1.5.4 1.5.5

Toxicity General Exposure to toxicity Degrees of toxicity Exposure limits Precautionary principles

1.6 1.6.1 1.6.2 1.6.3 1.6.4 1.6.5 1.6.6 1.6. 7

Reactivity General Unstable chemicals Chemicals that react with oxygen Chemicals that react with water Reaction of acids with water Incompatible chemicals Reaction with construction materials

1.7 1.7.1 1.7.2

Corrosive Substances General IBC Code requirements

1.8 1.8.1 1.8.2 1.8.3

Hazardous Cargo Information Material Safety Data Sheet Contents of a Material Safety Data Sheet Inhibited cargoes

1.1

INTRODUCTION Chemical tankers are designed and equipped to transport a wide range of different cargoes and often carry a large number of products si multaneously. The operation of chemical carriers differs from that of oil tankers in that, on a si ngle voyage, a large number of cargoes with different properties and inherent hazards may be carried. In port, several products may be handled simultaneously at one berth, typically involvi ng such different operations as loading, discharging and tank cleaning. The transportation of bul k chemicals by sea not only requires purpose built ships and equipment, but also seafarers who have received specialist training, both theoretical and practical, i n order to understand the properties of the various chemicals and the potential hazards i nvolved in cargo operations. When planning the carriage of chemical cargoes it is essential that the ship's crew and the company managi ng the vessel are provided with a full specification of each cargo in order to ensure compliance with international stowage, handling and carriage requirements. Furthermore, the cargo details should provide the ship's crew with all of the information that they may require i n order to handle th e cargo safely and to mini mise the i mpact that cargo operations may have on the environment.

1.2

PHYSICAL PROPERTIES

1.2.1

DENSITY AND SPECIFIC GRAVITY Den sity is defined as the mass of a substance per unit of volume, u sually expressed in the standard (SI) unit kg/m 3. Specific gravity (SG) is the ratio of the mass of a product when measured against the mass of an equal volume of water. Because specific gravity is expressed as a ratio, it has no measurement units. However, the SG can vary according to the temperature of the product. It is quite common to see the SG quoted as 20•04·c. which refers to the density of the product at a temperature of 2o·c referenced against the den sity of water at a temperature of 4•c . This temperature reference is selected because water has its maximum density of 1,000kg/m ' at 4•c. For chemical carriers, design parameters specify the maxi mum density of products that can be carried in each cargo tank. The design strength can differ between various tanks on board the same ship, resulting in different maxi mum densities and maximum filling ratios. The information regarding tank strengthening can be found in th e classification society's specifications for the ship, and the Master should be familiar with any restrictions that may be imposed when loading high density cargoes. Especially important is the need to be aware of and avoid the risk of slack loading a tank. This is because slack loading can lead to sloshi ng forces that may cause damage to the tank structure or its internal fittings and equipment. Classification societies provide information about tank strength in various formats and the Master should ensure that the restrictions are understood and that there is full compliance.

1.2.2

VOLUME EXPANSION COEFFICIENT Whereas the mass of a product does not vary with temperat ure its volume gen erally expands with increasing temperature. As a consequence, the density will vary with tem perature. For petroleum products, volume correction factors are calculated using American Society for Testi ng and Materials (ASTM) tables.

23

For chemicals, density at standard temperature (usually 2o·c ) is converted to density at the actual temperature, usi ng the following fonmula:

Oa = Or + ((Tr - Ta) x OCF) Where: Oa = density at actual temperature (Ta) Or = density at reference temperature (Tr) OCF = density correction factorrc Density correction factors are usually not stated in the MSDS or commodity databases, and w ill typically be obtained from the loading master or cargo surveyor. For example: Methanol Dr at 2o·c = 0.7913 The OCF for methanol is 0.00092/'C What is the density (Oa) at 35•c? Oa = 0.7913 + ((20 - 35) x 0.00092) Oa = 0.7775

Sufficient space must be allowed in the tank for expected expansion of cargo during the voyage due to a rise in outside temperatures or of cargo bei ng similarly affected by heated cargoes in adjacent tanks. A useful formula for calculating the maximum volume of a cargo to be loaded in a tank (Vmax) is:

Vmax

= 0.98 V x (Omax/01)

Where:

1.2.3

0.98V

98% volume of the tank

Omax

Density of the cargo at the maximum expected temperature

DI

Density of the cargo at the loading temperature

MELTING POINT The melting point of a product is the temperature at which it changes from the solid to the liquid state. At the melting point, th e solid and liquid phases exist in equilibrium. The temperature of the reverse process when a product changes from a liquid to a solid is referred to as the freezing point or crystallisation poi nt. For most pure chemicals (which are products with a defined quality specification) the melting and freezing points are approximately equal. However, some products such as vegetable oils, creosote oil, lube oil additives and clean petroleum products, whose quality varies, do not have a defined melting poi nt but a melti ng range. Cargoes with a melting poi nt above the ambient tem perature of the ship's trading area will need to be heated in order to remain liquid. The structure and equipment of a ship can impose a limitation on the carriage of h eated cargoes, which should be documented on board. Exceeding this limitation could damage the cargo tank coating or coati ngs in adjacent spaces such as ballast tanks. Excessive heat will also create thermal stresses withi n the steelwork of the tank and risk structural damage. Caution should be exercised when carrying high heat products. Cargo in non-insulated pipes and vents may freeze. Should vent lines or vents be blocked structural damage may occur due to a vacuum or overpressure developi ng w ithin the tank.

24

TANKER SAFETY GUIDE (CHEMICALS)

1.2.4

VAPOUR PRESSURE The vapour pressure of a liquid is defined as the pressure exerted by its vapour when the liquid and vapour phase are i n dynamic equilibrium. In a closed system at constant temperature, liquid molecules are evaporating and vapour molecules are condensi ng, while the pressure remains constant . Vapour pressure increases with temperature, so when stating a vapour pressure it is also important to state the temperature. Vapour pressure is expressed in kPa (1 00 kPa = 1 bar= 14.5 psi = 0.99 atm). A product with a high vapour pressure at ambient temperatures is referred to as volatile.

1.2.5

BOILING POINT Boiling point is defined as the temperature at which the vapour pressure of a Ii quid equals the external pressure that is surrounding the liquid. The lower the external pressure the lower the temperature at which the product will boil. In a closed cargo tank, a liquid will boil when the vapour pressure is equal to the external pressure plus the pressure setti ng of the pressure/vacuum (PN) valve. The IBC Code requires that cargoes with a vapour pressure above 101.3 kPa at 37.8°( (in other words a boiling point below 37.8°() can only be loaded in tanks that have a mechanical cooling system or that are able to withstand th e vapour pressure of the cargo at 45•c.

1.2.6

VAPOUR DENSITY Vapour density is the ratio of the mass of a given volume of vapour relative to the mass of the same given volume of air. Air has an arbitrary vapour density of 1, which makes it very straightfoiward to see if a particular vapour is heavier or lighter than air. At constant pressure and temperature, vapour density is proportional to the molecular mass of the product. Most chemical cargoes h ave a molecular mass higher than air, which means that their vapours are heavier than air. Particular care must therefore be taken during cargo and tank cleaning operations because vapour concentrations are likely to accumulate in semi-enclosed areas at deck level and at the bottom of enclosed spaces.

1.2.7

VISCOSITY Viscosity is a measure of the resistance of a liquid to flow, o r i n more general terms it is the measure of the 'thickness' of the liquid. Ki nematic viscosity is a measure of the rate at which a known volume of liquid flows under the force of gravity at a specific temperature. It is measured in terms of surface area per unit of time, usually mm2/second, whereby 1 mm2/second is more commonly known as 1 centistoke (cSt). Dynamic viscosity measures the resistance of a liquid to flow under an applied force at a given temperature. It is equal to the kinematic viscosity multiplied by the density of the fluid and is expressed in millipascal-seconds (mPa.s). The viscosity of a cargo determines its pumping ch aracteristics and the amount of residue that may be left after unloading. For most products, viscosity decreases with increasing temperature. However, certain products show increased viscosity when heated due to changes withi n their chemical structures.

2S

1.2.8

WATER SOLUBILITY Solubility in water can either be expressed as a percentage or graded (i.e. 'nil', ' slightly' or 'complete'). Water solubility depends on the molecular polarity of the product and the number and length of carbon atoms within the molecule. Hydrocarbons such as paraffins and olefins are non-polar and insoluble in water (i.e. solubility< 0.01 %). Hydrocarbons containing oxygen, such as alcohols, ketones, acids, esters and ethers, tend to be more soluble in water as the length of the carbon chain is small (typically 3-4 maximum). As the number of carbon atoms in the hydrocarbon chain increases water solubility rapidly decreases. Solubility is also temperature dependant. For most products solubility increases at higher temperatures. A cargo with little or no solubility in water will form a separate layer above or below the water layer, depending on the density of the product relative to fresh water, which has a density of 1.00 tonnes/m'. Many water insoluble products have a relative density less than 1.00 and will float on top of water. The most common group of hydrocarbon cargoes that are heavier than water are chlorinated solvents which will sink to the bottom of the tank when mixed with water.

1.3

FLAMMABILITY

1.3.1

FLASH POINT Flash point is the lowest temperature at which a flammable liquid will produce enough vapour to form an ignitable mixture with the surrounding air. Every liquid has a vapour pressure, which is a function of temperature. However, not all liquids produce a flammable vapour. As the temperature of a flammable liquid increases, the vapour pressure rises and, as a result, the concentration of flammable vapour in the air also increases. Should the temperature of the liquid exceed the flash point, the threat of an explosion from an ignition source becomes real.

1.3.2

EXPLOSIVE/ FLAMMABLE LIMITS The explosive/flammable limits of any flammable liquid are defined as the range of concentration of flammable vapour (expressed as % by volume in air) in which an explosion can occur upon ignition. It is the oxygen in air which mixes w ith the flammable vapour to create an explosive mixture. At the bottom of the range is the lower explosive/flammable limit (U:ULFL), below which there is insufficient flammable vapour in the air to support combustion. At the top of the range is the upper explosive/flammable limit (UEUUFL), above which there is insufficient air within the flammable vapour to support combustion. Mixtures of flammable vapours and air which fall between the LEL and the UEL are explosive and are easily ignited by an ignition source. The flammable range of certain chemicals is greater than for oil cargoes. For example, methanol has a flammable range of 30% (LFL 6% to 36% UFL). This, together with other characteristics (low flash point, low boiling point and high vapour density) dictates that special precautions are taken in the handling of such cargoes. It should be noted that the terms 'explosive limit' and 'flammable limit' are for p ractical sh ipboard purposes synonymous.

26

TANKER SAFETY GUIDE (CHEM,CALS)

15

.,

F

~ '-' .... I ',

E J

0 10 >

>

t: ~

I .€ I

.D

""'

~ .,~

..

.. "~ ..~ 0

....

+

i::

.§ ~

............ '°¥v.~Q

', ..,..,,,.,1t1,

--.... . . .

I

C>;,.

'

aI

5

',,

- - ... . .L

G

I

c:

',

Flammable

mixtures

Critlca1 fJllutt ------With air on

HA-

Dilution-:M~J----

E

T -------.. ..:____ :::.:-:::::::::::::---

":c>

c A

0

5

10

15

20

21

Oxygen - Percentage by Volume

Figure 1.1 - Flammability Composition Diagram - Hydrocarbon Gas/Air/Inert Gas Mixture This diagram is illustrative only and should not be used for deciding upon acceptable gas compositions in practical cases.

The effect of inert gas on flammability When an inert gas is added to a hydrocarbon gas/ai r mixture, the result is to increase the Lower Flammable Limit hydrocarbon concentration and to decrease the Upper Flammable Limit concentration. These effects are illustrated in Figure 1.1, which should be regarded only as a guide to the principles involved. Every poi nt on the diagram represents a hydrocarbon gas/air/inert gas mixture, specified in terms of its hydrocarbon and oxygen content. Hydrocarbon gas/air mixtures without inert gas lie on the line AB, the slope of which reflects the reduction in oxygen content as the hydrocarbon content increases. Points to the left of the line AB represent mixtures with their oxygen content further reduced by the addition of inert gas. The lower and upper flammability limit mixtures for hydrocarbon gas in air are represented by the points C and D. As the inert gas content increases, the flammable limit mixtures change as indicated by the lines CE and DE, which finally converge at the point E. Only those mixtures represented by points in the shaded area within the loop CEO are capable of burning. On this diagram, changes of composition due to the addition of either air or inert gas are represented by movements along straight lines directed either towards the point A (pure air), or towards a point on the oxygen content axis corresponding to the composition of the added i nert gas. Such lines are shown for the gas mixture represented by the point F. It is evident from Figure 1.1 that, as inert gas is added to hydrocarbon gas/air mixtures, the flammable range progressively decreases until the oxygen content reaches a level, generally taken to be about 11% by volume, when no mixture can burn. The figure of 8% by volume of oxygen, specified by SOLAS for a safely inerted gas mixture, allows a margin beyond this value.

27

When an inerted mixture, such as that represented by the point F, is diluted by air, its composition moves along the line FA and therefore enters the shaded area of flammable mixtures. This means that all inerted mixtures in the region above the line GA go through a flammable condition as they are mixed with air, for example, during a gas freeing operation. Those mixtures below the line GA, such as that represented by point H, do not become flammable on dilution. It should be noted that it is possible to move from a mixt ure such as F to one such as H by dilution with additional inert gas (i.e. purging to remove hydrocarbon gas).

1.4

STATIC ELECTRICITY

1.4.1

GENERAL Static electricity is the build up of an electrical charge on the surface of objects. Materials are usually electrically balanced with an equal number of positive and negative charges. When two unlike materials are in contact with each other these charges can flow from one to the other creating an imbalance in the number of positive and negative charges. This process is amplified by friction, for example when a cargo moves through a pipeline. Static charges build up on poor electrical conducting materials (insulators) where the charge cannot come into balance with its surroundings. When two materials with an accumulated static electrical charge are brought close together, the two charged surfaces will seek to equalise their potential. If the difference in potential is large enough there will be sufficient energy for the charge to jump the gap between the two materials and a spark will be generated.

1.4.2

CHARGE ACCUMULATION AND RELAXATION IN LIQUIDS The ability of different liquids to conduct electricity varies. The electrical conductivity of a liquid is measured in pico siemens (pS) per metre. Charge accumulation does not occur in liquids having conductivity well above 10 pS per metre. Such liquids are called non-accumulators or conductive materials, the most common being salt water which is a good conductor of electricity. However, at a conductivity of below 10 pS per metre, the accumulation of an electrical charge may be significant. l iquids of low conductivity are called static accumulators or non-conductive. For safety reasons, all liquids with a conductivity reading of less than SO pS per metre are considered to be non-conductive.

1.4.3

GENERATION OF STATIC The risk of generating static sparking can occur during the following operations on board a chemical carrier: 1. loading and unloading An electrostatic charge is generated within the liquid as it flows through pipelines. The amount of charge generated w ill depend on the ability of the liquid to conduct electricity, a property known as its electrical conductivity. 2. Steaming Injecting steam into a cargo tank during tank cleaning can cause a build up of static within the condensed water droplets. 3. Gas freeing Forced air gas freeing devices can cause a static charge to build up on the body of the equipment.

28

TANKER SAFETY GUIDE (CHEMiCAL5)

4. cargo tank cleaning A static charge will be produced when water is forced, under high pressure, through the nozzle of a tank cleaning machine. As a result, the water mist inside the cargo tanks may become charged . A charge can also build on the nozzle of the tank cleaning machine unless the machine is electrically grounded. 5. Sampling/gauging Objects such as ullage probes or sampling equipment may already contain an electrostatic charge prior to being lowered into a tank. Lowering and raising such equipment in and out of a cargo tank may also generate a static charge on the line. 6. cargo inhibitors Adding of substances such as powdered inhibitors and other similar material may generate a static charge especially if added by free falling the substance into the tank.

1.4.4

STATIC GENERATION DURING CARGO OPERATIONS A liquid flowing into a cargo tank can be charged by friction within the loading pipeline and remain charged within the cargo tank. The static charge within the cargo will slowly d issipate as the difference in potential between the cargo and the tank structure equalises. This process is called charge relaxation and its speed depends upon the conductivity of the liquid . Should the cargo contain water droplets, friction occurs when these droplets settle by gravity through the liquid in the tank (assuming that the liquid has a density less than that of water). Similarly, if the liquid contains a non-dissolved gas, the liquid could become charged when the gas bubbles rise to the surface of the liquid in the tank. In both of the above cases a vertical electrical current is established and a high voltage may result at the surface of the liquid, which is known as a surface voltage. Over time, depending on the conductivity of the liquid, the charge will equalise with the tank structure as described above. A static charge can also be generated if the liquid is allowed to fall freely into a cargo tank (splash filling), where friction with the air through which the liquid falls adds a further charge to the liquid. Charged foam, generated when splash filling some liquids, will retain a charge for a much longer time than the bulk of the liquid, as the thin film of foam bubbles at the liquid interface only provides a very narrow path for charge relaxation to the tank structure.

1.4.S STATIC GENERATION DURING TANK CLEANING A statically charged mist is formed inside the cargo tank when washing, particularly w ith hot water or a cleaning medium or when injecting steam into the tank. Friction is also generated within the tank cleaning machines at the nozzle, along the water jet and on impact against the tank surfaces. Statically charged mists can remain inside empty cargo tanks for a far longer ti me than the static charges generated within a liquid product during the loading and discharging process. Relaxation of a static charge within the mist can only happen as fast as the time it takes for the mist to condense on to the tank surface. Such high voltages can be generated within these mists that sparks can occur

even in air.

1.4.6

STATIC GENERATING PORTABLE EQUIPMENT When an insulated or unearthed electrode is immersed in an electrostatic field it becomes charged, but the charge has no path to earth. If the difference in electrical potential is large enough a spark can then jump from the electrode to the tank wall or to the surface of the liquid. If the atmosphere is flammable, ignition will occur.

29

Examples of such equipment used on deck that may act as an electrode i nclude metal sampling cans and portable pumps as well as ullaging and sounding equipment. The lines used to lower such equipment are also potential generators of static electricity, particularly ropes made of synthetic fibres. Ropes made of synthetic fibres should never be used to lower equipment into tanks.

1.5

TOXICITY

1.5.1

GENERAL Exposure to toxic or poisonous substances causes harm to human h ealth and in more extreme cases can lead to serious injury or death. Toxicity is an i ntrinsic property of a chemical and cannot be modified. Even the slightest exposure to a highly toxic substance can result in serious health problems. However, correct medical first aid treatment following exposure can mitigate the consequences. Generally there are three defined types of toxicity which relate to the nature of the substance:

1. Chemical This relates to specific ch emical compounds. The toxicity of such compounds or mixture of compounds is measured in terms of the exposure time n eeded to cause an effect.

2. Biological This relates to the effects of viruses and bacteria. Measuring the toxicity of such compounds is more complicated because it depends on th e effectiveness of the immune system of the person exposed.

3. Physical This relates to compounds that on their own are not specifically toxic, but which can be directly responsible for potentially life threatening consequences, for example the inhalation of dust from coal and asbestos.

1.5.2

EXPOSURE TO TOXICITY There are three ways where toxic poisons can enter the body: 1. By being swallowed (oral toxicity); 2. By absorption through the skin, eyes and mucous membranes (dermal toxicity); or 3. By inhalation as a vapour or mist (i nhalation toxicity). A chemical may be toxic by more than one of these routes. For example, toxic vapours and mists affect people mostly via the respiratory system, but they can also be absorbed through the ski n. A highly toxic substance is one where only a small quantity of the substance is n eeded before harm is caused. During ch emical carrier operations, contact with a liquid or inhalation of its vapour are the most likely forms of exposure. Safe operating procedures, a full understanding of the dangers i nvolved and the use of the correct Personal Protective Equipment (PPE) will all h elp to protect the crew from exposure to toxic products.

1.5.3

DEGREES OF TOXICITY Toxicity can be defined as acute, sub-acute or chronic: A substance with acute toxicity is sufficient to cause harm almost i mmediately after exposure. Substances commonly called poisons have extreme acute toxicity; A substance with sub-acute toxicity will only start to show symptoms after repeated exposure in doses too small to cause an i mmediate acute effect; or A substance has chronic toxicity if its effects only appear after repeated exposure over a period of time. Examples are substances which are carci nogenic (cancer inducing) such as benzene.

30

TANKER SAFETY GUIDE (CHEM,CALS)

1.5.4

EXPOSURE LIMITS An exposure limit is the maximum concentration of a chemical substance or vapour in air that a person can safely be exposed to, day after day, without suffering any adverse health effects. Exposure limits are generally expressed as a Threshold Limit Value (TLV). Various governmental bodies publish TLVs or similar terms to define an acceptable maxi mum regular working dose of a hazardous or toxic substance. These exposure limit definitions should not be regarded as the absolute dividing line between what is safe and what is a hazardous working environment. It is always good operating practice to keep vapour concentrations to an absolute minimum and well below the TLV. The most widely used TLVs are those issued by the American Council of Governmental and Industrial Hygienists (ACGIH). The values are updated annually i n the light of new knowledge, so it is always important to refer to the latest information issued by ACGIH. The ACGIH defines three categories of TLV: TLV - TWA (Time Weighted Average) The concentration of vapour i n air which may be experienced for an eight hour day or 40 hour week throughout a person's working life. This is the most commonly quoted TLV. TLV - STEL (Short Term Exposure Limit) The maxi mum concentration of vapour i n air allowable for a period of up to 15 minutes, provided that there are not more than four exposures per day and at least one hour between each. The STEL is always greater than the TWA. However, this figure is not always provided for all substances. TLV - C (Ceiling) The absolute maximum concentration of a vapour to which a person should be exposed which should never be exceeded . It is given only for fast acti ng substances. This is the highest of the three val ues for a given substance.

1.5.5

PRECAUTIONARY PRINCIPLES Safe containmen t is the first objective when handling any toxic substance. By ensuring that the chemical and its vapour are safely contai ned within the boundaries of the approved cargo system, and by the use of closed monitori ng and control systems, the crew will be protected effectively. Chemical carriers are designed to provide for the safe and secure handling and storage of toxic cargoes. However, accidents and failure of equipment can occur and therefore it is essen tial that the ship's containment systems are well maintai ned and tested on a regular basis in order to ensure that they work as designed. Some operations i nevitably i nvolve openi ng the system and potentially exposing the crew to toxic substances. Disconnecting cargo hoses at the manifold or while taki ng cargo samples are typical examples of where exposure can occur. Duri ng such operations, it is essential that crew members are properly protected by appropriate PPE.

1.6

REACTIVITY

1.6.1

GENERAL Most chemicals carried by sea are chemically stable and, provided that they are appropriately handled, can be loaded, stowed and discharged safely. Some chemicals, however, require special care to ensure that they remain in a stable condition. Reactive chemicals may be inh eren tly unstable or, when in contact with air, water or other materials may react in a dangerous and violent manner.

31

Dangerous reactions are those emitti ng heat, and those that generate hazardous vapours and gases. A reaction which produces heat is called an exothermic reaction. The speed of a reaction varies widely depending on the ch emicals involved but generally the reaction rate accelerates as heat is generated. A very fast reaction may cause an explosion. A chemical that must absorb heat to trigger a chemical reaction is known as endothermic. This does not usually present a hazard on board so long as the chemical is kept separated from a h eat source. For the sake of clarity reactive ch emicals are categorised as follows: Unstable or self-reacting chemicals, either decomposing or polymerisi ng; Chemicals capable of reacting with oxygen i n the air, either forming peroxides or liable to decomposition; Chemicals which react with water to emit dangerous gases; and Incompatible chemicals which react dangerously if mixed together.

1.6.2

UNSTABLE CHEMICALS Reaction characteristics Unstable chemicals can self-react withi n their own mass and do not need another substance to trigger a reaction. Decomposition or polymerisation is the most typical reaction that can occur within unstable chemicals carried on board chemical tankers. A compound may change from a free flowing liquid into a viscous one or even a solid. Polymerisation may occur spontaneously with no outside influence, or it may occur if the compound is heated, or if a catalyst or impurity is added. Polymerisation may, under some circumstances, be dangerous, but may be delayed or controlled by the addition of i nhibitors. Substances that polymerise may generate heat and/or toxic and flammable gases. Polymerisation is often i nitiated by high temperatures, or by a reaction w ith small amounts of other ch emical impurities that act as a catalyst which further accelerates the rate of reaction. The most common catalysts that accelerate polymerisation are acids, alkalis and metals. The mai n danger of exothermic polymerisation in a confined space is an increase in pressure, in addition to the emission of potentially toxic and flammable vapours. Polymerisation may be prevented by controlling the transport tem perature and by adding a chemical stabiliser or inhibitor, which neutralises the impact of the catalyst. Substances which polymerise, such as styrene monomer and vinyl acetate monomer, exhibit a unique property which allows individual molecules of a particular substance (monomer) to combine with each oth er to form long chain polymers. Most polymerisation reactions are exothermic, and are characterised by an accelerating reaction rate until all of the monomer molecules are consumed. The speed of a polymerisation reaction can be extremely dangerous.

If the polymerisation process starts spontaneously, the product is considered to be self-polymerising. Although spontaneous polymerisation can occur at ambient temperatures, it is very often i nitiated by elevated tem peratures, either due to environmental conditions or adjacent heat sources. Spontaneous polymerisation of a monomer cargo presents the following dangers: The generation of h eat which accelerates th e speed of the chemical reaction; The rapid volumetric expansion of the product causes over pressurisation of the cargo tank with a consequent danger of rupture of the containment system; The rupture of the tank may lead to ch emical reactions with other cargoes in adjacent cargo tanks;

32

TANKER SAFETY GUIDE (CHEMICALS)

While a monomer cargo may often be a light and volatile liquid in its stable form, the polymerisation process produces heavier and more viscous liquids, or even solids, which may block the tank vents so that the pressure inside the tank increases even further; and Once solidified the polymer occupies a greater volume than the corresponding volume of liquid monomer. Cargoes that polymerise will usually contain an inhibitor that stops the initiation of the polymerisation reaction. These inhibitors are designed to be effective for a set period of time at a specified temperature. It is therefore essential that the timed effectiveness of the i nhibitor is sufficient for the voyage and includes a good safety margin. Since elevated temperature can reduce the effectiveness of the inhibit or or reduce its effective ltte, it is essential that heat sources are kept away from these cargoes and that the temperature is closely monitored on at least a daily basis, or more frequently if recommended by the cargo manufacturer or shipper. An increase in cargo temperature th at is not related to ambient weather conditions or adjacent cargo temperatures may be an early i ndication that a polymerisation process has started. In such instances, the cargo manufacturers should be contacted immediately to advise appropriate counter measures which may i nclude the addition of more inhibitor or the cooling of adjacent structures. Should the increase in temperature be rapid then the decision to jettison cargo may be the only option in order to avoid serious structural damage to the cargo tank and the ship. Effect of inert gas on inhibited chemicals Inhibitors usually require oxygen to be effective and this is mainly obtained from oxygen dissolved withi n the product itself. Inhibitors may also require the presence of a certain percentage of oxygen in the tank atmosphere in order to be effective. It is good practice for this minimum level of oxygen to be stated on the inhibitor certificate. As a general rule, a cargo that contains an oxygen dependent inhibitor should not be inerted before loading or during carriage. If it is required to inert the cargo this should be carried out before unloading. Where products are carried w ithout inerting (tank size not greater than 3,000m 3) such cargo must not be carried in a tank requiring inerting under the requirements of SOLAS Chapter 11-2. If nitrogen is bubbled through an i nhibited cargo (such as when compressed nitrogen is used to clear the cargo hose after loading) the nitrogen will deplete the oxygen dissolved in the liquid, thereby requiring the inhibitor to take oxygen from the atmosphere, see also Section 6. 7.8. Should there be any doubt, additional advice should be sought from the shipper. IBC Code requirements The IBC Code specifies the precautions to be taken against spontaneous decomposition and polymerisation, by the use of additives (stabilisers and i nhibitors) uniformly distributed within the mass of the product, and by control of the carriage temperature. The IBC Code requires the manufacturer of the unstable chemical being carried, who may not necessarily be the shipper, to be responsible for providing the ship with a number of critical safety instructions concerning the additive. These i nstructions must be provided in the form of an inhibitor certificate showing: Which additive has been or should be introduced into the product, and in what quantities; When the additive was or should be introduced, and for how long it is expected to be effective; The temperature conditions to be met in order to preseive the effectiveness and lifetime of the additive; Whether dissolved oxygen must be present in the liquid for the i nhibitor to be effective; The oxygen concentration that is required within the ullage space in order for the i nhibitor to remain effective; and What action should be taken should the length of the voyage last longer than the effective lifetime of the additive.

33

Most inhibitors are not volatile in themselves, so they do not vaporise with th e cargo and are unlikely to be present i n cargo vapours. Therefore, wherever cargo vapours may condense, for instance inside vent valves and flame arresters, there is a risk that polymerisation may occur. The IBC Code also contains provisions agai nst th e exposure of cargoes to excessive heat. The preventive measures include prohibition of carriage in tanks or pipelines close to those used for products whose temperature is high enough to initiate a reaction in the unstable chemical, and a requirement to blank the tank's heating systems.

1.6.3

CHEMICALS THAT REACT WITH OXYGEN Reaction characteristics Some chemicals react w ith oxygen. These include ethers which react slowly with oxygen in the air, or with oxygen dissolved w ithin the mass of the liquid to form peroxides. Once formed, organic peroxides can act as reaction catalysts, initiating a polymerising reaction. The main danger is that at normal or elevated temperatures they are liable to trigger exothermic and self-accelerating decomposition. The decomposition can be initiated by h eat, contact w ith impurities (e.g. acids, heavy metal compounds and ami nes), friction or impact. Some organic peroxides may decompose explosively, particularly i n confined spaces such as a cargo tank. In order to prevent the formation of organic peroxides when carryi ng such cargoes, the tank should be fully i nerted for the duration of the voyage. A further precaution is ensuring that the carriage temperature is as close to ambient as possible. Natural products such as animal and vegetable oils react slowly with oxygen as a part of the decomposition process (also known as putrefaction). These oils slowly oxidise i n the presence of air by the action of bacteria present withi n the oils. There are two dangers associated with this decomposition process: The process consumes oxygen and produces carbon dioxide (CO,) creating an asphyxiating atmosphere; Hydrogen sulphide (H 2S), a hazardous gas, can be produced as part of th e decomposition process if oil is in contact w ith water. Tanks contai ning bunkers or slop tanks containing vegetable oil washi ngs are a particular risk, especially after prolonged storage over several days at elevated tem peratures. The process of decomposition is accelerated by h eat and the presence of water. IBC Code requirements For cargoes susceptible to the formation of peroxides, the IBC Code specifies measures to control the environment or atmosph ere inside cargo tanks, including the use of an inert gas. Inert gas with a very low level of oxygen is required and for this reason nitrogen is the preferred medium. The IBC Code requires sufficient inert gas to be available to purge air out of th e cargo system before loading. To compensate for losses during transport, in order to ensure that a positive over pressure is maintained i n the loaded tank, sufficient inert gas needs to be available so that the tanks can be topped up throughout the voyage. The cargo handling system for cargoes susceptible to the formation of peroxides should be independent of all others.

1.6.4

CHEMICALS THAT REACT WITH WATER Reaction characteristics The reaction of some chemicals with water, including humidity in the air, can generate gases that are flammable or toxic or both. lsocyanates, such as Toluene diisocyanate (TOI), react violently with water to form carbon dioxide, an asphyxiate gas. The reaction can also lead to over pressurisation of the tank.

34

TANKER SAFETY GUIDE (CHEMiCAL5)

In addition to the following IBC Code requirements for tanks, pumps, lines and vents, the segregation of heating coils/lines and purging lines should also be addressed. JBC Code requirements Products which, when in contact with water, emit dangerous gases should be kept totally separated from water, and be carried under a dry atmosphere. The IBC Code requires such products to be separated by two barriers from tanks containing water such as water tanks, ballast tanks (unless those tanks are empty and dry) or cargo tanks containing water based solutions. The same level of double separation requires that pipelines containing water (such as slop or ballast lines) should not pass through the tank, unless encased in a tunnel. If temperature control is required, neither steam nor water should be used to heat or cool the cargo. The entire cargo system (tank, pump, lines and vents) should be completely segregated from other cargo and ballast systems. The tank should not be cleaned with water unless the shipper of the product o r the shipowner has specified a safe procedure for doing so.

1.6.S

REACTION OF ACIDS WITH WATER Reaction characteristics The mixing of some acids with water greatly increases their corrosive effect and a violent reaction can occur. Company procedures should be followed when the passivation or pickling of stainless steel tanks takes place. When acids and alkalis (caustics) are mixed with water, energy is released in the form of an immediate increase in temperature. On dilution, such as when preparing solutions for passivating or tank cleaning, and in order to prevent a violent reaction, acids or alkalis should always be slowly added to water rather than water being added to the container of acids or alkalis. If water is added to acid or alkalis, the temperature may rapidly rise to above and cause splashing.

1oo·c

Concentrated sulphuric acid (95-98%) becomes corrosive to stainless steel when diluted between 20-80% . Corrosiveness is further enhanced when acid is diluted with sea water because of the high chloride content. When tank cleaning after discharge of a cargo of sulphuric acid, a large amount of water needs to be introduced in the initial phase in order to dilute the acid residues quickly to below 20% and to cool the acid water mixture.

1.6.6

INCOMPATIBLE CHEMICALS Reaction characteristics Certain groups of chemicals react with those of other groups if they come in contact w ith each other. Such reactions can be hazardous and result in the generation of toxic gases, heat, fire and explosion. A violent reaction can lead to an overflow and the possible rupture of a cargo tank. JBC Code requirements The IBC Code specifies that cargoes, residues of cargoes or mixtures containing cargoes, which react in a hazardous manner with other cargoes, residues or mixtures, must: 1. Be segregated from such other cargoes by means of a cofferdam, void space, cargo pumproom, other pumproom, empty tank, or tank containing a mutually compatible ea rgo; 2. Have separate pumping and piping systems which must not pass through other cargo tanks containing such cargoes, unless encased in a tunnel; and 3. Have separate tank venting systems.

35

The USCG Compatibility Chart Several authoritative bodies have divided chemical cargoes into groups, defining c1riteria for incompatibility between them, and have published lists of i ncompatible cargoes. The most familiar is published by the United States Coast Guard (USCG) (CFR 46 part 150). According to USCG, a mixture of two chemicals is considered hazardous (and the chemicals in question declared incompatible) when, under specified test conditions, the temperature rise of the mixture exceeds 2s•c or a gas is produced as a result of the reaction. Whether cargoes within a pair of groups are i ncompatible is indicated in a table kn own as the USCG Compatibility Chart. The USCG Compatibility Chart assigns each bulk chemical cargo to one of 22 Reactive Groups and 14 Cargo Groups. Reactive Groups contain those chemicals which are the most reactive, so that dangerous reactions can be identified between members of different Reactive Groups and between members of Reactive Groups and Cargo Groups. Chemicals assigned to Cargo Groups are much less reactive and do not react dangerously together. Two incompatible cargoes are not allowed to be stowed adjacent to each other. Caution must be exercised regarding overlapping tanks.

While the USCG table gives general indications, the footnotes and data sheets for any two particular cargoes should always be consulted because there are exceptions to the Compatibility Chart.

<'.

>

Acceptable stowage for Stowage NOT acceptable for Acceptable stowage for non-compatible cargoes non-compatible cargoes, n on-compatible cargoes, due to cofferdam because bulkheads between because bulkheads are shared Tank 2 Starboard and Tank 3 Port are not shared* •stowage of non-compatible cargo is acceptable when tank comers are fonmed of a 'cructfonm Joint' acceptable to t he nag administration as providing double barl!'ler separat ion. Figure 1.2 - Cargo Compatibility

36

TANKER SAFETY GUIDE (CHEMiCAL5)

1.6.7

REACTION WITH CONSTRUCTION MATERIALS The materials used in construction of the cargo systems must be compatible with the cargo to be carried. In addition, care m ust be taken to ensure that no incompatible materials are used duri ng maintenance. Incompatible materials may trigger a self-reaction within the cargo that can be dangerous to ship and crew, o r may cause cargo contamination. Although chemical tankers are designed to contain cargoes safely withi n the cargo system there are occasions when small amounts of a product, such as cargo samples, are required to be stored outside the containment system, within the cargo area. The IBC Code specifies requirements for the safe storage of cargo samples.

1.7

CORROSIVE SUBSTANCES

1.Zl

GENERAL Corrosive substances Corrosive substances destroy human tissue on contact (e.g. skin, eyes and mucous membranes in the mouth and the respiratory tract). They can also corrode metal or other materials used i n ship construction at a very high rate. Some corrosive substances have an anaesth etic effect on the skin so that the harmful effects of exposure are only felt at a later stage. The most common corrosive liquids are acids and al kalis, which can be organic or inorganic in origin. The most dangerous corrosive products can cause severe burns after only a very short exposure time. Some substances become more corrosive in the presence of water, or produce corrosive vapour when in contact with moist air. Alkalis and acids if mixed can form a violent reaction. These two cargo types should be kept totally separated from each other and not be stowed in adjacent tanks. Acids The most corrosive acids are nitric acid, sulphuric acid, chlorosulphonic acid and chloropropionic acid. Formic acid and acetic acid are also highly corrosive in concentrations above 90%. Some acids are known as fuming acids as they produce corrosive acidic vapours. A few acid cargoes are flammable but the non-flammable acids can react with metals to produce hydrogen and can also create a flammable atmosphere. Specific acid ch aracteristics: Nitric acid is a powerful oxidising agent and can cause fire when in contact with combustible materials such as wood and cotton. Fabric materials should therefore never be used on spilled nitric acid or any other oxidising agent; Sulphuric acid and chlorosulphonic acid react violently with water, the resulting reaction producing large amounts of heat which can cause the water to boil; Chlorosulphonic acid, dichloropropionic acid, hydrochloric acid and oleum are toxic by i nhalation; Chloroacetic acid is toxic by ingestion; and Acetic acid and acetic anhydride are flammable. Most other acids are themselves non-flammable but, in general, acids react with metals to evolve hydrogen which is highly flammable. Some acids have a relatively high freezing poi nt and need to be h eated for sea transport to prevent solidification. Examples are acetic acid, oleum (whose freezi ng point varies with its concentration) and super-phosphoric acid.

37

Alkalis Common i norganic alkalis such as potassium hydroxide and sodium hydroxide (caustic) are corrosive to al uminium, zinc and galvanised steel, so these materials should n ot be used within the cargo containmen t system. Other corrosive alkalis include aliphatic and alicyclic amines, pyridines, sodium sulphide solutions and ammonium sulphide solu tions.

1.Z2

IBC CODE REQUIREMENTS The IBC Code requi res secure containment of corrosive cargoes w ithi n a cargo system constructed of suitable corrosion resistant material. Acids must not be carried in tanks where any boundary is formed by the ship's sh ell plating. Because other parts of the ship's structure may come into contact w ith a corrosive cargo as a result of a leak, arrangements m ust exist to detect a leak into spaces adjacent to the cargo system .

1.8

HAZARDOUS CARGO INFORMATION

1.8.1

MATERIAL SAFETY DATA SHEET SOLAS requi res that a Material Safety Data Sheet • (MSOS) must be provided to the vessel for each MARPOL Annex I cargo to be loaded. There is not a corresponding SOLAS requirement for MARPOL Annex II cargoes. Nevertheless, the IBC Code requires that: 'Information shall be on board, and available to all concerned, giving the necessary data for the safe carriage of the cargo in bulk'. In effect therefore the !BC Code requires that an MSDS is provided by the shipper to the ship before loading for each MARPOL Annex II cargo. The Master should ensure that, as far as practical and as part of the ship/sh ore exchange, a copy of the 'data for the safe carriage of the cargo in bulk ' provided to the ship is provided to the cargo receiver (terminal or transhipment ship/barge) so that risk co ntrol measures taken during loading, carriage and unloading are based on accurate information.

It is important that: An MSDS is provided for each cargo; The IBC Code product name, ship type and pollution category are provided; and Other required information on properties and emergency measures is provided i n specific sections of the MSDS.

1.8.2

CONTENTS OF A MATERIAL SAFETY DATA SHEET An example of a suitable M SDS template is i ncluded i n Appendix 5.

It is recommended that the information in an M SDS should be presented i n 16 sections and in the order sh ow n below : Section 1:

Identification - Includes the product or the mixture name or ident ity (GHS iden tifier). To include the manufacturer or distributor's trade name, address, phone number; emergency phone number; recommended u se and restrictions on use as it appears in the IBC Code or most recent edition of MEPC.2/ Circular. If the GHS identifier is different from the IBC Code product name or from the latest edition of MEPC.2/Circular, then this product name should be stated in Section 14 of the M SDS.

Section 2:

Hazard(s) identification - Includes all hazards associated with the product.

Section 3:

Composition/information on ingredients - Includes i nformation on chemical ingredients, water content, any inhibitors and denaturing agen ts which may be present.

The term Material Safety Data Sheet (MSOS) is syncnymous wrth Safety Oat.a Sheel (SOS).

38

TANKER SAFETY GUIDE (CHEM,CALS)

Section 4:

First aid measures - Includes important symptoms and effects, acute or delayed symptoms with recommended or required treatment.

Section 5:

Fire-fighting measures - Lists suitable extinguishing media and techniques, equipment, and specific chemical hazards arising from fire.

Section 6:

Accidental release measures - Lists emergency procedures, protective equipment, and proper methods of containment and clean up.

Section 7:

Handling and storage - l ists precautions for safe handling and storage of cargoes, including incompatibilities with other cargoes/products (e.g. by reference to the use of the USCG Compatibility Chart).

Section 8:

Exposure controls/personal protection - Lists Threshold Limit Values (TlVs), means of vapour detection, appropriate controls, and Personal Protective Equipment (PPE).

Section 9:

Physical and chemical properties - Lists the physical and chemical characteristics of the substance including viscosity and boiling point where appropriate.

Section 10: Stability and reactivity - Lists chemical stability and possibility of hazardous reactions. Section 11: Toxicological information - Includes routes of exposure, related symptoms, acute and chronic effects, and numerical measures of toxicity. Section 12: Ecological information - Includes ecotoxicity, persistence and degradability, bioaccumulation potential, and mobility in soil. Section 13: Disposal considerations - Description of wastes and information on their safe handling and methods of disposal. It should be noted that Annex II of MARPOL 73/78 regulates discharge of residues of chemical liquids transported in bulk. Section 14: Transport information - Hazardous Materials or Dangerous Goods shipping information: • MARPOL Annex I or Annex II carriage requirements with reference to IBC Code and Tripartite agreement as appropriate; • Ship type carriage requirement - 1, 2 or 3; and • Cargo type - X, Y or Z. Cleaning products that are carried on board the ship that are not carried as cargo may be referenced under: • MEPC.2/C ire - Provisional Categorisation of l iquid Substances; and • The IMDG Code - Transport information includes: UN Number; Proper Shipping Name; Transport Hazard Class; Packing Group; Environmental Hazards. This infonmation covers transport of packaged goods (e.g. drums, boxes, containers and portable tanks). Section 15: Regulatory information - Safety, health and environmental regulations specific to the product. Section 16: Other informati on - Includes the date of preparation or last revision.

If sufficient information necessary for the safe transportation of the cargo is not available, the cargo must be refused.

1.8.3

INHIBITED CARGOES For those cargoes required to be inhibit ed during the voyage an inhibitor certificate must be provided. The IBC Code requires that the cargo must be refused if an inhibitor certificate is not supplied. An example of an appropriate inhibited cargo certificate is included at Appendix 6.

39

40

TANKER SAFETY GUIDE (CHEMiCAL5)

CHAPTER2 GENERAL PRECAUTIONS

2

GENERAL PRECAUTIONS

This chapter deals with general precautions which should be observed on a chemical tanker, irrespective of the cargoes being carried.

42

2.1

Introduction

2.2

Moorings

2.3

Emergency Towing-off Pennants (Firewires)

2.4 2.4.1

Access to the Ship Means of access (gangways or accommodation ladders)

2.4.2 2.4.3 2.4.4

Lighting Unauthorised persons Persons smoking or intoxicated

2.5 2.5.1 2.5.2

Warning Notices Permanent Temporary

2.6 2.6.1 2.6.2

Effects of Other Ships and Berths Other tankers at adjacent berths Chemical carrier operations at general cargo berths

2.7 2.7.1 2.7.2 2.7.3 2.7.4

Weather Precautions Wind conditions Electrical storms Cold weather Openings to the accommodation

2.8 2.8.1 2.8.2 2.8.3

Mach inery Spaces Funnel sources of ignition Blowing boiler tubes Cargo vapour

TANKER SAFETY GUIDE (CHEM,CALS)

2.9 2.9.1 2.9.2

Pressure Surges Introduction Generation of pressure surge

2.10 2.10.1 2.10.2

Cargo pumprooms Enclosed spaces

2.11

Ship's Readiness to Move

2.12

Helicopter Operations

2.13 2.13.1 2.13.2 2.13.3 2.13.4

Communication Equipment Ship's radio transmission equipment Electrical maintenance and repairs Transmitting devices Personal electronic items

2.14 2.14.1 2.14.2 2.14.3 2.14.4 2.14.5 2.14.6

Hot Work Assessment of hot work Hot work permit Preparation for hot work Checks by officer responsible for safety during hot work Action on completion of hot work Hot work flow chart

2.15

Cold Work

Pumprooms and Enclosed Spaces

2.16

Mechanically Powered Tools

2.17

Hand Tools

2.1

INTRODUCTION Care and attention should be given to safety precautions at all times, both in port and at sea. As required by the International Management Code for the Safe Operation of Ships and for Pollution Prevention (ISM) Code, 2 the ship's Safety Management System (SMS) should ensure that the concept of 'safety first' is incorporated into the ship's operational and cargo handling procedures. Prior knowledge of a potential problem should allow it to be avoided through precautionary planning or by the development of safe working practices. Ports and terminals may specify the need for additional and different precautions. It is the Master's responsibility to ensure that local regulations are understood and followed.

2.2

MOORINGS Chemical terminals are often located in tidal areas or rivers, with other ships passing at a close distance, thus making proper mooring a significant safety issue. The consequences of a chemical tanker ranging along a jetty or breaking away from a berth could be disastrous, especially during a cargo transfer involving multiple chemicals. Effective mooring is therefore of the utmost importance. Mooring requirements and arrangements are usually determined by the location and the layout of the terminal, supplemented by advice from the pilot, and may differ from port to port. Moorings should be regularly checked and tended to ensure that they remain effective. The Master should ensure that, during cargo operations, sufficient personnel are always available for mooring adjustments.

2.3

EMERGENCY TOWING-OFF PENNANTS (FI REWIRES) Tanker industry experience does not support the use of emergency towing-off pennants (firewires). Some terminals, however, still require the rigging of towing-off pennants fore and aft on the offshore side of the ship. If towing-off pennants are required they should be in good condition, of adequate strength, and properly secured to the bitts such that f ull towing loads can be applied. The eyes should be maintained at or about the waterline in a position that tugs can easily reach . Sufficient slack to allow the tugs to tow effectively should be retained between the bitts and the fairlead, but be prevented from running out by tying off with light rope which will easily break under load . There are various methods currently in use for rigging emergency towing-off pennants, and the arrangement may vary from port to port. A terminal which requires a particular method to be used should advise the ship accordingly.

2.4

ACCESS TO THE SHIP

2.4.1

MEANS OF ACCESS (GANGWAYS OR ACCOMMODATION LADDERS) Personnel should only use the designated means of access between ship and shore, or between ships. When a ship is berthed alongside, at anchor or moored alongside another ship, the means of access should be as close to the living accommodation as possible. The point of access to the deck should be convenient for supervising personnel joining and leaving the vessel, and located as far away from the cargo manifold area as possible. Gangways or other means of access should be properly secured and provided with an effective safety net. Suitable lifesaving equipment such as a lif ebuoy w ith light and line should be available near the access point.

2

for detailed informat>On see 'ICSJISF Guidelines on the Application of the IMO lntemat:oonal Safety Managemet"lt (ISM) Code'.

43

All access to the ship, and control and monitoring of visitors must be in accordance with th e International Ship and Port Facility Security (ISPS) Code and as detailed i n the vessel 's Ship Security Plan.

2.4.2 LIGHTING During darkness the means of access and the surrounding areas must be adequately illuminated .

2.4.3 UNAUTHORISED PERSONS Persons who have no legitimate business on board, or who do not possess the Master's permission to be there, should be refused access. A crew list should be provided to the termi nal security personnel

who, in agreement with the Master. should only allow access to the jetty or berth to people who can demonstrate legitimate business on board the vessel.

2.4.4 PERSONS SMOKING OR INTOXICATED Personnel on watch on board a chemical tanker must ensure that no one who is sm oking approaches or boards the ship. Smoking on board must only be allowed i n the designated smoking areas. Persons under the influence of drugs or alcohol pose a serious threat to safety and should not be permitted on board . The company drug and alcohol policy must be strictly enforced.

2.5

WARNING NOTICES

2.5.1

PERMANENT Permanent notices should be displayed in conspicuous places on board, indicating where smoki ng and use of naked lights are prohibited, and where ventilation is necessary prior to entry.

2.5.2 TEMPORARY On arrival at a terminal, a notice board displaying the following warnings should be posted at the access poi nt to the vessel. The warnings can be translated i nto other languages as. appropriate.

WARNING NO NAKED LIGHTS NO SMOKING NO UNAUTHORISED PERSONS TURN OFF MOBILE PHONES NO USE OF CAMERAS

When toxic or hazardous cargoes are being handled, further notices in appropriate languages should be prominently displayed stating the particular risks of the operations being condu cted. l ocal, national or port regulations may require additional notices to be posted.

44

TANKER SAFETY GUIDE (CHEMiCAL5)

2.6

EFFECTS OF OTHER SHIPS AND BERTHS

2.6.1

OTHER TANKERS AT ADJACENT BERTHS Chemical tankers often berth in close proximity to other tankers and at terminals where many different types of cargo are handled. Even when no cargo operations are being undertaken, dangerous concentrations of cargo vapour may be encountered if cargo or ballast handling, inerting, tank cleaning or gas freeing operations are being conducted by another tanker at an adjacent berth or from operations ashore. Should these operations affect the safety of the vessel then appropriate measures should be taken, and the shore and terminal authorities should be contacted.

2.6.2 CHEMICAL CARRIER OPERATIONS AT GENERAL CARGO BERTHS Where chemical carrier operations are to be conducted at non-designated tanker berths it is unlikely that berth personnel will be familiar with the dangers involved with chemical tanker operations. In particular, they may be unaware of the possible sources of ignition from cranes and other electric equipment or the dangers posed by toxic cargoes. The Master may therefore have to consider requiring the implementation of further precautions in order to ensure the safety of the vessel while alongside. This may involve restricting vehicular access and fencing off the wharf with removable barriers. Additional fire-fighting and response equipment may need to be arranged, with a review evaluating all possible sources of ignition and measures required to make them safe.

2.7

WEATHER PRECAUTIONS

2.Z1

WIND CONDITIONS Many chemical vapours are heavier than air, so cargo vapours released during loading, gas freeing or accidental spills may concentrate in lower areas on deck, with the risk of them entering enclosed areas on board including pumprooms, engine rooms and accommodation, especially in conditions with lit tle or no wind. Strong winds may create low pressure on the lee side of deckhouses or other structures, and thereby cause vapour to be carried in that direction and to accumulate. Personnel should be alert to both of these possibilities.

2.Z2

ELECTRICAL STORMS Electrical storms pose a significant risk to the safety of the ship and to the terminal. Information should be sought regarding local weather conditions and when electrical storms are anticipated in the immediate vicinity of the ship. All operations that may produce flammable vapours should be stopped well before the arrival of an electrical storm and not be restarted until after the storm has cleared. Consideration should also be given to disconnecting the ship/shore connection. This may be a standing requirement of some ports or terminals.

2.Z3

COLD WEATHER During cold weather, precautions should be taken to prevent equipment and systems from freezing. For vessels operating in extreme cold weather conditions it is recommended that a 'winterisation plan' is developed. The plan should be implemented in good time prior to entry into an extreme weather area.

45

Special precautions should also be taken regarding the cargo system, including the PN valve system . Particular attention should be given to th e melting point of the products carried i n order to avoid any unexpected solidification. Water in a fire mai n or spray system should be circulated continuously, where possible. Special attention must be paid to emergency showers and eye-wash stations to ensure they continue to function. Water pipes supplying emergency showers, and eye-wash stations on ships operating in extremely cold weather areas, should be i nsulated and provided with h eat tracing to prevent freezing. When developi ng shipboard procedures to protect agai nst the effects of ext reme rnld weather established industry guidance should be consulted.'

2.Z4

OPENINGS TO THE ACCOMMODATION All doors (except when being used for access), portholes and other openings must be kept fully closed during cargo operations. Accommodation doors that have to be kept closed when in port should be marked accordingly.

If there is any possibility of toxic or flammable vapours being drawn i nto the accommodation, nonessential mechanical ventilation of internal compartments should be stopped, and air conditioning units operated on closed cycle or stopped.

2.8

MACHINERY SPACES

2.8.1

FUNNEL SOURCES OF IGNITION Boilers and machi nery should be mai ntained in good condition as a precaution against funnel fires and sparks. Equipment and systems designed to prevent sparks from escaping from the funnel should be subject to regular inspection and kept well maintained. In the event of a funnel fire, or if sparks are emitted from the funnel, cargo operations, tank cleaning and gas freei ng involving flammable products should be stopped immediately. At sea, the vessel's course should be altered to prevent sparks falling onto the cargo area.

2.8.2 BLOWING BOILER TUBES Funnel uptakes and boiler tubes should not be blown in port. At sea they should only be blown in conditions where the soot w ill be blown clear of the tank deck.

2.8.3

CARGO VAPOUR It is essential that flammable or toxic vapours from cargo operations do not find their way i nto the machinery spaces. The IBC Code specifies the requirements for th e positioni ng of access and ventilation openings to machi nery spaces. Conti ngency plans should be prepared for the possibility of an accident or an emergency that could give rise to a situation where toxic or flammable vapours are likely to enter the machinery spaces. Consideration should be given to the possible effect that such vapour entry may have on personnel or the operation of equipment. The plans should ensure that any necessary preventive actions are taken. Such actions will i nclude isolating the source, closing accesses and openings, shutting down mechanical ventilation systems or mai n machinery, or evacuation of the spaces.

3

'6

Aflpropriate references include OCIMF's 'Use of Large Tankers in Seasonal First Year Ice and Severe Sub--Zero ConditJOns'.

TANKER SAFETY GUIDE (CHEMICALS)

2.9

PRESSURE SURGES

2.9.1

INTRODUCTION A pressure surge is generated in a pipeline system when there is any change in the rate of flow of liquid in the line. The surge can be dangerous if the change of flow rate is too rapid. Pressure surges are most likely to be created duri ng cargo transfer as a result of one of the following actions: Closure of an automatic emergency shutdown (ESD) valve; Rapid closure or opening of a manual or power-operated valve; or The sudden starting or stopping of a pump.

If the total pressure generated in the pipeline exceeds the strength of any part of the pipeline there may be a rupture leading to a spillage of product.

2.9.2

GENERATION OF PRESSURE SURGE The pressure at any point in the cargo transfer system, while the liquid is flowing under normal conditions, has three pressure components: Hydrostatic pressure is pressure exerted due to the difference in height or 'head' of a liquid. The greater the difference in height the greater the pressure exerted; The vapour pressure withi n the ullage space of a tank. If the tank is closed this will be the vapour pressure generated by the product, or if the tank is open to the atmosphere the ambient atmospheric pressure; and The pressure generated by the pump, which is highest at the pump outlet but falls steadily with distance along the pipeline due to losses caused by friction. Rapid closure of a valve creates additional pressure, which could be severe. This is due to the sudden conversion of the kinetic energy of the moving liquid into a compressi ng force which raises the pressure of the liquid within the pipeline. The sudden stop in the flow of liquid is propagated back along the pipeline at the speed of sound and as each part of the liquid comes to rest the pressure is increased. This disturbance is known as a pressure surge. The strength of the surge depends on the density of the liquid, the rate of its deceleration and the velocity of sound through it.

Surge pressure can cause serious damage to equipment and pipelines and result in harm to personnel and the environment.

It is essential that, when loading, valves on the vessel are not shut against the shore pump, especially when handling cargoes at a high loading rate. Cargo loading plans should address the need to decrease the rate progressively from a maximum loading rate to an appropriate topping off rate and the correct procedures for stopping cargo at the required ullage. The time taken for cargo valves to shut, including automatic valves, should also be considered in the loading plan. This is in order to avoid the need to close valves i n an emergency which increases the risk of pressure surge in cargo lines. Closing a valve slowly will help to reduce the build up of a pressure surge. In the event that a valve is closed against a shore pump, the danger of creating a pressure surge will exist.

47

2.10 PUMPROOMS AND ENCLOSED SPACES 2.10.1 CARGO PUMPROOMS Cargo pumprooms, due to their location, design and operation, constitute a particular hazard and therefore necessitate special precautions. Cargo pumprooms should be continuously ventilated during all cargo operations. To meet the requirements of th e IBC Code, th ey must be fitted with mechanical ventilation systems controlled from outside. Because of the potential for the presence of cargo vapours, such spaces should be ventilated for at least 15 minutes before entering and then only after the space has been found safe to enter. Only authorised personnel should enter and operate equipment i n cargo pumprooms. l eakage of toxic liquids and vapours should always be suspected. This is because cargo pumprooms, due to th e complex nat ure of their design, contai n a large number of flanges, valve glands, pumps and couplings. As pumprooms are enclosed spaces, the resulting concentration of toxic and flammable vapours may rise to dangerous levels. The pumproom atmosphere must always be tested for flammable and toxic vapours appropriate to cargoes recently handled, and the pumproom should only be entered if found safe. If entry becomes essential before a safe atmosphere is established this should be considered as a non-routine operation, with shore approval and full enclosed space entry procedures being followed (see Chapter 9). l eaking product should not be allowed to accumulate i n pumproom bilges. If allowed to collect there is a possibility that unsuspected vapours from former cargoes will be released when the surface of the water in the bilge is disturbed. This is especially dangerous where the chemical i nvolved is immiscible with water (cannot form a mix or blend) and heavier than water. Pumproom bilges should be kept clean at all times and a record maintained of the cargoes handled so that incompatible cargoes are kept separated . This is especially i mportant where contaminated bilge water is transferred to a slop tank. Some cargoes are not allowed to be carried in tanks served by conventional below deck pumprooms.

2.10.2 ENCLOSED SPACES Enclosed spaces may contain flammable or toxic vapours or be oxygen deficient. They must not be entered without a permit. Procedures for entering such spaces must be established and strictly followed. Detailed guidance concerning enclosed spaces can be found in Chapter 9.

2.11

SHIP'S READINESS TO MOVE During discharge, loading and ballasti ng operations, alongside a berth or at an anchorage, the ship should be ready for immediate departure in the event of an emergency. Th e ship's boilers, mai n engines, steering machi nery, moori ng equipment and other equipment essential for manoeuvri ng should be kept i n a state of readiness that will permit the ship to move away from the berth or anchorage at short notice. Repai rs and other work which may immobilise the ship should not be undertaken at a berth without prior written agreement from the terminal. It may also be n ecessary to obtain permission from the local port authority before carrying out such work alongside.

2.12 HELICOPTER OPERATIONS Helicopter operations in connection with chemical carriers are not routine operations, but in some ports it has become established practice to embark and disembark the pilot by helicopter. Helicopter operations must not be permitted over the cargo tank deck unless all other operations have been suspended and all cargo tank openings closed. Whenever helicopter services are used the safety measures recommended in the latest edition of the 'ICS Guide to Helicopter/Ship Operations' should be followed.

48

TANKER SAFETY GUIDE (CHEMiCALSJ

2.13

COMMUNICATION EQUIPMENT

2.13.1

SHIP'S RADIO TRANSMISSION EQUIPMENT During medium and high frequency radio transmissions significant energy is radiated, which can create a danger of incendive sparki ng by inducing an electrical potential in unearthed steelwork. The use of medium or high frequency main radio transmission equipment should therefore be prohibited in port and during ship to ship cargo transfers, or at other times when significant cargo vapours may be present such as during tank cleaning at sea. If it is necessary to operate the ship's radio in port for maintenance, the agreement of the terminal and port authorities should be sought. Where possible, in port, all VHF equipment should be used on low power. Low energy transmissions of one watt or less, for example VHF/UHF radios or satellite equipment, are not considered a hazard. However, the repositioning of satellite aerials may i nvolve the running of non-approved drive motors withi n a shore hazardous zone, and consultation between the tanker and the terminal is advisable before the satellite terminal is operated.

2.13.2 ELECTRICAL MAINTENANCE AND REPAIRS Certified safe equipment should be carefully maintained by qualified personnel. Advice from the manufacturer should be sought in case of doubt. Equipment and installations, including radio and satellit e communication equipment, should be regularly inspected and tested. Electric light fittings are often designed to operate only within an agreed temperature range depending on the groups of cargoes that the vessel is permitted to carry. It is important therefore that the maximum power of the lighting element is not exceeded. Care must be taken to replace a defective lamp with one of the same power rating. Fitting a higher power lamp than the original can alter the temperature group of the fitting with consequent restrictions on the cargoes that the ship may carry safely. When equipment in a gas dangerous area is disconnected for servici ng, the associated wiring and conductors should be correctly terminated or adequately insulated. If it is necessary for the purpose of repairs or alterations to use soldering apparatus or other means involving heat or flame, including the application of a voltage to apparatus for testing purposes, then a hot work permit must be obtai ned. Detailed guidance concerning hot work can be found in Section 2.14.

2.13.3 TRANSMITTING DEVICES Personal equipment such as mobile telephones, if switched on, presents a hazard when the calling mechanism is activated. This is aggravated with mobile phones due to the natural tendency to answer a call irrespective of the immediate environment. In view of the widespread use of such equipment, appropriate control procedures should be followed to prevent their use within th e cargo area. Visitors should be informed that such items must not be taken into the cargo area or other unsafe areas, even if switched off, and should only be switched on withi n the vessel's safe areas. All hand held radios used on board, whether for cargo work or other purposes, should be safe for use in a hazardous area.

Procedures should require that no mobile phones or similar transmitting devices are carried by personnel, including visitors, when working within the cargo area.

49

2.13.4 PERSONAL ELECTRONIC ITEMS Small battery powered personal items such as watches are not significant ignition sources when correctly used. However, portable domestic radios, electronic calculators, cameras and other nonapproved battery powered equipment must not be used within the cargo area or wherever flammable vapours may be encountered. When in port, local regulations may prohibit the use of any portable electrical equipment.

2.14 HOT WORK 2.14.1 GENERAL All ship operators should have procedures describing how hot work can safely be carried out on board which should form part of the SMS required by the ISM Code. Hot work means any work requiring the use of electric arc o r gas welding equipment, cutting burner equipment or other forms of naked flame, as well as spark generating tools. It covers all such work, regardless of where it is carried out on board the vessel, including open decks, machinery rooms and the engine room. Repair work outside the main engine room which necessitates hot work should only be undertaken when it is essential for the safety o r immediate operation of the vessel, and when no alternative repair procedure is possible. Hot work outside the engine room (and in the engine room when associated w ith fuel o r lubrication systems) should be prohibited until the requirements of applicable regulations have been met, safety considerations taken into account, a risk assessment has been carried out, and a hot work permit has been issued. This should involve the agreement of the company, Master, superintendent, the shore contractor, the terminal representative and the port authority as appropriate. Hot work in port at a chemical terminal is normally prohibited. If such work becomes essential for safety or urgent operational needs, then the ship must comply with port and terminal regulations. Full liaison should be established with port and terminal authorities before any work is started.

2.14.2 ASSESSMENT OF HOT WORK The Master is responsible for deciding whether hot work is justified, w hether it can be conducted safely and for complying w ith the company's hot work procedure. Hot work in areas o utside the engine room should not be commenced until clear procedures have been discussed and agreed. The Master should provide consent to the planned hot work in w riting. Before hot work commences, the Master should hold a safety meeting, at which the planned work and the safety precautions are carefully reviewed . The meeting should be attended by all those who w ill have responsibilities in connection with the work. An agreed written plan for the work and the related safety precautions should be prepared. The plan must identify the officer who is to be responsible for the supervision of the work, and another officer who is responsible for implementing safety precautions and communications between all parties involved. All personnel involved in the preparations and in the hot work operation must be briefed and instructed in their respective roles. They must clearly understand which officer is responsible for work supervision and which for safety precautions.

Any hot work to be undertaken on board outside the engine room workshop should be subject to a risk assessment and require a hot work permit.

SO

TANKER SAFETY GUIDE (CHEM,CALS)

2.14.3 HOT WORK PERMIT A hot work permit is issued under the authority of the Master and ensures that those involved in hot work are aware of the hazards associated with the planned work and that they implement safety measures to mitigate the hazards. The hot work permit also provides a checklist for hot work fire safety and serves as a reminder before, during, and after any hot work is conducted. The permit should specif y the duration of validity, which should not exceed one working day. An example of a hot work permit is provided in Appendix 2.

2.14.4 PREPARATION FOR HOT WORK No hot work should be undertaken inside an enclosed space until it has been cleaned as necessary and ventilated. Tests of the atmosphere in the compartment should indicate 21 % oxygen content by volume, flammable vapour as low as possible but not more than 1% lfl, and that the space is free of toxic gases. Adjacent compartments should either be cleaned and gas freed to hot work standard or freed of cargo vapour to not more than 1% lfl and kept inerted, or completely filled with water. No hot work should be undertaken in a compartment beneath a deck tank containing cargo. Care should be taken to ensure that no release of flammable vapour or liquid can occur from nonadjacent compartments that are not gas free. No hot work should be undertaken w ithin 30 metres of a tank containing flammable cargo. No hot work should be undertaken on the open deck unless the area is free from flammable vapour and all com partments, including deck tanks, within 30 metres of the work location have been tested and confirmed to be non-flammable. The company's SMS' should give guidance on required hot work procedures and it should be noted that local or national regulations may provide further guidance. It is important to continue ventilation w ithin the space during all hot work operations. All sludge, cargo-impregnated scale, sediment or other material likely to give off flammable or toxic vapour, especially when heated, should be removed from the area. All combustible material such as insulation should either be removed or protected from heat. An adjacent fuel oil bunker tank may be considered safe if tests of the tank's atmosphere give a reading of not more than 1% lfl in the ullage space of the bunker tank, and no heat transfer through the bulkhead of the bunker tank will be caused by the hot work. Hot work must not be carried out on the bulkheads of bunker tanks that are in use. All pipelines interconnecting with cargo spaces should be flushed, drained, vented and isolated from the compartment or deck area where hot work is to take place. Hot work on pipelines and valves should only be permitted when the section of line needing repair has been removed from the cargo system by cold work and the remaining system blanked off. The removed section of line should be cleaned and gas freed to a standard that is safe for hot work, regardless of whether or not it is removed from the hazardous cargo area. All other operations utilising the cargo or ballast system should cease before hot work is undertaken, and remain so throughout the duration of the hot work. If hot work is interrupted for any reason for an extended period, hot work should not be resumed until all the precautions have been rechecked and a new hot work permit has been issued.

4

for detailed informabOn see 'ICSJISF Guidelines on the Application of the IMO lntemabOnal Safety Management Code'.

51

2.14.5 CHECKS BY OFFICER RESPONSIBLE FOR SAFETY DURING HOT WORK Im mediately before hot work is started, the officer responsible for safety precautions should examine the area where it is to be undertaken, and ensure that tests of the working area and adjacent spaces show n ot more than 1% Lfl. If the work is i nside an enclosed space, the responsible officer must also check that the oxygen content is 21 % by vol ume and that the space is free of toxic gases. Adequate fire-fighting equipmen t must be laid out and be ready for immediate use. Fire w atch procedures must be established in the area of the hot work and in adjacen t, non-inerted spaces where the transfer of heat could create a hazard. Effective means of containing and extinguishing welding sparks and molten slag must be established. The work area must be adequately and co ntinuously ventilated . Flammable solvents must n ot be present, even for use in cleaning tools. The frequency with which the atmosphere is to be monitored must be established. Atmospheres sh ould be retested at regular intervals and after each break in work, such as for refreshments or meals. Checks should be made for flammable vapours or liquids, toxic gases o r i nert gas from nongas free spaces. Welding apparatus and other equipment to be used should be carefully inspected before use to ensure that it is in good condition and, where required, correctly earthed. The follow ing should be complied with whenever electric arc welding equipment is used: Electrical supply connections are made withi n a gas free space; Existi ng w i ring, including supply wiring, is sufficient to meet the pow er demands of the welding equipment w ithout overloading th e cables which would cause a risk of overheating; Flexible electric cables laid across the deck have effective insulation; and Power cables to the work site follow the safest possible route, only passi ng over gas free or inerted spaces.

2.14.6 ACTION ON COMPLETION OF HOT WORK On completion of hot work, the work area should be secured, and all hot work and related equipment u sed should be removed. The company should be informed of the completion of all hot work as specified in the hot w ork permit.

52

TANKER SAFETY GUIDE (CHEMICALS)

2.14.7 HOT WORK FLOW CHART The following flowchart assumes that the work is considered essential for safety or the immediate operational capability of the ship, and that it cannot be deferred until the next planned visit to a repair yard. can the task be achieved

--.r-., without using hot wortc? Is the part of the ship Nqulrlng

wortc a pipeline or other fitting

FITIING

or Is It a permanent structure?

PERMANENT STRUCTURE

can the fitting .,. disconnected and removed from hazardous cargo area before hot wortc?

Description of wortc M
consent or altemadve plans to be considered.

Mast•r to hold saf•ty !Meting on board - - by all having .-----..~--. responslbllltlM during wortc

Is satisfied that wortc can be completed safely?

--.-Hot work permit

to.,.

period of valldlty

Completeal _ _..

Written statement of work to be drawn up showing separate

for hot work

responslbllltlM for wortc supervision and safety

Stopal-lnhazardousargo-

Figure 2.1 - Hot Work Flow Chart

53

2.15 COLD WORK No specific 'cold work permit' is required. However, when work is carried out the requirements of a permit to work system should be followed. Work should not be carried out on any apparatus or wiring, nor should any flame proof or explosion proof endosure be opened, nor the special safety characteristics provided in connection with standard apparatus be impaired, until all power has been cut off from the apparatus or wiring concerned. The power should not be restored until work has been completed and the above safety measures have been fully reinstated. Any such work, including changing of lamps, should only be done by an authorised person. Cold work refers to work with tools that may expose the user to hazardous situations such as: Working on electrical equipment within a hazardous environment. This should only be done when electrical power has been cut off and tagged; Openi ng up of pipelines and cargo equipment which may expose personnel to trapped toxic or flammable products; and Chippi ng and scaling of the ship's structure which may cause contact sparking. Whenever cold work is planned within the cargo area or other hazardous areas, a permit to work should be issued for each intended task. The permit should specify the duration of validity, which should not exceed one working day. The atmosphere within any enclosed space i n which hot or cold work is to take place should be tested for hydrocarbons and a reading of less that 1% LFL obtained on suitable monitoring equipment.

2.16 MECHANICALLY POWERED TOOLS Although grit blasting and the use of mechanically powered tools are not normally considered to fall within the definition of hot work, these operations should only be permitted under controlled conditions. Unless the company has a detailed procedure covering the use of power tools, a risk assessment should be carried out prior to permitting their use within the cargo or other hazardous area. The work area should not be subject to vapour release or a concentration of combustible vapours, and should be free from combustible material. The surrounding area should be tested and the atmosph ere confirmed to be below 1% LFL. The ship must not be alongside at a terminal. There must be no cargo, bunkering, ballasting, tank cleaning or gas freeing operations in progress. The hopper and hose nozzle of a grit blasting machine should be electrically earthed to the deck or the fitting to be treated. There is a risk of damaging pipelines when grit blasting or chipping, and great care m ust be taken when planning such work. Cargo and inert gas pipelines should not be blasted or mechanically chipped unless the entire vessel is gas free. Adequate fire-fighting equipment should be laid out and be ready for immediate use.

2.17 HAND TOOLS The use of hand tools such as chippi ng hammers and scrapers for steel preparation and maintenance may be permitted without a permit to work. Their use should be restricted to deck areas and fittings not connected to the cargo system. The work area should not be subject to vapour release or a concentration of com bustible vapours. The area should be gas free and clear of combustible materials. There must be no cargo, bunkering, ballasting, tank cleaning or gas freeing operations i n progress.

Work with hand tools on cargo pipelines and inert gas pipelines should be subject to the same precautions as applicable to the use of power tools.

54

TANKER SAFETY GUIDE (CHEMiCAL5)

CHAPTER 3

SAFETY MANAGEMENT, TRAINING AND PPE

3

SAFETY MANAGEMENT, TRAINING AND PPE

This chapter describes the responsibilities of the company to ensure that an effective Safety Management System is in place for the safe operation of the ship. Manning, crew familiarisation and training requirements are explained. Detailed risk assessment advice is provided and the important definitions of routine and non-routine operations are described in detail. Guidance is also provided on Personal Protective Equipment (PPE).

3.1

Introduction

3.2 3.2.1 3.2.2

Implementing a Safety Culture What is a safety culture? Key features of an effective safety culture

3.3

The ISM Code

3.4

Company Responsibility

3.5

Safety Information for Shore Personnel

3.6

Outside Contractors

3.7 3.7.1 3.7.2 3.7.3

Risk Management Risk assessment terms Conducting risk assessments Risk assessment matrix

3.8 3.8.1 3.8.2

Safe Operations Routine operations Non-routine operations

3.9

Incident Investigations

3.10 3.1 0.1 3.1 0.2 3.1 0.3 3.1 0.4 3.1 0.S 3.1 0.6 3.1 0.7 3.1 0.8

Ship's Manning Responsibility Familiarisation Tanker specific training requirements Basic tanker training Advanced tanker training Crew communication Drills and exercises Crew schedules and minimum hours of rest Summary of STCW requirements - hours of work and rest Prevention of drug and alcohol abuse

3.1 0.9 3.1 0.10

56

TANKER SAFETY GUIDE (CHEMICALS)

3.11 3.1 1.1 3.1 1.2 3.1 1.3 3.1 1.4 3.1 1.S

3.1 1.6 3.1 1.7 3.1 1.8 3.1 1.9 3.1 1.10 3.1 1.1 1 3.1 1.12 3.1 1.13 3.1 1.1 4 3.1 1.15 3.1 1.16 3.1 1.17

Personal Protective Equipment (PPE) Atmosphere monitoring equipment Safe working clothing Protective clothing Toxic or corrosive substance protection Chemical resistant clothing (protective suits) Types of chemical resistant clothing Eye protection Hand protection Foot protection PPE matrix Respiratory protectiono Canister or filter type respirators Self-Contained Breathing Apparatus (SCBA) Air line breathing system Emergency escape respiratory protection Maintenance Training

3.1

INTRODUCTION The operation of chemical tankers is specialised and complex and is governed by comprehensive international Conventions and Codes, most of which have been developed by IMO. Regulation of the technical aspects of chemical tanker operations can only achieve part of the objective of safe and pollution free operations. While the Master is clearly responsible for the safety of the ship and its crf!N, the overall responsibility for safe operations rests with the owner, or the entity that has assumed responsibility for the ship's operation in accordance with the ISM Code. It is commonly asserted that around 80% of all shippi ng accidents are caused by human error. In reality, however, an act or omission by a human being plays some part in virtually every acciden t. A failure to follow procedures is a clear example of an act or omission that regularly plays a part in accidents. Any decision or action taken on board or ashore needs to be based on a sound understanding of its consequences. The task facing shipping company managers is to minimise the scope for poor human decisions which may contribute, directly or indirectly, to maritime casualties, personal injuries or pollution incidents.

3.2

IMPLEMENTING A SAFETY CULTURE

3.2.1

WHAT IS A SAFETY CULTURE? It is important for everyone in th e company, ashore and afloat, to have an understanding and appreciation of the concept of safety culture. For a Safety Management System (SMS) to be truly effective, the Company must encourage and motivate its personnel to make safety and environmental awareness thei r highest priorities. While the International Management Code for the Safe Operation of Ships and for Pollution Prevention (ISM) Code states that one of its key objectives is to establish a safety culture in shipping com panies, it does not actually define the meaning of the term. However, a safety culture may be described as the values and practices that management and personnel share to ensure that risks are always minimised and mitigated against to the greatest degree possible. In other words, with an effective safety culture, safety and pollution prevention are always the high est priority. The company and its staff will always, and automatically, think about th e implications for safety of every action, rather than simply follovving safety procedures because they have been imposed from outside. In an effective safety culture, everyone employed by the company, whether a manager, Master or a junior rating, truly believes in and understands the purpose of establish ed procedures, and will think about safety, and the means of i mprovi ng it, as a matter of course. A safety culture will also h elp to eradicate any tendency towards behavioural complacency, when the n eed to adhere strictly to safety and pollution prevention procedures migh t be inadvertently overlooked, either on shore or at sea, because of the misconception that if a particular type of accident has never previously happened it may never occur. Analysis of serious accidents in shippi ng has demonstrated that the personnel involved are often highly trai ned, competent and experienced, and that th e underlying cause of the accident, which could have been prevented, was a failure to follow established procedures. The key to maintai ning a safety culture is for all concerned to recognise that it is a matter of enlightened self-interest. The crew will be less likely to be the victims of accidents, and the company can use it as a means of maximising the financial benefit and cost savings that may be derived from implementing the ISM Code. It is important that companies recognise that investment in safety produces financial savi ngs and is thus not a 'cost'.

57

3.2.2

KEY FEATURES OF AN EFFECTIVE SAFETY CULTURE The key features of an effective safety culture are as follows: 1.

Recognition that all accidents are preventable and only usually occur following unsafe actions or a failure to follow established procedures.

2.

Management and personnel should think constantly of safety. An effective safety culture will support a shipboard environment that encourages and requires all on board to proactively consider their own and others' safety. In this way individual seafarers assume responsibility for safety rather than relying on others to provide it. Through mutual respect, increasing confidence in the value of the safety culture results in a more effective SMS.

3. Always setting targets for continuous improvement, with a goal of zero accidents and ISM Code non-conformities. There are perhaps three key components to developing an effective safety culture: Commitment from the top; Measuring current performance and behaviour; and Modifying behaviour.

3.3

THE ISM CODE The ISM Code requires ship operating companies to develop and implement a Safety Management Sys1em (SMS) to ensure safe working conditions for all personnel and to minimise the risk of damage to the environment by company operations. A properly functioning SMS should ensure that: All personnel, both on board and ashore. are motivated fully to implement company policies and procedures and contribute to the process of continuous improvement; Audits, both internal and external, and other control processes are implemented to measure the effectiveness of the SMS; and Feedback from operational experience is used to further improve the company's SMS. The nature of cargoes handled by chemical carriers obviously requires that the company's SMS is developed to take into account the risks involved in handling dangerous cargoes.

3.4

COMPANY RESPONSIBILITY To be effective. an SMS needs to be much more than just documents containing procedures and checklists. The company should define the company's values and aspirations and detail how it intends to achieve its stated policies. Management must also provide adequate resources to ensure that vessels are properly managed, crewed, operated and maintained by well trained and competent personnel. In an effective SMS: Incidents and near misses are investigated to determine the root causes; Incidents and accidents are thoroughly investigated and the findings analysed and corrective actions implemented to prevent reoccurrence; Operational procedures are regularly reviewed and trends analysed to identify potential risks. Effective measures to minimise the risks identified are incorporated into the SMS; Where possible, measurement techniques are used to identify trends which can indicate where attention needs to be focused before an accident occurs; and There is a sys1em to manage change in working practices associated with the introduction of new equipment or systems.

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3.5

SAFETY INFORMATION FOR SHORE PERSONNEL The Master and crew should be aware that most persons coming on board are not familiar with the hazards of chemical tanker operations o r of th e action to take i n an emergency. Even specialised personnel boarding th e ship for cargo related issues (for instance cargo surveyors) may not be familiar with other products that are being handled at the same time. It is therefore essential that all persons, including contractors and sub-contractors boarding the ship, are provided with an overview of th e hazards present and the safety precautions to observe while they are on board. This advice should include: Products being handled whilst they are on board; Details of restricted and permitted areas; What to do if the emergency alarm sounds; What to do and where to go if contamination with chemicals occurs; and What to do if involved in an accident on board. It is recommended that the advice is presented in written format and handed to each visitor on boarding the ship. An example of such an instruction card can be found in Appendix 1. It is also recommended that similar advice is provided to those persons who are worki ng close to the vessel, for example the crews of barges (bunkers, stores) and to personnel worki ng close to the ship's side. This is especially relevant if cargo operations or gas freeing operations are taki ng place which can spread cargo vapours over a large area.

3.6

OUTSIDE CONTRACTORS It is com mon practice for contractors and sub-contractors to work on ch emical tankers, particularly duri ng cargo operations and tank cleaning. The SMS should address the employment of outside contractors and should provide guidance to the Master, officers and crew regarding their management and control. Should there be any doubt as to an individual's fitness to work on board they should not be allowed to engage in any work. Contractors and sub-contractors should be made aware of and comply with the ship's safety policies, procedures and work practices i ncluding th e company's enclosed space entry procedures. It should be confirmed that such contractors are aware of the particular risks and dangers associated with th eir work on board and that they are aware of the actions to take in an emergency (see Section 3.5). PPE used by contractors and sub-contractors should be appropriate for the intended work on board the ship.

3.7

RISK MANAGEMENT The ISM Code does not specifically require a company to adopt a formal approach to risk management or a risk based approach to managing safety or environmental protection. However, this is clearly implied by the ISM requirement for the company to 'assess all identifiable risks to its ships, personnel and the environment and establish appropriate safeguards'. It is therefore recommended that the identification of risks or hazards, and putting in place risk reduction measures, should be key features of the ISM Safety Management System. Under some jurisdictions or commercial contracts th e conduct of risk assessments may be a mandatory requirement. However, whether mandatory or not, every company will find the adoption of a risk based approach to safety to be valuable. The intelligent use of assessments, and adopting a risk based approach to managing safety, can also substantially reduce the amount of paperwork required within an SMS.

3.Z1

RISK ASSESSMENT TERMS There is nothing mysterious or particularly complicated about risk assessment. Good seamanship has always meant that seafarers have been actively engaged in the assessment of risks. Nevertheless, some specific terms have grown up around risk assessments with terms being used in a precise and particular way, which is not necessarily how these same words may be used in everyday language. Although not exhaustive, the definitions and explanations shown in the following table may be helpful:

3.Z2

TERM

DEFINITION

HAZARD

A hazard is anything with the potential to cause hanm t o persons, property or the environment, e.g. entering a cargo tank to inspect heating coils.

RISK

A risk is the likelihood, or probability, that a hazard will cause specified harm to someone or something, e.g. the probability of a seafarer becoming asphyxiated in the cargo tank.

RISK MANAGEMENT

Risk management is a process that involves assessing the risks that arise on board, putting health, safety and environmental protection measures in place to control them, and then ensuring they work, such as enclosed space entry procedures and the ability to com ply with the ship's Safety Management System.

RISK ASSESSMENT

A risk assessment is an examination of what, on board, may cause harm to personnel, property or the environment, so that it can be determined whether adequate precautions have been taken.

BARRIERS

The measures or safeguards taken to prevent an incident with the potential for causing harm and to reduce the consequences.

REASONABLY PRACTICABLE

This means that active steps have to be taken to control the health and safety risks on board except where the cost (in tenms of time and effort as well as money) of doing so is 'grossly disproportionate' to the reduction in the risk. However, if a task cannot be carried out safely, i.e. if the hazards cannot be controlled to a very high degree, then that task should not be allowed to proceed.

ALARP

As Low as Reasonably Practicable.

CONDUCTING RISK ASSESSMENTS The reason for conducting risk assessments is to control work proactively, to reduce the probability and consequences of unexpected or unplanned events and to ensure compliance. Risk assessments will, if used correctly by all involved, reduce accidents and consequential losses. There are many broadly similar approaches to risk assessment. The following represents an example: Identify the hazards; Decide who might be harmed and how; Evaluate the risks and decide on precautions; Record findings and implement them; and Review the risk assessment.

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3.Z3

RISK ASSESSMENT MATRIX When evaluating the risk it is quite normal to establish a risk level o r risk factor by categorising the likelihood of harm occurring and the potential severity of harm, and then plotting these two risk determining factors against each other in a risk matrix (see below). The prioritisation of the results is important and the identified risk level can assist in determi ning which risks should be tackled first. However, it is very important to keep risk assessments simple and avoid them becoming over com plicated, for example by tryi ng to i ntroduce too many categories.

Potential severity of harm

likelihood of Harm Occurring

Extreme Harm

HIGH RISK

Very Unlikely

Unlikely

likely

LOW RISK

Very likely

LOW RISK

While it is correct to keep risk assessments simple, it must be realised that a reasonable amount of experience and expertise is necessary to evaluate effectively the likelihood of harm and potential consequences. If the risk assessment is not effective it could result i n unnecessary controls being applied or, worse, failure to identify controls that are needed. When conducting risk assessments it is important to i nvolve those who are actually going to do the job. They will generally be in a good position to identify hazards and can have valuable suggestions on what practical steps should be introduced to control these and reduce risk. Many activities take place on board a chemical tanker when informal, almost subconscious risk assessments take place. Safety conscious seafarers may routinely follow standard operating procedures or comply with safe working practices, but they will still be assessi ng risk. There are occasions, however, when a more formal approach should be taken to risk assessment. A risk matrix should be produced and a record made of the assessment whenever an unusual activity is to take place, or whenever one of the risk factors is known to be particularly high.

3.8

SAFE OPERATIONS

3.8.1

ROUTINE OPERATIONS All routine operations which are required to be carried out on board should be covered by written procedures as part of the company's SMS. These procedures should be based on industry best practice, such as described in this Guide and in other i ndustry publications. In developi ng effective procedures the risks involved i n carrying out routine operations should be fully assessed and safeguards put in place to prevent injury or damage. The procedures should be regularly audited to ensure that they remai n fit for purpose and that they are compliant with regulation. Auditi ng should also check that procedures are implemented on board and are subject to a process of continuous improvement.

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3.8.2

NON-ROUTINE OPERATIONS A non-routine operation is one that is not covered by standard company procedures and therefore the risks involved in carrying out the task have not been comprehensively assessed and addressed. Although some aspects of the operation may be covered by existing procedures, it is important that prior to carrying out a non-routine operation a detailed risk assessment is carried out in order to address all of the identifiable risks and to plan accordingly. A non-routine operation always requires approval from shore management. The evaluation and approval of a non-routine operation should incorporate input from all relevant departments. The approval process should always include input from the department with responsibility for health and safety. Any procedures developed in consultation with shore management should not be used for another similar operation or retained for use as a procedure for any other operation on board, unless it has been formalised and documented into a company approved procedure.

Operation Completed, Recorded and Shore Management Notified

Operations for which supporting company procedures are not available should be considered as non-routine.

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3.9

INCIDENT INVESTIGATIONS Lessons learned from the investigation of accidents and near misses provide valuable input for improving procedures to prevent a reoccurrence. The company's SMS should contain an investigation procedure which should guide the crew and the company in identifying the root causes of an incident and corrective and preventive measures to be applied.

3.10 SHIP'S MANNING An essential requirement of an effective SMS is that all personnel are competent and trained relative to their position within the company. The International Convention for the Safety of Life at Sea (SOLAS) and the International Convention on Standards of Training, Certification and Watchkeeping for Seafarers (STCW) stipulate requirements to ensure that crews are appropriately trained, competent and familiar with their duties and responsibilities on board ships on which they serve. The ILO Maritime Labour Convention (MLC) also addresses a wide range of matters including the obligations of shipping companies with respect to seafarers' contractual arrangements, the responsibilities of manning agencies, working hours, health and safety, crew accommodation, catering standards, and seafarers' welfare.' The STCW Convention is the principal international treaty regulating the training and certification of seafarers. It also regulates watchkeeping arrangements, including seafarers' minimum rest hours.•

3.10.1 RESPONSIBILITY The STCW Convention requires the flag state administration to: Ensure that all seafarers who sail under their flag have been trained and issued with certificates of competency in accordance with the STCW standards. This includes the competence of seafarers whose STCW certificates have been issued by another country; and Specify safe manning levels and ensure compliance with their crewing regulations. The STCW Convention requires inter alia that shipping companies ensure that: Every seafarer assigned to any of its ships holds an appropriate certificate; Its ships are manned in compliance with the applicable safe manning requirements of the flag state; Seafarers assigned to any of its ships have received refresher training as required by the Convention; Documentation of each crew member's experience, training, medical records and competency in assigned duties (including experience of chemical tankers) is maintained; All seafarers, on joining their ship, are made familiar with their specific duties, the layout and equipment of the chemical tanker relative to their position on board and their role in the emergency organisation; All seafarers have received specific training, applicable to their rank on board when sailing on particular vessels i.e. chemical tankers carrying NLS; The crew can carry out their routine tasks safely and with due regard to requirements for the protection of the environment; The ship's crew can effectively coordinate their activities in an emergency situation; and The crew can effectively communicate with each other, which in practice will usually require the use of English.

S 6

The 'ISf Guidelines on the AppicabOn of the ILO Maritime labour COl'\'\'ef'ltion' provide co~rehensive ~idance. The 'ISf Guidelines on the IMO STC\\f Convention and Code including the 2010 Manila Amendments' provide further guidance.

63

3.10.2 FAMILIARISATION Companies are required to ensure that th e crew are familiar with their specific duties and w ith the ship's layout and arrangements, its equipment, SMS procedures and any special vessel characteristics that are relevant to their routi ne or emergency duties. The company's crewing policies and procedures should ensure that all crews are familiar with the shipboard equipment, operating procedures and other arrangements needed for the proper performance of their duties, before being assigned to those duties. Where possible, the company should arrange to forward details of the ship and its intended itinerary to the seafarer prior to joining. On joi ning the ship, an appropriate crew member should be designated to ensure that newly joini ng personnel are shown around the vessel and introduced to their duties and the equipment and systems for which they will be responsible. The following should be considered when developing familiarisation procedures: Ensuri ng that the Master and other senior officers are trained and familiar with the SMS prior to joining the vessel or before assuming their responsibilities; Ensuri ng that the seafarer is familiar with th e ship, its equipment and the SMS; Providing i nstructions that clearly define the crew member's role w ithin the ship's organisation. These instructions should also include the crew member's responsibility, authority and interrelationships with others involved i n the SMS; Providing documentary evidence that the seafarer is fully familiar with their emergency stations and responsibilities, and the relevant material contai ned in the ship's SOLAS traini ng manual; Allowing a period of hand-over between seafarers joi ning and leaving based on the ship's trading pattern, the workload and the seafarers' general and specific experience of the ship and its cargoes; and The use of video and other media training programmes to describe the company's SMS and details of the ship. This has the advantage that elements of such training can be completed prior to joining the ship. The choice and level of detail to assist familiarisation vvill depend on the i ndividual's prior experience and on board responsibilities. The company should identify individuals who, prior to sailing, require particular familiarisation with the ship and its systems, and plan accordingly.

3.10.3 TANKER SPECIFIC TRAINING REQUIREMENTS The STCW Convention contains comprehensive training requirements for oil and chemical tanker operations, at both basic and advanced levels.

3.10.4 BASIC TANKER TRAINING Officers and ratings assigned specific duties and responsibilities related to cargo or cargo equipment on oil or chemical tankers need to hold a certificate in basic trai ning for oil and ch emical tanker cargo operations. Essentially all officers and ratings with any duty related to the carriage of oil or chemicals will have to undertake the relevant basic traini ng as specified in the Competence Tables contained in Chapter V of STCW. To achieve this certificate i n basic training for chemical tankers, seafarers are required to have at least 3 months seagoing service on the relevant type of tanker and meet the standard set out in the relevant STCW Competence Table. Alternatively, a basic training course i n oil or chemicals, as appropriate, which has been approved by the administration, can be undertaken to meet the required standard of competence.

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TANKER SAFETY GUIDE (CHEMICALS)

3.10.5 ADVANCED TANKER TRAINING STCW requires that Masters, chief engineers, chief mates, second engineer officers and any person with 'immediate responsibility' for loading, discharging, care in transit, handling o f cargo, tank cleaning or other cargo-related operations on oil tankers or chemical tankers will have to h old the relevant certificate for tanker cargo operations. The STCW Code contains guidance on the meaning of 'immediate responsibility':

The term "person with immediate responsibility"... means a person being in a decision making capacity with respect to loading, discharging, care in transit, handling of cargo, tank cleaning or other cargorelated operations.

All officers who make decisions relating to loading, discharging, care in transit handling of cargo, tank cleaning or other cargo-related operations should have successfully completed the advanced level of STCW tanker training.

To achieve the advanced STCW certification in tanker operations there are two available options: After having completed approved trai ning meeting the required competence standards (and having met the requirements for basic training) the seafarer will need to gain at least 3 months approved seagoi ng service on the appropriate tanker type; or Recognising th e benefits of structured on board training, seafarers who meet the competence requirements above can reduce the sea time requirement to 1 month, provided that they undertake at least three loading and three unloading operations in that tim e, and that their training is documented in an approved training record book, taking into account th e guidance in Part B of the STCW Code. In practice, it is unlikely that seafarers will complete all the required training within just 1 month of seagoi ng service. However, use of an approved training record book, and the option to reduce sea time, should still permit seafarers to achieve the advanced certification in a shorter amount of time. It could also be considered advantageous for an on board trai ning record book to be utilised even if the option of a 3 month programme is selected, to ensure that properly structured training is undertaken and recorded. The advanced certification will either be in the form of a certificate of proficien cy, or an endorsement to an existing certificate of proficiency or competency. Extensive guidance for tanker training is provided in Part B of the STCW Code.

3.10.6 CREW COMMUNICATION The complexity of chemical tanker operations requires that the officers and crew can communicate effectively. Cargo operations can be complicated and any misunderstandings could jeopardise safety. The company should take measures to ensure that the employment of crews from different nationalities does not impair communication or introduce cultural barriers which can adversely affect on board organisation. To ensure effective crew performance a working language for the ship should be established by the com pany. Each seafarer should be able to understand and give instructions i n the working language on board. Seafarers should be able to understand all plans and procedures posted on board. English is th e most com monly used language at sea. The IMO Standard Marine Communication Phrases (SMCP) have been developed to promote the use of English during an emergency and for routine com munications between ship and shore.

65

3.10.7 DRILLS AND EXERCISES As a minimum, emergency drills and exercises as required under the ISM Code should be held in order to: Improve the crew's ability to handle any emergency situation that could occur on board; Enable the crew to test their ability to work effectively togeth er when operating under stressful conditions; and Provide the opportunity for crew mem bers to perform different roles during drills so that additional experience is gained.

3.10.8 CREW SCHEDULES AND MINIMUM HOURS OF REST The workload on chemical tanker crews, especially i n port, is very demanding and i nvolves round the clock operations loading, discharging and preparing cargo tanks for the next cargo. In major ports the vessel may have to shift or change berth many times and also undertake bunkering, stori ng, crew changes and other operations.

It is therefore essential that the management of the vessel is planned so the crew get the necessary rest i n between periods of duty so their work is not impaired by fatigue. Fatigue has been proven to increase the risk of accidents. Hours of work and rest are regulated by the STCW Convention and the ILO Maritime Labour Convention. The Master should ensure that the requirements of these regulations form the basis of the planning process and that full compliance is achieved. The Master should boe supported by the vessel's management and measures should be taken to ensure that statutory rest requirements are met. Charterers increasingly wish to see evidence of this planning process and work hour records that demonstrate compliance w ith their own policies concerning work hours. Should the workload not allow crew members to get the necessary rest, the Master should stop operations until it is safe to proceed.

3.10.9 SUMMARY OF STCW REQUIREMENTS - HOURS OF WORK AND REST The STCW rest hour requirements apply to all seafarers with designated safety, pollution prevention and security duties as well as watchkeepers. In practice they are slightly stricter than those required by the ILO MLC and are those most likely to be enforced by Port State Control.' However, the MLC requirements, which are broadly the same, apply to all seafarers on board and not just to watchkeepers. For the purposes of both Conventions the Master is not exempt from the work/rest hour limits. In summary, the mai n STCW requirements are as follows: Minimum of 77 hours rest in any 7 day period; Minimum of 10 hours rest in any 24 hour period; The 10 hour rest period must not be split into more than 2 periods, one of which must be 6 consecutive hours, with th e interval between rest periods being not more than 14 hours. Under STCW, maintenance of individual records of seafarers' rest hours is mandatory and enforceable by Port State Control.8

7

8

66

More detaied intorm.ition on the rel.lticnshp betv.-een STCW 2010 and the ILO MLC can be found in the 'ISf Guidelines on the AppbcatJOn of the ILO Maritwne labour Convention'. This includes information about the use of the 'Mania Exceptions' v.ti.ch allow some addit:oonal fte)Jbiity with respect to compiance with STCW 2010. ICS has produced a co~uter program, 'ISF watchkeeper', vlhlch allows indiwdual rest hour records and a watch schedtile to be produced in accordance With IMOllLO Gt.ideioes, in additJOn to ched:ing compiance with the detai)ed prcwisions of STC\\f 2010 and the ILO MLC.

TANKER SAFETY GUIDE (CHEMICALS)

3.10.10 PREVENTION OF DRUG AND ALCOHOL ABUSE All ship operators and management companies should have a policy and procedures for controlling the u se of alcohol on board their vessels. The possession and use of illegal dru gs should be prohibited. The STCW Convention includes prescriptive requirements relating to the prevention of drug and alcohol abuse. However, some administrations may apply more stringen t limits, as do many shipping companies, especially those operating tankers.•

3.11

PERSONAL PROTECTIVE

EQUIPMENT (PPE) PPE protects the wearer from exposure to hazardous working condit ions. Some PPE also provides a barrier between the wearer and a hazardous environmen t. The effectiveness of that barrier will be lost if the PPE is used i ncorrectly or is of the wrong type. It is therefore essent ial th at the selection of PPE is based on a thorough assessment of the risks involved. All personnel w ho may be required to use PPE should be properly trained in its use and advised of its limitations. The material of chemical resistant suits, gloves, face shields, goggles, aprons and other items u sed sh ould be suitable for the product/cargo being handled . The manufacturer's instructions should be available and referred to as necessary w hen the equipment's suitability is checked prior to use. The IBC Code specifies certain PPE for specific individual cargoes.

3.11.1

Figure 3.1 - Typical PPE

ATMOSPHERE MONITORING EQUIPMENT Many chemical vapours are h eavier than air and tend to flow along the deck and accumulate in low spots. Modern chemical tankers have complicated deck structures and this, together with the comprehensive pipe work and other equipment fitted, provides numerous areas where h armful vapours can accumulate. In still weather conditions, particular care should be taken to prevent the accumulation of cargo vapours w ithi n the deck structure. In order that the cargo area remains safe, tests of the atmosphere on the cargo deck should be taken regularly, especially when highly volatile cargoes are bei ng loaded at a high rate and there is little wind to disperse the accumulated vapours. In addition to cargo vapours, displacement of inert gas from cargo tanks while loading also can lead to pockets of oxygen deficient atmosph ere on deck. If nitrogen is the inert gas being used, there will be no natural indication of the danger. This is because nitrogen is odourless and provides no sensory indication o r warning that the atmosphere is oxygen deficient. Atmosphere samples sh ould always be taken from different levels and it is recommended that all crew members worki ng on the cargo deck are provided with personal gas detector alarms appropriate to the cargoes being carried. However, the w earing of personal alarms is not a su bstitute for the regular sampling of the deck areas as described above. With experience, areas kn own to be more at risk from trapped cargo vapours will be known to th e crew and these areas can therefore be monitored more closely.

9

It is recommended that OCIM~ 'Gadeioes for the Control of Drugs and Akohol Onboard Ship' are consulted.

67

Figure 3.2 - PPE Use During Sampling

3.11.2 SAFE WORKING CLOTHING As a minimum, safe working clothing should consist of: Overalls or properly designed working clothing of cotton or other non-static generating material. The provision of self-reflecting patches on working gear should also be considered; Safety shoes with steel reinforced toe caps w ith chemical resistant soles; A properly fitting safety helmet; Working gloves; and Safety goggles.

It is important that working clothing is kept clean and in good condition as clothing contaminated with cargo and other residues can lead to health problems.

3.11.3 PROTECTIVE CLOTHING The protection of personnel from contact with toxic or corrosive chemical products should be primarily based on ensuring that the ship's containment system is well maintained and effective. The wearing of protective clothing is a secondary protective measure to avoid accidental exposure to hazardous substances should the primary containment system fail. Manufacturers' guidelines regarding the use of protective equipment should be followed.

3.11.4 TOXIC OR CORROSIVE SUBSTANCE PROTECTION The crew should always wear adequate protective clothing when opening equipment which may contain toxic or corrosive substances, for example when ullaging and sampling, connecting and disconnecting hoses, opening sighting ports, working within the manifold area, entering pumprooms and tanks, investigating leaks and dealing with spillages on deck.

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TANKER SAFETY GUIDE (CHEMICALS)

For operations i nvolving toxic products it is important that appropriate PPE (which may include a full chemical suit) is worn when: Inspecting pipelines and equipment for leaks; Dealing with accidental leaks and spillage; Connecti ng and disconnecting hoses and loading arms; Taking ullages and cargo samples; and Opening up pumps and equipment (unless certified gas free).

3.11.5 CHEMICAL RESISTANT CLOTHING (PROTECTIVE SUITS) A protective suit should always be used when working i n envi ronments where there is a risk of accidental exposure to products or their vapours. There is a risk of exposure during operations at the vessel's manifold when connecting and disconnecti ng hoses, duri ng tank and line sampling, and tank cleaning. Hazardous products in liquid or vapour form can be absorbed by the body via the skin. This absorption of product via the ski n is i ncreased in hot and humid conditions when the (body) skin is sweati ng. A protective suit with leak proof fastenings and manufactured from a material resistant to the products being handled is therefore essential when exposure can be expected, even if it is only in exceptional sit uations. If a protective suit has been contaminated with a hazardous product, it should first be washed or hosed down thoroughly before removal from the wearer. The protective suit should then be properly cleaned in accordance with the manufacturer's guidelines, and dried prior to being stored i n a ventilated space designed for the purpose. Correct cleani ng w ill ensure a longer service life for the protective suits and ensure their readiness for future use. Reference should also be made to the manufacturer's i nstructions regarding maintenance and care of the suit and its fittings.

3.11.6 TYPES OF CHEMICAL RESISTANT CLOTHING The type and degree of protection required is dependent on the physical, ch emical and/or toxic properties of the products being handled . Factors such as whether the job is continuous or intermittent, and the envi ronmental conditions prevailing must also be taken into account. Material Safety Data Sheets (M SDS) and the company's PPE matrix (see Appendix 10) should provide advice on the correct type of protective suits and other associated PPE to use when exposure to a product is possible. Ideally, the protective suit should combi ne th e maximum level of protection with the greatest degree of comfort. Various materials are used to manufacture chemical protective suits. Each material has different chemical resistant properties. The manufacturer of a protective suit must provide a chemical resistance list to indicate for which chemicals a suit may be used and which restrictions might be applicable. This list should be referred to prior to use. Chemical resistant clothi ng ranges from f ull body protection suits to aprons, bib and brace overalls, leggings and three-quarter length coats. Protection should be proportional to the risk to avoid excessive discomfort due to over protection. However if any doubt exists the level of safety protection should be i ncreased. The categorisation into types of chemical protective clothing is an attempt to differentiate between different general levels of risk. The determination of the actual risk level should follow from a risk assessment, which takes all relevant parameters into account. Such parameters migh t include the nature of the chemical, temperature, pressure, quantity of product, parts of the body likely to be exposed, climatic conditions and the intensity of work.

There are two principal sets of international standards for chemical protective clothing: the European Committee for Standardisationflnternational Organization for Standardization (IS0) 10 and the US National Fire Protection Association (NFPA) classifications. European/ISO classification: Type 1: Gas-tight Chemical Protective Suit (EN 943-1) Type 1a: Gas-tight chemical protective suit to be used in conjunction with a breathable air supply independent of the ambient atmosphere worn inside the suit; Type 1b: Gas-tight chemical protective suit to be used in conjunction with a breathable air supply independent of the ambient atmosphere supplied from outside the suit; and Type 1c: Gas-tight chemical protective suit to be used in conjunction with breathable air providing positive pressure where the suit includes the face piece (external air supply); Type 3: Full body protective clothing with liquid-tight connections between different parts of the clothing and, if applicable, with liquid-tight connections to component parts, such as hoods, gloves, boots, visors or respiratory protective equipment (EN 14605); Type 4: Full body protective clothing with spray-tight connections between different parts of the clothing and, if applicable, spray-tight connections to component parts, such as hoods, gloves, boots, visors or respiratory protective equipment (EN 14605); and Type 6: Chemical protective suits (Type 6) and partial body protection (PB 6) are intended to be used in cases where risk has been assessed as low and a full liquid permeation barrier is not necessary, i.e. when wearers are able to take timely adequate action when their clothing is contaminated. Type 6 and PB 6 protective clothing are intended to protect from a potential exposure to small quantities of spray or accidental low volume splashes (EN 13034). US NFPA classification: level A protection should be used when: 1.

The hazardous substance has been identified and requires the highest level of protection for skin, eyes, and the respiratory system based on either the measured (or potential for) high concentration of atmospheric vapours, gases, or particulates; or the site operations and work functions involve a high potential for splash, immersion, or exposure to unexpected vapours, gases, or particulates of materials that are harmful to skin or capable of being absorbed through the skin;

2.

Substances w ith a high degree of hazard to the skin are known or suspected to be present, and skin contact is possible; or

3.

Operations must be conducted in confined, poorly ventilated areas, and the absence of conditions requiring level A has not yet been determined.

(NFPA 1991 - Standard on Vapor-Protective Suits for Hazardous Chemical Emergencies) level B protection should be used when: 1.

The type and atmospheric concentration of substances have been identified and require a high level of respiratory protection, but less skin protection.

2.

The atmosphere contains less than 19.5% oxygen; or

3.

The presence of incompletely identified vapours or gases is indicated by a direct-reading organic vapour detection instrument, but vapours and gases are not suspected of containing high levels of chemicals harmful to skin or capable of being absorbed through the skin.

(NFPA 1992 - Standard on liquid Splash-Protective Suits for Hazardous Chemical Emergencies)

10 lnaeasll"lglY, European Standards (pmfixed EN + European Norm) are be9"lg superseded by lntematJOnal Standards (prefixed ISO).

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TANKER SAFETY GUIDE (CHEMICALS)

Level C protection should be used when: 1.

The atmospheric contaminants, liquid splashes, or other direct contact will not adversely affect or be absorbed through any exposed skin;

2.

The types of air contaminants have been identified, concentrations measured, and an airpurifying respirator is available that can remove the contaminants; and

3.

All criteria for the use of air-purifying respirators are met.

Level D protection should be used when: 1.

The atmosphere contains no known hazard; and

2.

Work functions preclude splashes, immersion, or the potential for unexpected inhalation of or contact with hazardous levels of any chemicals.

Protective clothing is referenced under European/ISO and US standards respectively. Up to date standards should be consulted.

Protection will only be as good as the weakest link and it is therefore important that gloves, boots and head gear, including face protection, offer the same degree of chemical resistance as the remainder of the clothing. Proper sizing of the clothing is essential since an overly large suit can mean the expected level of protection will not be met and may be uncomfortable. Personnel using the protective suits should be properly trained for the type of suit they are using. Before moving into the working area with Type 1/Level A and Type 3/Level B suits it is essential that a second properly trained person inspects the suit and confirms that it is being properly worn. Use of a higher level of protection w ill generally also involve a higher level of exertion, especially in adverse climatic conditions. An assessment of the user's fitness to wear a particular suit type should therefore be conducted. It is recommended that companies issue guidelines for the maximum time a person is allowed to work in a Type 1/Level A and Type 3/Level B protective suit. At all times protective suits should be maintained as per the manufacturers' instructions. Any defects must be repaired or the suits put out of service.

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Figure 3.3 - Protective Suit Types

When selecting appropriate chemical resistant protective clothing, the manufacturers' instructions should be consulted to ensure that the clothing provides the degree of protection specified as being required in the product's MSDS.

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TANKER SAFETY GUIDE (CHEMICALS)

3.11.7 EYE PROTECTION Eyes are particularly vulnerable to injury from corrosive and toxic liquids and vapours. It is therefore essential th at they receive appropriate and particular con sideration when assessing the need for personal protection. There is a wide range of eye protectors available for ch em ical hazards. Care should be taken to evalu ate the ch em ical hazard properly, guided by the cargo's MSDS, in order to select the eye protector accordingly. There are three types of eye protectors to ch oose from: Safety goggles give complete chemical and mechanical eye protection, and can gen erally be worn comfortably over most spectacles; Face shields, usually combi ned with a safety helmet, provide eye and face protection from splashes of liquid and mechanical hazards, but n ot against vapour hazards. They should be worn when disconnecti ng hoses at the manifold or during any other operation where there is a risk of being splashed or sprayed w ith product under pressure; and Safety spectacles, with o r without lateral protection (side shields), are available with different lens materials. Safety spectacles are not designed to be worn over normal spectacles. These are designed to protect the eyes from dust and debris while chippi ng or carrying out si milar tasks. These are not suitable eye protection in chemical environments.

3.11.8 HAND PROTECTION Hands are very vulnerable to injury, and hand protection can range from that agai nst si mple dirt and dust contamination to the provision of full protection agai nst toxic and corrosive products. As with all protective equipment it is i mportant to match the type of glove to the hazard to which hands are exposed. A further consideration is that the glove should still provide sufficient movemen t to allow the crew member to perform the tasks expected and also to protect the wearer from heated surfaces. PVC or rubber gloves are available when handling chemical products. They come in a range of thicknesses and weights, and the choice will depend on the cargoes being h andled. Neoprene or nitrile rubber gloves have excellent resistance to solvents, petroleum products, oils and many chemicals. The cargo's MSDS should be consulted. The choice of glove w ill be dependent o n the resistance of the glove's material to the chemicals bei ng handled and whether the w orking conditions are conti nuous o r i ntermittent. Gloves with long cuffs which can extend over the sleeves of normal clothi ng are preferable.

3.11.9 FOOT PROTECTION Rubber or PVC boots need to be worn w h en there is a risk of coming i nto contact with corrosive o r toxic ch emicals. Boots that have reinforced toe caps are preferable as they provide protection against physical i njuries.

3.11.10 PPE MATRIX It is recommended that the company prepares a PPE matrix which clearly show s what PPE is required to be worn for the many different types of operations o n board. An example of a PPE matrix is included at Appendix 10.

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3.11.11 RESPIRATORY PROTECTION Respiratory protective equipment is designed to provide the user with an adequate supply of fresh air when worki ng in an area where toxic vapours could be present. It usually consists of a sealed face piece connected to either a self-contai ned air source or to a fresh air line. The face mask m ust be checked and adjusted to ensure it is air-tight. It should be noted that the presence of facial hair can adversely affect the mask's seal. Consideration should be given to the development of company policy regarding the use of Self-Contained Breathing Apparatus (SCBA) or air line breathing apparatus by personnel with facial hair.

3.11.12 CANISTER OR FILTER TYPE RESPIRATORS Canister or filter type respirators are designed to absorb specific toxic or poisonous elements, dust and debris but do not protect the wearer from an oxygen deficient atmosphere.

Filter masks may be ineffective in protecting the wearer from cargo vapours and do not protect the wearer from an oxygen deficient atmosphere.

Although filter masks are effective i n protecting the wearer from specific vapours in an atmosphere with a normal oxygen content of 21 %, most vessels handle different types of cargo simultaneously. Ensuri ng that the mask provides adequate protection against a combination of vapours will therefore be very difficult to manage. Filter masks should never be used i n enclosed spaces or areas on board where the oxygen content of the atmosphere may be insufficient to sustain life. Due to their limitations, filter masks should not be used on board chemical tankers to protect crew involved in cargo operations. Filter masks should only be used to protect wearers from dust and other debris in the air when carrying out maintenance tasks such as chippi ng paintwork or when using gri nding tools.

Filter masks should not be used during cargo operations and their use on board must be strictly controlled.

3.11.13 SELF-CONTAINED BREATHING APPARATUS (SCBA) SCBA provides the wearer with a fresh air supply and therefore protects the wearer from the inhalation of toxic vapours and from the dangers of an oxygen deficient atmosphere. SCBA sets consist of a compressed air cylinder attach ed to a carrying frame and harness worn by the user. Air is provided to the user via a full face mask which can be adjusted to give an air-tight fit (see Section 3.11 .11). The air supply is limited to the capacity of air in the cylinders and an alarm device is fitted to warn the wearer when the air supply is getting low. SCBA should be stowed outside hazardous areas in places that are easily accessible and should be maintained ready for immediate use. Air cylinders, including spares, should be kept fully charged and the adjusting straps kept slack so as to enable th e Self-Contained Breathing Apparatus (SCBA) to be quickly donned in an emergency. The IBC Code specifies the number of SCBA sets which have to be provided on board each vessel. Guidance may be available from the administration on the use of SCBA including routine maximum individual daily use and required rest periods.

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3.11.14 AIR LINE BREATHING SYSTEM Air is supplied via a small diameter hose to a connection on the wearer's belt which is then connected to a full face mask (see Section 3.11 .11). Air is supplied from either a bank of air cylinders or from a specifical ly designed compressed air line. It is essential that the air supply is filtered, clean and free of contami nants. When used in an enclosed space, the wearer should always be provided with a separate self-contained supply of ai r, such as a short duration breathi ng apparatus, in case the main air line supply fails. Guidance may be available from the admi nistration on the use of ai r line breathing apparatus including routine maximum individual daily use and requi red rest periods.

3.11.15 EMERGENCY ESCAPE RESPIRATORY PROTECTION Ships certified for the carriage of certain cargoes listed in the IBC Code are required to be provided with respiratory and eye protection sufficient for every person on board for emergency escape purposes. Escape sets provide a supply of air for at least 15 minutes. This equipment is for use during emergency escape situations only and should not be used for any other purpose.

3.11.16 MAINTENANCE Equipment must be properly maintai ned in order to ensure it is at all times fit for purpose. The IBC Code requires that breathing apparatus is i nspected by a responsible officer at least once a month, and i nspected and tested by an expert at least once a year. The expert may be one of the ship's officers who will have received flag state recognised training in breathing apparatus mai ntenance. Defects must be corrected promptly. A record should be kept of all inspections, tests, maintenance and repai rs and a sufficient stock of spares should be kept on board. Air cylinders should be refilled as soon as possible after use and masks and helmets kept clean and disinfected.

3.11.17 TRAINING Practical demonstrations and traini ng in the use of all types of breathing apparatus on board should be carried out regularly to ensure that all personnel gain experience in their use. Familiarity gai ned through regular practice will lead to confidence in the use of the equipment. Only trained personnel who are confident and capable in the use of breathi ng apparatus should use the equipment.

7S

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CHAPTER4 REGULATORY FRAMEWORK

4

REGULATORY FRAMEWORK

This chapter describes the international regulatory requirements of particular importance to chemical tanker operations and focuses in particular on environmenral protection, the safety requirements of the IBC Code and new /MO regulations on inerting.

4.1 4.2

Regulatory Guidelines

4.3 4.3.1

IMO MARPOL Regulations MARPOL Annex I - Prevention of Pollution by Oil MARPOL Annex II - Prevention of Pollution by Noxious Liquid Substances MARPOL Annex VI - Prevention of Air Pollution from Ships

4.3.2 4.3.3

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4.4

4.4.1 4.4.2 4.4.3 4.4.4

IMO International Code for the Construction and Equipment of Ships Carrying Dangerous Chemicals in Bulk (IBC Code) Tank types Summary of IBC Code requirements lnerting and padding Damage stability

4.5

Inert Gas Requirements for Chemical Carriers

4.6

IMO Ballast Water Convention

4.1

INTRODUCTION This Guide is primarily concerned whh the safety of the vessel and its crew, especially with respect to cargo operations carried out both at sea and in port. However, with the growing focus on improving environmental performance, the crews of chemical tankers need to have a clear unders1anding of pollution prevention regulations. Many tasks undertaken during cargo handling operations on a chemical tanker are dictated by the need to comply with environmental regulations in order to avoid pollution of the sea and air. These addhional tasks mus1 be performed safely, and an understanding of their purpose is essential for those in charge of cargo operations. Ships' officers should familiarise themselves thoroughly with the types of cargo the vessel is permitted to carry, and adhere at all times to operational procedures with respect to cargo handling, tank cleaning, slop handling, residue discharge, ballasting and deballasting operations. The Master should ensure that the vessel does not discharge into the sea any cargo residues, or mixtures of residue with water, unless such discharges are made in full compliance with the applicable regulations. The following sections only provide a brief description of the various environmental regulations that apply to chemical tankers. They are provided as guidance only and for more precise detail the actual regulations themselves should be consulted.

4.2

REGULATORY GUIDELINES When necessary to support or clarify the intention of its regulations, !MO develops appropriate guidelines. An example of such Guidelines of relevance to the safe operation of chemical tankers is MSC-MEPC.2/Circ.3. This circular provides advice on the basic elements of a shipboard occupational health and safety programme, and is included as an Annex to the IBC Code.

4.3

IMO MARPOL REGULATIONS The International Convention for the Prevention of Pollution from Ships, 1973, as modified by the Protocol of 1978 and subsequent amendments, known as MARPOL, is the principal IMO Convention covering the protection of the marine environment. The MARPOL Convention includes six annexes; Annex I

Regulations for the Prevention of Pollution by Oil; Annex II

Regulations for the Control of Pollution by Noxious Liquid Substances in Bulk; Annex Ill

Regulations for the Prevention of Pollution by Harmful Substances Carried by Sea in Packaged Form; Annex IV

Regulations for the Prevention of Pollution by Sewage from Ships; Annex V

Regulations for the Prevention of Pollution by Garbage from Ships; and Annex VI

Regulations for the Prevention of Air Pollution from Ships. MARPOL regulations apply to all ship types. However, Annexes I and II are particularly applicable to chemical tanker cargo operations. The latest edition of the MARPOL Convention should always be available on board the vessel.

79

On completion of the removal of residues from a tank, in compliance with the applicable MARPOL Annex I o r II regulations, the tank can be considered as clean. Further preparation to bring cargo tanks to a commercially acceptable standard are not subject to the restrictions imposed by MARPOL unless cleaning substances regulated by MARPOL are used.

4.3.1

MARPOL ANNEX I - PREVENTION OF POLLUTION BY OIL Annex I defines an oil product as oil in any form including crude oil, fuel oil, sludge, oil refuse and refined products (other than petrochemicals). It therefore applies to both the operational discharge of oil from cargo operations as well as the disposal of oily waste from machinery spaces. The following focuses on how Annex I applies to cargo operations. Chemical tankers frequently carry oil products such as lube oils and clean refined petroleum products such as gas oil, gasoline and kerosene. When transporting these products the vessel w ill have to comply with the MARPOL Annex I regulations.

The MARPOL Annex I regulations mandate construction. equipment and operational measures designed to prevent operational and accidental discharges of oil into the sea.

Annex I requires that: All vessels carry and keep up to date an approved Oil Record Book (Part II); Oil Discharge Monitoring Equipment (ODME) is installed to monitor, control and record the oil content of any residues being discharged overboard; and Cargo spaces are protected by a double hull. The following considerations should be taken into account to ensure compliance with MARPOL Annex I. Following the unloading (discharge) of an oil cargo, the tank is cleaned and the tank washings (slop water'') are transferred to a slop tank. In this slop tank, the slops separate, aided by heating if necessary, with the oil floating on top of water due to its lower specific gravity. The effectiveness of the separation process is checked with an oil water interface detector. This enables the amount of water and oil in the tank to be calculated. The water is then pumped from the bottom of the tank and discharged overboard. The ODME constantly samples the water being discharged to ensure that the oil content of the water does not exceed limits specified under MARPOL Annex I. Should the content of oil exceed the specified limits an alarm is raised, the overboard valve is automatically closed, and the contaminated water is returned to the slop tank via a return line. As a further precaution the overboard discharge outlet is sighted above sea level of slop water can also be monitored visually.

so that the discharge

The remaining slops are retained on board and must be disposed of to an approved shore reception facility. Annex I specifies that the vessel should be underway during the disposal of slop water and should be beyond a specified minimum distance from the nearest land. There are particular defined locations, known as 'special areas', where the disposal of slops is strictly prohibited. See MARPOL Annex I (Chapter 4, Regulation 34b). Oil Record Book All operations involving the loading, discharging of oil products and the ballasting and cleaning of cargo tanks after the carriage of oil products should be recorded in the ship's Oil Record Book (Part II).

11 'Slop water' includes oil~ oily mixtU'Jl!S from the cargo are.i of an oil tanker as referenced in MA.R.POL Annex t. Chapter 4, Regulation 34.

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4.3.2 MARPOL ANNEX II - PREVENTION OF POLLUTION BY NOXIOUS LIQUID SUBSTANCES All liquid cargoes carried in bulk are defined by MARPOL as either Oil (Annex I) or as Noxious Liquid Substances (NLS) (Annex II). The MARPOL Annex II regulations assign pollution criteria for all regulated NLS. Each product is assessed by IMO against agreed criteria, and assigned a category as follows; Category X NLS which, if discharged into the sea from tank cleaning or deballasting operations, are deemed to present a major hazard to either marine resources or human health and which therefore justify the prohibition of the discharge into the marine environment; Category Y NLS which, if discharged into the sea from tank cleaning or ballasting operations, are deemed to present a hazard to either marine resources or human health or cause harm to amenities or other legitimate uses of the sea and therefore justify a limitation on the quality and quantity of the discharge into the marine environment; Category Z NLS which, if discharged into the sea from tank cleaning or ballasting operations, are deemed to present a minor hazard to either marine resources or human health, and therefore justify less stringent restrictions on the quality and quantity of the discharge into the marine environment; and Other substances (OS) Substances found to fall outside of category X, Y or Z, as defined in the MARPOL Annex II regulations, and considered to present no harm to marine resources, human health, amenities or other legitimate uses of the sea when discharged into the sea from tank cleaning and ballasting operations. Products that are categorised as X, Y or Z are listed in Chapter 17 of the IBC Code with some category Z products being listed in Chapter 18. Even though the Code's title mentions dangerous chemicals it does in fact cover many other different liquid mixtures ranging from harmless chemicals to vegetable oils and animal fats. Other substances (OS) are products that have been reviewed and are considered to present a minimal hazard to the marine environment such as ethanol and water. These are not assigned a pollution category and are listed in Chapter 18 of the IBC Code. The IBC Code also covers the safety aspects of the carriage of NLS and establishes construction, equipment and operational standards for the handling of these products.

The MARPOL Annex II regulations mandate equipment and operational measures designed to minimise the volume of cargo remaining in the cargo tanks after unloading (discharging).

Unloading (discharging) of cargoes and the disposal of residues after cleaning should be carried out in accordance with the vessel's Procedures and Arrangements (P&A) Manual. The P&A Manual describes how the vessel's pumping and stripping system is to be operated in order to ensure that the tanks are effectively stripped in order to comply with the MARPOL Annex II regulations: Category X residues cannot be discharged overboard. On completion of discharge, the tank is washed and the tank washings pumped ashore. This procedure is called a prewash. This operation has to be monitored and approved by the relevant port authority representative and an entry must be made in the Cargo Record Book;

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Category Y residues remaining in the tank after stripping i n accordance with the P&A Manual can be discharged to the sea while tank cleaning provided that the conditions stipulated by MARPOL Annex II are met. High viscosity or high melting point Category Y products may also require a prewash (the same as for Category X products) if, on discharge, the temperature or characteristics of the product mean that the tank cannot be stripped in compliance w ith the stripping criteria; Category Z residues remaining in the tank after stripping in accordance w ith the P&A Manual can be discharged to the sea while tank cleaning, provided that the conditions stipulated by MARPOL Annex II are met; and Tanks can be washed overboard via an underwater discharge outlet. provided that the conditions stipulated by MARPOL Annex II, Chapter 5, Regulation 13 are met. This ensures that any small traces of the product are dispersed by the action of the ship's propeller. The regulations require that the vessel is proceeding en route at a speed of at least 7 knots, at least 12 miles from the nearest land and in water at least 25 metres deep. Before a cargo can be loaded the vessel must have the specific cargo listed on its ! MO Certificate of Fitness (COF) which is issued by the flag state. This is evidence that the vessel has been constructed, operated and is manned in full compliance with the !BC Code (see Section 6.3.3 of this Guide). Tripartite agreement New cargoes may be proposed for carriage which have not yet been formally assessed by !MO. In these circumstances th e relevant authorities of the country where the cargo originates, the authorities of the receiving country and the flag state of the vessel agree on interim carriage requirements based on the best information available. This arrangement is known as a 'tripartite agreement'. The vessel's COF will contain an addendum listing the tripartite cargoes which the vessel is permitted to carry. As soon as possible, but not later than 30 days after the agreement has been reached, the government of the producing or shipping country is required to notify IMO and provide details of the substance and the provisional assessment. IMO MEPC.2 Circular IMO publishes a list of current tripartite agreements on an annual basis in a docum ent titled MEPC.2/Circular. The circular also lists the tank cleaning agents that have been ap;proved for use on board chemical tankers. The latest version of this document should be kept on board the vessel. Permitted cargoes The vessel may only load cargoes that are included on the vessel's COF or an adden dum to the COF. The shipper of the product is required to provide the vessel with a full description of the cargo including its IBC Code shipping name. The ship should refuse to accept a cargo if the full shipping name and description of the product is not provided. Bio fuel s and bl ended products Bio fuels typically consist of MARPOL Annex II products such as alcohols, fatty acid methyl esters (FAME) or vegetable oils blended w ith MARPOL Annex I products such as gasoline and diesel. The proportion of each product in the final blend determines under which MARPOL Annex the cargo is to be transported. Under present regulations, all blended bio fuels with more than 25% of the blend made up of an Annex II product have to be transported according to MARPOL Annex II regulations. For blended bio fuels with less than 25% of the blend made up of an Annex II product, the bio fuel can be transported under MARPOL Annex I regulations, provided that the vessel's ODME has been approved for the mixture being transported. 12

12 Until 1 January 2016, MAR.POL Annex I bio fuef blends may be carried when the ship's ODME has not been approved for the mixture carried provided that tank residues and all tank washings are pumped ashore.

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TANKER SAFETY GUIDE (CHEMiCAL5)

SOLAS Chapter VI, Regulation 5-2, prohibits the physical blending of bulk liquid cargoes during a sea voyage. Physical blending refers to the process whereby the ship's cargo pumps and pipelines are used to circulate internally two or more different cargoes with the intent of producing a cargo with a new product specification. This prohibition does not prevent the Master from undertaking cargo transfers for the safety of the ship or protection of the mari ne environment i n an emergency. Blending operations in port should be planned to ensure compliance with the applicable MARPOL regulations. Cargo Record Book All operations i nvolving the loading, discharging and cleaning of tanks after the carriage of NLS products should be recorded in the vessel's Cargo Record Book.

4.3.3 MARPOL ANNEX VI - PREVENTION OF AIR POLLUTION FROM SHIPS MARPOL Annex VI regulates exhaust emissions from machi nery, and vapour emissions from cargo operations (it also regulates the reduction of CO, emissions which are beyond the scope of this Guide). In order to reduce exhaust emissions, the vessel 's crew should ensure that the ship's machinery is well maintai ned and that power output closely matches demand. Some national and port administrations require that cargo vapours are returned to shore for treatment or capture while loading so as to reduce the negative effects of venting cargo vapours to air. Many chemical tankers are provided with vapour return systems complying with the MARPOL Annex VI requirements.

4.4

IMO INTERNATIONAL CODE FOR THE CONSTRUCTION AND EQUIPMENT OF SHIPS CARRYING DANGEROUS CHEMICALS IN BULK (IBC CODE) The IBC Code is mandatory via reference to SOLAS and MAR POL." The purpose of the IBC Code is to provide an international standard for the safe carriage, in bulk by sea, of noxious liquid substances. The Code specifies design and construction standards and specifies the equipment that vessels must carry in order to ensure the safety of the crew and minimise risk of damage to the environment. The Code addresses both safety and environmental issues and th ere is a degree of overlap with the MARPOL Annex II regulations. Chemical tankers are designed as either a Type 1, 2 or 3 ship depending on the safety and environmental containment standard to which they are built. In practice, vessels are usually built to transport a com bination of cargo types with some tanks built to Ship Type 1 and the remainder to Ship Type 2 or Ship Type 3 construction requirements. The IBC Code chemical tanker design types are as follows: Tanks on ships of Type 1 provide the highest degree of protection and contai nment, and th ese tanks are used to transport cargoes with a severe environmental and safety hazard. The tanks must be located beyond a minimum, specified distance from the hull; Tanks on ships of Type 2 are designed to transport cargoes with a moderately severe environmental and safety hazard. The tanks must also be located beyond a minimum, specified distance from the hull;

13 for ships built prior to 1986 the corresponding rxJ;>lication is knO'M"I as the BCH Code.

83

Tanks on ships of Type 3 have no restrictions on their location w ithin the cargo area and can transport cargoes with less severe environmental and safety hazards. Under the IBC Code the vessel's hull can form part of the tank's structure.

TYPE 1 SHIP

TYPE 2 SHIP

b must be no less than 11.5m or B/5, whichever is least, but no less than 0 . 76m h must be no less than 6m or B/15, whichever is least, but no less than O. 76m

h must be no less than 6m o r B/15, whichever is least, but no less than 0 .76m

b must be no less than 0.76m

b

Th

'-

Ih B

~

B

Figure 4.1 - Type 1 Ship

Figure 4.2 - Type 2 Ship

TYPE 3 SHIP

Figure 4.3 - Type 3 Ship

4.4.1

TANK TYPES As well as identifying different ship types for the carriage of cargoes with varying degrees of safety or environmental risk the IBC Code defines four different types of tank. Chapter 17 of the Code specifies both the ship type and tank type required for particular products. The different tank types are: Independent tank means a cargo containment envelope, which is not contiguous w ith or part of the hull structure. An independent tank is not essential to the structural completeness of the ship's hull.

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TANKER SAFETY GUIDE (CHEM,CALS)

Figure 4.4 - Independent Tank Integral tank means a cargo containment envelope which forms part of the ship's hull and which may be stressed in the same manner and by the same loads which stress the contiguous hull structure. An integral tank is normally essential to the structural completeness of the ship's hull.

Figure 4.5 - Integral Tank Gravity tank means a tank having a design pressure not greater than 0.07 MPa gauge at the top of the tank. A gravity tank may be independent or integral. A gravity tank must be constructed and tested according to recognised standards, taking account of the temperature and the relative density of cargoes carried. Pressure tank means a tank having a design pressure greater than 0.07 MPa gauge. A pressure tank must be an independent tank and of a configuration permitting the application of pressure vessel design criteria according to recognised standards.

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4.4.2 SUMMARY OF IBC CODE REQUIREMENTS The IBC Code specifies how the vessel's design and equipment must be arranged so as to limit the exposure of the crew to toxic vapours. Cargo vapours In order to minimise the release of toxic vapour emissions the Code specifies how cargo vapours are to be vented or returned to shore, and how cargo tank contents are to be gauged. Virtually all toxic cargoes require closed or restricted tank gauges to prevent crews being exposed to unsafe concentrations of toxic vapours. Tanks containing toxic products have to be provided with separate venting systems which have to be sited a safe distance away from the working deck and from the accommodation spaces. Ventilation systems The inlet and outlet of ventilation systems for working spaces such as pumprooms are required to be sited a specified distance from the accommodation spaces. The siting of accommodation ventilation system intakes is also specified and the ventilation system has to be able to recirculate air within the accommodation should an accidental release of toxic vapour occur. Preventing spills Tanks designed for toxic products must be provided with high level alarms that give an audible and visual alarm should the level in the tank reach a certain level. Tanks designed for the most severely acute toxic products must have a further overflow control system which is independent of the high level alarm. Piping systems Piping and pumping systems for toxic products have to be segregated from other t anks and line systems. This is achieved on many chemical tankers by having separate pumps, pipelines and vents so that complete segregation is achieved by the design. On ships with common pipeline systems, toxic products must be separated by at least two physical barriers by the use of removable spool pieces, blank flanges or other appropriate means.

It is important that the packing and jointing used on pipelines, flanges and cargo valves are fully compatible w ith the cargoes the tanks are certified to carry. Correct maintenance and tightening of valves and glands is essential in order to prevent leaks. Adjacent stowage The IBC Code prohibits the stowage of most toxic products adjacent to oil fuel tanks. PPE The IBC Code specifies the amount and type of chemical Personal Protective Equipment (PPE) to be carried on board a ship (see Section 3.11).

4.4.3 INERTING AND PADDING For cargoes that react with air or moisture in the air, the IBC Code requires the atmosphere in the vapour space to be controlled. This is usually achieved by using an inert gas such as nitrogen which is either applied as a pad (applied after loading the tank) or prior to loading by f ully inerting the vapour space. lnerting or padding may also be required for cargo quality control purposes. The IBC Code recognises four methods of environmental control for cargo tanks on chemical carriers: lnerting: By filling the cargo tank and associated piping systems and the spaces su rrounding the cargo tanks with a gas or vapour which will not support combustion, and which w ill not react with the cargo, and maintaining that position.

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TANKER SAFETY GUIDE (CHEMiCAL5)

Padding: By filling the cargo tank and associated pipi ng systems with a liquid, gas or vapour which separates the cargo from the air, and mai ntaining that position. Drying: By filling the cargo tank and associated piping systems with moisture-free gas or vapour with a dewpoint of or below at atmospheric pressure, and maintaining that position.

-40·c

Ventilation: Forced or natural. When inerting or padding is required, care should be taken to ensure that there is an adequate supply of the inerting or padding agents on board, in order that the required conditions can be maintai ned in the cargo tank vapour space throughout the i ntended voyage (see Section 6. 7.8 of this Guide).

4.4.4 DAMAGE STABILITY The IBC Code specifies reserves of stability that are required to be achieved for a range of standard ship damage scenarios. Operationally, compliance with IBC Code requirements is necessary in addition to compliance with the applicable SOLAS requirements for intact stability. Compliance with both sets of requirements should be verified against the actual loading conditions prior to sailing. Flag admi nistrations and port states can require chemical tankers to demonstrate that operational loading conditions have been verified. Adequate stability information and means of checking compliance are required to be available. Although calculation of intact stability may be relatively straightforward, damage stability calculations are significantly more complicated. However, with the widespread availability of software to assist with th ese calculations, the verification of damage stability can also be routinely carried out either on board or ashore.

4.5

INERT GAS REQUIREMENTS FOR CHEMICAL CARRIERS The provision and use of an inert gas system is specified by the SOLAS Convention. To meet the SOLAS requirements for non-flammability, an inert gas system must be capable of deliveri ng inert gas with an oxygen content of not more than 5% by volume, in th e inert gas main at any required rate of flow. The system must also be able to maintain a positive pressure i n the cargo tanks at all times, such that the tank atmosphere has an oxygen content of not more than 8% by volume. Where required, the system must be capable of delivering i nert gas at a rate of 125% of the maximum pumpi ng capacity of the vessel and must be capable of maintaining an i nert atmosphere of less than 8% oxygen w ithin the ullage space of the tank. Flag administrations may accept i nert gas systems with a lower capacity if the maximum rate of discharge of cargoes being protected by the system is restricted to 80% of the i nert gas capacity. The system must be capable of delivering inert gas with an oxygen content of not more than 5% by volume in the inert gas supply mai n to the cargo tanks at any required rate of flow. An inerted tank's atmosph ere should not support combustion. This is achieved by maintai ning the tank's atmosphere at less than 8% oxygen content. It should be noted that some cargoes may require the maintenance of the required inert atmosphere at a specified percentage below 8% oxygen within the ullage space of the tank (see Section 1.3.2). From 1 January 2016, new and amended SOLAS regulations concerning the use of i nert gas (adopted by IMO i n May 2014) will apply to certai n ch emical tankers: SOLAS Chapter 11-2, Regulation 4.5.5, which introduces a lower limit of 8,000 dwt for new tankers required to be fitted with an inert gas system; and SOLAS Chapter 11-2, new Regulation 16.3.3 addresses the application of inert gas on chemical tankers. The application of inert gas may take place after the cargo tank has been loaded, but before commencing unloading and must continue until that cargo tank is gas free. NB: Under this provision, nitrogen is the only acceptable inert gas.

87

The International Code for Fire Safety Systems (FSS) spells out SOLAS Chapter 11-2 requirements in greater detail, and provides international standards for fire safety systems. The latest requirements for inert gas systems in the FSS Code (adopted by IMO in May 2014) need not be applied to chemical tankers constructed before 1 January 2016: 1.

When carrying defined cargoes described, provided that they comply with the existing requirements for i nert gas systems on chemical tankers established by th e admi nistration, based on the guidelines developed by IMO; or

2.

When carrying flammable cargoes other than crude oil or petroleum products such as cargoes listed in Chapters 17 and 18 of the IBC Code, provided that the capacity of tanks used for their carriage does not exceed 3,000m 3 and the i ndividual nozzle capacities of tank washing machi nes do not exceed 17.Sm 3/h and the total combined throughput from the number of machines in use in a cargo tank at any one time does not exceed 11 Om'lh.

Detailed requirements for the operational capability of inert gas systems, where required, are contained withi n the FSS Code.

SOLAS and the FSS Code should be referenced to determine applicable inert gas requirements.

4.6

IMO BALLAST WATER CONVENTION The IMO Convention on Ballast Water Management (BWM) specifies how ballast i.s to be handled and treated so as to prevent the spread of invasive species from one geographical area to another. The Convention is expected to enter into force worldwide by 20 16. It is recognised that the discharge of ballast water has been responsible for the i ntroduction of alien species into sensitive coastal and inland waters which can seriously damage the local ecology. Ballast water management is considered a quarantine control procedure rather than a pollution matter. It is therefore addressed under a stand alone IMO Convention, and not included under MARPOL. Vessels must be provided w ith ballast water management plans. Vessels trading to many areas of the world are also required to comply with local ballast water regulations or where possible w ith voluntary requirements. Most local regulations currently require the vessel to carry out a deep water ballast water exchange during the ocean voyage. Ballast taken on board at the load port is pumped out or 'exchanged' with deep sea water. The operation has to be recorded and confirmation forwarded to the relevant authorities before deballasting can take place within port areas. In some ports the ballast is tested and has to be approved before deballasting can commence. Ballast water exchanges at sea should be carefully planned so as to ensure that no undue stress is placed on the hull and that the vessel's stability remai ns positive during the whole procedure. Special care should be taken to avoid unnecessary slack tanks and the operation should only be carried out under appropriate weather conditions. Ballast water management systems that treat ballast water to a specified biological standard are now increasingly being fitted to vessels and various designs and operating principl es are employed. Once the IMO BWM Convention has entered i nto force, chemical tankers that rem ain in service will be required to be retrofitted with type-approved treatment equipment at the first renewal survey following entry into force of the Convention.,. All crew are required to be familiar with the operation and mai ntenance of the equipment fitted on board their vessel, so far as this may be relevant to their duties, and records are required to be maintained of all ballasting and deballasting operations as required under the ship's ballast water management plan.

14 At the time of writing the 8\VM Convent:oon had not entered into force but was expected to do so shortly. However, the United States already requims new ships to fit treatment equipment in order to trade to US pons.

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CHAPTER 5

SHIP AND EQUIPMENT

5

SHIP AND EQUIPMENT

This chapter provides a general description of the cargo systems and related equipment typically found on chemkal tankers.

5. 1

Introduction

5.2

Cargo Tanks

5.3 5.3. 1 5.3.2 5.3.3 5.3.4 5.3.5 5.3.6 5.3.7

M onitoring Equipment Introduction Alarms and shutdowns Air supply to control systems Liquid level gauges Overlill detection systems Pressure indicating devices Temperature momtonng equipment

5.4 5.4.1 5.4.2 5.4.3 5.4.4 5.4.5

Atmosphere Monitoring General General precautions Oxygen analysers Flammable gas detectors Toxic gas detectors

5.5 5.5. 1 5.5.2 5.5.3 5.5.4 5.5.5

cargo Pumps General Deepwell pumps Cargo pumprooms Booster pumps Emergency cargo pumps

5.6

Piping Systems and Valves

5.7

Cargo Manifold

5.8

Venting Systems and PN Valves

5.9

Vapour Return Systems

5.10

Heating and Cooling Systems

5.11 5. 11 . 1 5. 11 .2

Tank Washing Systems Fixed t ank washing machines Portable tank w ashing machines and hoses

5.12 5. 12. 1

Gas Freeing Equipment Permanently installed gas freeing equipment Portable gas freeing equipment Venting outlets

5. 12.2 5. 12.3

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TAN<ER WETY QJIDE CCHEMICAlSI

5.13 5.13.1 5. 13.2 5. 13.3 5. 13.4 5. 13.5 5. 13.6 5. 13.7 5. 13.8

Inert Gas Systems Introduction Oxygen content Sources of inert gas Compressed nitrogen s1ored on board Liquid nitrogen stored on board Pressure swing adsorption (PSA) nitrogen generators Membrane separabOn nitrogen generators 011 fired inert gas generators

5.14 5.14. 1 5. 14.2 5. 14.3 5. 14.4 5. 14 .5

Cargo Hoses Introduction Certification, marking and testing Storage and maintenance Operational use Cargo hose connections

5.15 5. 15. t 5.15.2 5.15.3

Electrical Equipment and Installations in Hazardous Areas Introduction Certified safe electncal equipment Bonding and earthing

5.16

Ballast Pumprooms

5.17

Openi ngs in Deckhouses and Superstructures

5.1

INTRODUCTION This section describes the equipment found on board a typical chemical tanker. This equipment sh ould be maintained, and calibrated when necessary as recommended by the manufacturer, and suitable records kept. Chemical tankers are specialised vessels designed and built to transport a wide range of liquid cargoes in bulk. The ability to load many different grades of cargo at the same time requires the vessels to be provided with a large number of tanks of various sizes, and to be fitted with a complex cargo pumpi ng and piping system to ensure complete segregation between cargoes. Bei ng able to clean cargo tanks effectively between grades is an important design consideration.

5.2

CARGO TANKS Cargo tanks are frequently part of the hull structure and are constructed of either mild or stainless steel. M ild steel tanks are usually coated with either an inorganic zinc coati ng, an epoxy type coating or an advanced polymer coati ng. On modern double hull vessels, tank internals are largely obstruction free and th erefore relatively easy to clean.

Figure 5.1 - Cargo Tank

Cargo tanks are usually designed, as a minimum, to be able to load a full cargo corresponding to a full tank of sea water (specific gravity of 1.025). Should a cargo w ith a density greater than sea water be loaded then the vol ume of the cargo may have to be reduced proportionally so that the weight of the cargo does not exceed the design limitations of th e tank. Loading high density cargoes increases the slack tank effect which can result i n considerable sloshing and movement of the cargo should the vessel encounter bad weather on th e voyage. Due to the dangers of sloshing there may be volume restrictions imposed on the carriage of high density cargoes in non-strengthened tanks or other requirements to ensure that adjacent tanks are also loaded to a similar level so as to ensure that the tank bul kheads are appropriately supported on both sides.

91

Example of volume calculation for high density cargoes: 1,200m' tank (100% load capacity) x 1.025 = 1,230 tonnes maximum permitted weight. Should a cargo with a density of 1.4 kg/m' require to be loaded then: 1,230 tonnes (maximum weight permitted)/1.4 (density of the product)= 878.57m'. The tank should not be filled to more than 878.57m' by volume.

Cargo tanks on chemical tankers are usually strengthened to enable full cargoes of high density products to be carried. The degree of tank strengthening will vary from ship to ship and the crew must be aware of any weight or density restrictions that apply to the vessel. Cargo tanks can also be deck mounted stand alone units. These are usually cylindrical, constructed of stainless steel and may be insulated. As with integral hull tanks, deck tanks can be built to handle cargoes with high specific gravities. Due to their cylindrical shape they are also more prone to sloshing damage if only partially filled. In such cases guidelines are provided which indicate which combinations of cubic capacity and specific gravity should be avoided. This information is usually presented in a graphical format which will clearly show the loading conditions to be avoided.

The planning and loading of the vessel should consider the design characteristics of the cargo tanks, and ensure that the maximum weight which the tank is designed to load is not exceeded and that there is compliance with restrictions on filling ratios.

5.3

MONITORING EQUIPMENT

5.3.1

INTRODUCTION The main purpose of monitoring equipment is to protect the crew and the environment from contact with the cargo and to prevent the risk of fire and explosion. Monitoring equipment also allows many different operations to be carried out safely and simultaneously under fully controlled conditions. The reliability and accuracy of the information provided still depends on the correct interpretation of the information. Therefore there is a need to understand the capability and limitations of the equipment. The best source of detailed information about a particular system will be found in the manufacturer's instructions regarding testing, calibration, maintenance and the correct use of the equipment. Information overload and an over reliance on instruments m ust be guarded against. Operations should be planned so that the information that is provided by the monitoring equipment and other cargo handling equipment is capable of being effectively managed by the crew on duty. Information provided by monitoring equipment that is suspected to be inaccurate should be immediately checked by using back up equipment. Most equipment is provided with alarms which are activated when pre-set conditions are met. The crew should always be in f ull control of all operations being conducted. Should a situation develop where the monitoring of cargo operations cannot be properly controlled, then some operations should be stopped until they can be resumed under full control. Cargo tanks can be provided with the following monitoring equipment: Gauging equipment which measures the level of product in the tank and provides the information to a remote display; One or two high level alarms, working independently of the gauging equipment, which trigger an alarm when the level of cargo in the tank nears the maximum capacity;

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TANKER SAFETY GUIDE (CHEMiCAL5)

Pressure sensors which measure the pressure above the cargo and provide a warni ng should pre-set over pressure or under pressure settings be exceeded; Temperature monitoring sensors which measure the temperature of the cargo at different levels in the tank and provide the i nformation to a remote display; and Gas sensors (which are fitted on some tanks) automatically measure the oxygen content and the concentrations of selected gases within the space and provide the information to a remote display. Pump stack valve

Figure 5.2 - Tank Equipment and Instrumentation

5.3.2

ALARMS AND SHUTDOWNS An important feature of modern measurement and control instrumentation is the ability to provide a constant readout of, for example, the level of the product in the tank, the tern perature of the product and the composition and pressure of the atmosphere i n the ullage space above the cargo. A further advantage is that alarms can be set so as to warn the crew should pre-set conditions be exceeded, such as when the liquid level in a tank reaches a certain level. In some cases alarms trigger an action such as shutting down a pump or other device so as to avoid a hazardous situation developi ng. Some monitoring equipment is also capable of monitoring its own performance_ Should the equipment malfunction an alarm is raised, indicating a failure within a sensor's own operating mechanism. The designs and purposes of alarm and shutdown circuits vary widely. Their operating system may be pneumatic, hydraulic or electronic. The following precautions should be observed: Where provided, test facilities for alarms and shutdown systems should be checked before cargo operations commence, to ensure that they are operating correctly. If the sh ip is at sea, this will allow time to rectify any faults prior to arrival;

93

Watchkeepers should be familiar with each alarm and the correct action to take when an alarm is activated; When an alarm is activated, the cause must be assessed and the necessary remedial action taken; and

If a defective alarm cannot be repaired immediately and alternative measures to monitor the operation are unavailable, the operation should be stopped. A decision to continue should be considered as a non-routine operation and be subject to a risk assessment.

5.3.3

AIR SUPPLY TO CONTROL SYSTEMS The performance of instruments and control systems that depend upon a supply of clean, dry air can be degraded quickly if the air supply is contaminated or interrupted. Water is a common contaminant which can give rise to corrosion and equipment malfunction. The presence of lubricating oil can also cause problems. The air supply should be leak free while filters and dryers should be checked and drained frequently.

5.3.4

LIQUID LEVEL GAUGES During all gauging. appropriate PPE should always be worn.

General To limit the crew's exposure to harmful ch emicals, Chapter 13 of the IBC Code specifies three methods of gauging the level of a liquid i n a tank, namely closed, restricted or open. The particular requirements for gauging specific cargoes can be found in Chapter 17 of the IBC Code. Most closed gauging systems are also provided with alarms which warn the crew when the tank is neari ng its maximum capacity. As required by the !BC Code, many chemical cargoes should only be gauged using completely closed gauging systems. This is in order to avoid exposing the crew to cargo vapours. Examples of closed gauging systems include some float gauges and gauges that utilise radar or differential pressure systems. Chemicals considered less hazardous do not require quite such rigorous controls, and the specified restricted gauging accepts that a very small amount of vapour may escape during gauging.

Open

Open

Restricted

Closed

Figure 5.3 - Gaugi ng Types Where permitted, open gauging allows non-hazardous cargoes to be gauged through tank openings using manual measuring equipment. SOLAS requires tankers fitted with fixed inert gas systems to be provided with a closed gauging system.

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TANKER SAFETY GUIDE (CHEM,CALS)

Float gauges These are commonly closed gauges, and consist of a float which is attached by a self-tensioning tape to a device with a local read out, and frequently having provision for a remote read out. As the liquid in the tank rises or falls the tape measures the distance between the float and the datum set at the top of the tank (ullage). Float gauges, especially the tape, are easily damaged and the following precautions should be observed: Floats should be secured when at sea, except briefly during measurement of tank contents. If the float remai ns unsecured at sea it will almost certai nly be damaged due to sloshing of the cargo; Remote and local readings should be compared frequently to determi ne any discrepancies; Readings may need to be corrected to allow for tape and tank expansion or contraction, cargo density and ship trim and heel; Tapes should be checked regularly for free vertical movement of the float, and if damaged, they should be replaced; When tapes are renewed, or a gauge reassembled after maintenance, they should be recalibrated to ensure correct measurement between the cargo and the required tank datum. Manufacturers' instructions should be consulted; and During tank cleaning the float should be locked in the raised position to avoid damage to the tape by high pressure washing water. Other designs of gauges use floats that rise and fall on the outside of a closed pipe which penetrates the main deck. Inside the pipe are fixed magnets and a series of svvitches that transmit a signal to a display unit, usually in the cargo control room.

Manual gauging systems These systems use a probe at the end of a tape to check the level of cargo in a tank. The measuring probe is lowered into the tank via a small diameter pipe fitted with a ball valve at deck level. On contact vvith the surface of the liquid an audible signal is generated and the ullage in the tank is displayed. Most probes of this type can also measure the temperature of th e product as well as the oil/water i nterface, when the probe is lowered further i nto the liquid. The body of the unit is gas-tight when secured by the valve on the pipe on deck thereby providing an effective vapour lock. Vessels are frequently provided with a number of these units as a back up to the primary gauging system.

Figure 5.4 - Manual Closed Gauging System (Restricted Gauging)

95

Radar. ultrasonic or microwave gauges These are also closed gauges, and work on the principle used in radar or echo sounders. Pulses are transmitted from the top of the tank and the time taken for them to be reflected back is measured and displayed as an ullage or sounding. Special arrangements may be made during construction to reduce interference by the internal tank structure. Radar gauges are generally reliable, and most maintenance can be performed from outside the tank, with the tank in the closed condition. Pressure sensing gauges Pressure gauges utilise the difference between atmospheric pressure and the pressure the liquid exerts near the tank bottom. This sensor therefore provides the weight of the cargo in the tank. In order to obtain the volume, further calculations are required using knowledge of the cargo density and its temperature. In some systems, additional sensors are provided to enable the density to be automatically measured and applied.

5.3.5

OVERFILL DETECTION SYSTEMS High l evel alarms Certain cargoes require tanks to be fitted with high level alarms which are independent of any alarms fitted to the closed gauging system. The alarm may be activated by either a float operated switch, a capacitive pressure transmitter, or an ultrasonic device. The activation point should be set to when the cargo is approaching the normal full condition. Typically this limit w ill be set at 95%.

Figure 5.5 - Tank Alarms Tank overflow control systems (high-high l evel alarms) Tank overtlow control systems should be set to alarm when the level in the tank reaches 98% of capacity. Testing alarms All high level and overflow alarms should be tested in accordance with the manufacturers' instructions to ensure correct operation prior to cargo operations. This will ensure that the alarms are working correctly and can be relied upon.

5.3.6

PRESSURE INDICATING DEVICES General Pressure gauges are fitted at various points in the cargo system, on pumps, in pipelines and in tanks. They may be used to indicate pressure in a liquid being pumped into or out of a tank, or static pressure such as that of inert gas. They can indicate negative as well as positive pressure, and can be linked to shutdown or alarm systems.

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TANKER SAFETY GUIDE (CHEMiCAL5)

It is important that procedures exist for ensuring that pressure gauges are checked and calibrated in accordance with manufacturers' instructions. Bourdon type pressure gauges These instruments measure pressure by the movement of a coiled or helical tube, the movement being directly proportional to the applied pressure. The following precautions should be observed: The indicator should be periodically checked for zero calibration; The gauge should not be used consistently to indicate pressures beyond 75% of its maximum reading if the expected pressure is steady, or 60% if it is fluctuating; and Bourdon tubes may be damaged by vibration or by excessive pressure pulsations. The latter can be eliminated by the use of a flow restrictor. Capacitive pressure transmitters Pressure in vapour spaces of cargo tanks (and elsewhere) can be monitored by measuring the effect of the existing pressure on sealed units that have a known internal pressure. Deflection of the sealed unit is proportional to the pressure exerted and is measured by an internal capacitor, which sends an electronic signal to a remote display. An external measurement of atmospheric pressure is necessary for the display to show gauge pressure. Alarm levels can be set as necessary. General precautions The following precautions apply to all pressure sensing equipment: Materials of construction should be compatible with the cargo. The IBC Code identifies cargoes where special attention must be paid to materials of construction; Pressure gauges should not be subjected to violent pressure changes; When carrying cargoes which can solidify or form polymers it may be necessary to flush pressure gauge lines and sensor chambers; and Sensor lines that are temporarily disconnected during maintenance should be blanked.

5.3.7

TEMPERATURE MONITORING EQUIPMENT Sensors are fitted so that the temperature of the cargo can be monitored in order to: Ensure that cargo heating requirements are complied with; Ensure that any tank structure and tank coating temperature limitations are not exceeded; and Calculate the weight of cargo on board (the specific gravity of a product varies according to temperature). Sensors may also be fitted to monitor the temperatures of the structure around the cargo system. Types of thermometers Liquid/vapour thermometers rely on the expansion or contraction of liquid in a very fine bore calibrated t ube or capillary. It is important to ensure that the liquid column in the instrument is continuous, otherwise the reading will be inaccurate. Bi-metallic thermometers consist of two metals with different coefficients of expansion. Bi-metallic thermometers are susceptible to vibration and should only be installed in positions that are free from this effect. Thermocouples rely on heat applied to the junction of two dissimilar metals generating a very small voltage which can be measured. A change in voltage output will indicate a change in temperature.

97

General precautions The following precautions sh ould be observed with all temperature i ndicating dev'ices: The thermometers u sed should be suitable for the complete range of temperatures expected; and The sensor should make good thermal contact with the material whose temperature is to be measured.

5.4

ATMOSPHERE MONITORING

5.4.1

GENERAL In order to monitor the atmosphere within enclosed spaces, especially prior to tank en try, several different gas measuring i nstruments are required. In addition to any fixed gas detection system, at least two of the following portable i nstruments sh ould be available on board: Oxygen analysers capable of measuring the percentage volume of oxygen; Flammable gas i ndicators capable of measuri ng the Lower Flammable Limit (Ufl) of the atmosph ere; and Toxic gas i ndicators capable of measuri ng the presence of a specific toxic gas to establish the risk to personnel.

5.4.2 GENERAL PRECAUTIONS Usi ng atmosphere monitoring equipment requires care in order to en sure that the readings are accurate, especially when the lives of personnel depend upon them . The following precautions should be observed : The user should be familiar w ith the limitations and correct use of the i nstrument ; The manufacturer's instructions should be followed; The instrumen t should be calibrated at intervals in accordance with the manufacturer's instructions and, where applicable, in compliance with company procedures; Records of testi ng, calibration and any mai ntenance carried out should be kept and be available to the user; Before use the instrument should be ch ecked and tested in accordance with the manufacturer's instructions; Span gas, 15 which might be flammable and/or toxic, should be handled with care. It should be ensured that the specification of the span gas matches that stipulated by the m anufacturer; All sample lines should be clean, unobstructed, leak free and connected to the correct point. Sample lines should o nly be used with the instrument for which they are designed; All sample lines sh ould be made of the correct material as specified by the manufacturer. Incorrect tubing may absorb gas from the sample and cause inaccurate readings; For fixed instruments, remote and local read outs should be compared to detect any discrepancies; The performance of most fixed instruments depends on an adequate flow rate, and fl uctuations can cause inaccuracy; tS Span gases are special gas mixtures used for testing gas detection equipment. Calibtation is important for all such testing instruments and is done by means of e>q::iosing the sensor to a known concentration of a contaminant (span gas). The gases. are used as a reference point to ensure corr'ect readings after calibration.

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TANKER SAFETY GUIDE (CHEMICALS)

The battery voltage of portable instruments should be checked; and Damage to the instruments by water, steam, other contaminants and mechanical damage should be guarded against. Particular care should be taken during tank cleaning.

5.4.3

OXYGEN ANALYSERS General Oxygen analysers are used to determine the oxygen level in an atmosphere. The use of oxygen analysers for checking the atmosphere before entry to enclosed spaces is described in Chapter 9. Level of oxygen in air Throughout this Guide the percentage of oxygen in air is referred to as 21 % . However, the percentage of oxygen in air falls several hundredths of a percent below this figure, variously quoted as being between 20.85% and 20.95% . Modern instrumentation with digital indicators can measure so accurately that the full 21 % may be impossible to obtain. If an instrument capable of such accuracy is in use, the manufacturers' instructions should be carefully read and understood, so that the readings can be properly interpreted. El ectrochemical analysers Analysers of this type measure the output of an electrolytic cell that is exposed to a sample of the atmosphere being tested. The current flow is related to the oxygen concentration in the sample, and the scale is arranged to give a direct indication of the oxygen content. Analysers working on this principle can also be used to measure the concentration of various gases found on board ship such as carbon monoxide, carbon dioxide and hydrogen sulphide. The analyser's sensors can be damaged in the presence of certain gases such as sulphur dioxide and oxides of nitrogen found in inert gas. These instruments are therefore unsuitable for measuring the oxygen content in tanks which have been inerted with flue gas or the output of an inert gas generator. Paramagnetic analysers Paramagnetic instruments measure the deflection of a magnet pivoted within a symmetrical non-uniform magnetic field. The magnet is suspended in a chamber into which the gas sample is introduced and the deflection is directly proportional to the oxygen concentration. These instruments can be used for detecting oxygen in mixtures of other vapours. It should be noted that some other gases, notably oxides of nitrogen, have comparable paramagnetic properties to oxygen. This technique cannot therefore be used if such other gases are present in more than trace amounts. Selective chemical liquid absorption analysers In liquid absorption instruments a known volume of the atmosphere to be sampled is passed through a liquid which absorbs the oxygen, causing a volume change in the liquid. The final volume is measured on a scale which indicates the oxygen content of the original sample gas.

It is essential to use the correct type of oxygen analyser for the atmosphere being tested.

Personal oxygen analysers Small analysers are capable of continuously measuring the oxygen content of the atmosphere. They can be attached to clothing or sometimes are supplied attached to an armband. They should provide an audible and visual alarm when the atmosphere becomes deficient in oxygen, so as to give the wearer adequate warning of unsafe conditions.

5.4.4

FLAMMABLE GAS DETECTORS General Flammable gas detectors measure the presence of flammable vapours in order to assess the risk of fire and explosion. There are several types of flammable gas detectors which differ according to their method of operation. Combustion type A sample of gas is drawn by a pump into the instrument via a tube lowered into the space to be tested. The sample of gas is drawn into a combustion chamber within the unit, suitably protected by a flash back arrester, and then passes between two elements. When no gas is present the resistance of the two elements is in balance. When a flammable gas is present it will cause the temperature of one element to rise, and this effect can be measured and the flammability of the gas expressed as a percentage of the Lower Flammable Limit (LFL). The elements can easily be deactivated by materials such as silicones, halogenated gases, acids, water, oil and lead. Filters may therefore be required in the sample lines to protect the elements from contamination. The equipment needs a minimum of 11 % oxygen to operate, and therefore cannot detect combustible gases within an inerted atmosphere. If a mixture of inert gas and cargo vapour has to be tested, either an infra-red or thermal conductivity meter must be used.

Combustion type detectors cannot be used to measure the flammability of gas within an inerted space.

Thermal conductivity type These instruments work by measuring the thermal conductivity of hydrocarbon gas in the atmosphere being tested. The instrument can be set to measure the presence of hydrocarbon gas in air or in an inerted atmosphere. As a sample from the space is drawn into the instrument the presence of hydrocarbon gas will alter the resistance of the sensor. This will be expressed as a percentage by volume of the amount of hydrocarbon present in the sample. The sensor may either be mounted so that the sampled gas flows directly over it or diffuses into it. The direct flow type responds more quickly to concentration changes but is dependent on flow rates. The diffusion type gives a slower response but is less flow rate sensitive. Thermal conductivity meters are pressure sensitive and any difference in pressure between the tank being measured and the atmosphere will lead to inaccuracies. The manufacturer's instructions should always be followed in order to avoid such errors. Refractive index detector type This type of detector utilises the principle of comparing the difference between the various refractive properties of different gases. This equipment can only be used to measure the type of gas for which it is designed. In order to function when testing for gas within an inerted atmosphere appropriate absorbent filters have to be used. Infra-red detector type An infra-red detector determines the concentration of hydrocarbon vapours by measuring the ability of gases to absorb infra-red light.

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5.4.5

TOXIC GAS DETECTORS General A common method of detecting the presence of toxic vapours in a space is to use equipment specifically designed to measure the concentrations of the last product carried in the space. When toxic vapour detection equipment is not available for products that require such detection, the IBC Code advises that flag administrations may permit tank entry subject to the provision of additional BA equipment and a record being made in the International Certificate of Fitness regarding the particular product. See also Chapter 9. Chemical detector tubes These instruments work by drawing a sample of the atmosphere to be tested through a proprietary chemical reagent in a glass tube specifically designed to measure the product being tested. The detecting reagent becomes progressively discoloured in proportion to the amount of toxic vapour present in the sample. The length of the discoloration stain provides a measure of the concentration of the chemical vapour which can be read from the graduated scale printed on the tube. Detector tubes give an accurate indication of chemical vapour concentration, whatever the oxygen content of the mixture. It is important that the correct volume of the vapour to be tested is drawn through the tube, otherwise the measurement w ill not be accurate. The length of hose is a critical factor in obtaining a correct reading. The presence of a second gas may affect readings and cause inaccuracies. The storage life of the tubes is limited, and it is necessary to ensure that out of date tubes do not remain available for use.

Equipment from different detector tube manufacturers should not be combined in a testing system.

PIO Detectors Photo ionization detectors (PIOs) measure volatile organic compounds (VOCs) and other gases in minute concentrations. The PIO is an efficient and relatively inexpensive detector that may produce instantaneous readings and can be operated continuously. PIOs may be used for monitoring the Lower Flammable Limit (Lfl) of atmospheres including the presence of low levels of contaminants. However, the detection of particular products requires specific calibration. Other atmosphere tests, including for sufficient oxygen levels, should be carried out before confirming a space as being safe to enter. FID Detectors A flame ionization detector (FIO) is a type of gas detector originally developed for use in gas chromatography. FIOs are effective for detecting hydrocarbons, and have a response that tends to be linear across a wide range of concentrations.

101

The following table summarises the ch aracteristics of different atmosphere monitoring instrumen ts, their purpose and limitations: DETECTION TYPE

OPERATING PRINCIPLES

COMMENTS

TYPICAL USE

INFRA-RED

Hydrocarbon gas absorbs infra-red radiation.

Detects 0-100%

Primarily fixed gas detection systems.

Comparison of sample against reference gas of known concentration.

Where device reports in LFL it sh ould be noted that oxygen is required for a tru e LFL measurement.

Changes in sensi ng filament temperature i n presence of hydrocarbon gas results in a change of resistance.

Detects 0-1 00% hydrocarbon vapour by volume.

THERMAL CONDUCTIVITY

hydrocarbon vapour by volume.

Portable units available. Not suitable for high concentrations of petrochemical gases. Portable unit to detect hydrocarbon vapour e.g. when i nerti ng.

May be u sed in presence of inert gas. Should be calibrated to suit gas being tested.

COMBUSTIBLE GAS

Changes in sensi ng filament resistance

Detects % LEL usually 0- 100% LEL.

Pre-en try checks of enclosed spaces.

i n presence of hydrocarbon gas.

Requi res oxygen to operate.

Fixed gas detection systems.

Not suitable for u se if inert gas is present. CHEMICAL ABSORPTION e.g. Detector tubes

Discolouration of ch emical reagent i n presence of specific gas.

Detects specified gases. May be u sed in the presence of inert gas.

Possible detection of ve·ry low concentrations of speci fied gases.

Limited shelf life. OXYGEN ANALYSERS

Technology used i ncludes e.g.:

Detects percen tage of oxygen by vol ume.

Pre-en try checks of enclosed spaces.

- Paramagnetic sensor

An alysers for personal use provide co ntinuous monitoring of atmosphere.

Monitoring progress of aeration and inerting operations.

Ultra-violet light

Detects ppm of VOC

Personal monitors for

u sed to ionize gas molecules.

vapour.

use during tank entry.

- Chemical absorption - Liquid absorption - Semi-permeable membrane. PHOTO IONIZATION (PIO)

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TANKER SAFETY GUIDE (CHEM,CALS)

M ulti-gas sen sors are available.

DETECTION TYPE

OPERATING PRINCIPLES

COMMENTS

TYPICAL USE

FLAME IONIZATION (FID)

Detection of ions formed during combustion of organic compounds in a hydrogen flame.

Mainly used in gas chromatographs.

Land based laboratories.

PERSONAL GAS MONITORS

Typically use absorption and electrochemical

Continuous monitoring of atmosphere with

Entry into enclosed spaces.

sensors.

built-in alarm functions if atmosphere becoming unsafe.

5.5

CARGO PUMPS

5.5.1

GENERAL

Working in potentially hazardous atmospheres e.g. manifold when connecting/ disconnecting.

There are two main types of cargo pump utilised on chemical tankers: The most common are centrifugal deepwell pumps, where an individual pump is installed in each cargo tank; and For heavier and more viscous cargoes screw pumps are used, which can be of a deepwell design or more often they are installed in a pumproom. Pumps sited in pumprooms are usually found on ships dedicated to a particular trade.

5.5.2

DEEPWELL PUMPS A deepwell pump is located in a recess located in a position in the tank to achieve best possible stripping. Power is either provided by a hydraulic motor or an electric motor. Hydraulically powered deepwell pumps have a hydraulic motor, which is located within the tank. The hydraulic supply and return lines are enclosed within a double walled cofferdam so that in the event of a hydraulic leak the cargo will not be contaminated. The cofferdam also prevents contamination of the hydraulic oil by the cargo. The pump's cofferdam should be purged regularly in order to allow checking for any signs of leakage past the shaft seals that protect the cofferdam.

103

Figure 5.6 - Deepwell Pump

Electrically powered deepwell pumps have the motor mounted on deck. It is connected to the pump by either a drive shaft enclosed in an oil filled tube surrounding the shaft, or else the drive shaft is located within the discharge line and is cooled and lubricated by the cargo.

5.5.3

CARGO PUMPROOMS Some chemical carriers are built with cargo pumps sited in cargo pumprooms. Various power options and pump designs can be utilised and the pumps and the piping systems can be designed to serve either single tanks or a combination of tank groups. Vessels fitted with cargo pumprooms are required by the IBC Code to: Have adequate mechanical ventilation; Be provided with bilge high level alarms; Have continuous fire detection and a fixed fire extinguishing system provided; Have a means of evacuating a casualty from the lower platform level; and Be provided with an alarm should a crew member get into difficulties while working in the pumproom.

5.5.4

BOOSTER PUMPS Some vessels are provided with booster pumps which can be used in series to improve the pumping performance of the vessel's cargo pumps when discharging viscous products or large volumes of a single cargo.

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5.5.5

EMERGENCY CARGO PUMPS Ships fitted with deepwell pumps are normally provided with an emergency cargo pump as there is no immediate possibility of repairing the primary pump should it fail. Portable emergency pumps are hydraulically driven and are lowered into th e tank via the tank h atch. The emergency pump is com pletely self-contained and provided with its own hydraulic hoses and disch arge hose sufficient in length so that the pump can be lowered to the bottom of the tank. The use of an emergency cargo pump should always be considered as a non-routine operation and a risk assessment should be conducted prior to its use. Permission should also be requested from the terminal and the port authorities who may i mpose particular requirements.

5.6

PIPING SYSTEMS AND VALVES The pipi ng system of a chemical carrier is designed to ensure positive segregation between different grades of cargo and to provide for operational flexibility. Pipelines are usually made of stainless steel. There are three main types of valves used w ithin the cargo pipeline system. Ball valves have the best sealing arrangement and are easy to operate:

Valve open

Valve closed

Valve open

Valve closed

Figure 5. 7 - Ball Valve

Gate or sluice valves have a good sealing arrangement but take ti me to open and close:

Valve open

Valve closed

Valve partially OPE
Valve closed

Figure 5.8 - Gate Valve

105

Butterfly valves are quick to operate but are prone to leak if the seals are not well maintained:

Valve open

Valve closed

valve partlally open

Valve closed

Figure 5.9 - Butterfly Valve

5.7

CARGO MANIFOLD The cargo pipelines for each tank or group of tanks lead to the manifold which is usually sited in the mid-part of the vessel. The manifold lines, which should be labelled to aid identification, run athwartships so that connections can be made either side. Each line is equipped with a manifold valve at the point of connection to the shore system .

•

-- -.!.~---

Figure 5.10- Cargo Manifold In addition to the cargo line connections, the following equipment and systems are also available at the manifold. Common line When handling homogeneous cargoes the shore connection is usually a large capacity hose or loading arm . This is often impracticable to connect to the vessel's normal manifold system so a larger common pipeline arrangement is provided whereby all the vessel's cargo lines are joined to a larger capacity line. The common line's connection point is situated so that large capacity shore lines can be connected safely and without putting undue strain onto the ship's equipment. This arrangement is provided with a full range of isolation valves or blanking arrangements so as to ensure that full flexibility is maintained. The vessel 's booster pumps, when fitted, are usually connected directly to the common line.

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Stripping l i nes Connections are provided at the manifold to operate the vessel's stripping system. In addition to the stripping system, valves are provided to allow both the ship's lines and the shore lines to be cleared by blowing nitrogen o r compressed air on completion of cargo operations. Sampling Sampling points are provided at the manifold i n order that sampling of products can be taken at the point of transfer between the vessel and the shore. Vapour return Vapour return connections are provided close to the manifold.

Drip tray A drip tray has to be fitted under the manifold area for the retention of any leakage at the ship/shore connection and must be provided with a means of emptying collected residues.

5.8

VENTING SYSTEMS AND P/V VALVES Tank vent system outlets are required by the IBC Code to be located at a safe distance from areas where personnel may be present. A pressureiliacuum (PN) valve is designed to protect a tank from <:Ne< or unde< pressure during loading and discharging. The PN valve also protects the tank from changes i n pressure duri ng the sea voyage and protects the cargo from direct contact with the atmosphere. Should an under pressure develop in the tank, for example when discharging, the vacuum side of the PN valve opens and allows air to enter the tank. When loading, pressure will build up i n the vapour space above the cargo and, once the predetermined limit is reached, th e PN valve's pressure side opens relievi ng the pressure. The valves are designed so th at when they lift under pressure the vapour is ejected vertically and well clear of the working deck. Chemical carriers are provided with an independent PN valve for each tank. The PN valves are designed to handle vapour flow based on the maximum loading or disch arge rate of the tank. The vent line should be self-draini ng where possible. IMO regulations require that a secondaiy means of protecting cargo tanks against <:Ner or under pressure must be available should the primaiy means of venting fail. This can be complied with by fitting an extra PN valve and vent line or alternatively by fitting a pressure sensor in the tank (see Section 6.4.5).

Figure 5.11 - Pressure/Vacuum (P/V) Valves

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A venting system that fails to function can lead to an excessive build up of pressure or vacuum in a tank, resulting in major structural damage.

5.9

VAPOUR RETURN SYSTEMS The purpose of vapour return systems is to ensure that cargo vapours are not released to the atmosphere. Vapour return lines on chemical tankers are either connected to the vessel's PN line or, if the vessel is fitted with an inert gas system, to an extension of that system. The vapour return lines are led to the manifold where a connection is provided to connect to the shore vapour collecting line. As the tank is loaded the shore recovers the displaced gas from the tank being loaded where it is stored, treated or disposed of under controlled conditions. The vapour return system is intended to maintain a slight over pressure in the cargo tank(s) which is below the pressure setting of the tank's PNvalve. In certain circumstances, the vessel is required to accept cargo vapours from shore while the ship is discharging, although the operating principle remains the same. In order to ensure that the balance of gas between ship and shore is maintained within safe limits, over and under pressure sensors are provided on the ship's vapour return line to provide a warning should the operational limits be exceeded. The tank's PN valve remains the essential safety device should the pressure or vacuum in the tank exceed the designed set levels. The IBC Code requires the ship to be able to return vapours of most toxic chemicals to shore.

Figure 5.12 -Vapour Return Manifold Connection of hoses intended for vapour transfer to manifold flanges of pipelines for liquid transfer is prevented by a stud permanently fixed between two bolt holes in the presentation flange of the ship's vapour return manifold. The stud will fit into a corresponding additional hole in the flange of the shore vapour hose. The stud is designed to avoid a cargo liquid hose being connected to a vapour connection by mistake. Unfortunately, not all terminals have vapour connection hoses provided with a corresponding hole in the connecting flange. Vapour connections should therefore also be identified by painting and stencilling in a standard way.

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,-----1

I I..-__]_ 500 ~1

I' I I I

~:

I I

I 800 ---~

:.,..._

yellow

I I

~:

:.,..._

100

100

red

red

16m m dia. hole in the inboard end of reducer and in hose flange to accept stud 12.7mm dia . stud at 12 o'clock on presentation flange

L

~~

'VAPOUR' to be stencilled on side at 10 o'dock and 2 o'clock

All dimensions in millimetres

Figure 5.13 - Vapour Manifold Presentation Flanges. Orientation and Labelling

5.10 HEATING AND COOLING SYSTEMS Most chemical tankers are provided with systems to heat or cool the cargo. There are two main methods employed to control the temperat ure of a cargo: heating coils and heat exchangers. Heating coils These consist of a continuous rack of small bore pipe, made of stainless steel, which is laid to cover the bottom of the tank. The coils are mounted about 10cm above the tank top and are secured by brackets. The heating medium is circulated through the coils, under pressure when steam is used, or by a pump when an alternative heating medium is used . Heat exchangers This system utilises the deepwell cargo pump to circulate the cargo via a heat exchanger mounted on deck and returned to the tank via a drop line mounted at the opposite end of the tank from the cargo pump.

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Heating medium The following media can be used for heating: Steam is efficient but is difficult to control and has a high contact temperature; Water is less efficient than steam but provides a more accurate temperature control; and Thermal oil is utilised where the cargo may react with water.

Cooling systems Some chemical tankers are equipped with a system that can circulate a cooling medium in order to keep the cargoes below a specified temperature. The coolant is usually circulated via the same coils that are used when heating a cargo. Typically chemical tanker cooling systems are only designed to prevent the cargo from heating in warmer ambient conditions and cannot maintain or cool a cargo below 1 C.

s·

The IBC Code requires cooling capacity for a number of cargoes that have a high vapour pressure and thus might start to boil if ambient conditions allow the cargo to h eat.

5.11

TANK WASHING SYSTEMS There are many variations of tank cleani ng equipment but they all work on the same basic principle whereby a tank cleaning machine directs jets of water, under pressure, against the tank's internal surfaces. The nozzles of the tank cleaning machine slowly rotate, both vertically and horizontally, so that all surface areas of the tank are covered.

5.11.1

FIXED TANK WASHING MACHINES The installation of fixed tank washing machines within a cargo tank allows cleaning in a closed mode minimising the release of noxious vapours. Fixed tank washi ng systems often have an option to modify the washing cycle. Fixed tank cleani ng systems are permanently bonded to the ship's structure.

Figure 5.14 - Fixed Tank Washing Machine

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5.11.2 PORTABLE TANK WASHING MACHINES AND HOSES Portable machines are made of non-spark inducing materials. Portable machines are connected to the ship's tank cleaning system by means of hoses. The advantage of portable machi nes is that they can be placed at various levels throughout the wash cycle. When cleani ng after particularly difficult cargoes such as vegetable oils, the machines can be positioned where they can work more effectively to cover shadow areas where permanently fixed machines may not reach. In order to ensure electrical conti nuity, bonding wires should be incorporated within all tank cleaning equipment so as to en sure th at the tank cleani ng machine is securely bonded to the ship's structure. Hoses sh ould be tested for electrical continuity i n a dry condition prior to use, and in no case should the resistance exceed 6 ohms per metre length. A record sh ould be kept of each hose showing the date and result of electrical continuity testi ng. If ropes are used to suspend the portable machines, they should be made of natural fibre to prevent the gen eration of static. Further information o n electrostatic precautions during tank washing is provided in Chapters 1 and 8.

5.12 GAS FREEING EQUIPMENT Gas freei ng requi res large volumes of air to be safely forced i nto the tank i n order to remove hazardous vapours. It is recommen ded that there is no penmanent connection between the gas freeing line and the cargo system lines.

5.12.1 PERMANENTLY INSTALLED GAS FREEING EQUIPMENT Where cargo tanks are gas freed by means of permanently i nstalled fans, air is introduced into the cargo tank through either the cargo lines, the inert gas lines, or via ducting to a gas freei ng hatch. Permanently installed gas freeing fans can be provided with a heati ng o r dehumidifying system to sp eed up tank dryi ng processes.

5.12.2 PORTABLE GAS FREEING EQUIPMENT Portable fans are w ater, steam, hydraulically or pneumatically driven. Thei r construction materials sh ould be such that no sparks are generated sh ould the blades of the fan come into contact with the fan casing. Guards should be in place to prevent accidental co ntact w ith fan blades. Prior to starting, portable fans sh ould be connected to the ship's structure to en sure th at an electrical bond exists (see Section 8.10.1).

5.12.3 VENTING OUTLETS The IBC Code requi res vessels to be provided with gas freeing outlets that ensure that, when gas freeing, the vapour is displaced at sufficien t velocity to carry the vapours clear of the deck.

ll1

Figure 5.15-cargo Tank Vents

5.13 INERT GAS SYSTEMS 5.13.1 INTRODUCTION On board chemical tankers inert gas (IG) systems can be used for: Preventing fire and explosion by maintaining the atmosphere in the tank below the LEL; Preventing a chemical reaction . The IBC Code specifies that certain products must be transported under an inert atmosphere; and Maintaining cargo quality. Flammable gases normally encountered in chemical carriers cannot burn in an atmosphere which is deficient in oxygen. An atmosphere that cannot support combustion is said to be inert. In o rder to create a non-combustible atmosphere in a tank an inert gas is used to displace the air in the tank.

5.13.2 OXYGEN CONTENT The fire hazard presented by a cargo stowed in a cargo tank is dependent on the flammability of the product and the oxygen content of the atmosphere above it. By filling the ullage space in a cargo tank with an inert gas such as nitrogen or an inert gas produced by a combustion process, the oxygen content can be reduced to a level at w hich the atmosphere will no longer support the combustion of a flammable vapour.

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The minimum oxygen concentration (MOC) is defined as the mini mum concentration of oxygen below which combustion is not possible, regardless of the concentration of flammable vapour presen t. For most hydrocarbons, the MOC varies between 10.5% and 12.0%. The MOC is further depen dent on temperature, pressure and the type of inert gas. SOLAS regulations require an i nert atmosph ere to be maintained with a maximum oxygen content of 8%, although some ch emical cargoes will need a low er oxygen content to be mai ntained (see Section 4.5). An inerted atmosphere will become flammable again if air is admitted. It is therefore essent ial th at the tank remains fully closed. Natural breathi ng of the tank through the vent system will i ntroduce air into the tank during th e voyage. It is therefore i mportant that the oxygen level is regularly checked and the tank topped up w ith IG as necessary. SOLAS specifies that the maxi mum quantity of oxygen allow ed to en sure effective inerti ng of a tank is 8%. The regulations also describe the equipment and co ntrol devices necessary to ensure a safe operation. Not all chemical tankers are fitted w ith inerting capability but an increasing number of ships are provided w ith inert gas systems, usually nitrogen .

5.13.3 SOURCES OF INERT GAS There are several sources of inert gas available to a chemical tanker: Stored compressed nitrogen; Stored liquid nitrogen; Nitrogen gen erators usi ng pressure swing adsorption (PSA); Nitrogen gen erators usi ng membrane separation; Nitrogen supplied from sh ore; and Oil fired inert gas gen erators. Nitrogen Nitrogen is the preferred inert gas for use on board chemical tankers. It is clean and relat ively cheap to produce o n board or can b e supplied from the shore. In addition to preventing fires, nitrogen also helps protect cargoes from water absorption and may also be specified for other quality control reasons. As from 1 January 2016, ships using inert gas in compliance with n ew SOLAS Regulation 16.3.3 (see Section 4.5) must only use nitrogen for inerting their tanks. Inert gas from a combustion process Inert gas produced from combustion, u sually of gas oil, is cheap and effective. However, the inert gas produced has many impurities. The gas must be cooled and scrubbed with w ater to remove soot and sulphur acids before bei ng supplied to the cargo tanks. Some cargoes react wit h carbon dioxide in fl ue gases. Other cargoes are highly sensit ive to moisture, or are liable to discoloration. As the scrubbing process does n ot effectively remove all con tami nants or prevent the carryover of moisture, oil fired inert gas systems are rarely u sed o n chemical carriers.

5.13.4 COMPRESSED NITROGEN STORED ON BOARD High pressure gaseous nitrogen can be stored in steel cylinders. The common size is 50 litres capacity, pressurised to 200 bar, which will supply 1Orn' of gaseous nitrogen. It can be used to compensate for normal transportation losses of IG and to maintai n the requi red over pressure. A typical installation o n a ship consists of a number of such cylinders connected in parallel to form a battery, w hich uses a pressure regulator that is set to mai ntain th e required positive pressure in the cargo tanks w ithout lifting the tank pressure relief valve. Compressed nitrogen can b e obtained in several grades of purity.

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5.13.5 LIQUID NITROGEN STORED ON BOARD Nitrogen can be stored on board in liquid form, at the cryogenic temperature of - 196•C. It is stored in i nsulated tanks made from cold resistant material, usually stainless steel pressure vessels. The cryogenic tank has an inner and outer casi ng, the space between these is filled with insulation and maintained under vacuum. This allows nitrogen to be stored over extended periods without appreciable loss. Liquid nitrogen storage tanks fitted on chemical carriers are refilled in port from shore resources. When gaseous nitrogen is required for use in cargo tanks, the liquid is converted back to gas using a finned tube evaporator that obtains the necessary heat for vaporisation from the ambient air.

5.13.6 PRESSURE SWING ADSORPTION (PSA) NITROGEN GENERATORS Adsorption is a process in which a substance, usually a gas, accumulates on the surface of a solid to form a very thin film. Pressure swing adsorption (PSA) plants work on the principle that the major constituents of air (nitrogen and oxygen) are adsorbed to a different extent when passed over a carbon-molecular sieve material. The amount of each gas adsorbed depends on the time of exposure. If the system is adjusted correctly, the sieve adsorbs most of the oxygen i n the air, allowing the nitrogen to pass through and be collected. The oxygen can then be desorbed (returned to a gas) and exhausted to atmosphere, thereby regenerating the sieve. To give a continuous nitrogen flow, PSA plants are fitted with two or more i nterconnected pressurised vessels (called beds) which contai n the molecular sieve material. Air is compressed by an oil free compressor and passed over one set of beds that are adsorbing, while the oth er set of beds is desorbing. During the production cycle, therefore, the plant will vent an oxygen rich waste, which must be exh austed to a safe area. A number of proprietary sieve materials are water sensitive, and the compressed air must be passed through a dryer to remove most of the atmospheric humidity before passing over the beds. The air inlet to the PSA beds must always be protected from spray. The gas produced by the PSA process may have an oxygen content varying between 0.1 % and 5% by volume depending on the flow rate.

5.13.7 MEMBRANE SEPARATION NITROGEN GENERATORS Membrane unit s are based on the fact that different gases permeate at different rates through the walls of a thin, hollow membrane. Gases that permeate at different rates are categorised as being 'slow', ' medium' or 'quick' gases. The 'slow' gases are methane, nitrogen and carbon monoxide, the 'medium' gases are argon and oxygen, and the 'fast' gases are water vapour, hydrogen and carbon dioxide. The fact that the two main components of air, nitrogen and oxygen, have different permeation rates means they can be separated. The fact that water vapour permeates quickly means that th e nitrogen produced is also very dry. The mem brane unit is made up from bundles of thin hollow fibres which provide a large surface area for separation. The membrane bundles are enclosed i n pressure vessel pipes of about 100 to 200mm diameter. Several of th ese bundles may be arranged i n parallel. Clean compressed air is passed i nto these bundles where the oxygen and water molecules are removed. The membranes are heat sensitive and it may be necessary to cool the compressed air before it enters the bundles. The efficiency of th e separation depends on the flow rate through the membranes. A control valve is used to regulate the flow and thereby the oxygen content. The flow is adjusted to give nitrogen of the purity required (typically w ith an oxygen content variable between 0.1% and 5% by volume). Oxygen enriched air is vented as a waste gas, which must be exhausted to a safe area.

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5.13.8 OIL FIRED INERT GAS GENERATORS Oil fired inert gas is generally acceptable for use with petroleum products but it has been found that the quality of the inert gas generated by this type of system is not compatible with many chemical products for quality control reasons. The basic principle of oil fired plants is that the oxygen content of the air is converted to carbon dioxide by combustion of oil while the nitrogen content remains largely unchanged. The oil fuel is burnt in a combustion chamber and the combustion gas is passed through a water tower (or scrubber) to cool it and remove most of the sulphur dioxide, particles and impurities. This requires contact between the gas and large quantities of sea water. The gas may then be dried by being passed either through a cooler or an alumina bed dryer (or both). Chemical tankers are usually fitted with two non-return valves in series as an equivalent to a deck water seal, thereby avoiding the risk of water carry over into the cargo. As a f urther safeguard against backflow, an isolating valve or a spool piece is usually fitted at each branch connection. The inert gas produced by oil fired generators depends on the quality of the fuel oil and th e efficiency of the combustion and scrubbi ng processes. These factors influence, for example, the amount of sulphides i n the inert gas produced (which is why the sulphur content of the fuel is limited i n the plant specification). Likewise, inefficient combustion can cause soot, which clogs the scrubber and, i n particular, the dryer system, thereby producing wet and dirty i nert gas.

5.14 CARGO HOSES 5.14.1 INTRODUCTION A ship's cargo hoses are frequently used during loading and discharge of cargo at a terminal, during cargo transfers between ships and during tank cleaning. Hoses used for the transfer of chemical liquids and vapours during cargo handling operations should be compatible with th e nature and temperature of the ch emical. Any limitations of the cargo properties and temperatures listed by the hose manufacturer should always be observed. The types of hoses normally encountered are either metallic, composite, PTFE (polytetrafl uorethylene) or polypropylene.

5.14.2 CERTIFICATION, MARKING AND TESTING Cargo hoses must be tested and certified. The minimum requirements for the construction and testing of ships' cargo hoses are specified in the IBC Code. All cargo hoses are required to be designed for a bursting pressure not less than five times the maximum pressure that the hose will be subjected to during cargo transfer operations. A manufacturer's test certificate will provide information about the hose's construction and compatibility.

5.14.3 STORAGE AND MAINTENANCE After they have been used, cargo transfer hoses should be washed out, drained, dried and blanked. They should be stored horizontally on solid supports. If hoses are stored in the open, they should be protected from direct sunlight. No attempt should be made on board to repair damaged or leaki ng hoses.

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5.14.4 OPERATIONAL USE When a h ose is being moved about the ship it should always be lifted and carried. It should not be dragged over the ship's fittings such as pipe work or wal kways, or rolled i n a manner that twists the body of the hose, nor hoisted on a crane o r derrick using a si ngle wire strop about its mid-length. Hoses sh ould not be allowed to come into contact w ith hot surfaces such as steam pipes. Before connection, cargo hoses sh ould be examined for any possible defects that may be visible inside the hose or on the outer covering. These may include signs of blistering, abrasion, flattening or evidence of leaks. Hoses with any damage should be assessed and a decision made o n whether they can continue to be used safely. Seriously damaged or leaking h oses should not be used and should be permanently withdrawn from service.

5.14.5 CARGO HOSE CONNECTIONS Gaskets u sed between hoses and at the ship's manifold should be checked for suitability before use. Flanges on both the hose and manifold should be checked for cleanliness and good condition. Bolts and nuts used should be of the correct size and material, with a bolt fitted to every hole in the flange and tigh tened correctly. When in use, a cargo hose should be properly supported along its length to avoid excessive bending of the hose or its weight hanging from the manifold connection. This is especially important when significant tidal o r draft variations can cause the relative heights of the ship and shore manifolds to alter a great deal, requi ring frequent adjustment at the hose support. Fendering, stools or chocks can be used to provide support under the h ose, particularly at the manifold and at the shipside rail. When a hose is supported from above, bridles and saddles should be used to spread the load, and may require more than one supporting poi nt. A si ngle wire strop should n ot be used to support a cargo hose near its mid-len gth . Protection should be provided at points along th e hose where chafing or rubbing could occur.

It is essential that the cargo hose does not provide the primary path for an electrical ch arge between the ship and the jetty, otherwise there is a possibility of an incendive discharge at the manifold when offeri ng up the hose for connection or when breaki ng the connection after the cargo transfer. The necessary electrical discontinuity should be achieved with an insulating flange or a single length of non-conducting h ose in the hose string between the ship and the shore (see Section 6. 7.4).

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x Figure 5. 16 - Handling of cargo Hose

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5.15 ELECTRICAL EQUIPMENT AND INSTALLATIONS IN HAZARDOUS AREAS 5.15.1 INTRODUCTION The specification of electrical equipment and of electrical installations on board chemical tankers is subject to the requi rements of the flag administration, classification societies, IMO and the International Electrotechnical Commission (IEC). Electrical equipment installed in hazardous areas has to be of special construction, and certified safe for the area and the vapours concerned. Portable equipment taken into the area should also be intrinsically safe. One of the main considerations aboard chemical tankers is to ensure that the surface temperature of any electrical equipment does not exceed the auto-ignition temperature of any cargo that the ship may carry. Although there are a number of recognised certification authorities around the world that have slightly different test procedures and ways of groupi ng the surface temperature categories, the IBC Code specifies the temperature groups and equipmen t requirements with which ships must comply.

5.15.2 CERTIFIED SAFE ELECTRICAL EQUIPMENT Intrin sically safe equipment Intrinsically safe equipment relies on low power ci rcuits to limit the maximum energy available to less than that necessary to ignite a flammable mixture under normal and certain fault conditions. Explosion proof or flame proof equipment The terms 'explosion proof equipment' and 'flame proof equipment' are largely synonymous and their use varies from country to country. The safe operation of such equipment relies on a design feature of a particularly narrow ai r gap within the equipment (sometimes called a flame path). The function of the air gap is such that if gas enters the device and is ignited the gas/air is expelled at great speed and the flame is extinguished. The concept is applicable to motors, junction boxes, circuit breakers and a wide range of other electrical equipment. A certificate for the integrity of the equipmen t is issued after laboratory testing. Care is essential in the maintenance and reassembly of this type of equipment to ensure that the designed safety features are not compromised. In particular, the flame path should be kept dry and should never be filled with jointing compound. The correct seals should be fitted at cable penetrations as these contribute to the explosion proof integrity of the equipmen t.

5.15.3 BONDING AND EARTHING A spark cannot jump between two conductors which are either electrically bonded together or if both are earthed. The voltage in each will be equal. Effective bonding is achieved by connecti ng a metal cable between the objects. The cable is sometimes permanently fixed to one conductor and bolted or clamped to the other. At the removable end, contact should be metal to metal and care should be taken to make sure paint, dirt or rust does not interfere with the electrical conductivity. The cable should be strong enough to have good resistance to wear and tear. Bonding and earthing cables should be inspected periodically and thei r resistance checked with a suitable meter. Hoses used in marine transfer operations are designed to have specific electrical properties. Thei r construction i ncludes the use of electrically conductive materials. Only properly constructed hoses that are electrically continuous should be used for cargo operations. When joining hoses together or to a cargo connection, a fully bolted flange joint can be relied upon to be electrically conti nuous so that bonding wires between the flanged connections should not be required (see Section 6. 7.4).

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5.16 BALLAST PUMPROOMS On double hull vessels the ballast pumps are either situated whhin the ballast tanks or sited within a separate pumproom. Designated ballast pumprooms have no permanent connections to the cargo system. Vessels fitted with ballast pumprooms are required to: Have adequate mechanical ventilation; Be provided with bilge high level alarms; Have continuous fire detection; and Have a means to evacuate a casualty from the lower platform level.

5.17 OPENINGS IN DECKHOUSES AND SUPERSTRUCTURES The IBC Code requires that windows and portholes in the superstructure within a certain distance of the cargo area cannot be opened in order to minimise the possibility of vapour entry. These design features must not be modified in any way.

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CHAPTER 6 CARGO OPERATIONS

6

CARGO OPERATIONS

This chapter outlines the range of safety preGJutions to be 1'3ken before and during loading, carriage and unloading operations on chemical carriers.

6.1

Introduction

6.2 6.2.1

Responsibility Personnel and resources

6.3 6.3.1 6.3.2 6.3.3 6.3.4 6.3.5

Planning cargo Operations Introduction Cargo information IMO Certificate of Fitness Stowage planning Specific cargo handling requirements

6.4 6.4.1 6.4.2 6.4.3 6.4.4 6.4.5

Preparation for Cargo Operations Introduction Pre-arrival information exchange Cargo handling plan Ship's personnel Preparing the cargo system prior to arrival

6.5 6.5.1 6.5.2

Port Arrival Procedures Pre-transfer meeting Ship/shore communications during cargo operations Ship/Shore Safety Checklist Action prior to commencing transfer operations

6.5.3 6.5.4 6.6

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6.7 6.7.1 6.7.2 6.7.3 6.7.4 6.7.5 6.7.6 6.7.7 6.7.8 6.7.9 6.7.10 6.7.1 1 6.7.1 2 6.7.13 6.7.1 4 6.7.1 5 6.7.16 6.7.1 7 6.7.1 8 6.7.19 6.7.20 6.7.21 6.7.22

Cargo Transfer Operations Inspection of cargo tanks prior to loading Manifold connections Cargo loading Ship/shore electric currents Cargo pumprooms Correct operation of PN valves Vapour return and vapour balancing Tank atmosphere control Dangers of pressurised loading Topping off procedure Sampling and gauging Sample management Sampling systems Sample storage Ballasting and deballa.sting in port Clearing shore pipelines Completion of transfer Disconnection of cargo hoses Cargo unloading lnerting and tank atmosphere control during unloading Sweeping of cargo residues Completion of discharge

6.8.6

Cargo Care During the Voyage Tank integrity Tank venting Temperature controlled cargoes Inhibited GJrgoes Maintaining an inert atmosphere during the voyage Ballasting cargo tanks

6.9 6.9.1 6.9.2 6.9.3 6.9.4 6.9.5 6.9.6 6.9. 7 6.9.8

Ship to Ship Transfer General Responsibility Communications Navigational warnings Weather conditions and limitations Pr~transfer preparations on each ship Cargo transfer operations Completion of cargo transfer

6.8 6.8.1 6.8.2 6.8.3 6.8.4 6.8.5

6.1

INTRODUCTION Safe and efficient cargo operations require detailed planning and implementation. This can only be achieved provided that th e vessel is supplied with relevant information concerning the type and characteristics of the cargo, that there is sufficient information available on board for planning the safe stowage and handling of the cargo, and that cargo transfer plans are developed in agreement with th e shore terminal. The cargo containment and handling system of chemical tankers is designed and equipped to com ply with th e requirements of the IBC Code and the SOLAS and MARPOL Conventions. Compliance with these regulations will ensure that the ship can safely transport and handle the chemical cargoes that the ship is certified to carry. However, the required level of safety in cargo operations can only be achieved if all parts of the cargo system and related equipment are maintained in good working condition. Similarly, the personnel involved in cargo operations must be fully aware of their duties and be thoroughly trained i n the correct cargo handling procedures and in the use of the equipment. This chapter primarily focuses on the safety and environmental aspects of cargo operations rather than commercial considerations, although these are mentioned where relevant.

6.2

RESPONSIBILITY The Master is responsible for the safety of the ship during all cargo operations. The Master, or a responsible officer (usually th e Chief Officer), should be on board whenever cargo operations are in progress, and must be satisfied that all equipment in use or likely to be used is in good worki ng condition and that sufficient personnel are available. The ship's owner or operator should ensure that the Master has the personnel and resources necessary in order to fulfil this responsibility. In port, the Master should ensure that there is proper liaison between the ship'.s responsible officer and the counterpart ashore. Those responsible should agree on the programme for all cargo operations, and the procedures to be adopted in the event of an emergency. Details of emergency contact names, titles or positions, telephone numbers and methods of communication should be exchanged before cargo operations begin. Any special safety requirements of the shore installation should be brought to the attention of ship's personnel involved. The Ship/Shore Safety Checklist (see Appendix 3) should be completed. Responsibility for safety is shared by everyone concerned, and all must be constantly alert to the particular inherent dangers of the carriage of hazardous chemicals both in port and at sea.

6.2.1

PERSONNEL AND RESOURCES When planning cargo operations the Master should ensure that there are sufficient personnel and resources available for the planned cargo operation and for handling emergency situations. Cargo operations can involve simultaneous loading, discharging and tank cleaning. All of these activities present a high risk to the ship and the crew if not properly managed. The following factors should be among those taken into account when planning manpower requirements: There are sufficient crew and resources available for the planned cargo operation; There are sufficient personnel with the necessary qualifications and experience available for each cargo watch, including a designated supeivisor; All crew members involved in cargo operations are well briefed concerning anticipated operations and cargo characteristics; All crew members are fully aware of their individual roles and responsibilities, as well as those of others;

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The work schedule allows adequate rest for watchkeepers and other seafarers (see Sections 3.10.8 and 3.10.9); There are personnel available to provide back up at times of high workload; There are enough personnel to respond to an emergency situation; and There are other support personnel available when needed.

6.3

PLANNING CARGO OPERATIONS

6.3.1

INTRODUCTION Ensuri ng the safe loading, stowage, carriage and dischargi ng of the cargo is the Master's responsibilit y. Initial information is usually provided to the vessel as voyage instructions and in some cases a proposed stowage plan is included. The Master should consult the applicable certificates and publications on board to ensure that the proposed cargoes can be safely carried by the vessel. Assistance should be available from the vessel's operator in case of queries or doubt. The Master, together with the responsible officer, should carry out a prompt review of the voyage instructions and revert to the vessel's operators with their comments and proposed stowage plan as soon as possible.

6.3.2

CARGO INFORMATION Product information There should be sufficient up to date information available on board to enable the Master to plan the safe stowage and handling of the cargo. Examples of such information sources are: The latest version of th e !BC Code; An up to date chemical dictionary describing the physical properties and h azards of chemical products; Historical shipboard records of cargoes carried; MEPC.2/Circular describi ng the carriage requirements for tripartite cargoes; and Company quality assurance publications and instructions together with customer and i ndustry handling guidelines. IMO shipping name

It is important to correctly identify the IMO shipping name ' 6 and to ensure that the ship is permitted to load the proposed cargo. In all cases the proper IMO shipping name of the cargo must be provided. MSDS A detailed Material Safety Data Sheet (MSDS) should be provided for each cargo to be loaded. The MSDS should provide details of the cargo including its physical properties, guidance on safe handling, health and safety precautions and the action to take in the event of an accidental release into the environment (see Section 1.8.1 ).

6.3.3

IMO CERTIFICATE OF FITNESS A MARPOL Annex II cargo should not be accepted for loading unless it is included on th e vessel's IMO Certificate of Fitness. Any planned cargo not on the Certificate of Fitness should be referred back to the operator.

16 See !BC Code Chapter 16.2.2.

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It is an accepted and common practice for an addendum to the Certificate of Fitness to be issued by the flag administration allowing the carriage of specified additional chemical cargoes in addition to those listed on the Certificate of Fitness.

6.3.4

STOWAGE PLANNING Those responsible for planning the stowage and handling of the cargo should ensure that it can be safely loaded and carried within the certified capabilities of the vessel. When considering the stowage and handling of cargoes the Master or respons.ible officer must ensure: For MARPOL Annex II cargoes, that they are included on the ship's IMO Certificate of Fitness and the proposed stowage complies with IBC Code requirements; For MARPOL Annex I cargoes, that the vessel is equipped to load these cargoes; That there is sufficient tank volume to allow for the expansion of the cargo on the voyage, if heating is required, or if the vessel will transit between areas of different ambient temperatures; If a tank will only be part loaded, that the loading complies with any cargo tank filling restrictions; If the cargo has a high specific gravity, that the loading complies with any cargo tank filling restrictions; That the setting of cargo lines, valves and vent lines will ensure that incompatible cargoes remain segregated; That each cargo w ill be stowed so as to be compatible with cargoes in adjacent tanks (refer to the USCG Compatibility Chart, see Section 1.6.6); That heated cargoes will be stowed so as not to be adjacent to heat sensitive cargoes or where a heat source could lead to a dangerous reaction; That any tank coating heating restrictions are complied w ith including coatings applied to adjacent tanks and spaces; That cargo tank coatings are compatible; That any heating restrictions due to structural considerations are complied with; That any specific cargo tank venting requirements, such as vapour return, are complied with; That any specific tank cleanliness or preparation requirements are complied with; That the planned stowage will ensure that the ship can carry out cargo operations in port within its stress and stability limits; That the planned stowage will ensure that the ship can proceed to sea in a stable, seaworthy condition and within approved hull stress limits; and That the planned stowage complies with IBC Code damage stability requirements. The Master should always approve the cargo stowage plan.

Cargoes should not be accepted for shipment if there is any doubt concerning the specification of the cargo or of the ship's capability to comply with the loading criteria.

6.3.5

SPECIFIC CARGO HANDLING REQUIREMENTS Heated cargoes Highly viscous products might need to be heated in order to reduce their viscosity and enable the cargo tanks to be stripped effectively at the discharge port. Detailed heating instructions should be obtained from the shipper.

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Products that have a melting point which is close to or higher than the expected ambient conditions require heating to prevent freezing of the cargo. Heated cargoes requiring prewash The IBC Code for certain products requires that the product viscosity at 20'C must be specified on the shipping document. If the viscosity at 20'C is above SO mPa.s then the temperature at which the viscosity equals SO mPa.s should be stated.

If the product viscosity at the actual discharge temperature exceeds SO mPa.s a prewash with delivery of slops to shore is required. When appropriate, the IBC Code also requires that the product's melting (solidifying) point is indicated on the shipping document. Solidifying substances are defined relating to their temperature at the time of discharge: l ess than S' C above the melting point - for substances with melting point of or less than and 1

s·c

l ess than 1O'C above the melting point - for substances with melting point above 1S'C. Unless solidifying cargo is discharged at temperatures higher than those above, a prewash with delivery of slops to shore is required . When planning the carriage of particular cargoes, it is suggested that cargo viscosity information is considered to determine whether or not a prewash and other measures are required . Cargoes requiring tank atmosphere control

Some highly reactive cargoes require the ullage space to be kept inerted with nitrogen in order to maintain the cargoes in a stable condition . Tank atmosphere control, using nitrogen, may also be required for quality control reasons, usually specified by the shipper, in order to prevent chemical deterioration of the cargo or protect hydroscopic cargoes from absorbing moisture. When planning cargo operations the availability of nitrogen will need to be arranged so that the ship can comply with the inerting requirements. The nitrogen will either be supplied from ashore, on board storage (cylinders or bulk tank), or the ship w ill be equipped with its own nitrogen generator. Inhibited cargoes

Some cargoes require an inhibitor to ensure that they remain chemically stable during transit. Such cargoes should not be stowed adjacent to heated cargoes. Prior to agreeing to load inhibited cargoes the Master should ensure that sufficient inhibitor has been or will be added to the cargo for the expected voyage length. An inhibitor certificate must be provided to the ship verifying that the inhibitor has been added. Adding of substances such as powdered inhibitors and other similar material may generate a static charge if introduced to the tank by free falling or pouring the substance from an opening on the cargo deck. Consequently at the pre-loading meeting it should be emphasised that any inhibitors should be added to the cargo prior to loading (see Section 1.4). Many inhibitors are oxygen dependent. Should the cargo be required to be kept inerted, information should be sought from the shipper concerning the minimum amount of oxygen required to ensure that the inhibitor remains effective (see Section 1.8.3). Toxic cargoes and antidotes For some toxic cargoes antidotes are available in case personnel are accidently exposed to the cargo liquid or vapour. When antidotes are provided they should be available before loading and should be accompanied with detailed instructions for their use (see Section 10. 7). The provision of antidotes should not lead to a relaxation of safe cargo handling practices or of the requirement to use appropriate PPE.

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Cool ed cargoes

Some cargoes need to be cooled in o rder to reduce evaporation from high vapour pressure cargoes or to ensure chemical stability. Cargoes that require cooling should only be accepted on vessels designed and equipped for cooling in compliance with Chapter 7 of the !BC Code. When cargo coolers are used the level of cargo must be sufficient to cover the impellor at any stage of the voyage. Cargoes carried using over pressure High vapour pressure cargoes can be carried using a slight over pressure in order to reduce evaporation. When agreeing to load such cargoes the ambient temperature conditions during the voyage, and at the ports of loading and unloading, must be taken into account so as to avoid excessive evaporation of the cargo. Boundary cooling, especially of the deck, will help to reduce the rate of evaporation in hot ambient conditions, but local restrictions may restrict this type of operation. Where cargo tanks and their venting systems are designed to withstand the additional vapour pressure of such cargoes a notation must be included on the vessel's IMO Certificate of Fitness.

See also the IBC Code Chapter t 5.14. Blended cargoes There may be occasions where cargoes are loaded as separate components and blended on board in order to make up the final product to be shipped. Physical blending also refers to the process whereby the ship's cargo pumps and pipelines are used to circulate internally two or more different cargoes with the intention of producing a cargo with a new product designation. Before agreeing to a proposed blending operation, it should be confirmed that each of the com ponent grades, together with the final blended product, are included on the vessel's IMO Certificate of Fitness. Blending operations need to be carefully planned and clear instructions provided. Should the Master have reservations concerning the safety of the planned operation then the vessel's operator should be contacted for guidance. SOLAS prohibits the physical blending of bulk liquid cargoes during sea voyages (see Section 4.3.2). Cargo blending operations Prior to agreeing to a cargo blending operation on board, the Master should ensure that the following checks are carried out: Confirmation that the ship is allowed to carry the individual products to be used as well as the final blended cargo; Clarification as to whether the cargo is to be shipped as a MARPOL Annex I or Annex II product; If carried as an Annex I product that the oil discharge monitoring equipment (ODME) is typeapproved for the final blended cargo; If the ODME is not type-approved for the final blended cargo, that arrangements are made to transfer residues and tank washing slops to a shore based facility at the discharge port; and That there are clear guidelines on how the loading, blending, unloading and the disposal of tank residues after cleaning are to be recorded in the Oil Record Book or the Cargo Record Book as applicable.

See also Sections 4.3.1 and 4.3 .2 of this Guide. Should cargo blending be required to be carried out by the vessel then this should only be accepted provided that: The vessel's cargo pumping and piping system is suitable; Sufficient cargo capacity is available; Stability and stress on the hull will be maintained within acceptable limits; and The blending operation will be carried out within port limits.

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Internal cargo transfer Should it be necessary to transfer cargo from one tank to another, precautions and checks should include the following: That the vessel's cargo pumping and piping system and tanks are suitable; That the tank to receive the cargo has sufficient capacity; That the tank atmosphere control is maintained as required; That the stability and stress on the hull is maintained within acceptable limits; That the vessel's trim and draft are maintained within required limits; and

If cargo transfer results in the blending of cargo that this is carried out within port limits (see Section 4.3.2).

6.4

PREPARATION FOR CARGO OPERATIONS

6.4.1

INTRODUCTION Detailed planning and preparation of the vessel and its systems for cargo operations, prior to arrival in port, is essential to ensure a safe and efficient port call. Preparation should require that: Vessel personnel are prepared and briefed; Cargo equipment and support systems are tested and ready; Contingency plans are developed for potential emergency situations; and An information exchange between the ship and the terminal has been established.

6.4.2 PRE-ARRIVAL INFORMATION EXCHANGE Operations concerning cargo handling, prewash, tank cleaning, ballasting and bunkering require an exchange of information between the ship and shore prior to the ship arriving in port. The following should be considered for inclusion in such an information exchange so that both the ship and the shore can plan their operations prior to arrival: The maximum draft allowed alongside and in the approaches to the berth; Under keel clearance limitations and whether there are any other dimensional limitations such as air draft, beam or freeboard; Tidal range alongside and any special mooring arrangements; Cargo specifications, to include inter alia the approved IMO shipping names, the nominated quantities to be transferred, expected temperature of cargoes during transfer, flash point (where applicable), specific gravity, the MARPOL pollution category if applicable, and any viscosity and solidifying information; Availability of MSDS including emergency and health data for each cargo to be handled; Where the ship has multiple or in transit cargoes, the cargo name, volume and tank distribution of each cargo; Any special cargo handling requirements; Proposed stowage of cargo and preferred order of loading or discharge; Details of cargo tank preparation for loading, including previous cargo carried, method of tank cleaning (if any), state of the cargo tanks and lines; Tank inspection and testing procedure;

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Whether foot samples or other samples are to be taken, and any su spension of cargo operation while samples are bei ng analysed; Number and sizes of hoses or loading arms to be used for each cargo, and any limitations on the movement of hoses or loading arms; Whether the vessel will be requi red to reposition alongside when changing grades or to utilise other shore connections; Maximum pumping rates and maximum back pressure limitation at the manifold connection, and any restrictions due to inherent properties of the cargo; Restrictions relating to any electrostatic properties of a product, and precautions to prevent the generation of hazardous static electricity charges; The use of shore automatic emergency shut down valves, and their closing period; Any restrictions on tank venting requirements and, should vapour return be required, a full description of the terminal's system including hose sizes and pressure and capacity limits; Tank environmental control requirements, e.g. drying and inert gas, and quality of inert gas (if applicable); Terminal or port regulations on prewashing of cargo tanks alongside the berth, and details of reception facilities available to receive slops (if applicable); Mandatory prewash requi rements, cargo names and quantity of washings for discharge to reception facilities, and quantity, quality and disposition of slops (if applicable); Whether alongside tank cleaning is required in addition to prewash; Whether other operations such as bunkeri ng or storing are permitted to be carried out concurrent with cargo operations. If not, agree on when such operations can be planned to take place; Restrictions on the pumpi ng of ballast water (see Section 4.6); and Any other pertinent information for the terminal or the ship, including access arrangements and limitations.

6.4.3

CARGO HANDLING PLAN On the basis of the information exchanged between the ship and th e shore, a documented cargo handling plan must be prepared by the responsible officer and checked and en dorsed by th e Master. For port calls i nvolving more than one berth a separate cargo handling plan should be prepared for each berth.

Confirmation is needed on whether cargo completion will be subject to a shore or ship stop. This does not relieve the ship from its responsibility to stop cargo within safe and agreed parameters.

The plan should address, but not be limited to, the following where applicable: The quantity and stowage of each cargo grade; Sampling requirements; The sequence of cargo operations i ncluding ballasti ng requirements and ballast plan; Identification of critical stages in the operation; The density, temperature and other relevant properties of all cargoes; A pipeline system plan showing the setting of valves, lines and pumps to be used; Transfer rates and the maximum allowable pressures;

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Start up procedure; Completion procedure, shore stop/ship stop and absolute stop ullage for ship; Emergency stop procedures and contacts; Action to be taken in the event of a spill; Cargo pollution category and USCG compatibility number; Flammability and toxicity data (including antidotes as applicable); Fire protection measures i ncluding the relevant fire-fighting agent(s) and the arrangement of portable fire-fighting equipment; Venting requirements and vapour return; Ship stability and stress information; Draft and trim details; Personal Protective Equipment (PPE) requirements; Hazards of particular cargoes; Mixing of vapours withi n vent lines; Inhibitor requirements; Inert gas or nitrogen requirements; Cargo viscosity data; Cargo melting point (solidifying or freezing cargoes); Cargoes requiring prewash; Cooling requirements; Precautions against static generation; Control of cargo heating systems; Line clearing requirements; Under keel clearance limitations; Bunkering plans; Details of other planned activities, e.g. bunkering, storing, repairs or major crew changes; Potential hazards associated w ith the inadvertent mixing of cargoes in slop tanks and drip trays and associated line systems; and Any special mooring requirements.

6.4.4 SHIP'S PERSONNEL Information sharing Prior to arrival it is important that all on board are informed of the intended port programme. All personnel directly involved in cargo operations should be formally briefed regarding the cargo handling plan. A copy should be provided to all involved and watchkeeping officers should be required to sign that they have read and fully understood the plan. IMO regulations require that cargo i nformation is available to all concerned on board. It is therefore recommended that MSDS sheets for all the cargoes presently on board, and to be loaded at the next port, are prominently displayed so as to be available to all crew members.

It should be clearly understood that, during cargo operations, access to the cargo deck is restricted to essential personnel only.

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Personal Protective Equipment (PPE) All ship's personnel should be provided with appropriate PPE and additional PPE should also be available to third parties as necessary, especially if they will be working on the cargo deck. PPE should be appropriate for the cargoes to be handled and for the climatic conditions expected. For more details on the use of PPE refer to Section 3.11 of this Guide.

6.4.5

PREPARING THE CARGO SYSTEM PRIOR TO ARRIVAL Before arrival in port an inspection and test of the cargo system and its control and monitoring systems should be carried out. This will allow for any necessary repairs or adjustments to be completed prior to arrival. Should equipment be found not to f unction as designed, any agreement to proceed which utilises alternative measures to control the safety of the operation should only be permitted after a f ull risk assessment has been carried out. The severity of the sit uation w ill depend on the equipment or systems affected but, in all cases, the decision to proceed should be considered as a non-routine operation. Effective control measures implemented as a result of the risk assessment should be agreed to by all parties involved, including but not limited to the vessel's operator, charterers, the terminal and the port authority (see Section 3. 7). Cargo lines and valves As much of the lining up of cargo lines and valves as possible should be done prior to arrival. If the cargo handling plan requires that a single grade of cargo is to be loaded or uni oaded from several tanks served by a common pipeline system, containment within each tank depends upon the tightness of the valves. Due to the pressure differential on either side during sequential loading or unloading, the tightness of a single valve should not be relied upon. Loading should be planned so that when a tank is completed a minimum of two valve segregation can be maintained between the completed tank and the loading or unloading of other tanks within the set of tanks. The cargo handling plan should stipulate the sequence of loading and unloading multiple tanks and the need for regular checks to be made on completed tanks to ensure that the level of cargo does not change. When carrying toxic cargoes, it is an IBC Code requirement that cargo piping, pumps and tank venting systems are kept fully separate from other tank systems. Most modern chemical tankers are provided with a separate pump and line for each tank and therefore maintaining full separation is achieved by design. The plan should stipulate that all cargo lines used to handle toxic cargoes are tested with air or nitrogen immediately prior to cargo operations to test for leaks. For vessels fitted with com mon pipeline systems full separation can be achieved when carrying toxic cargoes by: Inserting two blank flanges (spectacle plates) w ith a bleed drain in between. The engineering principle of using two stops, with a provision for detecting if one of the stops does not hold tight (block and bleed principle) should ensure that a leak can be detected; Removal of a section of line, that connects one tank or system to the other, and blanking the exposed ends; and Utilising purpose built double blank valves. These valves have a cover which can be swung aside and a double blank inserted and tightened so that each end of the valve is blanked. Any leakage will be immediately apparent. Once a cargo operation plan has been made and the lines and valves have been set, the entire system should be checked by a responsible officer to ensure that: The valves and lines are correctly lined up and the valves correctly set; Drain valves, plugs and sampling connections are all closed and capped where necessary;

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Unused flanges are securely blanked;

PN valves are correctly set; If vapour return is to be used, that the vapour lines are correctly set; Hatches, lids and openings to cargo tanks that are not required to be open for a specific reason are securely closed; and Unless it is to be used, the stern cargo pipeline is isolated from the tanker's main pipeline system at a point foiward of the accommodation . Changes to the plan should only be made with the authority of the Master by a responsible officer. Deck lighting and electrical fittings The condition of cabling, electrical fittings and cargo area deck lighting should be checked and confirmed as being in safe working order. All deck lighting fittings should have their protective glass covers fully bolted and fitted with the correct sized lighting element. Any defects to equipment should be reported in order to allow repairs or adjustments to be made prior to arrival. Deepwell pumps Prior to use, hydraulic deepwell pumps should have their cofferdams purged to ensure that the cargo and hydraulic seals are leak free.

If possible, the pumps should be tested to ensure that the impeller is free and that the pump is ready for use. Cargo pumprooms Bulkhead glands fitted where the drive shafts pass between the pumproom and the adjacent machinery space should be checked and adjusted or lubricated, as necessary, to ensure an efficient gas-tight seal. Pumproom fans and the operation of fire flaps and other safety features fitted to the pumproom should be tested. Cargo pumproom bilges should be maintained clean and dry. In the event of a leak, the product should be transferred to a slop receptacle taking into account the risk of incompatibility with other products. Enclosed space entry precautions should always be followed when entering pumprooms (see also Chapter 9 of this Guide). Setting P/V valves Where a PN valve's operating parameters can be adjusted, the correct pressure setting for the product to be handled should be confirmed. Vent lines and PN valves must be checked for correct operation prior to arrival. Malfunction or blockage due to cargo vapour freezing, polymer build up, atmospheric dust, or icing in adverse weather conditions can easily result in structural damage to a tank. If fitted, heat tracing lines should be tested and used if required for the cargo. Flame screens are particularly susceptible to blockage and should be checked to ensure that they are clear. Heating and cooling systems

If the cargo to be loaded requires heating or cooling the integrity of the system should be inspected and tested for tightness.

If the heating or cooling medium is incompatible with the cargo to be loaded the system should be blown through and the coils blanked prior to loading. Inert gas systems The inert gas system should be checked and regularly tested to ensure that it performs according to specifications and that all the safety and monitoring systems are working correctly. The fixed oxygen analyser check should be carried out prior to arrival.

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Alarms and instrumentation The following alarms and monitoring equipment should be calibrated for accuracy and reliability: Tank instrumentation including cargo level gauges, high level alarms, pressure and temperature sensors; Remote read outs and control systems; and Cargo and ballast pumproom alarms and gas monitoring devices. Recording of checks and tests of equipment It is recommended that vessel specific checklists are developed to record the pre-arrival tests of the cargo system and associated monitoring equipment.

6.5

PORT ARRIVAL PROCEDURES

6.5.1

PRE-TRANSFER MEETING The responsible officer, together with the responsible tenminal representative, should meet to plan and agree the sequence of operations. If necessary the ship's cargo handling plan should be updated, based on the information exchanged, and the revised plan provided to all concerned. Amongst other possible issues the following should be addressed at the pre-transfer meeting: Compliance with terminal regulations; The sequence of cargoes to be loaded and unloaded; Although the line up of pumps, lines and valves will have been checked and verified prior to arrival, orders may have changed once the vessel arrives alongside which may require changes to be made. In such circumstances, the responsible officer should ensure the changes agreed are incorporated into the cargo handling plan, distributed and understood by all involved; Responsibility for the connection and disconnection of shore hoses and loading anms; The identification of manifold connections for each grade; Agreement on the maximum allowable back pressure or loading rate for each grade; Agreement on vapour line connection; Maximum operating pressure and loading rates for cargoes requiring vapours to be returned to the terminal; If a cargo liable to self-reaction is to be loaded, assurance from the terminal that, prior to loading, sufficient inhibitor has been added to the cargo and that sufficient is available for the expected voyage length (including an adequate safety margin); Ship/shore communication protocols. Refer to Section 6.5.2; Whether cargo operations will be subject to ship or shore stop; Agreement for clearing ship and shore lines and whether the contents of shore lines will be displaced to the ship and if so the quantity of the displacement; Precautions to avoid the over pressurisation of cargo tanks; Agreement for any supply of nitrogen from the shore for the inerting or padding of tanks; Agreement on when other activities such as bunkering or storing can take place; and Any restrictions on access to the vessel or the terminal.

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6.5.2

SHIP/ SHORE COMMUNICATIONS DURING CARGO OPERATIONS Effective communications between the ship and the terminal are essential to ensure safe cargo operations. Prior to any operation commencing it should be agreed how the communication link between the ship and the terminal will be managed. Once agreed the system should be tested. Furth er tests should be conducted at agreed i ntervals and, as a minimum, at the changeover of a watch. Should the main means of communication fail an agreed secondary means of communication shou Id be available. Critical phases of cargo operations require the complete attention of both ship and shore personnel. In some ci rcumstances the terminal may not be able to respond immediately to requests from the vessel as not all pumps and controls may be centrally located. Duri ng the pre-transfer meeting the vessel should establish if an allowance should be made for the time required to respond to instructions. Nonetheless, it is always good practice to give ample notice to the terminal prior to giving instructions to stop or change a cargo operation. Any language difficulties should be addressed at the pre-transfer meeting before operations commence so that the communication procedure agreed is simple, effective and understood by all. The use of one radio channel by more than one ship/shore combi nation should be avoided.

Prior to commencing cargo operations an emergency shutdown procedure should be agreed with the terminal.

6.5.3

SHIP/ SHORE SAFETY CHECKLIST The Ship/Shore Safety Checklist addresses the ship/shore interface concerning the safety of the ship while alongside the terminal. Each item should be verified. This will entail a physical check by the two responsible persons concerned, one representing the ship and the other representiing the terminal. The Ship/Shore Safety Checklist is a comprehensive and i mportant document. Providing it is completed accurately, it is confirmation that all the requi red safety precautions, while alongside the terminal, have been complied with and followed.

It is emphasised that some of the items on the Checklist should be repeated regularly during the vessel's enti re stay alongside the terminal, for example mooring and communication checks. An example of a typical Ship/Shore Safety Checklist and guidelines for completion is included in Appendices 3 and 4.

6.5.4 ACTION PRIOR TO COMMENCING TRANSFER OPERATIONS Before commenci ng any cargo operation the applicable precautions, as described in Chapter 2 of this Guide, should be observed . The use of safety checklists adapted to each specific ship is strongly recommended. However, the following checks and control activities should be carried out and monitored by the watchkeepi ng officer prior to commencing any transfer operation: Ensuri ng that the vessel is securely moored; Access to the ship is safe and complies with terminal and ISPS Code requirements; All openings i n the accommodation are closed and access restricted, as far as practicable, to only one entrance, which should be clearly marked; Where possible, and when appropriate due to toxicity of cargo, accommodation air conditioning to be on recirculation mode; The agreed communication with the terminal has been tested and confirmed;

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Information should be sought on any forecast of adverse weather conditions which may require cargo operations to be suspended; All deck scuppers and any open drai ns on the cargo deck must be plugged. Means of transferri ng any accumulated liquid should be rigged and be ready for use; Where loading or discharging is to be via a cargo pumproom, the pumproom ventilation system is in operation and all drains and non-essential valves in the pumproom kept closed; When not in use, sea suction and overboard discharge valves connected to cargo and ballast systems must be securely closed and lashed, and may be sealed by shore authorities. In line blanks should be i nserted where these are provided. When lashing is not practical, valves should be suitably marked to indicate clearly that they are to remai n closed; Portable fire-fighting equipment should be in place and ready for immediate use; Correct personal protective clothing and breathing apparatus, appropriate to the cargo, should be available, and should be worn as necessary; Manifold connections are clearly marked w ith the grades to be handled; All manifold connections should be blanked and fully bolted until needed; The shore lines are securely connected to the correct manifold connection. Hoses or shore loading lines that are not in good condition or not properly connected should be rejected; Manifold vapour return connections are secure and the maximum loading rates and allowed back pressure have been agreed with the terminal; The line up of lines and valves conforms with the cargo handling plan. A secondary verification check should be carried out by a responsible person; All drains and other openings i n the cargo system should be closed or blanked; Air or nitrogen leak testing including of the ship/shore connections, portable connections, common line connections, and connections to reducers and jumpers should be carried out prior to transfer operations; and Once tanks have been accepted for loading all openings should be closed.

6.6

MONITORING CARGO OPERATIONS Cargo operations should be continually monitored and be under the control of a watchkeeping officer. While many of the watchkeeping officer's functions require them to be based in the cargo control room, their responsibilities extend to the entire cargo operation. It is good practice that at regular intervals the officer is relieved by another responsible person so that an inspection can be made of the cargo deck to ensure that the cargo operation is proceeding safely and according to the cargo handling plan. Prior to taking over a watch the relieving officer should make a tour of the cargo deck and mooring areas to ensure that all operations are proceeding safely. Specifically designed checklists should be developed to ensure that all relevant information is passed on to the relieving officer. A crew member should always be on watch on the cargo deck and be in constant radio contact with the watchkeeping officer. The duties of the deck watch will include making regular rounds of the deck to check that the moorings are correctly adjusted and that there is equal tension on all lines. During the rounds all areas of the cargo deck should be inspected to ensure there are no leaks or other developments that could affect the safety of the cargo operation and that access to the vessel is clear and safe.

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Loss of containment such as cargo overflow through the PIV system may have serious consequences for personnel. the environment and to tank structures and also create an unsafe atmosphere. To mitigate such risk. it is very important to carefully plan and monitor loading/discharge to ensure that it does not exceed the ship's cargo handling capability.

The watchkeeping officer's principal duties include: Implementing and managing the cargo handling plan and maintaining a log; Being the principal point of contact with the shore terminal; Controlling and verifying the performance of the following: The correct functioning of tank level gauges and tank level alarms; The operation of cargo pumps and valves; Controlling the distribution of ballast; Operation of the inert gas system; Ensuring that safety and fire-fighting equipment is ready for immediate use; Ensuring that all watchkeepers are using appropriate PPE; and Ensuring that there are no unplanned activities being carried out.

Watchkeeping officers should understand that they have full authority to take immediate effective action to prevent a situation developing that threatens the safety of the ship.

6.7

CARGO TRANSFER OPERATIONS

6.Zl

INSPECTION OF CARGO TANKS PRIOR TO LOADING Normally tanks will be inspected for cleanliness by a tank inspector acting on behalf of the shipper of the cargo. Inspection procedures vary from a basic check of the cleanliness of the tank to the requirement to carry out a wall wash test of the tank surfaces to assess the suitability of the tank for the nominated cargo. A tank inspector should never be allowed to enter a tank without the permission of the ship's responsible officer. The ship's enclosed space entry procedures should always be complied with and the tank inspector accompanied by the watchkeeping officer and kept under observation at all times.

No tank entry should be made when any inerting operations are taking place anywhere on board the ship.

Wall wash testing of a tank utilises a chemical, usually methanol, which is sprayed on to the tank sides and recovered in a sample bottle which is then sent ashore for testing. This procedure must be carefully controlled as the wall wash process exposes the personnel to harmful vapours. The total amount of methanol used should be the minimum required to complete the test. It should be noted that elevated temperat ures will increase the volume of vapours produced. Great care should also be taken when lowering and recovering samples from the tank, and the responsible officer should ensure that this operation is carried out safely.

See also Chapters 8 and 9 of this Guide.

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Any tank to be entered must be completely disconnected from any active cargo operations.

6.Z2

MANIFOLD CONNECTIONS Loading can be either via a shore hose or a loading arm. Whatever system is used the shore connection and the manifold flanges should be clean and in good condition. The gaskets used should be resistant to the product to be loaded. A bolt should be fitted in every hole, and tightened correctly and evenly. Nuts and bolts should be of the correct size and material, and damaged bolts should not be used. Improvised arrangements using G-clamps or similar devices should not be permitted under any ci rcumstances. Care should be taken to protect manifolds from damage. In most cases, terminal hoses will be used for the connection between the ship and the shore. During connection, and when connected, flexible hoses should be suspended by suitable equipment to ensure that they are not subjected to excessive bending or be liable to crushing between the ship and the dock. As the ship rises and falls, as a result of the tide or cargo operations, the hose strings should be adjusted so as to avoid undue strain on the hoses and the ship's manifold, and to ensure that the radius of curvature of the hose remains within the limits recommended by the manufacturer. If loading arms (sometimes referred to as hard arms or 'Chiksans') are used, the installation arrangements will have taken account of the tidal range, the freeboard of the largest and smallest ships using the berth, and the minimum and maximum distances that manifolds are set back from the deck edge. Loading arms are restricted i n their movement and can only operate within set tolerances. Excessive movement of the vessel up and down the dock may cause these tolerances to be exceeded and it is therefore important that moorings are properly tended. Movement limits should be thoroughly understood by terminal operators, and alarms for excessive range and drift regularly tested. If range or drift alarms are activated while in service all cargo transfer operations should be stopped and remedial measures taken. Some termi nal loading arms utilise a locking cam system to secure the flange. These arrangements are usually only fitted to large capacity loading arms which can impose excessive strain on chemical tanker manifold connections. Loading arms should be designed and supported in such a way that they do not put excessive force on the manifold. The IBC Code requi res that flanges at the manifold are provided with shields to guard against spray from acid cargoes. It is recommended that consideration is also given to the use of such shields to protect against spray from other cargoes that are toxic or corrosive.

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Figure 6.1 - Shore Cargo Connection Reducers and spool pieces should be made of suitable material compatible with the cargo, and comply with relevant industry standards. Where long reducers or spool pieces are used the resulting lengths should be properly supported to prevent undue stress. Every manifold opening should have a removable blank flange, made of an approved material. Before removing a blank flange, a check should be made to ensure that the section of pipeline between the manifold valve and the blank is not pressurised or does not contain cargo. Any product in the space should be safely collected in a suitable container for disposal. All work involving the connection and disconnection of hoses and loading arms at the manifold risks exposing the crew to cargo and vapour under pressure. Crew members should wear appropriate PPE in addition to their normal deck PPE. When toxic cargoes are involved breathing apparatus should be worn. See also Section 3.11 of this Guide.

If a leak is detected the affected cargo operation should be stopped and the situation resolved. In the event of a major leak the situation should be treated as an emergency and all cargo operations should be stopped.

Whenever cargo operations are stopped the manifold valves should be closed.

6.Z3

CARGO LOADING General Cargo loading is an operation not fully under the control of the ship because the transfer of cargo to the ship is managed by the shore terminal. l oading rate Commencement of loading should be at a slow rate until it has been verified that the cargo is being loaded into the correct tanks, that there are no leaks in the system and that all monitoring systems are functioning correctly.

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On the satisfactory completion of initial checks the loading rate can be increased to the maximum rate agreed at the pre-transfer meeting. Checks during loading At regular intervals throughout the operation, checks should be made to ensure that the cargo is not leaking and that tanks are being loaded according to the agreed transfer plan. Remote read outs from tanks should be checked for accuracy by utilising the closed gauging equipment. High level alarms and tank overflow control alarms are safety critical items, and loading should be stopped if it is suspected that either is not working correctly. Prevention of static during loading A ship's tanks should only be loaded using the vessel's fixed pipeline system where the liquid enters the tank at the bottom of the tank so that, in the early stages of loading, turbulence is kept to a minimum. When the rising liquid level in the tank covers the pipeline inlet, turbulence in the tank is considerably reduced and the risk of generating a static charge diminishes. Turbulence increases the generation of static electricity. Therefore splash filling, where the cargo is allowed to freefall into the cargo tank from an open ended hose, should be avoided. Where splash filling is a custom of the trade, for example with certain vegetable oils and w ine, then a risk assessment should be carried out to address any potential risks, including damage to the cargo.

Splash filling should never be used when loading static accumulating cargoes.

Safe pumping rate The faster the liquid flows through the vessel's pipeline during loading or discharging, the higher the potential for creating electrostatic charging. To avoid excessive t urbulence during the loading of a cargo that is known to be a static accumulator, the loading rate should be kept low until the inlet to the cargo tank is well covered.

6.Z4

SHIP/ SHORE ELECTRIC CURRENTS Voltage differential between ship and shore When a ship is connected to a shore installation by an electrically conductive hose or a metal loading arm the ship, hose, dock and water combine to form the elements of a battery with the potential to generate a large current. When the hose is disconnected the current is suddenly interrupted and an electrical arc can be formed between the flanges of the shore connection and the ship's manifold with the risk of igniting any flammable atmospheres present. In order to break the circuit an insulating flange is installed, usually on the shore side, so as to prevent the generation of a ship/shore voltage differential. All metal on the seaward side of the insulating section should be electrically continuous to the ship, and all metal on the landward side should be electrically continuous to the jetty earthing system . An insulating flange should also be fitted to the vapour return system. Ship/shore bonding The use of a ship/shore bonding cable is not only considered to be ineffective but could also be dangerous. It should be noted that in MSC.1/Circ. 1216, IMO has urged port authorities to adopt the recommendation concerning the use of an insulating flange or a non-conducting hose to ensure electrical discontinuity between the ship and shore. A ship/shore bonding cable, if used, does not replace the requirement for having an insulating flange fitted between the shore hose and the terminal piping system. Best industry practice advises that bonding cables between the ship and shore are unnecessary and, in some cases, they could increase the risk of generating an incendive spark.

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Should a shore terminal require the connection of a bonding cable it should be connected to the ship clear of the manifold area. The connection should be metal to metal and the isolation switch on the shore should be i n the off position until both ends of the cable have been securely fastened. The cable should be attached before the cargo hoses are connected, and removed only after the hoses have been disconnected. When in line strainers are used they should be sufficiently bonded.

6.ZS

CARGO PUMPROOMS During all cargo operations, including loading, the pumproom should be inspected at regular intervals to check for signs of leakage from glands, drain plugs and drai n valves, especially those fitted to cargo pumps. If the pumps are in use, pump glands, bearings and bulkhead glands should be checked for overheating. In the event of leakage or overheating the pump should be stopped. No attempt should be made to adjust pump glands on rotati ng shafts while the pump is in use. At all times when entering a pumproom, enclosed space entry procedures are to be complied with. See also Chapter 9 of this Guide.

6.Z6

CORRECT OPERATION OF PNVALVES The cargo tank venting system should have previously been set for the type of operation to be performed. Cargo vapour displaced from tanks during loading or ballasting should only be exhausted to atmospheres through the tanks' venting system, unless vapours are being returned to shore. The loading rate should not exceed the maximum flow rate of the tanks' venting system.

PN valves contai n a flame screen. Particular attention should be given to checking that flame screens do not become blocked by ice, condensed cargo vapour or other contaminants. Some older vessels' tanks are protected by a common venting system where vent lines are grouped together and served by a single PN valve. Such arrangements can lead to cross contamination of cargo vapours from one tank to another. In the event of overfilling a tank, liquid contamination can also occur. Such arrangements are seldom found on modern vessels where it is now common practice to provide a separate vent line and PN valve for each tank. In order to ensure the correct functioni ng of PN valves the following should always be complied with:

PN valves should be serviced and calibrated according to classification society requirements; Prior to loading and discharging, PN valves should be checked to ensure they function as designed; During cargo operations the correct functioning of PN valves should be monitored; and Pressure sensors fitted as the secondary system as a back up to the primary vent system should be checked to ensure that they function as designed and, where provided, that the alarms are correctly set.

Setting P/V alarms High pressure alarms and low pressure alarms must be set to: Activate additional safety or other alarm systems; Support maintenance of correct positive inert gas pressure i n tanks; Prevent air intake to tanks; and Comply with regulations.

Monitoring Tank pressure should be monitored by the fixed monitoring system, and recorded at regular intervals. Alarm settings should be adjusted to provide warning should the PN valve fail to operate correctly.

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6.Z7

VAPOUR RETURN AND VAPOUR BALANCING The vapour return system sh ould only be used with compatible shore systems w here both the vessel and the shore have an agreed procedure for its use and the action to take in an emergency. The IBC Code requires that vessels are equipped to return vapours of certai n toxic chemicals to shore. When a tank is connected to a vapour return line, it is important to maintain a safe pressure balance between the ship and shore. The vapours should be evacuated by the terminal's system at a rate to keep the pressure in the tank below the set opening pressure of the PN valve. Prior to commenci ng a vapour return operation it is important to agree in advance with the shore terminal what the loading rate of the product will be and how the pressure i n the vapour return line will be maintained. It should be noted that when pump rates are changed the pressure within the system lags behind the pump's operation. Consequently the pressure should be mai ntained w ithin 80% of the PN valve limit . Achieving this target w ill be aided by starting cargo loading slowly and gradually increasing the rate to agreed limits. Liquid should not be permitted to enter the vapour return line. If liquid gets into the vapour line it will cause the cross section available for the flow of vapour to be reduced, as a result of which the pressure inside the tank can rise rapidly. Loading should be suspended until the pressure is released, and the presence of liquid in the vapour return line dealt with by the crew. Vapour balancing Vapour balancing describes the process where displaced air, inert gas or nitrogen from the shore tank is returned to the vessel's tanks during unloading. In effect it is vapour return in reverse and the same precautions should be obseived to prevent over or under pressurisation of the tank.

6.ZS

TANK ATMOSPHERE CONTROL Inert gas lnerting the atmosphere in a cargo tank reduces the oxygen content below that which can support combustion. For further information on the use of inert gas refer to Chapter 7 and Section 4.5 of this Guide. Use of nitrogen or dried air as a drying medium When loading a water reactive cargo the cargo tank atmosphere must have all of the moisture and water vapour removed before loading to prevent an unsafe reaction with the cargo. To achieve this, the cargo tank is dried, generally with the introduction of nitrogen or with specially dried air, and then the tank and associated piping and equipment are filled with moisture free gas with a dewpoint of -40°C or less. The use of a dewpoint meter may significantly reduce the time required for this operation. The tank atmosphere conditions that need to be maintained should be established prior to loading, and maintained during loading, the sea voyage and during discharge. Padding and blanketing Padding, or blanketing, is a term used to describe how a cargo is protected from moisture i n the atmosph ere above the cargo by the application of a 'pad' or ' blanket' of nitrogen. This process is usually performed after the cargo has been loaded, using nitrogen at low pressure and at a low flow rate. Padding does not replace all of the air in the tank but is designed to provide a layer of nitrogen above the surface of the cargo. A safe practice is to i ntroduce th e nitrogen directly into the cargo tank ullage space or via the ship's cargo line, preferably using the ship's equipment and gas supply. Shippers may, however, specify that nitrogen of a known purity is used and supplied from shore. In these circumstances it is preferable that the nitrogen is supplied to the tank prior to loading so that a layer of nitrogen remai ns above the surface of the cargo after loading is complete. Alternatively the nitrogen may be applied via the ship's venting system after loading. However, should it be necessary to supply nitrogen from the shore termi nal after loading then it should preferably be supplied direct to the ullage space of the tank and not via the cargo loading line. This is best achieved by connecti ng the nitrogen hose direct to a small diameter ball valve fitted to the vent line or to the

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tank hatch. The operation should be stopped when a slight over pressure exists withi n the ullage space which is less than the tank's PN valve's opening setting. The vapour space in a loaded tank is usually small, so over pressurisation can occur very suddenly if not monitored careiully. Should it be necessary to supply nitrogen via the cargo line then the following precautions should be observed : Nitrogen (or any other gas) flow should never be controlled through th e main cargo or vapour line manifold valve. Instead, flow should be controlled through a small diameter line fitted with a ball valve, enabling the vessel to control the flow of nitrogen effectively; In all cases, the delivery rate of nitrogen (or any oth er gas) should not exceed the operational limits of the tank venting system;

It is preferable for the shore to provide a dedicated pressure control system fitted at the junction between the shore inlet line and the ship to manage the pressure and flow coming on board the vessel; Oxygen levels must be mai ntained at or above the minimum level required by oxygen dependent inhibitors used w ith certain self-reactive chemical cargoes (e.g. styrene and ac.rylonitrile). In such cases, padding (or blanketing) with nitrogen (either at the berth or during transit) should be strictly controlled in compliance w ith the inhibitor certificate. Using nitrogen during discharging and tank cleaning operations should also be strictly controlled to ensure the oxygen level is maintained within the appropriate limits. Similarly, bubbling nitrogen through these products should be avoided, as this could drive oxygen out of the product; and Monitoring of the ullage space should be carried out at regular intervals during the voyage to ensure that the correct atmosphere is being maintained. For additional information regarding the loading of inerted tanks refer to Section 7.4.5.

6.Z9

DANGERS OF PRESSURISED LOADING A compressed gas is sometimes used by a terminal to press products to the vessel. Due to the significant risk involved, this practice should be limited to cases where no alternative transfer method is available such as the emptying of railway wagons. This method of cargo transfer carries a very real risk of an accidental over pressurisation of the vessel's cargo tank. The pressures used for these operations vary, but can range between 2.5 and 5 bar and the compressed gas can be delivered at a high rate. The critical stage is when the discha rge tank empties allowing a surge of compressed gas to flow into the ship's tanks. Over pressurisation of a closed tank can occur i n seconds, especially when the distance from the manifold to the tank is small or the vapour space in the ship's tank is limited. For this reason it is essential that agreement is reached with the shore terminal at the pre-transfer meeting concerning how this risk will be managed. Due to the risk associated with pressure loading the following precautions should be i ncluded in procedures for carrying out this operation: A crew mem ber stationed at the manifold will be best placed to detect and react (using valve control) to any indication that the flow in the system has changed from a liquid to a gas; Pressure loading to be supervised by a responsible officer; Ensuri ng that effective communications are established with the terminal staff in charge of the pressure loading operation; Ensuri ng that the PN valve is fully operational; Providing the cargo loaded is non-toxic, non-corrosive and non-flammable, one of the tank hatches should be left unsecured so acting as a secondary means of relievi ng a surge in tank pressure. Terminal permission may be required; Monitoring pressure i n the tank; Ensuri ng that tank pressure alarms are working and, if none are fitted, installing temporary pressure gauges;

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If the pressure alarm sounds, stopping the transfer immediately; and Closing the manifold valve immediately on completion.

6.ZlO TOPPING OFF PROCEDURE Topping off is a critical period and it is essential that sufficient personnel are available to manage the operation, especially when loading a number of tanks at a high loading rate. Care must be taken as tanks become full, especially when loading a product into more than one tank simultaneously. Closing down one tank will increase the loading rate to other tanks on the same loading system. Tanks that have been topped off should be properly isolated from tanks still being loaded. Relying on only one valve to segregate a tank that has completed loading from one that is still loading should be avoided. The loaded tank should be checked regularly to ensure that the level is not increasing. When loading more than one tank the loading rate should gradually be reduced as tanks in the system are topped off so that, when the last tank is due to be completed, the loading rate is manageable. When nearing completion of loading, the shore should be notified and, if necessary, the loading rate reduced still further.

It is recommended that no tank is loaded beyond 98% of its capacity by volume.

The following guidance should be complied with: When planning cargo operations, attention must be paid to allow sufficient time between topping off different tanks; Topping off procedures must be agreed with the terminal or the transshipment vessel. The agreed notification time for slowing down and maximum topping off rate required by the ship must be recorded in writing in the checklist during the pre-loading meeting; There should be sufficient personnel on deck at all times during topping off operations, with consideration for extra personnel being available if required; The topping off sequence should be taken into account when planning the rigging of lines and hoses; Simultaneous topping off of different parcels should be avoided. If necessary, the loading of one or more grades must be slowed down or stopped; The duty officer should have full authority to stop or slow down the pumping rate if, for any reason, there is doubt concerning the safety of the operation. Loading should only resume at the planned loading rate when the duty officer is confident that the situation i s under control; A request from the ship to reduce the loading rate should be confirmed by all available means. If a failure to reduce the loading rate is noted, the duty officer should not hesitate to activate the shore emergency shutdown procedure (as agreed during the pre-loading conference) before a critical situation develops; In the event of communication failure between the ship and the loading facility, or between essential ship's staff, during or near the topping off operation, loading should be immediately stopped until such communication has been re-established and the manifold valve closed; In the event of a problem with the remote cargo monitoring system, all operations should be stopped until the system is operational or manual monitoring procedures are established. In this case the Master or designated responsible officer should be notified; High level alarms should never be used for topping off purposes. Topping off ullages must be calculated before the start of the loading operation and revised with more accuracy when final trim is known; and If the overfill alarm is activated, loading of that tank should be immediately stopped.

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6.Z11

SAMPLING AND GAUGING There should be a delay of 30 minutes after loading a tank containing static accumulator cargo before sampling and gauging. This is to .allow the settling of gas bubbles, water or particulate matter and subsequently the relaxation or dissipation of static electricity.

With the exception of toxic and flammable cargoes, and following the outcome of a risk assessment, open sampling/gauging may be carried out. Sampling and gauging under closed conditions will ensure that personnel are not exposed to the cargo or its vapours. When sampling and gaugi ng tanks, shore i nspectors should always be accompanied by a responsible officer. Shore personnel or surveyors should not be allowed to draw samples without a member of the ship's crew being present. Most chemical tankers have closed gauging and sampling capability. Unless the ea rgo presents no risk to personnel, all requests from shore personnel to sample and gauge cargo from an open hatch should be refused. The company may develop procedures for groups of cargoes that are suitable for open sampling and gauging. Sampling bottles should be clean to ensure that the sample is not contaminated by impurities. When sampling and gauging, the following should be considered: Appropriate PPE must be worn; The characteristics of the chemical should be considered and the MSDS sheet and the IBC Code consulted; Samples should be kept in either clear or amber glass bottles with secure lids; Manufacturers' guidance for maintenance of sampling equipment should be followed; To avoid contamination, sampling equipment should be kept clean and dry; Closed sampling equipment must be tested for electrical continuity and earthed prior to introduction i nto tanks; Anti-static precautions must be taken and cargo relaxation periods observed when dealing with static accumulator products; MSDS should be kept with stored samples; and All sampling and gauging lines should be made of non-static generating material. Requirements for taking samples vary. However, it is common for samples to be requi red as follows: Manifold sample at commencement of loading (from each shoreline, if more than one); Pump stack sample; First foot sample from each tank duri ng loading; Final sample from each tank after loading; Composite sample of all tanks after loading; All tanks before discharge; and Composite sample before discharge. All samples drawn should be clearly labelled and, together with any samples drawn by the shore inspector, should be securely stored in the vessel's cargo sample store.

In order to avoid the dangers of static electricity, all sampling anct gauging lines should be made of non-static generating material.

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For information regarding liquid level gauges also see Section 5.3.4.

6.Z12 SAMPLE MANAGEMENT After completion of loading or before discharge commences, samples of the cargo should be obtained under supervision of the duty officer, the shipper's surveyor and a representative from the shore installation. The sample should be stored in the sample locker (see Section 6.7.14). Each sample should be closed with a numbered seal. It is recommended that the sealing of samples is conducted by a surveyor who should confirm in writing: Grades sampled; Quantity of samples; Point that sample(s) were drawn from; and Seal numbers. Marking of samples Sample bottles should be clearly marked with: Date and time of sampling; Port; Type of sample e.g. manifold, final from tank after loading, tank before discharge; Grade; Tank number; Manifold number; Name/rank of person taking the sample; USCG Compatibility Number (if appropriate); and MARPOL Category (X, Y, Z or OS). A log should be kept with the seal reference number and date of all samples, as well as the date of final disposal. Retention of sampl es All samples should be kept in the sample locker for a ti me to be determined by the company. Disposal of samples Cargo samples should be disposed of as required by the SMS. When cargo samples are disposed of ashore, an entry should be made i n the Oil Record Book Part II for Annex I products or in the Cargo Record Book for Annex II products. This record should include: date, place, number of samples, quantity per bottle and a reference to the delivery receipt. Inhibited samples Inhibited samples, which should be checked regularly for signs of polymerisation, should only be retained for the period that the i nhibitor remains active, as stated in the inhibitor certificate.

6.Z13 SAMPLING SYSTEMS During all sampling, appropriate PPE should be worn.

Closed systems Closed systems must be used for inerted or toxic cargoes and as designated in the IBC Code as requiring closed venti ng and/or restricted gauging.

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Closed sampling employs the same vapour lock system to take cargo samples as is used for tank gauging equipmen t. Exposure to cargo vapours is eliminated when properly used. Various types of sampling receptacles can be attached to a closed gauging device i n order to obtain bottom samples or represen tative samples drawn from various levels within the cargo (see Figure 6.2a).

Figure 6.2a - Closed Sampling

Figure 6.2b - Closed Sampling

Another type of closed sampling device is one in which cargo flow is directed from the fixed pipi ng system to an assembly where it is injected into a sealed sample bottle, see Figure 6.2b. Restricted systems Unless using a fully closed system, a small amount of vapour w ill be released and appropriate precautions including the setting of safety zones and use of PPE should be taken (see Section 5.3.4). Open system An open system uses a sample catching device lowered into a tank via an open hatch. The device may consist of a sample bottle lowered directly into a tank o r it can be some other open container w hich is then used to transfer samples to bottles at the cargo deck level. The IBC Code does not designate which sampling system should be em ployed for various cargoes. However, it is recommended that ship's staff align their sampling procedures with those required for gauging systems found in the IBC Code. An open sampling system should only be used for cargoes that are not flammable or toxic and that are designated i n the IBC Code as bei ng suitable for open venti ng and/or for open gauging.

6.Z14 SAMPLE STORAGE Chemical tankers are required to store a w ide range of cargo samples. The IBC Code requires that the storage of samples must be w ithi n a purpose built storage locker. The sample locker must be designed and built to ensure that sample bottles are securely stored and protected from damage and that the space is adequately ventilated and fitted with flame arresters. Fire-figh ting equipmen t should be readily available. The sample store should be a dedicated locker, resistant to the different liquids th at will be stowed in it and sited within the cargo area. The sample locker sh ould separate ch emicals th at react dangerously with one another, and must only be used for the storage of cargo samples.

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Figure 6.3 - Sample Storage

6.ZlS BALLASTING AND DEBALLASTING IN PORT Chemical tankers frequently ballast and deballast during cargo operations in order to maintain th e vessel in an upright and stable condition and to prevent undue stresses on the hull. Ballast transfers can be kept to a minimum by careful planning and may have to comply with regulatory restrictions on the discharge of ballast in port. When emptying ballast tanks, cargo vapours may be drawn into the tank through openings. Ballast tank lids should therefore be kept closed when both cargo and ballast are being handled simultaneously. Upon completion of ballasting or deballasting all tank openings used should be closed and secured (see Section 4.6.) 17

6.Z16 CLEARING SHORE PIPELINES General On completion of loading, the shore pipelines are usually cleared by the use of compressed air or inert gas. Prior to th e commencement of any line clearing to the vessel, the ship should check that there is sufficient space available in the tank to accommodate the contents of the shore line. The dangers of utilising compressed air or nitrogen to clear lines should be carefully considered (see Section 7.4.9). Pigging Shore terminals may request use of a rubber or foam ' pig' of the same diameter as the pipeline in order to ensure that the shore line is cleared effectively of all product. The 'pig' is forced through the line by a compressed gas, usually nitrogen for volatile products, and on arrival at the dock side the pig enters a trap. At this stage the compressed gas in the line is released to the ship in a sudden surge, and this can lead to a rapid over pressurisation of the ship's tank. Pigging the shore line to the ship's tanks should, wherever possible, be avoided due to safety risks to personnel and to the ship.

17 A.t the time of writing the IMO 8alast water Management Ccnvention has not entered into force but is expected to do so soon. Ships should also ensure compiance with any nat>Onal °'regional ballast water management requirements.

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If there is no alternative then pigging operations can be permitted, but only provided that a well planned procedure has been jointly agreed at the pre-transfer meeting (see Section 6.5.1). The planned procedure should address the requirements described below.

The terminal must follow pre-agreed procedures if pigging is to be used to clear shore lines, particularly when they contain toxic. corrosive or low flash cargoes.

During a line clearing operation it is important that terminal staff react promptly when the ' pig' is caught in its trap, in order to avoid a surge of compressed propelling gas entering the ship's tank. Any pigging increases the risk of injury or damage. A risk assessment must be conducted. In addition to PPE requirements tleing identified the following measures should be implemented: Pigging operations should always be supervised by a responsible officer; Effective communications must be established with the terminal staff in charge of the pigging operation; That there is sufficient space in the ship's tank for the quantity of product being cleared from the shore line; That the PN valve is correctly set and free to move; One of the tank hatches should be left unsecured so acting as a secondary means of relieving a surge in tank pressure (terminal permission may be required); Pressure in the tank is monitored. Tank pressure alarms must tie working and if none are fitted temporary pressure gauges should be installed;

If the pressure alarm sounds, pigging must be stopped immediately; A crew mem ber must be stationed at the manifold for valve control; and Immediately on completion the manifold valve must be closed. Static accumulating cargoes

If it is necessary to clear lines of a static accumulating cargo, only an inert gas should be used (never compressed air). The amount of gas allowed to enter the ship's tank should be kept to a practical minimum.

Compressed air should never be used to clear lines of a static accumulating cargo.

Inhibited cargoes

If nitrogen is used to clear the cargo hose after loading a cargo treated with an inhibitor that is dependent on oxygen, great care should be taken to minimise the volume of nitrogen entering the cargo tank. Bubbling nitrogen through the liquid in the tank will deplete dissolved oxygen w ithin the product which could adversely affect the effective working life of the inhibitor.

6.Z17 COMPLETION OF TRANSFER On completion of transfer and line clearing operations the manifold valves should be closed and the shore terminal advised. After steaming, blowing or draining of lines is completed, all valves in the system should be closed .

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6.Z18 DISCONNECTION OF CARGO HOSES After the transfer operations are complete, effective procedures should be followed to minimise residues remaining in the section of line between the vessel's manifold valve and the shore connection. Disconnection should only take place after the draining of cargo residues and the relief of any pressure. Disconnection of the hose or cargo anm at the ship's manifold is an occasion when the cargo containment system is deliberately breached. Although hose disconnection is a routine operation, it should always be regarded as comparable to opening up any other cargo pipeline on deck. Personnel engaged in hose disconnection should wear Personal Protective Equipment appropriate to the hazards of the cargo involved, which might include a full chemical resistant suit and breathing apparatus.

Care should always be taken to avoid incompatible cargoes being mixed in cargo and stripping lines, slop tanks, drain tanks and manifold d r ip trays.

6.Z19 CARGO UNLOADING General Cargo unloading is an operation fully under the control of the ship. Unloading rate Commencement of unloading should be at a slow rate until it has been verified that the cargo is being loaded into the correct shore tanks, that there are no leaks in the system and that all monitoring systems are f unctioning correctly. On the satisfactory completion of initial checks, the unloading rate can be increased to the maximum rate agreed at the pre-transfer meeting. Checks during unloading At regular intervals throughout the operation, checks should be made to ensure there are no leaks and that tanks are being discharged according to the agreed transfer plan. Remote read outs from tanks should be checked for accuracy by utilising the closed gauging equipment. Full tanks should be regularly checked to ensure that no cargo is leaking. Similarly empty tanks should be regularly checked.

6.Z20 INERTING AND TANK ATMOSPHERE CONTROL DURING UNLOADING For cargoes that need to be kept inerted, inert gas, usually nitrogen, is used to ensure the atmosphere in a cargo tank remains non-flammable as the tank empties. The oxygen content should be kept below 8% and a slight over pressure maintained to prevent air being drawn into the tank (see Section 4.5). Guidelines for inerting operations and the dangers of using inert gas and nitrogen are described in Chapter 7.

6.Z21 SWEEPING OF CARGO RESIDUES General After the carriage of animal and vegetable oils, manual sweeping of the cargo tanks may be necessary in order to push the semi-liquid residues towards the pump suction to complete the discharge. Despite the natural origins of such cargoes, it is essential that the ship's enclosed space entry procedures are complied with on every occasion that personnel are sent into an enclosed space (see Chapter 9).

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The tank should be mechanically ventilated for at least 1 hour, concurrently with discharge, to ensure its atmosphere is safe for entry before sweeping begins. The heating coil valves should be closed prior to the entry of perso nnel to avoid the risk of burns. The control of heating coils will be dependent on the ambient tem perature at the time. The requirements for tank entry and atmosphere testing in Chapter 9 of this Guide should be complied w ith, and an enclosed space entry permit issued before any personnel enter the tank. Adequate safe lighting should be provided in the tank. An additional risk of sweeping tanks is that animal and vegetable oil makes all surfaces very slippery and therefore all those who enter the tank should be advised to take extra care, e.specially on ladders and platforms. In addition, viscous oils are heated to high temperatures and there are dangers that persons working in the tank may be adversely affected by the heat, especially when there are high ambient temperatures. Prior to commencing sweeping operations the crew should be briefed on the dangers involved. The following guidelines should be complied w ith : An experienced person should be appointed to be the leader of the sweeping team. Their role w ill be to coordinate the w ork and look o ut for the safety and welfare of the t eam; The team leader should be able to com municate effectively w ith the person stationed at the entrance to the tank; All members of the team should be encouraged to look out for the wellbeing of their fellow team members;

If, at any time, a person finds it hard to breath or feels unwell due to the effect of the heat o r any other cause, they should alert the team leader who w ill raise the alarm . The person should vacate the space as soon as possible by w hatever means is practical in the circumstances; and Proper PPE should be worn (see PPE matrix in Appendix 10, and Section 3.1 1) . Ventilation should continue during the sweeping operation. A responsible person should remain in attendance at the tank entry hatch throughout the sweeping operation, keeping the personnel within under observation and monitoring the oxygen level within the tank .

If at any time the oxygen level falls below 21 % , the tank m ust be vacated until the oxygen level has been restored by ventilation. Shore work ers In some ports, shore workers are employed to carry out the sweeping of tanks. Th ese personnel may be unfamiliar with the vessel and may have never been o n a ship before. The responsibility for the safety of these shore personnel rests with the ship. Prior to the commencement of any sweeping operations the ship's safety procedures for entering enclosed spaces should be demonstrated. The shore staff should be left in no doubt that the responsibility and control of all sweeping operations will be under the management of ship's crew (see Section 3.6).

6.Z22 COMPLETION OF DISCHARGE Stripping

It is essential to reduce the cargo residue in a tank to the minimum attainable. Tanks should be stripped according to the requirements of the Procedures and Arrangements (P&A) Manual using the designed stripping system. On completion of the stripping operations the manifold valve should be closed.

If for any reason the tank's content cannot be stripped as per the P&A Manual the tank should be prewashed and the slops discharged ashore.

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Cargoes requiring prew ash Prior to the vessel arriving in port it should be established h ow cargoes requi ring a prewash are to be handled. Providing the terminal can accept the prewash residues the vessel must carry o ut the operations in accordance with the P&A Manual.

6.8

CARGO CARE DURING THE VOYAGE

6.8.1

TANK INTEGRITY Regular checks of the tanks and the surrounding spaces should be carried out to en sure th at there has been no leakage of cargo into adjacen t tanks, ballast tanks, void spaces an d cargo pumprooms. The condition and proper securing of all tank openings should be checked regularly to ensure that the tanks are effectively sealed against contamination by the outside environment and to ensure that, w here required, a positive pressure of inert gas can be maintained.

6.8.2 TANK VENTING Tank vents can become blocked by co ndensi ng cargo vapours, ice and by heated cargoes entering the vent lines and solidifying. The risk of blockage increases during heavy or adverse weather condit ions. PN valves should be checked regularly to ensure they are working correctly, ea re bei ng taken to protect personnel agai nst exposure to cargo vapours. If heat tracing lines are firtted to preven t icing they sh ould be used . Most chemical tankers have pressure sensors fitted as a secondary protective measure agai nst tank over or under pressurisation and these can also be used to check that the tank venti ng system is functioning correctly.

6.8.3 TEMPERATURE CONTROLLED CARGOES Cargoes that need cooling or heating must be monitored daily and a temperature log maintained . Temperature monitoring is usually by a remote read out in the cargo control room. If heated cargoes and h eat sensitive cargoes are carried in adjacent or near adjacent tanks, both should be monitored for any temperature changes. It may someti mes be necessary to monitor cargo temperatures using the closed gauging system. Should personnel be required to monitor tem peratures manually precautions should be taken to prevent them being accidently exposed to the cargo or its vapours. In adverse weather considerable pressure surges can build up in a cargo tank and it may be necessary to alter the ship's course so as to minimise the ship's movement w hile temperatures are bei ng taken. Where an observation tank is fitted between the heati ng return lines and the en gine room the quality of condensed w ater returns from the coils can be viewed through a sighting window , and contamination of the water sh ould be detectable.

6.8.4

INHIBITED CARGOES Some cargoes are liable to self-react under certain conditions (see Section 1.6 and Appendix 6). The temperature of cargoes that may self-react sh ould be closely monitored. Unexpected changes of temperature are an early i ndicator of a possible self-reaction. Should the tem perature rise be in excess of what is expected, taking into account the ambient condit ions and the temperature of adjacent cargoes, then this should be treated as an emergency and handled accordingly (see Chapter 10).

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A polymerising cargo will generate a lot of heat with a rapid rise in temperature so the vessel should always have a contingency plan ready to jettison the cargo.

With inhibited cargoes, the precautions and limitations described in th e inhibitor certificate should be carefully observed. If control of the tank atmosphere is being used, ullage spaces should be monitored regularly to ensure that the correct atmosphere and over pressure are being mai ntained. Most inhibitors are not themselves volatile, so they do not vaporise with the cargo and are unlikely to be present in cargo vapours. Polymerisation may therefore occur where cargo vapours condense. Such places as i nside vent valves and flame arresters should be regularly inspected, and any blockage by solid polymers promptly cleared. A cargo that contains an oxygen dependent inhibitor should not be inerted before loading or during carriage. If there is a requirement to inert the cargo this should only be done before unloading.

6.8.S MAINTAINING AN INERT ATMOSPHERE DURING THE VOYAGE A positive pressure of inert gas should be mai ntained in the ullage space of an inerted cargo tank at all times in order to prevent the possible ingress of air. If the pressure falls below the set level of the low pressure alarm, action should be taken to repressurise the tank with i nert gas. Pressure loss is normally associated with falling air and sea temperatures. The oxygen level in the ullage space should also be monitored regularly to ensure that it remains below 8%. Should a positive over pressure be difficult to maintain this would indicate that there is a leak w ithin the tank's containment system. Checks should be made for faulty PN valves and incorrectly sealed tank hatches. Other connections to the tank should also be checked and, if necessary, tightened or adjusted. Where the inerting or padding of the tank is by nitrogen cylinders provided from shore there should be sufficient capacity available for the whole voyage. Guidelines for inerting operations and the dangers of using i nert gas and nitrogen are described in Chapter 7.

6.8.6

BALLASTING CARGO TANKS Sometimes it may be necessary to load ballast water into cargo tanks for stress and stability reasons or to improve a vessel's sea keepi ng qualities i n h eavy weather. Cargo tanks to be ballasted should be clean or, if this is not possible, only tanks which have contained a non water reactive cargo should be used. Ballasting a cargo tank that has not been cleaned may cause flammable, toxic or corrosive vapours to be expelled. Precautions will need to be taken to protect the crew. Ballasting operations should be carried out in compliance with MARPOL, the Balla.st Water Management Convention (when it enters into force) and any local requirements a.s described in Chapter 4.

6.9

SHIP TO SHIP TRANSFER

6.9.1

GENERAL The ship to ship (STS) transfer of cargoes carried on chemical carriers is a frequent operation. Guidance is provided in the Ship to Ship Transfer Guide for Petroleum, Chemicals and Liquefied Gases (referred to below as th e STS Guide) published joi ntly by ICS, OCIMF, SIGTIO and CDI.

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The STS Guide provides guidance for STS transfer operations undertaken both 'at sea' and 'in port'. The term at sea is intended to indicate offshore waters or partially sheltered waters. It should be noted that an STS transfer operation at sea may be conducted withi n the jurisdiction of a national government. In such cases, reference should be made to applicable regulations and the possible need to obtain local approval for the activity. STS transfers undertaken at sea may pose specific issues that need to be addressed as they often take place i n locations that may be beyond the assistance of normal port services. The scope of the STS Guide when compared with that of earlier editions has been expanded to take account of in-port transfers. These may involve transfers to or from a vessel at anchor, moored to buoys or alongside, and may involve multiple vessels some of which, particularly in the chemical trade, may be of small size and include manned and unmanned barges and estuarial craft. Appendix B of the STS Guide i ncludes guidance for chemical tankers conducting ship to ship transfer operations specifically when in port. The STS Guide also provides advice about special equipment necessary, and preparation of conti ngency plans for dealing with emergencies. In general, observance of the procedures followed when handling cargo alongside a termi nal will ensure safe ship to ship transfers. However, an important additional task is careful pre-planning of the operation, noting instances where shore provision of materials or labour for handling equipment is normal termi nal practice, and identifyi ng on board or external sources of material or personnel to pertorm those duties during the ship to ship operation.

6.9.2

RESPONSIBILITY In general, it is the responsibility of the ships' operators and agents to obtain any permission necessary for a ship to ship transfer operation, especially if the transfer area is within the jurisdiction of a port authority. The checklists in Appendix E of the STS Guide should be used at the planning stage to ensure compatibility of ships and their cargo handling equipment. The general principles of a transfer, the area in which the transfer will take place, and the compatibility of the ships should follow the advice in the STS Guide, with safety always the primary consideration. Ship operators or the local agent should advise the Master about documentation requirements, especially Customs documentation, well in advance of the transfer. It is normal for the quantity transferred to be agreed between the Masters of both ships in accordance with operators' instructions. When preparing for a ship to ship transfer, the two Masters involved should agree at the earliest opportunity on every aspect of the transfer procedure, and agree which person will be in overall advisory control of the operation (this may be one of them or an experienced STS superintendent). At all times, however, each Master will remain fully responsible for the safety of their own ship, its crew and its cargo, and must not permit safety to be jeopardised. All involved parties should be advised as to the identity of the person in overall advisory control.

6.9.3

COMMUNICATIONS The need for a common language of communication is most i mportant. Satisfactory communication between the two ships involved is an essential requirement for a successful ship to ship transfer operation. Neither approach and mooring, nor unmoori ng, should be attempted until satisfactory communications are established, and initial but essential information is exchanged. If duri ng cargo operations there is a breakdown of communications on either ship, all operations should be suspended until they are satisfactorily restored.

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6.9.4

NAVIGATIONAL WARNINGS The person w ith overall advisory control should arrange for the broadcast of a navigational warning about the transfer, and should arrange for its cancellation on completion of the operation.

6.9.5

WEATHER CONDITIONS AND LIMITATIONS It is impractical to lay down the limits of weather conditions under which STS transfer operations can safely be carried out. All available weather forecasts for the area should be obtained before the operation begins. Thus any decision to proceed w ill be taken in the light of best available knowledge.

6.9.6

PRE-TRANSFER PREPARATIONS ON EACH SHIP Preparations on each ship in readiness for the operation, the approach of the ships to each other, berthing and mooring of the ships and safety procedures when alongside, should be conducted i n compliance with the STS Guide. When prepari ng cargo loading and discharging plans, due regard should be given to ensuri ng that adequate stability is maintained, hull stresses remain within seagoi ng limits, and that free surface effects are kept to a minimum throughout. The cargo operation should be planned and agreed between th e two ships, and should i nclude the following i nformation, where applicable: Quantity of each grade of cargo to be transferred, and the sequence of grades; Cargo data from MSDS; lnerting requi rements when applicable; Inhibitor requirements when applicable; Details of cargo transfer system to be used, number of pumps and maximum pressure; Initial, maximum and topping off pumpi ng rates. The discharging ship should be informed by the receiving ship of the flow rates required for each of the different phases of the cargo operation; Notice of rate change, and transfer shutdown procedures. If variations in transfer rate subsequently become necessary due to circumstances on one ship, the other should be advised accordingly; Emergency and spill contai nment procedures; Watch or shift arrangements; Critical stages of th e operation; and l ocal and national rules that apply to the transfer.

6.9.7

CARGO TRANSFER OPERATIONS When th e two ships are securely moored, and before cargo transfer commences, th e pre-transfer checks should be satisfactorily completed (C hecklist 4 or 6 i n the STS Guide). In addition, attention should be given to completion, as far as practical, of th e appropriate Ship/Shore Safety Checklist (see Appendix 3 of this Guide). Hose strings should be of sufficient length to avoid over stressing and chafing throughout th e cargo transfer. To establish th e correct hose length, changes i n relative freeboard and ship movemen t should be taken into account. Only hoses i n good condition and suitable for the cargo to be transferred should be used. The agreed transfer rate should not exceed the manufacturers' recommen ded flow rates for the cargo hoses. Vapour return and vapour balance between ships duri ng an STS operation can be problematic. Its main advantage will be to limit the need for vapour release to atmosphere, and crew exposure to the vapour. But attention must be given to provision of a flame arresting arrangement. For some cargoes specified in the IMO Codes, vapour return is mandatory, and STS operations will be dependent on the provision of correct vapour return equipment.

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Throughout cargo operations, th e discharging ship and th e receiving ship should each station a responsible person at the cargo manifold area to observe the hoses and to check for leaks. In addition, throughout the cargo transfer, the discharging ship should station a responsible person equipped with a suitable radio at or near the cargo pump controls to take action as required. Regular transfer rate ch ecks and com parisons should be made between the two ships, and the results logged. Any differences or anomalies revealed should be carefully checked, and if necessary cargo operations should be suspen ded until the differences are resolved . During cargo transfer, appropriate ballast operations should be performed on both ships in order to minimise ext reme differences in freeboard, and to avoid excessive trim by the stern. Listi ng of either ship should be avoided, except as required for cargo tank draining on the discharging ship. Regardless of the type of ship, any ballast which is discharged overboard should be clean. All other ballast should be retai ned on board or transferred to the dischargi ng ship.

6.9.8

COMPLETION OF CARGO TRANSFER After completion of cargo transfer, all hoses should be drained into the receiving ship prior to disconnecting. Disconnecti ng of cargo hoses should receive careful attention, as it is a procedure not usually undertaken by ship's personnel. Cargo manifolds and cargo hoses should be securely blanked. The guidance in Section 5.14 should be noted. Relevant authorities, if any, should be informed of completion of cargo transfer and the anticipated time of unmooring. Any navigational warning issued should be cancelled.

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CHAPTER 7

INERT GAS AND NITROGEN SAFETY

7

INERT GAS AND NITROGEN SAFETY

This chapter addresses the use of inert gas, especially nitrogen, which is a routine operation on board chemical tankers. However, while inerting cargo tanks considerably reduces the risk of fire and explosion, inert gas, particularly nitrogen, can also pose serious safety hazards to the crew if not managed correctly.

7.1

Introduction

7 .2

Dangers of Nit rogen

7.3

Safe Operations Involving Nitrogen

7.4 7.4.1 7.4.2 7.4.3 7.4.4 7.4.5 7.4.6

lnerting Operations lnerting definitions Maintenance of an inert atmosphere lnerting tanks containing cargo lnerting empty tanks loading inerted tanks Maintaining inerted tanks during the voyage Maintaining an inert atmosphere during unloading Tank cleaning and gas freeing under inert conditions Nitrogen supplied from shore

7.4.7 7.4.8 7.4.9

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Zl

INTRODUCTION This chapter takes account of the 2014 amendments in SOLAS Chapter 11-2 regarding the use of inert gas (IG) on chemical tankers, which enter into force on 1 January 2016 (see also Section 4.5). The purpose of this chapter is to provide safety guidelines for the use of inert gas, particularly nitrogen. All inert gases are deficient in oxygen and therefore do not support human life. Conventional inert gas produced from a combustion process contains impurities which are usually detectable by smell. Nitrogen, however, is clean and odour free and an ideal inert gas for many applications. It has been used for many years on chemical tankers for cargoes required to be kept inerted by the IBC Code or for cargo quality control reasons. Compressed nitrogen is also used for line clearing and stripping operations, and for other maintenance tasks such as the 'purging' of deepwell pump cofferdams. With the introduction of large capacity nitrogen generators, inerting tanks with nitrogen can be extended to other cargoes and is increasingly being used to inert low flash cargoes to provide a safe tank atmosphere, especially while tank cleaning. Although nitrogen is referred to specifically in this chapter, the term inert gas refers to inert gases produced by either nitrogen generators or inert gas generators. See also Section 5.13 of this Guide.

Z2

DANGERS OF NITROGEN The air we breathe normally contains 78% nitrogen and 21 % oxygen with the remaining 1% made up of carbon dioxide and other gases. When breathing normally part of this oxygen is absorbed by the blood, inside the lungs, while carbon dioxide passes from the blood back into the air. If we breathe inert gas (nitrogen), both the normal oxygen and carbon dioxide levels in our blood are reduced as they are replaced by nitrogen. Carbon dioxide is essential in the blood to stimulate the breathing reflex. If nitrogen replaces carbon dioxide this reflex is inhibited and breathing stops. When nitrogen levels increase, oxygen in the blood is displaced affecting the exdhange of carbon dioxide, and the stimulation to breathe is reduced. When the oxygen concentration drops from 21 % towards 16%, pulse and breathing rates drop, and mental functions are impaired. Below 14% oxygen concentration people suffer abnormal fatigue, emotional upset, poor judgment, and faulty coordination. Further reductions result in nausea, vomiting, permanent heart damage and loss of consciousness. At about 5% oxygen concentration or below, a person will quickly fall into a coma, requiring emergency administration of oxygen to have any chance of survival.

Notices should be displayed at the gangway and in other locations, as appropriate, warning personnel when nitrogen generation and operations are taking place.

Like the air that we breath, nitrogen is colourless. odourless and tasteless and i s therefore undetectable to the human senses. As the stimulation to breathe is removed by the presence of nitrogen there are no physical warning signs that the atmosphere is dangerous.. Exposure to a high concentration of nitrogen is usually fatal unless immediate action is taken.

When any cargo tanks or associated spaces are being inerted no tank entry should be permitted. Should tank entry become necessary, all inerting should be stopped and tank entry procedures must be followed {see Chapter 9).

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The following risks to crews have been identified with operations involving the use of nitrogen: Accidentally entering an inerted tank particularly during busy port operations when some tanks may need to be inerted while others w ill necessitate entry by crew or shore personnel for cleaning and inspection purposes; Working in other enclosed spaces which are adjacent to inerted spaces that are not sufficiently or effectively isolated; Inhaling nitrogen when working near a tank where nitrogen is being displaced, for example when loading an inerted tank; Inhaling nitrogen from inerted tanks during tank cleaning, especially when portable machines are used; Inhaling nitrogen while working on cargo lines and hoses during and following line clearing operations utilising compressed nitrogen; and Working in machinery spaces where nitrogen generating equipment is installed.

Z3

SAFE OPERATIONS INVOLVING NITROGEN Crew members with particular duties associated with nitrogen operations should be fully briefed on nitrogen risks during the ' toolbox talk' referred to below. Appropriate PPE should be worn. Due to the dangers identified in Section 7.2 the following safety precautions should be implemented whenever nitrogen is used: The shipping company should have procedures to address the hazards of working with nitrogen, and the crew should be trained and familiarised with these procedures; Prior to work commencing, a toolbox talk should take place to ensure that all involved have been briefed regarding the job and required safety measures, including the use of appropriate PPE and personal gas detector equipment. Being informal, taking minutes of the meeting is not appropriate although a record of attendees may be made; Operations such as inerting some tanks w ith nitrogen while other tanks are being cleaned or prepared for inspection must be strictly controlled to avoid tank entry during i nerting operations. Company procedures should address all of the risks involved and ensure safety barriers and enclosed space entry procedures are followed at all times. Should tank entry become necessary, all inerting should be stopped and tank entry procedures must be followed (see Chapter 9); Areas where nitrogen operations are taking place should be restricted only to those crew members and shore personnel who are directly involved in the operation. Pers.onnel working in these areas should carry a personal oxygen meter; Crew and shore personnel should be aware that deck structures may create areas that can allow nitrogen to accumulate near nitrogen inerted spaces. This can result in an oxygen deficient atmosphere developing, especially if there is little wind to disperse the gas; Crew and shore personnel should be aware of the wind direction and should seek to remain upwind of outlet(s) whenever possible; Cargo tanks and other enclosed spaces inerted w ith nitrogen should be tagged with suitable weather resistant warning signs such as: "Danger Nitrogen -Do Not Enter!"; Nitrogen supply lines should be capable of being blanked so as to prevent the accidental inerting of a tank. Precautions should also be taken to ensure that nitrogen cannot enter the tank via cargo lines, vent lines or any other tank connections; Following unloading, tanks inerted with nitrogen should be kept closed and tagged until the tank has been cleaned, ventilated, and tested to ensure it is gas free and the oxygen level restored, and that the tank is therefore safe for entry. See also Chapter 8 of this Guide;

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Access to the nitrogen generating machi nery space should be controlled with oxygen alarms and emergency escape breathing apparatus provided; and Some vessels are provided with tanks to store nitrogen i n liquid form. This requires a storage temperature of -196°C and therefore handling presents a low temperature hazard. Skin contact with liquid nitrogen can rapidly result in frostbite. Personnel liable to h ave contact with such storage facilit ies and associated systems should wear appropriate PPE to protect against this risk.

Z4

INERTING OPERATIONS

7.4.1

INERTING DEFINITIONS Inert gas An inert gas is low in oxygen and therefore incapable of combustion. The SOLAS regulations specify that an inert gas being supplied should contain no more than 5% oxygen. This will enable a tank atmosphere's oxygen content to be maintained below 8%. Inert gas can be produced utilising the exhaust from a burning gas or diesel oil in an inert gas generator, or by nitrogen generators. Due to quality issues most chemical tankers utilise nitrogen, supplied by either on board systems or from the shore. Nit rogen is also the required inerting medium under SOLAS Chapter 11-2, Regulation 16.3.3 (see Section 4.5).

lnerting lnerting is the displacement of ai r from a previously clean and gas free tank to create an inert atmosph ere within the tank. lnerting ensures the tank atmosphere is incapable of supporting com bustion by reducing the oxygen content. l nerti ng w ith nitrogen is also carried out to reduce the moisture content of the tank atmosphere for cargo compatibilit y and quality control reasons.

Padding ' Padding' means fi lling and maintaining the cargo tank and associated piping system with an i nert gas, or other gas, vapour or liquid, in order to separate the cargo from air.

Purging IMO defines 'purging' as the introduction of inert gas i nto a tank which is already i n an i nert condition with the object of f urther reducing the oxygen content; and/or reducing the existing hydrocarbon or other flammable vapour content to a level below which combustion cannot be supported if ai r is subsequently introduced into the tank. Purging utilises inert gas to reduce the concentration of hydrocarbon or other flammable vapours in the cargo tanks to less than 2 % by volume. The term purging is also used i n the chemical tanker industry to describe the process of replacing the tank atmosphere in order to reduce oxygen content or dewpoint.

Topping up During the voyage natural ' breathing' of the tank via the vent system, due to changes in ambient conditions or to the motion of the ship, will cause the oxygen level to rise. 'Topping up' is the use of inert gas to restore the tank atmosphere to the required oxygen content .

7.4.2

MAINTENANCE OF AN INERT ATMOSPHERE Chemical tankers transporti ng low flash point cargoes may be requi red by !MO regulations or the com pany's SMS to mai ntain tank atmospheres in an inerted condition. Additional requirements exist for particular cargoes to be kept inerted for cargo quality. The protection provided by an inert gas system depends on the proper operation and maintenance of the entire system. It is particularly important to en sure th at non-return barriers function correctly so that there is no possibility of cargo vapour o r liquids finding their way into machinery or other spaces via the inert gas distribution system. See also Section 4.5 of this Guide.

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7.4.3

INERTING TAN KS CONTAINING CARGO When SOLAS requirements require tanks containing cargo to be inerted prior to discharge as referenced under Section 4.5 of this Guide, inert gas should be introduced into the tank through the distribution system while venting vapours in the tank to atmosphere. This operation should continue until the oxygen content is at o r below 8% by volume.

It should be noted that the vapours vented during this inerting process may be both flammable and toxic (see Section 7.3).

7.4.4

INERTING EMPTY TANKS When the cargo requires an inert atmosphere, inert gas should be introduced into the empty tank through the distribution system while venting the air in the tank to atmosphere. This operation should continue until the oxygen content is at or below the value required for the cargo. In theory, if the entire existing atmosphere in a tank could be replaced by an equal volume of inert gas the resulting tank atmosphere would have the same oxygen level as the incoming inert gas. In practice, however, a good deal of mixing takes place during the exchange, so that a volume of inert gas equal to several tank volumes must be introduced into the tank before the desired result can be achieved (see Section 7.3). Dilution method Dilution takes place when the incoming inert gas mixes with the original tank atmosphere to form a homogeneous mixture throughout the tank so that, as the process continues, the concentration of the original gas decreases progressively. It is important that the incoming inert gas has sufficient entry velocity to penetrate to the bottom of the tank, and a limit must therefore be placed on the number of tanks which can be inerted simultaneously. The tank atmosphere should be maintained at a positive over pressure of at least 0.07 bar, taking care to prevent any rise in pressure which could result in the lifting of the tank's PN valve (see Section 5.8). Cascade method The cascade inerting method is used to save time and to inert more than one tank simultaneously. The principle of inerting by cascade is to lead the inert gas through a series of tanks. When a nitrogen plant with sufficient pressure is used, several tanks can be lined up in series. The nitrogen is introduced by the vapour line to the first tank and exits via the cargo lines to the next. From the second tank the inert gas exits by the vapour line to the third tank and so on. This will have the effect that the tanks are inerted from top to bottom or from bottom to top. Where it is found that the pressure in the inert gas line is insufficient, particularly if more than two tanks are simultaneously inerted, only a primary (first) and secondary (second) tank should be inerted simultaneously. When the required levels of oxygen and hydrocarbons are reached in the primary tank, inert gas is stopped to that tank. The secondary tank then becomes the primary tank, and the next tank is lined up as the new secondary tank. Displ acement method Displacement depends on the fact that inert gas is slightly heavier than the existing air in a tank, so that when the inert gas enters the tank the existing air is displaced. When using this method it is important that the inert gas has a very low entry velocity to enable a stable horizontal interface to be developed between the incoming and escaping gases, although in practice some dilution inevitably takes place owing to the turbulence caused by the inert gas flow. The method generally allows several tanks to be inerted or purged simultaneously. Whichever method is employed, it is important that sufficient oxygen or gas measurements are taken to check the efficiency of the operations.

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Crew members should be aware of potential hazards of an oxygen depleted atmosphere in the vicinity of tank vents and outlets during inerting, especially if nitrogen is the inert gas being used.

7.4.5

LOADING INERTED TANKS Venting When loading an inerted tank, the inert gas displaced should be vented through the tank's venting system. On completion of cargo loading, the tank should be shut down so as t o ensure that an over pressure of inert gas is maintained. It may be necessary to restart the inert gas system to 'top up' the ullage space, to ensure that a positive pressure is maintained. Inert gas and cargo vapours on the cargo deck In still weather conditions, inert gas and vented cargo vapours can linger on deck, especially in the vicinity of vents. A chemical tanker's complicated cargo deck structure and equipment can trap pockets of inert gas or cargo vapour. Those working in the cargo area should be aware of and anticipate areas where nitrogen and reduced oxygen levels, as well as toxic and/or flammable vapours, may linger. Such potential areas should be identified and access to them restricted as appropriate (see Sections 7.2 and 7.3).

7.4.6

MAINTAINING INERTED TANKS DURING THE VOYAGE During the voyage the oxygen level of an inerted tank should be monitored daily and an over pressure of inert gas maintained. Should oxygen levels rise, or positive inert gas pressure fall, then the tank will need to be 'topped up' with inert gas. Some cargoes can release entrapped oxygen during the voyage which requires that the ullage space is closely monitored.

7.4.7

MAINTAINING AN INERT ATMOSPHERE DURING UN LOADING During unloading, inert gas is supplied to the tank to ensure that the atmosphere remains inert. It is important that the supply of inert gas exceeds the discharge rate of the cargo pump so that a positive pressure is maintained. Should the oxygen content of the inert gas supply exceed 5%, or should it not be possible to maintain positive pressure, then the unloading operation should be stopped until the situation can be restored. Should tanks need to be opened for gauging or sampling purposes then the tanks should be 'topped up' with inert gas prior to commencing or resuming unloading. The precautions described in Section 7.3 should be observed when opening tanks inerted with nitrogen.

7.4.8

TANK CLEANING AND GAS FREEING UNDER INERT CONDITIONS The precautions necessary when using inert gas during tank cleaning and gas f reeing operations are described in Chapter 8.

7.4.9

NITROGEN SUPPLIED FROM SHORE General Should it be necessary to obtain nitrogen from the shore for inerting purposes, it is essential that, at the pre-transfer meeting, agreement is reached concerning the flow rate and the pressure of the nitrogen being supplied.

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Although a slight over pressure is required to be maintained (usually no more than about 0.2 bar). it is usual for the shore nitrogen supply pressure to be far in excess of this figure. Particularly in the early stages of unloading, when the ullage space is still small, it is possible for the flow rate to exceed the tank venting capacity, and for an over pressure to develop.

It is possible to over pressurise and damage a cargo tank if the flow rate of nitrogen supplied from the shore exceeds the maximum design rated capacity of the P/V valve.

Controlling the supply of nitrogen Manifold valves should not be used to control the pressure and flow of nitrogen under pressure. This is because these valves are designed to manage the flow of liquids, and not gases. The shore nitrogen hose should be connected to a small diameter ball valve on the ship's manifold fitted with a pressure reducing device, together w ith a calibrated gauge. The flow and pressure of the nitrogen supply can then be controlled effectively and, should the pressure in the tank increase beyond an agreed amount. the supply can be immediately shut off. There should be direct communication with the terminal during the operation. Most chemical tankers are provided with pressure sensors for each tank and these should be used to provide an alarm should pre-set pressure conditions be exceeded. Providing nitrogen after loading When a product is being loaded through the cargo line system, the existing atmosphere in the tank can escape through the vent pipeline system that is dimensionally smaller than the cargo line system. This is because gases can flow at a much quicker rate than liquids as there is less friction and turbulence. However, when a gas is being introduced through the cargo line, especially a gas under pressure that will expand within the tank, the same condition does not apply, and the difference in sizes between the inlet and outlet can result in an over pressure developing.

If the pressure and volume of the gas is high enough it will physically agitate the cargo (especially highly viscous products). There is a risk that cargo may be forced out of the tank at the weakest point which could be the vent, a hatch or even by rupturing the tank. For cargoes not required to be loaded under closed conditions a tank hatch can be left unsecured so as to relieve any excess pressure that cannot be handled by the tank's PN valve alone (terminal permission may be required for this operation). For cargoes requiring closed loading or vapour return, tank hatches cannot be left open and therefore the application of nitrogen from shore has to be very carefully managed. The flow rate of nitrogen should not exceed the maximum venting capacity of the cargo tank's PN valve or, when utilising the vapour return system, the vapour handling capacity of the shore installation. lnerting empty tanks When shore supplied nitrogen is to be used for drying or inerting an empty tank that has been cleaned and gas freed, the volume of nitrogen required can be calculated as follows. Table 7 .1 shows indicative volumes of nitrogen that could be delivered in m3/hr depending on specific ship and shore delivery characteristics. Tabl e 7.1

164

200mm (8")

150mm (6")

100mm (4")

50mm (2")

25mm (1")

5.2 bar

106,000

55,000

20,600

4,000

740

3.4 bar

77,000

39,700

14,600

2,900

530

2,000

360

1,000

170

2.1 bar

53,000

27,400

10,300

0.7 bar

28,300

12,900

4,800

TANKER SAFETY GUIDE (CHEMICALS)

Table 7.2 provides an indication of the time that may be needed to receive gas into a tank at different pressures and hose sizes. The example used assumes a cargo tank of 1,250 cubic metres requiring four atmosphere changes, i.e. 5,000 cubic metres of nitrogen to flow through . Table 7.2 200mm (8")

150mm (6")

100mm (4")

50mm (2")

25mm (1")

5.2 bar

3min.

5~min .

15 min.

1 14 hrs.

7 hrs.

3.4 bar

1 'A hrs.

4 min.

7 Y2 min.

21 min.

2.1 bar

5 Y2 min.

11 min .

29min.

2 Y2 hrs.

0.7 bar

11 min.

24 min.

63 min.

5 14 hrs.

165

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CHAPTER 8

TANK CLEANING AND GAS FREEING

8

TANK CLEANING AND GAS FREEING

This chapter describes the safety precautions and best practice to be followed prior to and during tank cleaning of MARPOL Annex II products. For tank cleaning of Annex I products, relevant industry guidelines including the International Safety Guide for Oil Tankers and Terminals (ISGOTT) should be consulted.

8.1

Introduction

8.2

Procedures and Arrangements Manual

8.3 8.3.1 8.3.2 8.3.3 8.3.4

Supervision and Preparation Responsibility Tank cleaning plan Pre-cleaning meeting Preparations

8.4 8.4.1 8.4.2 8.4.3

Cargo Tank Washing and Cleaning General Tank washing atmospheres Prevention of toxic exposure during tank cleaning Prevention of static generation during tank cleaning Tank washing in an inert atmosphere Tank washing in a non-inert atmosphere Precautions for sounding tanks Transfer of wash water to slop tanks

8.4.4 8.4.5 8.4.6 8.4.7 8.4.8 8.5 8.5.1 8.5.2 8.5.3 8.5.4 8.5.5 8.5.6 8.5.7

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Special Cleaning Methods Introduction Reactive cargoes Manual cleaning Use of tank cleaning additives Steaming Recirculation washing Cleaning or gas freeing of cargo from non-cargo spaces

TANKER SAFETY GUIDE (CHEMICALS)

8.6 8.6.1

Mon itoring Tank Cleaning Operations Precautions for sounding tanks when not using a sounding pipe

8.7 8.7.1 8.7.2 8.7.3

Arrangements for the Disposal of Tank Wash ings and Slops General Management of slops Mandatory prewash water

8.8

Tank Cleaning in Port

8.9

Tank Cleaning Equipment

8.10 8.10.1

Gas Freeing Safe procedures for gas freeing after tank cleaning and cleaning by ventilation Opening up of cargo lines and handling equipment

8.10.2

8.1

INTRODUCTION Tank cleani ng and gas freeing are amongst the most dangerous operations that are carried out on board a chemical tanker. Although the safety record of chemical tankers worldwide is impressive, deviations from safe procedures have been the root cause of serious i ncidents and fatalities that have occurred in the past. In particular, during tank cleaning there is an increased risk from exposure to the many different chemical products involved, and from the physical dangers associated w ith the operation. In order to ensure crew safety when personnel are involved in tank cleaning arnd gas freei ng operations, it is important that all crew members understand the potential risks involved. It is the company's responsibility to provide safe procedures and the Master's responsibility to ensure compliance. The Master should ensure that the operation is supervised by a designated officer and that all personnel i nvolved follow th e correct procedures. The tank cleaning process sh ould ensure, whenever possible, that cargo, vapours or i nert gas are not released onto the deck area. It is th erefore of utmost importance that every possible care is exercised during all operations connected with tank cleani ng and gas freeing, and that the operations are carried out using the approved procedures and arrangements for th e ship. Tanks on a chemical tanker are required to be cleaned to a high standard. This may involve the crew having to enter tanks in order to finalise their preparation for the next cargo. In all cases where crew are required to enter tanks th e enclosed space entry procedure should be followed as described in Chapter 9. Whenever tank cleaning advice is received from a third party, the Master and/or the company sh ould ensure that the proposal complies with company procedures. If there is deviation from these procedures the advice should be rejected or be treated as a non-routine operation (see Section 3.8.2).

8.2

PROCEDURES AND ARRANGEMENTS MANUAL All ships certified to carry noxious liquid substances in bulk must be provided with a Procedures and Arrangements (P&A) Manual, approved by the flag administration, which addresses th e marine environmental aspects of removal and disposal of residues from cargo tanks, and describes how to perform these operations. The P&A Manual should be adhered to in all resp.ects, including the performance of mandatory prewash requirements in accordance with MARPOL Annex II (see also Chapter 4 of this Guide).

8.3

SUPERVISION AND PREPARATION

8.3.1

RESPONSIBILITY The Master should ensure that all tank cleaning and gas freei ng operations are appropriately planned, supervised and communicated to all i nvolved.

8.3.2 TANK CLEANING PLAN A written tank cleaning plan must be prepared and made available, for reference, to all personnel participati ng in th e operation. Any significant deviation from the plan must be approved in writi ng by the Master or by the designated officer. The written plan must be followed at all times and should cover: The type of cargo to be cleaned from each tank, and its characteristics. MSDS should be available so that personnel i nvolved are familiar w ith the hazards; The major risks duri ng cleani ng including toxicity, flammability, corrosiveness, reactivity, and temperature as well as the safety precautions to be taken;

169

The safety equipment and Personal Protective Equipment (PPE) to be available and ready for use throughout the operation and during connecting and disconnecting of hoses at the cargo manifold; The tanks to be cleaned, cleaning method, cleaning sequence and gas freeing arrangements; Monitoring the pumping of tank washings to ensure correct discharge/transfer; MARPOL requirements for the disposal of cargo residues and cleaning water (slops); Segregation of slops should be segregated to avoid mixing different categories of product; and Necessary actions required to keep the cargo deck area free from cargo vapours during tank washing and gas freeing operations.

8.3.3

PRE-CLEANING MEETING Before starting tank cleaning operations, the designated officer should lead a review of the tank cleaning plan with all crew members involved, especially those who will supervise operations. Crew members should be actively encouraged to contribute to the review of the plan, especially with regard to their role and any safety concerns which they may have. It should be recorded that the meeting has taken place.

8.3.4

PREPARATIONS Before commenci ng tank cleani ng or gas freei ng operations, the designated officer should confirm that all the necessary equipment is available and in working condition.

It should be made clear to all on board, i ncluding visitors, that tank cleaning and/or gas freei ng is taking place and that only those personnel directly i nvolved in the operation should be allowed within the cargo tank area. Tank cleaning or gas freeing alongside should not take place without the express permission of the terminal and port authorities. If allowed, all appropriate safety measures should be in place and shore personnel notified before commencing operations. Checks, i ncluding the following, should be made before operations commence: Followi ng the pre-cleani ng meeting (see Section 8.3.3), the amended written tank cleani ng plan should be made available to all involved; That appropriate PPE is used (see Section 3.11 and Appendix 10); That decontamination showers and eye-wash arrangements are ready for use; That no other operation is being carried out which could interfere with or affect the safety of the tank cleaning operation; That tanks and lines bei ng cleaned are segregated or sufficiently isolated from tanks that are clean or that contain cargo; That safeguards are in place to avoid contamination through shared vent and vapour return lines; That arrangements for cleaning vapour return lines are included in the tank cleaning plan; That all cargo tank openings not in use are kept closed; That discharge of slops is in compliance with MARPOL and with local requirements; and That fire-fighting equipment is ready for immediate u se.

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8.4

CARGO TANK WASHING AND CLEANING

8.4.1

GENERAL Water is the most common washing medium for cleaning cargo tanks. Its effectiveness can be improved by heating and/or by the addition of cleaning agents, if required. When cleaning a water reactive cargo, additional precautions should be taken. In particular circumstances, tanks can be cleaned by ventilation alone. If tanks are to be cleaned by venting alone (see Section 8.10) the process must be in compliance with the ship specific P&A Manual and the requirements of the IBC Code, Chapter 8. If recycling of wash water is used, the contaminants in the wash water should be considered and a risk assessment carried out. Heating of recycled wash water may change the flammability hazard.

8.4.2 TANK WASHING ATMOSPHERES Tank atmospheres The following tank atmospheres may exist, either alone or in combination: Toxic; Flammable; Inert; Non-inert; and/or Undefined. Tank washing may be carried out in the above atmospheres provided that appropriate precautions are taken and procedures followed. Toxic atmospheres On completion of the discharge of a toxic cargo the tank atmosphere should always be assumed to be toxic. Risk of exposure to toxic vapours is increased during tank cleaning and gas freeing. Flammable atmospheres On completion of the discharge of a low flash point cargo the tank atmosphere should always be assumed to be flammable unless it has positively been confirmed to be inerted. For chemical tankers, the primary means of preventing an ignition of cargo vapours is to eliminate all sources of ignition by ensuring that: Safe tank cleaning and gas freeing procedures are implemented which conform to IMO regulations and industry best practice; Ship's equipment has been designed and maintained to prevent any possible sources of ignition. The above measures are designed to control the ignition side of the fire triangle. By additionally controlling the oxygen side of the fire triangle the use of inert gas, usually nitrogen, further reduces the risk of ignition. For information on the fire triangle - see Section 10.4.1 of this Guide. Inert atmospheres For the purpose of this Guide for an atmosphere to be considered inert the oxygen content should not exceed 8% by volume (see Section 5.13.2). Non-inert atmospheres The tank atmosphere is not inert.

Undefined atmospheres The atmosphere in the tank is not measured and therefore may be oxygen deficient, flammable, toxic or any combination of the above.

8.4.3 PREVENTION OF TOXIC EXPOSURE DURING TANK CLEANING Crew members should be protected from exposure to toxic vapours by ensuring: That where possible, tank cleaning is carried out under fully closed conditions; Gas freeing operations comply with the IBC Code; Appropriate PPE is provided and worn;

• Access to cargo areas is restricted; and Ship's ventilation is correctly set and precautions are taken to monitor and prevent exposure in machinery spaces.

8.4.4 PREVENTION OF STATIC GENERATION DURING TANK CLEANING It should be noted that many tanks are washed w ithout the use of inert gas because of the cargo and its vapours being non-flammable. For flammable cargoes, static electricity generated during tank cleaning operations may create a spark which could ignite a flammable atmosphere. Tank cleaning using water under pressure can generate a significant amount of static electricity. In addition the wash water is often heated and this creates water vapour in droplets which can store an electrostatic charge. Washing media other than water may produce greater amounts of static electricity and further precautions might be required (see also Section 8. 5.4): Heated wash water may be utilised, but use should be discontinued if the gas concentration reaches 35% of the LFL. A hot wash for a low flash point product should only take place following a full (i.e. top to bottom) cold wash cycle; The tank should be kept drained during washing. Washing should be stopped, as necessary, to clear any build up of wash water; Measures should be taken to guard against ignition from mechanical defect o1 machinery, e.g. intank (submerged) cargo pumps, tank washing machines, tank gauging equipment, etc; Precautions should be taken to eliminate the risk of mechanical sparks from metallic objects such as hand tools, sounding rods, sample buckets, etc. being dropped into the tank; Fixed tank cleaning machines should be securely bonded to the ship's structure to ensure that any static electricity generated will be safely drained away; and Portable tank cleaning machines should also be 'continually electrically bonded' through the tank cleaning hoses to the ship's structure. This will ensure that any charge is drained so that, when it is lifted from the tank, a spark will not be generated between the machine and the ship's structure as it passes through the tank cleaning hatch.

Static electricity generated during tank cleaning and gas freeing presents a serious risk of fire and explosion.

m

TANKER SAFETY GUIDE (CHEMiCAL5)

8.4.5 TANK WASHING IN AN INERT ATMOSPHERE Although the atmosphere in an inerted tank is non-flammable, the following precautions should be observed: Washing should be carried out under closed conditions utilising fixed tank cleaning machines; All openings to the tank should be kept closed; Positive pressure in the tank should be maintained; Before each tank is washed, the oxygen content in the tank should be measured at a point about one metre below the deck. The oxygen level should not exceed 8%; If during washing the oxygen level in the inert gas supply exceeds 5% by volume or the pressure

of the atmosphere in the tank is no longer positive, washing should be stopped until safe conditions are restored; The tank should be kept drained during washing. Washing should be stopped, as necessary, to clear any build up of wash water; and The oxygen content and pressure of the inert gas being delivered should be monitored. Washing with portable machines When using portable machines it is not possible to ensure that an over pressure of inert gas is maintained in the tank. Air may be drawn into the tank increasing the oxygen content. The tank atmosphere should be considered to be non-inert. Chemical tankers are designed to ensure that tank washing in a non-inerted atmosphere is as safe as is practicable. This is achieved by limiting cargo tank sizes, restricting the size and throughput of tank cleaning machines and compliance with regulations.

8.4.6 TANK WASHING IN A NON-INERT ATMOSPHERE When cleaning a tank that has contained a flammable product the only effective means of preventing an explosion is to eliminate all sources of ignition. In all cases after carrying a flammable cargo, the atmosphere in an empty, non-inert tank should be treated as flammable. The only way to ensure that an explosion cannot occur during washing in a non-inert atmosphere is to make certain that there can be no source of ignition.

Compliance with company procedures on tank cleaning operations is essential to ensure that tank cleaning carried out in a non-inerted atmosphere is safe.

Tanks stripped in compliance with P&A Manual If the tank has been stripped in compliance with the P&A Manual, tanks can be washed provided that the following precautions are taken: When portable washing machines are used, the tank cleaning machine and hoses should be connected to the tank cleaning line before being lowered into the tank. Connections should not be broken until after the machine has been removed from the tank; Ropes made of synthetic fibres should not be used to support the tank cleaning machines; Tank cleaning machines should have a throughput of less than 60m3 per hour, and nozzles should have a throughput of less than 17.Sm' per hour; The total water throughput per cargo tank should be kept as low as practicable and must in no case exceed 11 Orn' per hour; The tank should be kept drained during washing. Washing should be stopped to clear any build up of wash water;

173

Recirculated wash water should not be used. The presence of traces of cargo in the wash water may increase the generation of static electricity; Equipment lowered into the tank should be bonded to the ship's structure (se-e Section 5.11 .2); Steam should never be injected into a tank w ith an atmosphere that might be flammable; and l ow flash or static accumulator products should never be used as a cleaning medium.

Failure to follow rules, regulations, best practice guidelines and company procedures has been the cause of many chemical tanker fires and explosions, particularly during tank cleaning and gas freeing.

Tanks not stripped according to P&A Manual In exceptional circumstances the ship may not be able to strip tanks in compliance with the P&A Manual. Any subsequent actions should be considered to be a non-routine o;peration (see Section 3.8.2). After any prewash requirement, tank washing can be carried out following the procedures for washing in a non-inert atmosphere (see above).

8.4.7

PRECAUTIONS FOR SOUNDING TANKS If a sounding pipe is not used, it is essential that any metallic components of the s.ounding rod or other equipment are bonded and securely earthed until removed from the tank. This precaution should be observed at all times. The following measures should also be taken: An interface detector of metallic construction may be used if earthed to the ship by means of a clamp or bolted metal lug; A metal rod or non-metallic equipment may be used on the end of a metal tape which is earthed to the ship; A metal sounding rod suspended on a natural fibre rope should not be used even if the end at deck level is fastened to the ship, because the rope cannot be com pletely relied upon to act as an earthing path; and Synthetic fibre ropes or chains should not be used for lowering equipment into cargo tanks.

8.4.8 TRANSFER OF WASH WATER TO SLOP TANKS Washing water or slops should be transferred to the receiving tank through the ship's fixed pipeline system (see Section 8. 7).

8.5

SPECIAL CLEANING METHODS

8.5.1

INTRODUCTION Water washing may be inadequate or inappropriate after the carriage of certain products because tanks can only be cleaned effectively utilising special cleaning methods or the use of particular cleaning agents. When alternative cleaning mediums or methods are planned, use of these should comply with company procedures. Special methods involving cleaning agents create additional hazards for the crew. Where a written procedure does not exist this should be considered a nonroutine operation (see Section 3.8.2). Where a special cleaning method is to be used in port, local authorities may impose additional safety or environmental requirements.

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TANKER SAFETY GUIDE (CHEMICALS)

8.5.2

REACTIVE CARGOES Some cargoes may react with certain cleaning agents and produce toxic or flammable vapours, and may polymerise or render equipment such as pumps inoperable. The tank cleani ng plan should identify and mitigate potential reactions between the cargo and cleaning agent(s). Alternative washing mediums might have to be used when cleaning from a cargo that is water reactive. When selecting an alternative washing medium the following should be considered: Whether it is suitable for the cargo being cleaned; Whether the vessel is certified to carry the washing medium; Whether it is suitable for use with the available ship's equipmen t; and Whether the residues can be safely stored and disposed of i n accordance w ith MARPOL and local requi rements.

8.5.3

MANUAL CLEANING In exceptional ci rcumstances it may be n ecessary for personnel to enter a tank in order to clean residues from the tank by manual cleaning. For particularly difficult residues a chemical solvent o r other cleaning agent may be required. This process may create additional risks such as increasing the toxicity or flammability of the tank atmosphere. The amount of chemical solvent or other agent used sh ould therefore be the minimum required. The operation should only proceed once all control measures are i n place to en sure the safety and health of the crew involved. Prior to commencing any manual cleaning operation the following should be complied with: The task must be analysed to establish that there are no alternative cleanin g methods; Enclosed space entry procedures should be followed (see Section 9 .4); The MSDS for the cleaning agent or chemical solvent used should be available o n board and sh ould be consulted; A risk assessment should be carried out; Appropriate PPE should be worn; The personnel involved sh ould be experienced i n the particular operation; The crew members enteri ng the tank should be fully briefed, especially regarding the action to take i n an emergency; and The cleaning equipment to be used should be checked and confirmed to be i n good w orking order. Spraying with toxic or flammable chemicals or solvents sh ould never be considered as a rout ine operation (see Sections 3.8.1 and 3.8 .2 of this Guide).

lives can be lost on chemical tankers due to poorly prepared and executed manual tank cleaning operations.

175

8.5.4

USE OF TANK CLEANING ADDITIVES Tank cleaning additives used on a chemical tanker may be toxic and/or corrosive. When heated they may emit dangerous fumes. Personnel handling cleaning additives should wear PPE as recommended by the manufacturers. When a washing medium other than water is used to wash a tank, such as mi neral oil or chlorinated solvent, its discharge is controlled under the same provisions of MARPOL Annex I or Annex II applicable to the medium had it been carried as cargo. Tank washing procedures i nvolving the use of such a medium must be set out in the P&A Manual and be approved by the flag administration. Tank cleaning additives used on board have to be approved by IMO and an MSDS must be provided. Annex 10 of the latest MEPC.2/Ci rc contains a list of approved cleaning additives (see also Chapter 4 of this Guide). Cleaning additives that are not cargo should be carried and stored according to tile requi rements of the International Maritime Dangerous Goods (IMDG) Code.

8.5.5

STEAMING Steam should never be introduced into a tank with an atmosphere which may be flammable.

The standard method for removing chlorides by steaming uses deionised (DI) water. If steami ng is required the tank must be gas free.

8.5.6

RECIRCULATION WASHING In some ci rcumstances recirculati ng a washing medium may be the most effective method of cleaning a tank. The following guidelines apply in a non-inerted cargo tank: The washi ng medium should be non-flammable; Under no circumstances should a static generating product be used; and Recirculation should be carried out under fully closed conditions. Should it be necessary to recirculate a flammable product, this process is considered to be a nonroutine operation (see Section 3.8.2). The operation should be subject to a full risk assessment and the approval of the vessel 's operator obtained. As a mini mum the following safety precautions should be observed: The cargo tank must be inert and a positive pressure maintained; Recirculation should only be carried out under fully closed conditions; and The atmosphere in the tank should be measured frequently.

8.5.7

CLEANING OR GAS FREEING OF CARGO FROM NON-CARGO SPACES It may be necessary to clean non-cargo spaces into which cargo or vapours have leaked. This should be treated as a non-routi ne operation that should be subject to a full risk assessment and the approval of the vessel's operator should be obtained (see Section 3.8.2).

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TANKER SAFETY GUIDE (CHEM,CALS)

8.6

MONITORING TANK CLEANING OPERATIONS

8.6.1

PRECAUTIONS FOR SOUNDING TANKS WHEN NOT USING A SOUNDING PIPE If gauging is required duri ng tank cleani ng the ideal system is a tank radar system. If manual gauging is required, only hermetically sealed and bonded gauges should be used. To avoid risk of damage to the gauge, washing will need to be suspended. Some vessels are equipped with sounding pipes which extend from the deck to the bottom of the tank. These allow the tank contents to be measured without the need to stop the washing operation.

8.7

ARRANGEMENTS FOR THE DISPOSAL OF TANK WASHINGS AND SLOPS

8.Z1

GENERAL Final disposal of slops or wash water should be in accordance with the ship's P&A Manual and MARPOL requirements. Tank washings and slops may be retained on board in a slop tank for later disposal at sea if permitted, or ashore to an approved shore reception facility (see Section 4.3.2).

8.Z2

MANAGEMENT OF SLOPS The compatibility of various cargo and cleaning chemicals should be checked prior to being transferred to a common slop tank. The following should be avoided: Mixing of slops from Annex I (oil) cargoes with slops from Annex II (chemical) cargoes; and Mixing of slops from incompatible cargoes. If the ship's cargo tanks are used as slop tanks, care should be taken to avoid introducing slops from cargoes which are incompatible with the tank coating. Some cargoes which are compatible w ith the coating may, when mixed with water or other cargoes, form acids and thus damage the coating. Should slops be required to be retained on board for more than a few days then the contents of the slop tank w ill need to be monitored for any signs of a chemical reaction or for the build up of flammable vapours.

Care should be taken to avoid incompatible cargoes being mixed in slop tanks. drain tanks. vent lines and manifold drip trays.

8.Z3

MANDATORY PREWASH WATER MARPOL requires that, following cargo discharge and the mandatory prewash, residues of Category X substances (see Section 4.3.2) are to be unloaded to a shore facility prior to the ship leaving the port of discharge. If the discharge of a Category Y or Z substance is not carried out in accordance with the P&A Manual, or if it is a high viscosity or solidifying substance (see Section 6.3.5) in Category Y, MARPOL requires that a prewash is carried out before the ship leaves the port of discharge. The resulting tank washings of the prewash must be unloaded to a suitable reception facility at the port of discharge or another port with a suitable reception facility, provided that confirmation in writing is received that a reception facility at that port is available, that it is adequate for such a purpose and that the administration of the port state has approved the operation.

177

8.8

TANK CLEANING IN PORT If tank cleaning is required to be carried out in port the following precautions should be obseived: Permission should be obtained from the terminal operator and, where necessary, from the port authority; The release of cargo vapours from the cleaning or gas freeing operations should be closely monitored and the operation stopped if agreed safe gas concentration limits are exceeded; and Precautions should be taken to ensure that the release of cargo vapours does not affect craft alongside and others in the vicinity.

8.9

TANK CLEANING EQUIPMENT Before any operations begin, the designated officer should confirm that adequate checks have been made to establish that all equipment to be used during tank cleaning operations is in good working order. Tank cleaning equipment should only be used for its intended purpose and should not be used for any other purposes. For a description of tank cleaning and gas freeing equipment see Sections 5.11 and 5.12 of this Guide.

8.10 GAS FREEING 8.10.1 SAFE PROCEDURES FOR GAS FREEING AFTER TANK CLEANING AND CLEANING BY VENTILATION The IBC Code, as well as the ship's P&A Manual, include requirements for equipment and procedures to be followed to ensure that tanks are gas freed safely. Gas freeing operations need to be carefully planned, taking into account the vapours to be expected which may be flammable, or toxic or corrosive. The following guidelines should be followed: Cargo line valves other than those required for ventilation should be closed and secured; Venting of toxic and flammable gas during gas freeing should be through the vessel's approved gas freeing outlets, which may utilise high velocity vent valves sufficient to carry the vapours clear of the deck; Only when the flammable vapour concentration at the outlets has been reduced to 30% of the l ower Flammable limit (LFL) and, in the case of a toxic product, the vapour concentration (TLV) does not present a significant health hazard, should gas freeing be continued at cargo tank deck level;

If portable ventilation equipment is to be used, all other tank openings should be kept closed until compliance with the above requirements can be met; Portable fans powered by electricity should not be used; Appropriate portable fans should be positioned to ensure that all parts of the tank being ventilated are equally and effectively gas freed. Fans should generally be sited at the opposite end of the tank from the ventilation outlets and have sufficient power to penetrate to the bottom of the space; An effective electrical bond should exist between the portable fans and the ship; There is a risk when fixed equipment is used for gas freeing a tank, while being used to ventilate another tank in which washing is taking place, that cross contamination could occur. In order to avoid this risk, such equipment should not be used for gas freeing a tank while simultaneously being used to ventilate another tank that is being washed;

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TANKER SAFETY GUIDE (CHEMICALS)

Where cargo tanks are gas freed by permanently installed fans through the cargo lines, the line system should be drained before venting; The wind direction should be monitored to ensure cargo vapours do not enter air intakes to the accommodation or machinery spaces; Consideration should be given to switching the ship's ventilation systems to recirculation mode. If at any time it is suspected that cargo vapours are being drawn into the accommodation or machinery spaces the gas freeing operation should be immediately stopped; and After gas freeing a tank, all ventilation should be stopped to allow the atmosphere within the tank to stabilise. Gas measurements should then be taken to verify that the atmosphere is free of flammable and/or toxic vapours. Even when a tank has been initially confirmed as gas free, cargo vapours trapped within valves, pipelines and the coating may leak out and the atmosphere may become dangerous for entry. The atmosphere of any tank to be entered should be tested, and further gas freeing carried out if the atmosphere is found to be unsafe. Enclosed space entry procedures should always be followed, see Chapter 9 of this Guide.

8.10.2 OPENING UP OF CARGO LINES AND HANDLING EQUIPMENT Cargo pipelines, manifold crossovers and vent lines should be cleared of cargo residues, and should be cleaned and gas freed at the same time as the cleaning and gas freeing of the cargo tank. Residues of cargo may be trapped in any section of a cargo pump, cargo pipeline, vent line or heating coil, therefore proper PPE should be worn (see Section 3.11 ). If located in an enclosed space, proper enclosed space entry procedures should be followed (see Chapter 9). If it becomes necessary to open up cargo lines or cargo handling equipment in a cargo tank or in a cargo pumproom, the following precautions should be taken in addition to the enclosed space entry procedures advised in Chapter 9: The task should be subject to a risk assessment being carried out and, provided that adequate safeguards can be implemented, a permit issued by a responsible officer; After gas freeing the space, the equipment and associated pipeline should be isolated as far as possible, and further ventilated if required; The atmosphere in the space should be tested to ensure that it is free of flammable and toxic vapours and regularly monitored; and Fire-fighting equipment should be ready for immediate use.

179

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CHAPTER 9

ENTRY INTO ENCLOSED SPACES

9

ENTRY INTO ENCLOSED SPACES

This chapter gives guidance on the procedures to follow when planning entry into an enclosed space. Unlike oil tanker operations, entry of personnel into cargo tanks is a more common practice during cargo operations

on board chemical carriers, and an operator's procedures should make special allowance for the particular risks involved. Jn addition to the particular risks associated with the atmosphere in an enclosed space, the same risks exist as in any working environment and include 'slips, trips and falls'. The characteristics of enclosed spaces, however, make the preparation and planning of procedures to address such accidents additionally difficult. Some of the guidance in this chapter duplicates advice contained elsewhere in this Guide, and covers this single issue in considerable detail. However, the issue is sufficiently important to justify this approach.

9.1

Introduction

9.7

Work in Enclosed Spaces

9.2

Hazards Oxygen deficiency Toxic and/or flammable gases Presence of inert gas including nitrogen Oxygen enrichment

9.8

9.2.1 9.2.2 9.2.3 9.2.4

Entry into an Enclosed Space where the Atmosphere is Known or Suspected to be Unsafe

9.9

9.3

Atmosphere in Enclosed Spaces

9.4

9.4.1 9.4.2

Requirements for Enclosed Space Entry Planning Entry permit

9.9.1 9.9.2 9.9.3 9.9.4 9.9.5

Rescue from Cargo Tanks and Other Enclosed Spaces General Preventing enclosed space accidents Rescue and recovery organisation The rescue operation Rescue and recovery equipment

9.5

Testing Before Entry

9.6

Enclosed Space Entry Entry into enclosed spaces other than cargo tanks

9.6.1

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9.1

INTRODUCTION An enclosed space is a space with poor or no natural ventilation which is not designed for continuous occupancy, where access is limited and which may contain a dangerous atmosphere. Breathing pure nitrogen will inhibit the reflex to breathe and can rapidly lead to asphyxia and death. Enclosed spaces include but are not limited to cargo tanks, double bottoms, cargo pumprooms, duct keels, 18 ballast tanks, void spaces, peak tanks, cofferdams, chain lockers, bunker tanks, freshwater tanks, machinery internals and any other spaces that are normally kept closed. An enclosed space may include a deck area that due to its construction and location has poor or limited access and where a dangerous atmosphere may accumulate. The hazards identified below may be present around such a deck area (see Section 2.7. 1). IMO Guidelines Due to the high risks associated with enclosed space entry and the number of accidents that have occurred on board various types of ship, IMO has issued two specific sets of safety Guidelines: 1.

Assembly Resolution A.1050(27) (Revised Recommendations for Entering Enclosed Spaces Aboard Ships);

2. MSC.1/Circ.1401 (Guidelines on Tank Entry for Tankers Using Nitrogen as an lnerting Medium). The above !MO Assembly Resolution and Guidelines are important documents that should be followed when entering enclosed spaces and when inert gas (nitrogen) is used as an inerting medium. The guidance in this chapter provides for practical application of these IMO guidelines.

9.2

HAZARDS Enclosed space atmospheres can be hazardous due to one or a combination of the following conditions: Oxygen deficiency; Inert gas including nitrogen; Presence of toxic and/or flammable gases; Accumulation of toxic and or heavy gases at lower levels within the space; and/or Oxygen enrichment. When it is intended that personnel should enter or work in an enclosed space, care should be taken to create and maintain safe working conditions. It should be recognised that conditions within an enclosed space may change while personnel are in the space. The use and monitoring of personal multi-gas detectors is therefore important and will help to identify any change of conditions.

The following contributory factors have been frequently identified following enclosed space accident investigations: •

Non-compliance with procedures;

•

Poor supervision;

•

Complacency and over familiarity leading to short cuts being taken;

•

Monitoring equipment not used or not working properly; and

•

Improper action in an emergency.

18 On some ships, there is no door or hatch restricting passage from a pumproom into a duct l:eel. Even in these circumstances, the duct keel should be regarded as being a separate enclosed space.

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In addition to the particular risks associated with the atmosphere in an enclosed space, the same risks exist as in any working environment i ncluding 'slips, trips and falls'. A number of accidents have involved falls from h eight i nside enclosed spaces. It is particularly important that rescue and recovery access to all appropriate parts of the enclosed space is considered, as well as the entry and exit of rescuers and their equipment. The presence of toxic gases from cargo residues should always be expected in cargo tanks and adjacent spaces. Each gas presents its own dangers and personnel should be aware of the properties of the gases involved and the safe levels of exposure permitted. The impulse to go to the rescue of personnel who have collapsed in an enclosed space presents a particular risk. It is a common human reaction to go to the aid of a colleague i n difficulties. However, far too many additional deaths have occurred from impulsive or ill prepared rescue attempts. It is essential that all personnel are aware of the dangers of attempting to rescue colleagues without assistance.

Figure 9.1 - Cargo Tank Internal Structures In an emergency, the first action should be to activate the emergency alarm and wait for assistance (see Section 9.9). The nominal oxygen level in fresh air is 21 % by volume. Any space having an atmosphere of less than this should not be entered until the reason for the low oxygen level has been established and appropriate measures taken. When the oxygen supply to the brain is depleted, victims will frequently feel dizzy, become disorientated, and may develop a headache before finally losing consciousness. By the time the victim is aware of these symptoms they may not be able to act rationally and may not be able to leave the space safely. There is a danger of permanent brain damage after only 4 minutes in an oxygen deficient atmosphere. A successful rescue therefore depends upon the victim being resuscitated in the shortest possible ti me. At oxygen concentrations: Below 21 % to 16% - pulse and breathing rates drop, and mental functions are impaired; Below 14% - severe symptoms are experienced, including increasing fatigue, emotional upset, poor judgment, and faulty coordination. Further reductions result i n nausea, vomiting, permanent heart damage and loss of consciousness; and Below about 5% - a coma may occur within 40 seconds, requiri ng emergency administration of oxygen to have any chance of survival.

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9.2.1

OXYGEN DEFICIENCY When an enclosed space is left closed and unventilated for any length of time, the i nternal atmosphere may become oxygen deficient due to the natural process of oxidisation of steel (rusting). The oxidisi ng process depletes the oxygen within the space. The use of inert gas or nitrogen w ill also reduce the oxygen content of the tank. Cargoes, such as vegetable o r animal oils, that are prone to decomposition, fermentation or slow oxidisation may deplete the oxygen content in the tank. These processes may also generate toxic gases (hydrogen sulphide and carbon monoxide) which present an added risk, especially in tanks which have been emptied but not yet adequately cleaned.

9.2.2 TOXIC AND/ OR FLAMMABLE GASES In spaces that have previously contained toxic and/or flammable cargoes th ere is a danger to personnel even if the space has been cleaned, tested and previously found to be safe for entry. Some toxic and/or flammable cargoes may be absorbed by tank linings (especially epoxy type coatings) and, as these leach out, the space may become unsafe for entry. Cargo residues may be trapped within tank fittings such as heating coils, cargo pumps and vapour lines, and these may be released i nto the tank after initial cleani ng has been completed.

9.2.3

PRESENCE OF INERT GAS INCLUDING NITROGEN Nitrogen is a commonly used inert gas on chemical carriers. Whereas inert gas produced by combustion, in an inert gas generator, is usually detectable by smell, it is very important to be aware that nitrogen is odourless and colourless and therefore presents particular risks. Nitrogen is also used for cargo quality control purposes.

Dangers o f nitrogen - see also Chapter 7 Nitrogen is a colourless and odourless gas that will cause oxygen deficiency i n confined spaces, and at exhaust openi ngs on deck, during the purgi ng of tanks and void spaces. The normal air we breathe contains about 78% nitrogen and 21 % oxygen with much of the remainder made up of a small amount of carbon dioxide. Breathing is stimulated and regulated by the amount of carbon dioxide present in the blood. In a space where the oxygen has been partly replaced by carbon dioxide, due to corrosion/rusting, decomposition of organic material, or inert gas produced by com bustion, the i ncrease in carbon dioxide stimulates the lungs to work harder and thus sends a clear message that should alert the person to the danger. However, the effect of nitrogen gas is to reduce the oxygen content but also with an associated drop i n carbon dioxide levels in the blood. As a result the lungs are not stimulated to work harder to compensate for the lack of oxygen. The person is not aware of any danger and may even feel a state of euphoria before the stimulus to breathe is removed completely and the person is asphyxiated.

9.2.4 OXYGEN ENRICHMENT Oxygen behaves differently to air, compressed air, or inert gas such as nitrogen. It is very reactive. Pure oxygen, at high pressure, such as from a cylinder, can react violently with common materials such as oil and grease. Other materials may catch fire spontaneously. Nearly all materials including textiles, rubber and even metals w ill burn vigorously in oxygen. Even a small i ncrease in the oxygen level in the air to 24% can create a dangerous atmosphere. It becomes easier to start a fire, which will then burn hotter and more fiercely than in normal air. It may be almost impossible to put the fire out. A leaking valve or hose in a poorly ventilated room or confined space can quickly increase the oxygen concentration to a dangerous level.

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The main causes of fires and explosions when using oxygen are: Oxygen enrichment from leaking equipment; Use of materials not compatible with oxygen; Use of oxygen in equipment not designed for oxygen service; and Incorrect or careless operation of oxygen equipment.

9.3

ATMOSPHERE IN ENCLOSED SPACES Enclosed spaces, including tank atmospheres may be contaminated by leaks from adjacent tanks or by the improper operation or failure of cargo, vapour and inert gas lines and valves. Enclosed spaces should not be entered until it is confirmed that the atmosphere is safe and then only for a specific authorised purpose.

Entry precautions It is vital that no personnel enter an enclosed space until it is confirmed that the atmosphere is safe. Suitable notices should be prominently displayed to warn and inform personnel about the dangers of entering enclosed spaces. Instructions should clearly explain the precautions to be taken when entering tanks or other enclosed spaces, and listing any restrictions placed upon the permitted work. Entry doors or hatches leading to enclosed spaces should at all times be secured against entry, when entry is not required. The company should ensure that their enclosed space entry procedures are understood and followed .

9.4

REQUIREMENTS FOR ENCLOSED SPACE ENTRY The tank cleaning plan should not permit personnel to enter a tank unless it is confirmed safe for entry.

0

--

NOTSAfE FOR ENTRY

ENTRYTAG

'""'- -

Figure 9.2 - Tank Entry Prohibited

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0

9.4.1

PLANNING Prior to entering an enclosed space, all personnel who are to be involved i n the work should meet to: Define the purpose of entering the space; Identify the steps required to achieve the purpose; Identify the risks i nvolved (see Section 3.7); Develop a plan of action; and Agree responsibilities. The meeti ng should address: Manpower requirements for the enclosed space entry: Under the Master's authority, an officer should be designated with responsibility for the work and for compliance with related procedures; Atmosphere testing should be by personnel trained in the use of the equipment used. Manufacturers' procedures should be followed and equipment should be correctly calibrated; and An attendant should be designated who should remain outside the entrance to the enclosed space. Their primary function is to maintain a safety watch over the work and personnel involved and to maintain communications. The attendant should be trained in emergency response and should be responsible for initiating emergency procedures in the event of an incident; Identification and mitigation of physical hazards; Identification of safety, fire-fighting, communication, escape and rescue and other equipment and tools required; Information to personnel entering enclosed spaces on the particular hazards of the operation; How to maintai n safe operating conditions in the enclosed space; and A review of emergency procedures, including that: The rescue party leader should coordinate operation from close to the enclosed space access but should NOT enter the space; Sufficient personnel should be available to recover a casualty from the enclosed space; The rescue team should have sufficient personnel, all trained in the use of rescue equipment and first aid; and A decision to recover a casualty from the enclosed space should assess the nature of injury and need for immediate first aid against the risk associated with remaining longer in the space.

9.4.2 ENTRY PERMIT Prior to allowing personnel to enter an enclosed space, an entry permit should be issued. An example of an Enclosed Space Entry Permit is provided i n Appendix 7. It is recommended that the permit should be signed by the Master or a designated officer with sufficient knowledge and experience of the procedures requi ring compliance. The entry permit should contain a clear indication as to its maxi mum period of validity, which should not exceed 8 hours. It should also describe the maximum permitted time between testi ng of the atmosphere and entry of personnel i nto the space. A single permit for entry into more than one enclosed space may be issued as defined in the company's SMS. However, this should only be applicable for entry to cargo tanks (see Sections 9.6 and 9.6.1 ).

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It is essential to ensure that while personnel are withi n an enclosed space the levels of oxygen and any contaminants are regularly checked, and that personnel entering a space use multi-gas detectors, and that the levels remain withi n safe limits. If there is any doubt regarding the oxygen level or the presence of toxic or flammable gases the space should be immediately evacuated. A condition of the entry permit should require that if the enclosed space is vacated for any reason, such as for refreshment or a meal break, ventilation should be continued during the break and the atmosph ere of the enclosed space should be fully retested prior to re-entry. Entry permits must only remain valid for as long as the permit conditions are met. The responsible officer supervising enclosed space entry should confirm that:

If enclosed space entry is in the cargo area, no inerting or purgi ng is taki ng place;

The space has been thoroughly ventilated by natural or mechanical means to remove any toxic, hazardous or flammable gases, and to ensure that there is an adequate level of oxygen throughout the space; Adequate illumination is provided; All personnel entering the space are properly trained in enclosed space entry procedures, and are familiar with th e company's safety and emergency procedures; There is a system in use to record personnel entering and leaving the space; The atmosphere of the space has been tested and found safe before any personnel enter the space (see Section 9.5); All personnel entering the space are weari ng appropriate PPE and should be provided with calibrated personal multi-gas detectors to monitor the levels of oxygen, LEL, carbon monoxide and other gases as appropriate; All crew mem bers entering th e space understand that the space is to be vacated immediately if any personal multi-gas detector alarm is activated; A crew mem ber (attendant) who is familiar with the action to take in the event of an emergency is standing by at the entrance and is in direct contact with persons within the space and with the navigating bridge or control room as appropriate; A reliable system of communication has been established, tested and is understood, both by those entering the space, and by the crew member (attendant) standing by at the entrance; The duty officer(s) on the bridge or i n the cargo control room and in the engi ne room are aware of the enclosed space entry operations; Rescu e procedures are understood and sufficient trained personnel are readily available to form a rescue party; Rescu e equipment, suitable for the en closed space, is ready for immediate use. Rescue equipment should be readily capable of being placed i nto and recovered from the space and moved to any part of the space in which personnel may work; Outside contractors involved i n enclosed space operations comply with the company's enclosed space entry procedures. It should be confirmed that any such contractors are aware of the particular dangers involved and the actions to take i n an emergency (see Section 3.6); and PPE used by outside contractors, as a minimum, complies with the ship's equipmen t standards and procedures for use. Irrespective of whether ship's crew or outside contractors are entering an enclosed space the person standing by at the entrance (attendant) should always be a member of the ship's crew.

No tank entry should be made when any inerting operations are being carried out in the cargo area.

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Figure 9.3 - Tank Entry Permitted

A system should be in place to indicate which cargo tanks are safe for entry by marking (or tagging) all appropriate tank entry hatches.

9.5

TESTING BEFORE ENTRY Before the space is entered it should be thoroughly ventilated. The time necessary to ensure thorough ventilation depends upon the size and construction of the space, the capacity and efficiency of the ventilation system, th e level of contamination and the density of the vapour to be displaced. Effective ventilation capacity is also depen dent upon the size and position of openings to the space. Well placed openings improve the flow of air and will help ensure that all areas within the space are effectively ventilated. Once the space has been ventilated, the atmosphere should be ch ecked using a suitable instrument(s) to test for oxygen, flammable gases or vapours, carbon monoxide, hydrogen sulphide and other toxic gases as appropriate: The oxygen content should be measured and a nominal reading of 21 % achieved. Any space with an atmosphere having less than 21% oxygen by volume should NOT be entered until the reason for the low oxygen level has been established and resolved; Flammable vapours should be measured with a suitably sensitive combustible gas detector. The concentration of flammable vapour must be below 1% of the Lower Flammable Limit (Lfl) before entry can proceed; and A toxic gas detector should be used to ensure that the levels of toxic gases are within the required safe Threshold limit Value (TLV). 19

Multi-gas detectors intended to be carried by personnel within an enclosed space are not suitable for conducting pre-entry atmosphere testing.

19 OEL and MAK are other ei
to»:: chemicals.

189

Ventilation should be stopped about 10 mi nutes before the above tests are carried out and not restarted until after the tests have been completed. A number of test readings should be taken from different locations and levels within the enclosed space, utilising ext ension hoses as appropriate. Gas or vapour with a relative density greater than that of air will be found at the bottom of any space, and those that have a relative density less than that of air w ill be found at the top of a space. Gas and vapour will also tend to remain where the ventilating airflow is least effective. Testing and measurement should only be carried out by personnel trained and proficient i n the use of the equipment. Testi ng equipment should comply with an appropriate recognised standard and be properly maintained and calibrated. Testing equipment should only be used to measure gases for which it is designed and withi n the limits set by the manufacturer.

Even after a space has been made gas free and found to contain a safe atmosphere, local concentrations of gas should always be suspected. Cargo residues may be trapped w ithin tank coatings, fittings or in residual scale. Generation of vapour should always be considered possible, even after loose scale has been removed. As persons move around within an enclosed space they should always be aware of the dangers of isolated concentrations of gas and carry out further tests. This is especially important in spaces with a com plicated internal structure where effective ventilation is difficult to achieve. Testing of enclosed spaces from outside the space should be continued at appropriate intervals while personnel work withi n the space.

If any of the criteria required above for i nitial entry to the space are not mai ntained the space should immediately be evacuated.

9.6

ENCLOSED SPACE ENTRY On chemical carriers entry i nto cargo tanks is a more frequent requirement than it is on oil tankers. Chemical carrier operators' instructions should make allowance for this when prepari ng cargo tank entry procedures. It is essential that procedures ensure the safety of personnel but are not so onerous that personnel become incli ned to disregard them . A system should be in place to indicate which cargo tanks are safe for entry by marking (or tagging) all appropriate tank entry hatches. The marking should be unambiguous, and procedures should be such that the absence of a safe to enter mark will prohibit entry. The tank to be entered should be segregated from all other spaces which contai n or may contai n a non-gas free atmosphere. All common line valves should be lashed in the closed position and labelled. All cargo pipes in the tank being entered should have been flush ed and drai ned. Entry permits may be coordinated so that more than one cargo tank is shown on one entry permit. This helps to simplify the administration of permits, and avoids possible duplication and confusion as to which permit applies to which tank. If such a combined permit system is used there should be rigorous control measures i n place to ensure, if one or more tanks named on the permit are subsequently tested and found to be unsafe to enter, that the whole permit is cancelled. A new permit w ill then need to be issued for all tanks.

It is particularly important that the permit system is supplemented by the marki ng of tank lids with notices indicating which tanks are safe to enter.

Any tank to be entered must be completely disconnected from any active cargo operations.

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9.6.1

ENTRY INTO ENCLOSED SPACES OTHER THAN CARGO TANKS On chemical carriers, entry into enclosed spaces other than cargo tanks should be treated with the same degree of caution as for cargo tanks. Familiarity with routine work in cargo tanks should not be allowed to induce any sense of over confidence or complacency when entering oth er types of enclosed space. For tanks other than cargo tanks it is recommended that a permit to enter is only issued for one space at a time and that multi-space permits are not used. Rescue equipment, suitable for the enclosed space, should be ready for immediate use. Dangers in such spaces include: Depletion of oxygen due to rusting; Presence of cargo and cargo vapours that may have leaked from adjacent tanks; and Inert gas or nitrogen getting i nto such spaces. The atmosphere should therefore be checked for both oxygen content and cargo vapour before entry.

9.7

WORK IN ENCLOSED SPACES Ventilation should be continuous while personnel are inside the space and the atmosphere should be monitored at appropriate intervals, including by the use of personal m ulti-gas detectors. If personnel begin to feel dizzy or unwell they should leave the space immediately. In particular, tests should be made before the resumption of work after a break and prior to re-entry. It is a normal practice i n some trades for personnel to be sent into a cargo tank being drained of animal and vegetable oils or fats in order to sweep the final traces towards the pump suction. Familiarity with this routine practice should not obscure the potential dangers of cargo generated vapours and the presence of an oxygen deficient atmosphere. Personal multi-gas detectors and appropriate PPE should be used. Adequate ligh ting and continuous ventilation should be maintained throughout the period that the space is occupied. Further dangers associated with cargo sweepi ng include: Heat exhaustion; Burns from heating coils; Slips, trips and falls due to slippery surfaces; and Burns caused by corrosive cargoes. Where shore workers are employed to carry out cargo sweeping, confirmation should be obtained that they are fit for such work and at least meet the requirements of th e company's SMS (see also Sections 3.5, 3.6 and 6.7.2 1). Even after a cargo tank has been cleaned there will always be a possibility of some cargo remaini ng, which could be a source of further flammable or toxic gas, including hydrogen sulphide (H 2S). Many chemical carriers have individual cargo pumps and pipelines dedicated to each cargo tank. However, on ships where cargo tanks share cargo, vapour or i nert gas lines with other tanks, furth er precautions should be taken to ensure effective isolation of the tank prior to any work commenci ng. This may require valves to be lashed closed or the fitti ng of blanks. Whenever cargo pumps, pipelines or valves are to be opened, th ey should first be cleaned and gas freed. Even after cleani ng, care is always required whenever a pipeline or equipment withi n a tank is open ed up, since cargo residues may still be released. Personnel worki ng on pipelines, pumps and other equipment within a cargo tank should be aware of the last cargo carried and wear the appropriate PPE for that cargo. If unexpected quantities of liquid or vapour are released, the tank should be evacuated.

191

Hot work i n an enclosed space should only be carried out when all applicable regulations and safety requirements have been met and a hot work permit has been issued in addition to the tank entry permit. A full risk assessment should also be carried out and risk mitigation measures implemented before any work commences (see Section 2.14).

9.8

ENTRY INTO AN ENCLOSED SPACE WHERE THE ATMOSPHERE IS KNOWN OR SUSPECTED TO BE UNSAFE Enclosed spaces that have not been tested should be considered unsafe for persons to enter. If the atmosphere within the space is known or suspected to be unsafe, the space should only be entered for emergency purposes. The number of persons entering the space should be the minimum compatible w ith the scope of the work to be performed. When toxic vapour detection equipment is not available for products that require such detection, the IBC Code allows flag administrations to permit tank entry subject to the provision of additional BA equipment and an entry being made in the IMO Certificate of Fitness regarding th e particular product and the required provisions. Entry into an enclosed space which is known or suspected of bei ng unsafe should always be considered a non-routine operation. This should only be carried out under the direct supervision of a senior officer (see Section 3.8.2). All personnel entering the enclosed space should wear suitable breathing apparatus, either of the air line or self-contained type, and should be trained in its use. Where an air line type is used a back up air supply should be provided i n the event that the air line fails. Air purifying respirators or filter masks should not be used as they do not provide a supply of clean air from a source independent of the atmosph ere withi n the space and do not protect against an oxygen deficient atmosphere. Additional PPE may be required, particularly if there is the possibility that personnel entering the space might come into contact w ith toxic or corrosive substances. The requirements of the tank entry permit should be complied with as far as practicably possible. For those elements where compliance is not possible a full risk assessment should be carried out to identify the additional risks involved. Before entry, the supervising officer should ensure that all risk mitigation measures agreed to in the risk assessment are implemented. The following should always be addressed prior to entry into an enclosed space w'here the atmosph ere is known or suspected to be unsafe: Safety equipment and PPE should be suitable for the intended purpose; Breathing apparatus should be checked, tested and confirmed to be i n good working order; All personnel involved are aware of the planned activity and the action to take in an emergency; The requirements for PPE also apply to those supervising the operation from outside the enclosed space. Persons standing close to the entrance to an enclosed space may also be exposed to the atmosph ere from within the space; Rescue equipment that is suitable for the intended space should be rigged and ready for immediate use close to the entrance of the enclosed space; The rescue team should be standing by, fully equipped w ith PPE and breathing apparatus, and ready to provide immediate assistance in the event of an emergency; and

If an explosive atmosphere is present, or suspected, the risk assessment should address potential ignition sources.

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Entry into an enclosed space where the atmosphere is known or suspected to be unsafe should only be conducted in an emergency (see Sections 3.7 and 3.8 and also Chapter 10).

9.9

RESCUE FROM CARGO TANKS AND OTHER ENCLOSED SPACES

9.9.1

GENERAL It is essential that regular drills and exercises to practise rescue from enclosed spaces are carried out, and that all members of a rescue team know what is expected of them. When personnel are in need of rescue from an enclosed space, the first action from the person assigned as the attendant should be to raise the alarm. Although speed is often vital in the interest of saving life, rescue operations should not be attempted until assistance has arrived and a planned approach can be made. Over the years, there are many examples of lives having been lost through hasty, ill prepared rescue attempts.

9.9.2

PREV ENTING ENCLOSED SPACE ACCIDENTS Enclosed space accidents can be avoided with good planning as described in this chapter. In addition, providing all crew members with a suitable safety harness when working within an enclosed space will greatly speed up the rescue effort should an accident occur. Safety lines should be used unless, because of the particular circumstances, their use is considered impractical.

9.9.3

RESCUE AND RECOVERY ORGANISATION Enclosed space rescue procedures should be well planned and regular drills held to improve effectiveness. There are a number of issues that rescue procedures should address. Team composition The rescue team should comprise a dedicated team of personnel drilled and trained as appropriate in all aspects of enclosed space rescue including in the use of resuscitation equipment. All team members should be familiar with the ship's SMS, and its operating and emergency procedures. Although a dedicated team offers major advantages it is essential that back up personnel are also identified in case a member(s) of the dedicated team is unavailable. Team rol es The Rescue team should consist of the following personnel: Team leader - this should be a senior officer. The role will be to direct the rescue effort, therefore the leader should not form part of the team that enters the enclosed space; Entry team - the number of entry team personnel should be kept to a minimum. However, at least two persons should enter the space to carry out the rescue; and Back up personnel - these should be employed to rig the rescue equipment, ensuring that the entry team have the equipment and support necessary to carry out their task and to monitor the enclosed space atmosphere. One crew member should be assigned to assist the rescue team leader with communications and to maintain a record of events.

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Regular training of the emergency rescue team is essential to ensure a successful enclosed space rescue. Emergency rescue team members should be: •

Prepared for the physical and technical demands of enclosed space rescue;

•

Well trained in all rescue team duties;

•

Familiar with the use and deployment of rescue equipment that should be of a size and weight to allow its ready deployment into the enclosed space and placement in any location where work may take place; and

•

Capable of fulfilling any role within the rescue team.

Depending on the overall crew composit ion and assessment of the i ncident some roles can be executed by a single person who may carry out more than one function.

9.9.4

THE RESCUE OPERATION The person on watch at the entrance to the enclosed space (attendant) should, as. s.oon as they are aware that a person in the space is in difficulty, immediately raise the alarm. It is therefore essential that a method of raising the alarm is agreed and tested in advance together with a means of communicating the details of the emergency. It is also essential that the rescue team is advised regarding the nature of the accident and how many persons are affected. Rescu e team personnel should proceed immediately to the entrance to the enclosed space together with any additional equipment. No one should enter the space without the team leader's permission. Unless it has been positively assessed that the atmosphere i n the enclosed space is safe to breath, the entry team should in addition to wearing appropriate protective equipment use breathing apparat us. Only after a full test has confirmed that the enclosed space atmosphere is s.afe to enter (see Section 9.4) should the entry team proceed without breathi ng apparatus.

In an emergency rescue, the atmosphere of an enclosed space should always be considered to be unsafe unless confirmed otherwise.

On reaching the casualty the entry team should ascertai n if the casualty is still breathing. If the casualty is not breathing the entry team should remove the casualty from the space as soon as possible for resuscitation .

If the casualty is breathing, any injuries should be assessed before the casualty is removed from the space. If the condition of the atmosphere in the enclosed space is not verified as safe, the casualty should be provided with a safe independent air supply in the enclosed space. During the incident the team leader and back up personnel should : Monitor the rescue team and ensure the provision of spare air supplies; Rig rescue equipment such as hoists; Monitor the atmosphere of the space; Communicate w ith the vessel's command team; and Arrange additional lighting, ventilation and i mprove access to the space, as appropriate. Removal of the casualty should be carried out u tilising the most appropriate equipment such as stretchers, lifting harnesses and hoisting apparatus.

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9.9.5

RESCUE AND RECOVERY EQUIPMENT The following equipment is recommended to ensure a successful rescue from an enclosed space: Hoist A dedicated hoist for enclosed space rescue operations should be rigged before entry or be readily available. When selecting a suitable hoist the following should be considered: The Safe Working Load (SWL) should be appropriate to the anticipated lifting requirement, i.e. maximum weight of a casualty including stretcher and resuscitation equipment. The rescue team should be aware of whether or not the SWL allows for the lifting of multiple personnel; It is important that the hoist can be properly positioned and secured over any enclosed space entrance from which a casualty may need to be lifted; and The hoist should be portable, lightweight and easy to assemble at the site. Should a powered hoisting motor be fitted, which should be safe to use in the operating environment, this should be capable of lifting the casualty in a controlled manner. Stretcher When selecting a stretcher for enclosed space rescues the following should be considered: In enclosed spaces where a vertical lift is required the stretcher should be able to secure the casualty properly and prevent head injury; The stretcher and casualty should be able to pass through the enclosed space openings and around tight corners; and The stretcher should be capable of being handled by rescuers wearing full protective equipment. Breathing apparatus The following should be considered: The design of the apparatus should be lightweight and enable the wearer to access confined spaces without the need to remove it; and Radio communication should be possible when using the breathing apparatus. Resuscitation equipment The following should be considered: It should be light, portable and preferably capable of being recharged on board; It should be provided with a manual and automatic resuscitation system; and Due to the potential fire risk, pure oxygen should not be used for resuscitation in an enclosed space. Communication equipment An effective system of communication between the team leader and the entry team should be agreed. It is strongly recommended that two way radios are used. Other equipment The following equipment should also be considered for use during an enclosed space rescue: Personal Protective Equipment (PPE) - protective suits, head and eye protection, gloves and safety boots suitable for the expected hazards to be found within the space; Atmosphere testing equipment; Where practical, harnesses and lifelines should be used; Extra lighting including portable lighting; and Additional ventilation capacity. Care should be taken if the space contains a dangerous atmosphere as this could affect the rescue team standing by at the entrance to the space.

19S

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CHAPTER 10

EMERGENCY PROCEDURES

10

EMERGENCY PROCEDURES

This chapter describes how emergency response procedures should be organised and implemented on board chemical tankers. Particular attention is paid to fire-fighting and to incidents involving polluting, toxic or corrosive cargoes.

10.1

Introduction

10.2 10.2.1 10.2.2 10.2.3 10.2.4

Emergency Organisation Emergency team Supporting crew Emergency organisation in port Vacating a berth or terminal in an emergency

10.3

198

Fire-Fighting Equipment General Water Foam Foam monitors Carbon dioxide Halon

10.3.1 10.3.2 10.3.3 10.3.4 10.3.5 10.3.6 10.3.7 10.3.8 10.3.9

Dry powder Inert gas systems Fire-fighting clothing

10.4 10.4.1 10.4.2 10.4.3 10.4.4

Responding to Emergencies Emergencies involving fire Emergency response to fire Fires involving chemicals Action to take in the event of fire

TANKER SAFETY GUIDE (CHEMICALS)

10.5 10.5.1 10.5.2 10.5.3 10.5.4

Other Emergencies Chemical cargo spills Deck valve and deck pipeline leakage Tank leakage within the vessel Emergency discharge or jettison of cargo

10.6

Notification of Spillage

10.7 10.7.1 10.7.2 10. 7.3 10. 7.4

Exposure to Chemicals Planning

10.7.5

Medical first aid guides Toxic cargoes and antidotes Medical first aid after exposure to chemicals Emergency information on MSDS

10.8

First A id and Further Care

10.1

INTRODUCTION It is impossible to predict the nature of every potential emergency that may occur on a chemical tanker. Standard emergency procedures should however be developed and kept available for immediate implementation, so that action can be taken quickly and decisions on how to tackle any additional problems can be made in an orderly manner. The ship's emergency plans and procedures should be aligned with a broader plan held by the vessel 's operator. The procedures developed should anticipate and plan for the types of risks that may be encountered within the vessel's trading area. The operational quality and emergency preparedness of shore termi nals should also be taken into account. Crews of chemical tankers should be trained and be prepared to tackle emergencies and particularly cargo related emergencies such as chemical fires, chemical reactions, toxic vapour releases, leaks and spills, both at sea and in port. Personnel that will be directly involved in tackling such emergencies should be familiar with the vessel's emergency procedures and conti ngency plans. Chapter 3 provides further i nformation on familiarisation and training requi rements. All personnel should be familiar with the muster list detailing their emergency response duties.

10.2 EMERGENCY ORGANISATION Company procedures should be standardised throughout the chemical tanker fleet, as appropriate, to ensure that a uniform organisational structure is implemented on board all company vessels. It is recommended that the emergency procedures include and support a designated emergency team which should be made up of competent, experienced and physical ly fit members of the vessel's crevv. The remainder of the crew should be arranged in support roles whose primary task will be to support the emergency team and provide additional resources as required.

10.2.1 EMERGENCY TEAM The team's primary task w ill be to take whatever action is necessary to respond to the emergency situation. Drills and exercises should focus on a variety of emergency scenarios expected on chemical tankers to ensure that all crew become familiar with the ship's emergency response procedures and equipment. Duties in the team should be rotated to encourage team work, flexibility and an overall understanding of the on board emergency procedures.

10.2.2 SUPPORTING CREW Supplementary teams should be organised from the remainder of the vessel's crew to support the emergency team and to ensure the safety of the vessel. Supporting crevv will need to be designated to provide, amongst other thi ngs: Back up to the emergency team; Management of the emergency response; Navigational safety; Maintenance of ship's systems; Communications; Medical and first aid assistance; and Preparation of the lifeboats in case abandonment of the vessel is required .

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10.2.3 EMERGENCY ORGANISATION IN PORT The Master will remain i n control of operations with any shore based support considered to be supplementary to the ship's own organisation until and unless the situation on board renders this impractical. Sufficient personnel should be retained on board at all times when the vessel is in port to deal with any emergencies. The ship's emergency response procedures should always be initiated, even if local fire or emergency organisations arrive. The emergency plans, which should include emergency evacuation procedures, have to be as effective in port as at sea. All procedures and arrangements therefore have to be developed w ith this in mind.

10.2.4 VACATING A BERTH OR TERMINAL IN AN EMERGENCY An emergency may make it necessary to vacate a berth or terminal. The Master should consider the risks i nvolved to ensure that moving the vessel does not increase the risk to ship and shore personnel, the vessel itself, the terminal, other vessels, adjacent installations or shore facilities.

If the Master decides to vacate the berth, the port authority, terminal or local emergency response organisation should wherever possible be informed. If the emergency situation allows, the Master should discuss with the shore authorities the possibility that the ship may need to leave the berth. Notwithstanding the above, the decision to vacate the berth will primarily be based on the need to ensure the safety of life and protection of the environment.

10.3 FIRE-FIGHTING EQUIPMENT 10.3.1 GENERAL Fire on board ship is one of the most serious emergencies that can occur. Chemical tankers normally have two mai n fire-fighting media available, typically water and an alcohol resistant foam system. The minimum capacity and coverage of these systems are dictated by IMO requirements. In addition, some chemicals have properties that require special fire-fighti ng equipment to be installed, such as a water sprinkler system. The provision of defined fire-fighting equipment to tackle a chemical fire is a requirement for gaini ng the !MO Certificate of Fitness. The best way of dealing with a cargo fire in a tank is frequently by means of a smothering agent, such as foam, carbon dioxide, or in some cases dry chemical powder, coupled with sealing off the tank and cooling adjacent areas or spaces, wherever possible.

10.3.2 WATER Water is the most commonly used fire-fighting cooling medium, but has a limited extinguishing effect on most chemical fires. If used, water should be applied as a spray or water fog, or used in combination with a foam compound. Water should primarily be used for cooling the chemical itself by cooling adjacent structures such as bulkheads and decks, and for reducing the concentration of vapours in the air. Water spray nozzles also help to protect fire-fighters by formi ng a screen (a water sheet) between the fire-fighter and the fire. A jet of water should never be used as this may spread the fire by splashi ng or overflow or through agitating the surface of the liquid exposing more fuel to the fire. In an intense fire the water will rapidly boil, i ncreasi ng the agitation of the chemical.

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10.3.3 FOAM Chemical tankers carry foam as the main fire-fighting medium, and most use alcohol resistant or multi-purpose foams. The correct type of foam concentrate will be important in determining the range of cargoes that can be carried under the IMO Certificate of Fitness. Foam suppresses fire by forming a coherent smothering blanket over the burning liquid that cuts off the oxygen supply from air. Foam also has a cooling effect on the surface temperature of the liquid. Foam conducts electrical current and should not be used where high voltage current is involved, unless the electricity supply has been shut off. During the application of any foam, a water screen (see Section 10.3.2) may be used to protect fire-fighters from radiant heat to permit closer approach to the fire. Care should be taken to prevent water falling onto the foam and reducing its effectiveness.

10.3.4 FOAM MONITORS Foam monitors are dedicated devices for delivering large volumes of foam quickly. As a principal fire-fighting tool in the event of a fire in the cargo area, the operational readiness of foam monitors is essential. Every opportunity should be taken to practise their use. This is especially so for remotely controlled monitors.

Foam has a limited effect once fires become established and flames will then start to 'push' extinguishing foam away, reducing its effectiveness.

10.3.5 CARBON DIOXIDE Carbon dioxide is an excellent smothering agent for extinguishing fires when used in conditions where it can be contained and not be widely diffused. However, it has poor cooling qualities and the possibility of re-ignition by hot surfaces should be considered. Due to the possibility of static electricity generation, carbon dioxide should not be injected into any space containing a flammable atmosphere which is not already on fire. When used as a fire-fighting medium, carbon dioxide is asphyxiating and cannot be detected by sight or smell.

10.3.6 HALON The installation of halon fire-fighting installations is prohibited for new ships. However, ships built before July 1992 may retain halon fire extinguishing systems on board. Halogenated hydrocarbons are vaporising liquids which have a flame inhibiting effect, similar to dry chemical powder, and also have a slight smothering effect. The different halon liquids available are identified by a system of halon numbers and these identify their intended usage. The environmental disadvantages of halons, particularly their effect on the planet's ozone layer, are well known, and modern ships are not fitted with them. However, where halons are fitted, their use in an emergency may be necessary and appropriate to save lives or the ship. As with carbon dioxide, halons and other chemical fire extinguishing gases are most effective in enclosed spaces, where they will not be widely diffused. All halons are considered to be toxic to some degree because contact with hot surfaces and flame causes them to break down, yielding toxic substances. After a fire has been extinguished, it is necessary to use suitable breathing apparatus to enter the space.

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10.3.7 DRY POWDER Dry powder is an effective fire-fighting medium, which works by decomposing under heat into a nonflammable gas. In order to allow effective application, it is important that the powder is not damp or compacted. Discharged from an extinguisher as a free flowing cloud, dry powder can be effective in dealing initially with a fire resulting from a liquid spill in a confined space. Protection against the inhalation of powder may be necessary when used in a confined space. Dry powder is especially effective on burning liquids such as liquefied gas, or liquids escaping from leaking lines and joints, and burning liquids on vertical surfaces, for example diesel equipment fires. It is a non-conductor and thus suitable for use in dealing with electrical fires. It should be directed into the flames. Dry powder has a negligible cooling effect and so may not give protection against possible re-ignition from a hot surface. Certain types of dry powder can cause the breakdown of a foam blanket, and only those known to be compatible should be used in conjunction with foam.

10.3.8 INERT GAS SYSTEMS The purpose of an inert gas system is to prevent cargo tank fires or explosions, and to separate the cargo from the air. It is not intended as a fixed fire-fighting installation. However, in the event of a fire the system may be of assistance.

10.3.9 FIRE-FIGHTING CLOTHING Personnel directly involved in fighting a chemical fire should wear correct Personal Protective Equipment. Many chemicals will release toxic fumes when burning, and breathing apparatus should be worn by fire-fighters to guard against inhaling toxic vapours or dense smoke. Advice on personal protective clothing for chemical hazards is contained in Section 3.11 of this Guide. All protective clothing should be kept serviceable and dry, and should be properly fastened while being worn. Protective clothing should be stowed ready for immediate use with designated breathing apparatus.

10.4 RESPONDING TO EMERGENCIES 10.4.1 EMERGENCIESINVOLVING FIRE Introduction The prevention of fire on board chemical tankers is a major consideration in their design. Because of the nature of the cargoes carried, fire poses a very serious threat to the crew and the vessel. It is therefore essential that the crews of chemical tankers understand the principles of fire prevention and fire-fighting. Although fire is a risk to the safety of the vessel itself, it can also precede further emergencies, including explosion, damage to the vessel and the generation of toxic fumes.

In the event of a serious and uncontrolled cargo fire the Master should consider ordering the immediate abandonment of the ship.

Combustion Combustion is a chemical reaction, or a series of reactions, in which heat and light can be produced . When the rate of reactions is high, combustion occurs at a rapid rate with usually both heat and light being emitted and a 'fire' is said to exist.

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Fire triangle

Fire requires a combination of fuel, oxygen and heat (a source of ignition) in the right proportions to start and maintain combustion. Removal of any one of these three elements will extinguish the fire. It is helpful to imagine these three essential factors as forming the sides of a triangle. Fire-fighting aims to remove one, two or all three of these sides of the triangle. Removal of heat by cooling the fire, cutting off the supply of fuel or reducing the oxygen level in the atmosphere around the fire, are all effective means of extinguishing a fire.

10.4.2 EMERGENCY RESPONSE TO FIRE Introduction

Immediate response to a fire is essential. The person discovering a fire should immediately raise the alarm and take suitable responsive action, as appropriate. The fire should be assessed and details, including its location, should be provided to the emergency team. On report of a fire, the vessel's emergency response plan should be activated. Fire-fighting

A fire, including a chemical fire, requires a combination of three elements: fuel, oxygen and heat or a source of ignition (see fire triangle above). The principal means of controlling and extinguishing a fire is to remove one or more of the elements, either by removal of the fuel, by cooling, or by excluding a supply of oxygen (air). In chemical fires, the source of ignition may be heat from a reaction within the chemical itself or from a reaction after mixing chemicals. A supply of oxygen may be released from the chemical through heating by the fire. Therefore fire-fighting will be made more difficult.

10.4.3 FIRESINVOLVING CHEMICALS Some liquid chemicals have properties which necessitate fire-fighting techniques that differ from those used on simple oil fires. The following list indicates some of these properties: Some chemicals are soluble in water and at certain concentrations the solution may be flammable; Some chemicals which are soluble in water will destroy normal foam, so alcohol resistant or dual purpose foam is required; Some chemicals are heavier than and insoluble in water and can be extinguished by a carefully applied blanket of water; Some chemicals do not require an external supply of oxygen to sustain fire; Some chemicals react with water to produce heat and thus give off increased amounts of flammable (and in some cases toxic) gases; Some chemicals evolve large volumes of toxic vapours when heated; Some chemicals evolve large volumes of toxic vapours when burning; and The comparatively low auto-ignition temperature of some chemicals increases the chance of re-ignition. The MSDS should draw attention to a chemical's reaction to fire and indicate the correct fire-fighting medium and any special precautions to be taken by fire-fighters. A fire involving chemicals is most likely to occur in a cargo tank or on the cargo deck. In the case of a spill or tank overflow, or a side shell rupture, the fire may spread to the surface of the water surrounding the ship.

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10.4.4 ACTION TO TAKE IN THE EVENT OF A FIRE The following sequence of events should be considered for inclusion in the vessel's emergency procedures for tackling a fire: Activate the alarm; Stop cargo operations - close all valves and hatches; Activate ship's emergency plan; Organise fire-fighting teams;

If alongside a berth, alert terminal staff (and agent if time allows) and request them to alert port authorities;

If at anchor in port, alert the port authorities; If other ships or craft are alongside, alert them and instruct them to depart immediately; Identify the chemical or chemicals involved, and any ch emicals that may be at risk if the fire spreads; Select the fire-fighting equipment and fire extinguishing agent to be used; and Be alert to the risk of toxic fumes entering the accommodation, and that an evacuation of non-essential crew may be necessary. The ship's general alarm should be raised and, if alongside, the terminal should be notified with details of the chemicals involved. The terminal control room should be requested to summon any necessary outside assistance and, if appropriate, activate their emergency procedures. Any cargo handling, ballasting, tank cleaning or bunkering operations should be stopped immediately and all valves closed. Any craft alongside should be i nstructed to leave immediately. Decks, bulkheads and other structures in the vicinity of the fire, and adjacent tanks which contai n flammable cargoes or are not gas free, should be cooled with water and, if appropriate, inerted. Chemical cargo fires may initially be small. However, there is a significant risk that without the deployment of immediate and sufficient fire-fighting resources such a fire will develop resulting in one or a combination of the followi ng: Explosion; Boiling liquid Expanding Vapour Explosion (BLEVE);20 and/or Damaged/unavailable equipment and systems.

If at sea, the vessel should be manoeuvred so as to restrict the spread of the fire.

10.5 OTHER EMERGENCIES The following sections provide guidelines for emergencies that may occur involvi ng chemical tanker cargoes.

10.5.1 CHEMICAL CARGO SPILLS The biggest risk of a cargo spill is during cargo handling operations, either due to an equipment failure or improper handling procedures. Cargo spills are therefore most likely to happen i n port. In the event of a spill, the following actions should be taken immediately: Activate the alarm; Stop all cargo operations and close valves and hatches; and Activate ship's emergency plan. 20 Boding Liquid Expanding Vapour Explosion (SL.EVE). The phenomenon which occurs when a vessel cootaning a pressurised liquid substant~ above its boiling point is ruptured, releasing the contents explosively.

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If alongside a berth, notify the terminal staff of the chemicals involved and the possible risk to personnel. Further actions include: Notify local port authorities, usually through the terminal; Prohibit smoking and use of naked lights throughout the ship; Clear all non-essential personnel from the area; Close all accommodation access doors, and stop all non-closed circuit ventilation; Arrange for main engines and steering gear to be brought to stand by; Erect barriers to secure contaminated areas; Minimise potential for pollution; and Plan for decontamination of exposed personnel. The primary factor affecting response w ill be the chemical or chemicals involved, but the action to be taken depends on the circumstances of the spillage, as well as its size and location. If there is a possibility of cargo or cargo vapour entering any accommodation or engine room air intake, appropriate preventive steps should be taken immediately. As a general rule, there should be a full initial response to any spill with the emergency party wearing the appropriate protective clothing and breathing apparatus. In most cases it is better to overreact than to delay action. The safety of personnel, the ship and environmental protection will take priority over all other factors. If it is possible and safe to do so, the released liquid should be pumped or washed into a slop tank or other containment, or collected for safe disposal using absorbent material. However, if this cannot be achieved safely and there is imminent danger to the safety of personnel or the ship, the spillage should be washed overboard with very large amounts of water. If at sea, the tanker should be manoeuvred so as to disperse vapour away from the ship's accommodation. Should the Master consider it necessary to wash a cargo spillage overboard thi.s should be carried out using large quantities of water from as far away as practicable. A spray nozzle should be used and not a direct jet of water. The emergency team should wear appropriate protective equipment, approach the spill from upwind and direct the spray of water to the edge of the spill, gradually working towards the centre. The use of water on a fuming acid and other strong acids will initially cause a vigorous reaction that will cause increased fuming. However, this shou Id be temporary and the spillage will normally be dealt with rapidly. If at sea, the ship should be turned off w ind. For small, localised and contained spills, it may not be necessary to implement all the action points in the ship's contingency plan. However, the Master should always keep in mind the local circumstances, the nature of the chemical involved, and the potential harm to personnel, the ship's structure and the environment.

10.5.2 DECK VALVE AND DECK PIPELINE LEAKAGE If leakage develops from a deck pipeline, deck valve, cargo hose or metal arm, operations through that connection should be stopped and the situation treated as an emergency until the cause has been identified and the defect remedied. Permanent means for the retention of any slight leakage at ship and shore connections should be provided. Operations should not be restarted until the fault has been rectified and all hazards from the released cargo eliminated. If a pipeline, hose or arm bursts, or if there is an overflow, all cargo and bunker operations should be stopped immediately and the situation treated as a cargo spill.

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10.5.3 TANK LEAKAGE WITHIN THE VESSEL leakage from a cargo tank i nto void or ballast spaces may cause damage to the ship's structure or equipment, and may create an explosive atmosphere and a risk to personnel. The actions to be taken may differ depending on the product involved and other circumstances such as the weather, but should as a minimum include the followi ng: Identify the products involved and the risks associated with them; Clear the area of all non-essential personnel; Identify the location of the leak; Transfer the product in the leaking tank to an em pty tank, if possible; Notifying port and local authorities, and ship's operators, as appropriate; and Commence remedial actions. Spills in confined spaces such as pumprooms should, where practicable, be first contained and then treated and collected for safe disposal. An acid spillage should be prevented from entering mild steel areas of the ship as rapid corrosion can occur. In extreme cases the consequent hull corrosion can cause the ship to si nk. l eakages from one cargo tank to another, or multiple leakages where there is a risk of mixing incompatible chemicals, should always be treated carefully. Where time allows, expert advice should be sought as to the possible risks i nvolved. A non-cargo space that has had a chemical leaking into it should be treated as a cargo space, and the same precautions taken. It should be cleaned and gas freed before any attempt is made for repairs. Remedial measures should be decided upon after consultation with th e operator. Full enclosed space entry procedures as specified in Chapter 9 should be followed.

10.5.4 EMERGENCY DISCHARGE OR JETIISON OF CARGO The decision to jettison cargo is an extreme measure, justified only in an emergency as a means of saving life at sea or where the integrity of th e ship is at risk. A decision to jettison cargo should not be taken until every alternative option has been considered in the light of available information on stability and reserve buoyancy.

If it is necessary to jettison cargo there will be a possibility of releasing large amounts of flammable or toxic vapours. The following precautions are recommended: Where possible, and if time permits, fully discuss the planned action with the company; Engine room personnel should be alerted. Consideration should be given to changing over engi ne room sea water intakes from high to low level; Discharge should take place through a sea valve and where possible on th e side opposit e to the engine room i ntakes; All non-essential i nlets should be closed;

If discharge has to be from the deck level, flexible hoses should be rigged to extend below the water surface; All safety precautions relating to the presence of flammable or toxic gas i n the vicinity of the deck should be observed; A radio warning should be broadcast for the information of ships nearby; and A complete detailed record of events and accompanying evidence should be meticulously made and maintained in the event of any discharge.

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10.6 NOTIFICATION OF SPILLAGE Any incident, accidental or deliberate and whether at sea or in port, that causes or will probably cause a release of a cargo or noxious liquid substance into th e sea should be reported to the proper authorities. Each ship will have its own Shipboard Mari ne Pollution Emergency Plan (SMPEP) covering spillage of noxious liquids which will contain advice.

10.7 EXPOSURE TO CHEMICALS Exposure of personnel to toxic or corrosive fumes or liquid should always be treated as an emergency. First aid should be administered as indicated in the product MSDS (see also Section 10.8).

10.7.1

PLANNING Several third party companies provide a 24 hour, 7 day a week, medical advice service additional to that which may be provided by coastal states. Companies should develop policies and procedures for the care for and protection of their seafarers.

10.7.2 MEDICAL FIRST AID GUIDES The two fundamental guides for medical first aid on board ships, which give advice on dealing with exposure to toxic cargoes, are th e International Medical Guide for Ships (IMGS) and the Medical First Aid Guide for Use i n Accidents Involving Dangerous Goods (MFAG). Both are published jointly by IMO, ILO (the International Labour Organization) and WHO (the World Health O rganization). MFAG is the Chemicals Supplement to the IMGS and contai ns specific guidance for rescue, treatment and recommended medicines and equipment. The IMGS is intended for all ship types and provides guidance and advice regarding any person exposed to toxic or corrosive cargoes or those who in any way exhibit symptoms of being exposed. Such personnel should be treated according to the advice in the MFAG and seen by a doctor as soon as practicable. Medical advice should be sought immediately. When the ship is at sea advice is available by radio or by medical services by phone. Assistance may also be available from another ship with a doctor on board. MFAG contains an emergency action flow chart which assists with diagnosis and provides references to tables providing treatment advice. The tables in MFAG provide detailed guidance on signs and symptoms and treatment guidance taking into account the List of Medicines and Equipment recommended by MFAG. The vessel's emergency plans and procedures should ensure that: Procedures are in place to address a first aid emergency on board and for t h e recovery and treatment of a casualty; Designated crew members are trained to administer first aid; Sufficient medicines and first aid equipment are available to treat crew mem bers exposed to toxic or corrosive cargoes; and Specific antidotes or other treatments are available for the cargoes carried.

10.7.3 TOXIC CARGOES AND ANTIDOTES For some toxic cargoes antidotes are available in case personnel are accidently exposed to cargo liquid or vapour. Should antidotes be required they should be provided to the ship before loading cargo and be complete with detailed instructions together with any other equipment that may be required for their use.

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10.Z4 MEDICAL FIRST AID AFTER EXPOSURE TO CHEMICALS The Master should evaluate the seriousness of the exposure and, if i n doubt, immediately seek outside medical attention and advice. In case of exposure the casualty should be immediately moved from the affected area. This is particularly important if there is a risk of further exposure. Procedures should ensure that personnel involved in recovering a casualty from exposed areas are themselves suitably protected.

An MSDS sheet for the chemical that the casualty has been exposed to should be attached to or remain with the casualty prior to medical evacuation.

10.ZS EMERGENCY INFORMATION ON MSDS The information on the MSDS is of vital importance for the diagnosis and treatment of a casualty and should be immediately referred to when chemical exposure has occurred. See Appendix 5. The MSDS will contai n i nformation which is relevant in case of chemical exposure, i ncluding the following: Emergency telephone number where more information can be obtained if necessary; First aid measures, in case of: Inhalation; Skin contact; Eye contact; Ingestion; Most important symptoms/effects, acute and delayed; and Immediate medical attention, special treatment; Exposure controls/personal protection: Individual protection measures; Respiratory protection; Hand protection; Eye protection; Protective clothi ng; and Thermal hazards; Toxicological information: Likely routes of exposure; Skin corrosion/irritation; Serious eye damage/irritation; Respiratory irritation; Respiratory or ski n sensitisation; and Aspiration hazard.

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10.8 FIRST AID AND FURTHER CARE The key priorities that should be remembered when reacting to a casualty are: Raising the alarm; Do not become the next victim; Removing the casualty from the danger but only if wearing appropriate PPE; Using breathing apparatus if there is any suspicion of toxic gases or vapours in the area; Referring to the MSDS immediately for treatment advice; Referring to MFAG, as appropriate; If possible moving the casualty to a decontamination shower, if appropriate; The removal of PPE should only follow thorough decontamination. Care should be taken to avoid cross contamination; Removing the victim's clothing and shoes while under the shower; If even a minute quantity of chemical has entered the eye, it must be flushed immediately with plenty of water for a minimum of 15 minutes; Treating the casualty, seeking professional medical advice, if required; and Continuing to monitor and care for the casualty.

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APPENDICES

APPENDICES

212

APPENDIX 1

VISITOR INFORMATION CARD

APPENDIX2

HOT WORK PERMIT

APPENDIX 3

SHIP/ SHORE SAFETY CHECKLIST

APPENDIX4

SHIP/ SHORE SAFETY CHECKLIST GUIDELINES

APPENDIX 5

MATERIAL SAFETY DATA SHEET (MSDS)

APPENDIX6

INHIBITED CARGO CERTIFICATE

APPENDIX 7

ENCLOSED SPACE ENTRY PERMIT

APPENDIX8

CARGO HOSE RECORD

APPENDIX 9

FLEXIBLE HOSE TEST CERTIFICATE

APPENDIX 10

PPE MATRIX

APPENDIX 11

RELEVANT INDUSTRY PUBLICATIONS

TANKER SAFETY GUIDE (CHEMiCALSJ

INDEX A Access to the ship

2.4, 6.5.4, Appendix 3, Appendix 4

Acids

1.2.8, 1.6.2, 1.6.3, 1.6.5, 1.7.1 , 1.7.2, 5.4.4, 5.13.3, 6.7.2, 8.7.2, 10.5.1,

Additives

1.2.3, 1.6.2, 8.5.4, Appendix 4

Air conditioning

2.7.4, 6.5.4, Appendix 3, Appendix 4

Air pollution

4.3.3

Air supply

3.11 .6, 3.11 .1 3, 3.1 1.1 4, 5.3.3, 9.2, 9.8, 9.9, Appendix 7

Air supply to instruments and controls

5.3.3

Alarms

5.3.4, 5.3.5, 5.5.3, 5.1 6, 6.4.5, 6.6, 6.7.2, 6.7.3, 6.7.6, 6.7.9, 6.7.1 0, 6.7.16, 7.3, Appendix 1, Appendix 3, Appendix4

Alkalis

1.6.2, 1.6.5, 1.7.1

Asphyxia

Definitions, 1.6.3, 1.6.4, 3.7.1, 9.2.3, 10.3.5

Atmosphere control

2.1 0.1, 2.14, 2.15, 2.1 6, 3.1 1.1, 4.4.3, 4.5, 5.4, 5.1 3, 6.3.5, 6.7.8, 6.7.20, 6 8.5, 9.3

Atmosphere in enclosed spaces

9.3

Auto-ignition

Definitions, 5.1 5.1, 10.4.3, Appendix 4, Appendix 5

Automatic shutdown systems

5.3.2, Appendix 3, Appendix 4

B

262

Ballast

1.6.4, 2.6.1 , 2.1 1, 2.14.4, 4.6, 5.16, 6.4, 6.5.4, 6.6, 6.7.6, 6.7.1 5, 6.8.6, 6.9.7, 9.1, Appendix 3, Appendix 4

Ballasting

2.11 , 2.1 6, 2.17, 4.1 , 4.3.2, 4.6, 6.4.2, 6.7.6, 6.7.1 5, 6.8.6, 10.4.4, Appendix 3, Appendix 4

Ballast tank

1.2.3, 1.6.4, 5.1 6, 6.7.15, 6.8.1 , 9.1 , Appendix 3, Appendix4

Barge

1.8.1 , 3.5, 6.9.1 , Appendix 1

Battery powered equipment

2 .1 3.4, 5.4.2, Appendix 4

TANKER SAFETY GUIDE (CHEM,CALS)

Bilges

2.10.1, 5.5.3, 5.16, 6.4.5

Bi-metallic thermometers

5.3 .7

Blank f langes

4.4.2, 6.4.5, 6.7.2, Appendix 3, Appendix 4

Blanketing

6.7.8

Boiler tubes

2.8.2

Boiling point

Definitions, 1.2.5, 1.3.2, 1.8.2, Appendix 5

Bonding

Definitions, 5.1 1.2, 5.15.3, 6.7.4

Bourdon tubes

5.3 .6

Breathing apparatus

3.11.11, 3.11 .1 3, 3.11 .1 4, 3.11 .1 6, 3.11 .1 7, 6.5.4, 6.7.2, 6.7.1 8, 7.3, 9.8, 9.9.4, 9.9.5, 10.3.6, 10.3.9, 10.5.1, 10.8, Appendix 3, Appendix 4, Appendix 7, Appendix 10

Bridge (navigation)

9.4.2, Appendix 2, Appendix 7

Bulkhead glands

6.4.5, 6.7.5

Bunkering

2.16, 2.1 7, 3.5, 3.10.8, 6.4.2, 6.4.3, 6.5.1 , 10.4.4, 10.5.2, Appendix 1, Appendix 3, Appendix 4, Appendix 7, Appendix 10

Burns

1.7.1 , 6.7.21, 9.7

c cables - power/electrical

2.14.5, 5.1 5.3, Appendix 3, Appendix 4

calibration

5.3 .1 , 5.3.6, 5.4.2, 5.4.5, 6.4.5, 6.7.6, 9.4.1 , 9.5, Appendix 3, Appendix 4

canister - respirators

3.11.12

capacitive pressure transmitters

5.3.5, 5.3.6

carbon dioxide

1.6.3, 1.6.4, 5.4.3, 5.1 3.3, 5.13.7, 5.1 3.8, 7.2, 9.2.3, 10.3.1, 10.3.5, 10.3.6

carbon monoxide

5.4.3, 5.1 3.7, 9.2.1, 9.4.2, 9.5

cargo care during the voyage

6.8

cargo containment

1.7.1 , 4.4.1 , 6.1 , 6.7.1 8

cargo cooling

1.2.5, 1.6.2, 5.1 0, 6.3.5, 6.4.3, 6.4.5, 6.8.3

cargo handling equipment

5.3 .1 , 6.9.1 , 6.9.2, 8.1 0.2

263

Cargo heating Cargo hoses

4.3.1 , 5.3.7, 5.1 0, 6.3.4, 6.3.5, 6.4.3, 6.4.5, 6.8.3 1.5.5, 5.1 4.1, 5.14.2, 5.1 4.4, 6.7.4, 6.7.18, 6.9.7, 6.9.8, Appendix 3, Appendix 4

Cargo information sharing

6.4.2, 6.4.4

Cargo leakage

2.1 0.1, 5.5.2, 5.7, 6.4.5, 6.7.5, 6.8.1, 10.5.2, 10.5.3

Cargo liquid

5.9, 6.3.5, 10.7.3

Cargo loading

1.2.1 , 1.4.3, 1.4.4, 1.8.1 , 2.7.1 , 2.9.2, 2.1 1, 3.11, 4.3.1 , 4.3.2, 4.3.3, 5.2, 5.7, 5.14.1 , 6.3, 6.4.2, 6.4.5, 6.5.1 , 6.5.4, 6.7.1 , 6.7.2, 6.7.3 6.7.4, 7.4.5

Cargo operations

Definitions, 1.4.4, 2.2, 2.7.4, 2.8.1 , 2.8.3, 2.1 0.1, 3.5,

3.6, 3.10.4, 3.10.5, 3.10.6, 3.1 1.12, 4. 3, 4. 3.1 , 4. 3.3, 5.3.1 , 5.3.2, 5.3.5, 5.7, 5.1 5.3, Chapter 6, 10.4.4, 10.5.1, Appendix 1, Appendix 3, Appendix 4

264

Cargo pipelines

5.6, 5.7, 6.4.5, 8.10.2

Cargo planning

1.1 , 6.2.1 , 6.3, 6.4, 6.5.2

Cargo properties

Chapter 1, 3.11 .6, 5.14.1, 6.3.2, 6.4.3, 10.3.1 , 10.4.3, Appendix 4, Appendix 5

Cargo pumprooms

2.1 0.1, 5.5.3, 6.4.5, 6.7.5, 6.8.1, 9.1

Cargo pumps

43t5~63~6~67~84~92t97

Cargo quality control

4.4.3, 5.1 3.3, 5.13 .8, 6.3.5, 7.1 , 7.4.1 , 9.2.3

Cargo reactivity

1.6, 1.8.2, 8.3.2, Appendix 5

Cargo reaction with air or oxygen

1.6.1 , 1.6.3

Cargo reaction with construction materials

1.6.7, 1.7, 1.8, 5.12.2, 5.15

Cargo reaction with other cargoes

1.6.1 , 1.6.6, 2.10.1, 6.3.4, 6.7.1 8, 8.7.2, 10.5.3, Appendix 5

Cargo reaction with water

1.6.1 , 1.6.4, 1.6.5, 1.7.1 , 6.7.8, 8.4.1, 8.5.2, 8.7.2, 10.4.3, Appendix 4

Cargo residue

1.2.7, 1.6.6, 4.1 , 4.3, 4.3.1 , 4.3.2, 6.3.5, 6.7.1 8, 6.7.21, 6.7.22, 8.2, 8.3.2, 8.5.3, 8. 7.3, 8.10.2, 9.2, 9.2.2, 9.5, 9.7, Appendix 5

Cargo spillage

2.7, 2.9, 3.11.4, 4.4.2, 6.4.3, 6.9.6, 10.5.1 , 10.5.2, 10. 5.3, 10.6, Appendix 3, Appendix 4

Cargo tank atmosphere

2.14, 2.1 6, 3.11 .1 , 3.1 1.6, 3.11 .1 2, 3.11 .1 3, 4.5, 5.3, 5.4, 5.13, 6.3.5, 6.7.8, 6.7.20, 6.7.21, 6.8, 7.4, 8.4, 8.5, 8.10, 9.2, 9.3, 9.4, 9.5, 9.6, 9.7, 9.8, Appendix 3, Appendix 4, Appendix 7

Cargo tank materials

1.4, 1.6.7, 1.7.1 , 1.8.2, 5.1 3.5

TANKER SAFETY GUIDE (CHEMICALS)

cargo tank pressure

1.2, 1.6, 2.9, 4.5, 5.3, 5.8, 5.9, 6.3.5, 6.4.5, 6.7.6, 6.7.8, 6.7.1 6, 6.8, 7.4, 8.4.5, 8.5.6, Appendix 3, Appendix 4

cargo tank vapour space

4.4.3, 5.3.6, 5.8, 6.7.8, 6.7.9

cargo tanks

Definitions, 1.4.3, 1.4.5, 1.6.2, 1.6.3, 1.6.4, 1.6.6, 3.10.8, 3.1 1.1, 4.3, 4.3 .1, 4.3 .2, 4.4.3, 4.5, 5.1, 5.2, 5.3 .1 , 5.3.6, 5.1 2.1, 5.13.3, 5.1 3.4, 5.13.5, 6.3.5, 6.4.2, 6.4.5, 6.5.1 , 6.7.1 , 6.7.21, 6.8.6, 7.3, 7.4.1, 8.2, 8.4.1, 8.4.7, 8.7.2, 8.1 0.1, 9.1, 9.2, 9.4.2, 9.6, 9.6.1, 9.7, 9.9, Appendix 3, Appendix 4, Appendix 6, Appendix 10

cargo temperature

1.2, 1.3, 1.6.2, 1.6.3, 4.3 .2, 5.3, 5.10, 6 43, 6.8.3, 6.8.4, Appendix 5

cargo unloading - discharge

1.2.7, 1.4.3, 1.8.1 , 4.3.1 , 4.3.2, 4.5, 6.4.5, 6.7.9, 6.7.1 9, 6.7.20, 6.7.21, 7.4.7, 8.7, 10.5.4, Appendix 3, Appendix 4, Appendix 5

cargo vapour

1.6.2, 2.6.1 , 2.7.1 , 2.8.3, 2.1 0.1, 2.14.3, 3.5, 3.1 1.1, 3.11.12, 4.3.3, 4.4.2, 5.3.4, 5.4.4, 5.9, 6.4.5, 6.7.6, 6.7.1 3, 6.7.15, 6.8.2, 6.8.4, 7.4.2, 7.4.5, 8.3.2, 8.4.2, 8.8, 8.10.1 , 9.6.1, 10.5.1, Appendix 1, Appendix 3, Appendix 4

cargo vapour detection equipment

1.8, 3.11 .6, 5.4.5, 9.8, Appendix 3, Appendix 4

cargo venting systems

1.6.6, 4.3.3, 4.4.2, 5.8, 5.1 2.3, 6.3.4, 6.3.5, 6.4, 6. 7 .6, 6.8.2, 7.4, Appendix 3, Appendix 4

Certificate of Fitness

Definitions, 4.3.2, 5.4.5, 6.3.3, 6.3.4, 6.3.5, 9.8, 10.3.1, 10.3.3

Charge accumulation

1.4.2

Charge relaxation

1.4

Charged mists

1.4

Checklist, Ship/Shore Safety

6.2, 6.5.3, 6.9.7, Appendix 3, Appe ndix 4

Chemical absorption detectors

Definitions, 5.4.5

Chemical burns

9.7

Chemical detector tubes

5.4.5

Chemical fires

10.1 , 10.3.1, 10.3.2, 10.3.6, 10.3.9, 10.4.2

Chemical reaction

1.6.1 , 1.6.2, 5.1 3.1, 8.7.2, 10.1, 10.4.1

Chemical resistant clothing

3.11

Clearing cargo hoses or shore pipelines

6.4.3, 6.5, 6.7.1 6, 6.7.17, 7.1, 7.2, Appendix 3, Appendix 4

Circuits

5.3.2, 5.1 5.2, 6.7.4, Appendix 4

265

Cofferdam

Definitions, 1.6.6, 5.5.2, 6.4.5, 7.1 , 9.1

Cold weather

2.7.3

Combustible gas detector

Definitions, 5.4.4, 9.5

Combustion

1.3.2, 4.4.3, 4.5, 5.4.4, 5.1 3.1, 5.13.2, 5.1 3.3, 5.13.8, 6.7.8, 7.1 , 7.4.1 , 9.2.3, 10.4.1

Communication and communications equipment

2.1 3, 6.5.2, 6.5.3, 6.7.9, 6.7.10, 6.9.3, 7.4.9, 9.4.1 , 9.9, 10.2.2, Appendix 2, Appendix 3, Appendix 4, Appendix 7

Compatibility

1.6.6, 1.8.1 , 5.1 4.2, 6.3.4, 6.4.3, 6.4.5, 6.7.12, 6.9.2, 7.4.1 , 8.7.2

Compatibility chart

1.6.6, 1.8.2, 6.3.4

Compounds

1.5, 1.6.2, 1.6.3, 5.4.5, 10.3.2

Compressed nitrogen

1.6.2, 5.1 3.3, 5.13.4, 6.7.1 6, 7.1, 7.2, 7.4, Appendix 4

Contaminants

3.11 .6, 3.11 .14, 5.3.3, 5.4.2, 5.4.5, 5.13.3, 6.7.6, 8.4.1 , 9.4.2, Appendix 7

Contaminated clothing

3.11 .2, 3.11.5

Contaminated wash water

8.4.1

Contamination

1.6.7, 2.1 0.1, 3.5, 3.11 .2, 3.11 .6, 3.11.8, 4.3.1 , 5.3.3, 5.4.4, 5.5.2, 6.7.6, 6.7.1 1, 6.8.1, 6.8.3, 8.3.4, 8.10.1 , 9.3, 9.5, 10.5.1, 10.8,Appendix 4

Contingency plans

2.8, 6.4.1 , 6.8.4, 6.9.1 , 10.1, 10.5.1

Corrosive substances and vapours

1.6.5, 1.7, 3 .1 1.3, 3.11 .4, 3 .11 . 7' 3.11.8, 3 .11.9, 6. 7.2, 6.7.1 6, 6.8.6, 8.3.2, 8.5.4, 8.10.1 , 9.7, 9.8, 10.7, Appendix4

Cooling (fire-fighting)

10.3.1, 10.3 .2, 10.3.3, 10.3.5, 10.3.7, 10.4.1, 10.4. 2

Craft alongside

8.8, 10.4.4

Customs documentation

6.9.2, Appendix 1

D

266

Dangerous gas emission

1.6

Data sheets (see MSDS)

Definitions, 1.8.1 , 1.8.2, 3.1 1.6, 6.3.2, 6.9.6, Appendix 1, Appendix 3, Appendix 4, Appendix 5

Deballasting

4.3.2, 6.7.1 5

Deck tanks

2.14.4, 5.2

TANKER SAFETY GUIDE (CHEMICALS)

Deck valve and pipeline leakage

10.5.2

Decomposition

1.6, 9.2 .1 , 9.2.3, Appendix 5

Decontamination

8.3.4, 10.5.1, 10.8

Decontamination showers

8.3.4

Detector tubes

5.4.5

Discharge of cargo

1.8.2, 2.11 , 4.1, 4.3.1, 4.3.2, 4.5, 5.8, 5.1 4.1, 6.3.5, 6.4, 6.5, 6.7, 7.4.3, 7.4.7, 10.5.4, Appendix 3, Appendix4

Discharge of slops

4.1, 4.3 .1 , 4.3 .2, 6.3.5, 6.4, 6.7.22, 8.3, 8.4.8, 8.7, Appendix 4

Disconnection of cargo hoses

1.5.5, 2.7.2, 3.11 .4, 3.11.5, 3.11 .7, 6.5.1, 6.7.2, 6.7.18, Appendix 4

Draining of tanks and pipelines

2.14.4, 6.7.17, 6.7.1 8, 6.7.18, 6.9.7, 6.9.8, 8.4.4, 8.4.5, 8.4.6, 8.1 0.1, 9.6, 9.7, Appendix 3, Appendix4

Drills (emergency)

3.10.7, 9.9.1, 9.9.3, 10.2.1

Drip trays

5.7, 6.4.3, 6.7.1 8, 8.7.2, Appendix 3, Appendix4

Dryers

5.3.3, 5.1 3.6, 5.13 .8

Drying cargo tanks

4.4.3, 5.1 2.1, 6.4.2, 6.7.8, 7.4.9

Dry powder

10.3.7

Duct keel

9.1

E Earthing, electrical

2.14.5, 2.1 6, 5.15.3, 6.7.4, 6.7.1 1, 8.4.7, Appendix 3, Appendix 4

Electrical equipment

2.6.2, 2.1 3.1, 2.13 .2, 2.13.4, 2.1 4, 2.15, 5.1 5, 8.10.1 , Appendix 1, Appendix 2, Appendix 3, Appendix 4, Appendix 7

Electrical maintenance and repairs

2.13.2, 2.1 4

Electrical storms

2.7.2, Appendix 4

Electrochemical analysers

5.4.3

Electrolytic

5.4.3

Electrostatic charge generation

1.4.3, 1.4.6, 5.11 .2, 6.4.2, 6. 7.3, 8..4.4, Appendix 4

Emergency decontamination showers

2.7.3, 8.3.4, 10.8

267

Emergency escape breathing apparatus

3.11 .15, 3.1 1.16, 3.1 1.1 7, 6.5.4, 7.3

Emergency first aid

1.8.2, 9.4.1 , 10.2.2, 10.7, 10.7.2, 10.7.4, 10.7.5, 10.8, Appendix 5

Emergency jettison of cargo

1.6.2, 6.8.4, 10.5.4

Emergency organisation

3.1 0.1, 10.2, 10.2.3

Emergency plans and procedures

1.8.1 , 9.4.1 , 9.4. 2, 9.9.3, 10.1, 10.2, 10.3, 10.4, 10.5, 10.7, 10.8, Appendix 1, Appendix 2, Appendix 5

Empty tanks

1.4. 5, 1.6.4, 1.6.6, 6.7.1 9, 7.4.4, 7.4,9, 8.4.6, 10.5.3

Enclosed spaces

Definitions, 1.2.6, 2.1 0, 2.1 4.4, 2.1 4.5, 2.15, 3.6, 3.7.1 , 3.11 .12, 3.1 1.14, 5.4, 6.4.5, 6.7.1, 6.7.5, 6.7.21, 7.2, 7.3, 8.1, 8.5.3, 8.10, 9.1 , 9.2, 9.3, 9.4, 9.5, 9.6, 9.7, 9.8, 9.9, 10.3.6, 10.5.3, Appendix 2, Appendix 7

Enclosed space entry

2.1 0.1, 3.6, 3.7.1, 5.4.5, 6.4.5, 6.7.1, 6.7.5, 6.7.2 1, 7.3, 8.1, 8.5.3, 8.10, 9.1 , 9.2, 9.3, 9.4, 9.5, 9.6, 10.5.3, Appendix 2, Appendix 3, Appendix 4, Appendix 7

Enclosed space entry permit

2.1 0.2, 6.7.2 1, 9.4.2, 9.6, 9.6.1 , 9.7, 9 .8, Appendix 2, Appendix 7

Engine room

2.7.1 , 2.1 4.1, 2.14.2, 6.8.3, 9.4. 2, 10.5.1, 10.5.4, Appendix 2

Entry into cargo tanks

5.4.1 , 5.4.5, 6.7.21, 7.2, 7.3, 7.4.4, 8.10.1 , 9.6

Environmental awareness

1.8.2, 3.2.1 , 3.3, 3.7, 3.7.1 , 3.1 0.1, 4.1, 4.3, 4.3.1, 4.3.2, 4.3.3, 4.4.1 , 6.3.2, 8.2, 10.2.4, 10.3.6, 10.5.1, Appendix 1, Appendix 5

Evaporation of cargo

1.2.4, 6.3.5, Appendix 5

Expansion of cargo

1.2.2, 1.6.2, 6.3.4

Explosion proof equipment

Definitions, 2.1 5, 5.15.2

Eye protection

1.5.2, 1.7.1 , 2.7.3, 3.1 1.6, 3.1 1. 7, 3.1 1.15, 8.3.4, 9.9.5, 10.7.5, 10.8, Appendix 4, Appendix 5

F

268

Fans, cargo tank

5.1 2.1, 5.12 .2, 8.10.1

Filling capacity of cargo tanks

4.5, 5.2, 5.3 .1 , 5.3.4, 5.3.5, 6.3.5, 9.5

Filling ratio

Definitions, 1.2.1 , 5.2, 6.3.4

Filters

3.11 .12, 3.1 1.14, 5.3.3, 5.4.4, 9.8

Filter type respirators

3.11 .12

TANKER SAFETY GUIDE (CHEMiCALSJ

Fire-fighting

1.8.2, 2.6.2, 2.1 6, 6.4.3, 6.5.4, 6.7.14, 8.3.4, 8.1 0.2, 9.4.1 , 10.3, 10.4, Appendix 3, Appendix 4, Appendix 5

Fi rewires, emergency towing-off pennants

2.3, Appendix 4

First aid

1.8.2, 9.4.1 , 10.2.2, 10.7, 10.7.2, 10.7.4, 10.7.5, 10.8, Appendix 5

Fixed tank washing machines

4.5, 5.1 1.1, 8.4, 8.5, 8.6, 8.7, 8.1 0

Flame arresters

Definitions, 1.6.2, 6.8.4

Flame proof equipment

Definitions, 2.1 5, 5.15.2, Appendix 5

Flame screens

Definitions, 6.4.5, 6.7.6, Appendix 4

Flammability

Definitions, 1.3, 4.5, 5.4.4, 5.1 3.2, 6.4.3, 8.3.2, 8.4.1, 8.5.3, Appendix 4, Appendix 5

Flammable atmosphere

1.3, 1.4.6, 1.7.1 , 6.7.4, 8.4.2, 8.4.4, 10.3.5

Flammable cleaning solvents

2.14.5, 8.5.3, 8.5.4

Flammable range

Definitions, 1.3.2

Flammable vapour

Definitions, 1.3.1 , 1.3.2, 1.6.2, 2. 7.2, 2. 7.4, 2.8.3, 2.10.1, 2.1 3.4, 2.14.4, 5.4.4, 5.1 3.2, 7.4.1 , 7.4.5, 8.5.2, 8.7.2, 8.1 0.1, 9.5, Appendix 2, Appendix4

Flash point

Definitions, 1.3.1 , 1.3.2, 6.4.2, 7.4.2, 8.4.2, 8.4.4, Appendix 5

Flexible hoses

6. 7 .2, 10. 5.4, Appendix 9

Float gauges

5.3 .4

Foam for fire extinguishing

10.3.3, 10.3.4, 10.3.7, 10.4.3

Foam monitors

10.3.4

Foot protection

3.11.9

Free falling of liquids

1.4.3, 1.4.4, 6.3.5, 6.7.3

Freezing/freezing point

1.2.3, 1.7.1 , 2.7.3, 6.3.5, 6.4.3, 6.4.5

Frostbite

7.3

funnel fire

2.8.1

G Gangways

2.4.1 , 7.2, Appendix 4

Gas dangerous area

2.1 3.2

Gas detection equipment

Definitions, 5.4.1 , 5.4. 2, 5.4.3, 5.4.5, 9.8, Appendix 3, Appendix4

Gas emission due to chemical reaction

1.6

Gas freeing

Definitions, 1.4.3, 2.6.1 , 2.7.1, 2.8.1, 2.14.4, 2.14.5,

2.1 6, 2.1 7, 3.5, 3.1 1.4, 4. 5, 5 12, 5.12.1, 5.12.2, 5.1 2.3, 7.3, 7.4.1 , 7.4.8, 7.4.9, 8.1 , 8.3, 8.4, 8.5.5, 8.5.7, 8.8, 8.9, 8.10, 9.7, 10.4.4, Appendix 1, Appendix 2, Appendix 3, Appendix 4 Gas indicators

5.4.1 , Appendix 2, Appendix 4

Gas safe area

5.1 3.6, 5.13 .7

Gaskets

5.14.5, 6.7.2

Gauging

1.4.3, 5.3.1 , 5.3.4, 5.3.5, 6.7.3, 6.7.11, 6.7.13, 6.7.1 9, 6.8.3, 7.4.7, 8.4.4, 8.6.1 , Appendix 4

Generation of pressure surge

2.9.2

Grit blasting

2 .1 6, Appendix 2

H

VO

Halon

10.3.6

Hand protection

3 .11 .8, 10. 7.5, Appendix 5

Hand tools

2.1 7, 8.4.4

Hard arms

6.7.2, Appendix 4

Hazardous areas

2.1 3.3, 2.15, 2.16, 3.1 1.13, 5.1 5, Appendix 1, Appendix4

Hazards and properties of chemicals

1.1 , 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8

Health data

6.4.2

Heat production during chemical reaction

1.2, 1.6, 1.7 .1 , 6.8.4, 10.4.1, 10.4.2, 10.4.3

Heating coils

1.6.4, 3.7.1 , 5.1 0, 6.4.5, 6.7.21, 6.8.3, 8.1 0.2, 9.2.2, 9.7

Helicopter operation

2.1 2

TANKER SAFETY GUIDE (CHEMICALS)

High level alarms

4.4.2, 5.3.1 , 5.3.2, 5.3.5, 5.5.3, 5.1 6, 6.4.5, 6.6, 6.7.3, 6. 7 .1 0, Appendix 3, Appendix 4

High temperature

1.6.2, 1.6.3, 6.7.1 , 6.7.21, Appendix 2

High voltage

1.4.4, 1.4.5, 6.7.4, 10.3.3, Appendix 10

Hoses

1.5.5, 3.11 .4, 3.11.5, 3.11.7, 5.5.5, 5.9, 5.1 1.2, 5.1 4, 5.1 4.1, 5.1 4.2, 5.1 4. 3, 5.1 4.4, 5.14.5, 5.1 5.3, 6.4.2, 6.5.1 , 6.5.4, 6.7.2, 6.7.4, 6.7.1 0, 6.7.18, 6.9.7, 6.9.8, 7.2, 8.3 .2, 8.4.4, 8.4.6, 10.5.4, Appendix 1, Appendix 3, Appendix 4, Appendix 9

Hose manifold connection

5.1 4.5, 6.5.4, 6.7.2

Hose marking

5.1 4.2

Hose storage and maintenance

5.1 4.3

Hose testing

5.1 4.2

Hot work

Definitions, 2.1 3.2, 2.1 4, 2.16, 9. 7, Appendix 2

Hot work permit

Definitions, 2.1 3.2, 2.1 4, 9.7, Appendix 2

Hull corrosion by acids

1.6.5, 1.7.1 , 1.7.2, 10.5.3

Hull stresses

6.3.4, 6.9.6

Hydrogen

1.6.3, 1.7.1 , 5.4.3, 5.4. 5, 5.1 3.7, 9.2.1, 9.5, 9.7, Appendix 7

Ignition source

1.3.1 , 1.3.2, 1.4.6, 2.6.2, 2.8.1 , 2.1 3.4, 5.15.1 , 8.4.2, 8.4.4, 8.4.6, 9.8, 10.3.5, 10.3 .7, 10.4, Appendix 3, Appendix 4, Appendix 5

IMOCodes

4.1, 4.2, 4.3, 4.4, 4.5, 4.6

lncendive sparks

Definitions, 2 .1 3.1, 6. 7.4

Incompatible chemicals

1.6.1 , 1.6.6, 1.6.7, 1.8. 2, 2.1 0.1, 6.3.4, 6.4.5, 6.7.18, 8. 7 .2, 10. 5.3, Appendix 5

Inert gas

Definitions, 1.6.2, 1.6.3, 2.1 4.4, 2.16, 3.11 .1, 4.4.3, 4.5, 5.3 .4, 5.3.6, 5.4.3, 5.4.4, 5.9, 5.1 2.1, 5.13, 6.4.2, 6.4.3, 6.4.5, 6.6, 6.7.7, 6.7.8, 6.7.1 6, 6.7.20, 6.8.1 , 6.8.5, 7.1 , 7.4, 8.1, 8.4, 9.2, 9.3, 9.6.1, 9.7, 9.9.6, 10.3.8, Appendix 3, Appendix 4

Inert gas and inhibited chemicals

1.6.2, 6.7.8, 6.7.1 6, 6.8.4

Inert gas hazards and precautions

7.2, 7.3

271

Inert gas over pressure

5.1 3.4, 6. 7.8, 6. 7.20, 6.8.5, 7.4.4, 7.4. 5, 7.4.6, 7.4.9, 8.4.5

lnerting of tanks

7.4.3, 7.4.4

Infra-red cargo vapour detectors

5.4.4, 5.4.5

Inhibited cargo certificate

1.6.2, 1.8.3, 6.3.5, 6.7.8, 6. 7.1 2, 6.8.4, Appendix 4, Appendix 6

Inhibitor

Definitions, 1.4.3, 1.6.2, 1.8.2, 1.8.3, 6.3.5, 6.4.3, 6.5.1, 6.7.8, 6.7.1 2, 6.8.4, 6.9.6, Appendix 3, Appendix 4, Appendix 5, Appendix 6

Injury to personnel

1.5.1 , 3.8.1 , 3.1 1.7, 3.1 1.8, 3.1 1.9, 6.7.16, 9.4.1 , 9.9.4, 9.9.5, Appendix 4

Instrumentation

5.3, 5.4, 6.4.5, 9.5, Appendix 3, Appendix 5

Insulating flange

Definitions, 5.1 4.5, 6. 7.4, Appendix 4

Intrinsically safe equipment

Definitions, 5.1 5.1, 5.15.2

Isolation of cargo tanks and piping systems

2.8.3, 2.1 4.4, 6.4.5, 6.7.10, 7.2, 8.3.4, 8.1 0.2, 9.7, Appendix 3, Appendix 4, Appendix 7

J Jettison of cargo

10.5.4

L

2n

leakage of air. inert gas or cargo vapours

2.1 0.1

leakage of cargo liquid

2.1 0.1, 5.7, 6.4.5, 6.7.5, 6.8.1, 10.5.2, 10.5.3,

lifeline

9.9.5, Appendix 7

lighting (of gangway and cargo area)

2.4.2, 2.1 3.2, 6.4.5, 6.7.21, 9.7, 9.9.4, 9.9.5

liquid level gauges

5.3.4, 6.7.1 1

liquid nitrogen

5.1 3.3, 5.13.5, 7.3

liquid/vapour thermometers

5.3.7

loading arms

3 .11 .4, 6.4.2, 6.5.1, 6. 7 .2, Appendix 1, Appendix 4

loading of cargo

6.7

loading plan

2.9.2

loading rate

2.9.2, 6.5.1, 6.5.4, 6.7.3, 6.7.6, 6.7.7, 6.7.10, Appendix4

TANKER SAFETY GUIDE (CHEMICALS)

low pressure alann

6.7.6, 6.8.5

low temperature hazard

7.3

low temperature hazard

7.3

M Machinery space

2.8, 4.3 .1 , 6.4.5, 7.2, 7.3, 8.4.3, 8.10.1, Appendix 3, Appendix 4, Appendix 10

Maintenance of an inert atmosphere

7.4.2

Management of slop tanks

8.7.2

Manual sweeping of cargo tanks

6.7.21, 9.7

Materials of construction

5.3 .6

Mechanically powered tools, use of

2.16, Appendix 2

Medical advice

10.7.1, 10.7.2, 10.8

Membrane separation nitrogen generators

5.13.7

Metal cargo arms

Appendix 4

MFAG tables

10.7.2, 10.8

Mobile telephones

2.13.3, Appendix 1, Appendix 3, Appendix 4

Moorings

2.2, 6.6. 6.7.2, Appendix, Appendix 4

MSDS

Definitions, 1.8.1 , 1.8.2, 3.1 1.6, 3.11 . 7, 3.1 1.8, 6.3.2, 6.4.4, 6.7.1 1, 6.9.6, 8.3.2, 8.5.3, 8.5.4, 10.4.3, 10.7, 10.7.5, 10.8, Appendix 1, Appendix 3, Appendix4, Appendix 5

Multi-gas detector

5.4.5, 9.2, 9.4.2, 9.5, 9.7

N Naked lights

2.5.1 , 2.5.2, 10.5.1,Appendix 4

Navigation

6.9.4, 6.9.8, 10.2.2

Nitrogen

1.6.2, 1.6.3, 3.11 .1, 4.4.3, 4.5, 5.4.3, 5.7, 5.13, 6.3.5, 6.4.3, 6.5.1 , 6.5.4, 6.7.7, 6.7.8, 6.7.1 6, 6.7.20, 6.8.5, 7.1, 7.2, 7.3, 7.4, 8.4.2, 9.2, 9.2.1, 9.2.3, 9.2 .4, 9.6.1 , Appendix 3, Appendix 4

Nitrogen flow rate

5.13.6, 6.7.8, 7.4.9, Appendix 4

273

Nitrogen generators

5.1 3.3, 5.13.6, 5.13.7, 7.1, 7.4.1

Notification of spillage into the sea

10.6

0 Oil fired inert gas generators

5.1 3.3, 5.13.8

Opening up of cargo lines and handling equipment

8.1 0.2

Operational discharges

1.8.2, 4.1 , 4.3.1 , 4.3.2, 4.6, 6.4.2, 6.5.4, 6.7.1 5, 6.7.22, 6.9.7, 8.3.2, 8.3.4, 8.5.4, 8.7.3, Appendix 3, Appendix4

Overfill detection systems

5.3.5

Over pressure

1.2.3, 1.6.3, 5.3.1 , 5.9, 5.1 3.4, 6.3.5, 6.7.8, 6.7.20, 6.8.4, 6.8.5, 7.4.4, 7.4.5, 7.4.6, 7.4.9, 8.4.5

Over pressurisation

1.2.3, 1.6.3, 5.3.1 , 5.9, 5.1 3.4, 6.3.5, 6.7.8, 6.7.20, 6.8.4, 6.8.5, 7.4.4, 7.4.5, 7.4.6, 7.4.9, 8.4.5

Oxygen analysers

5.4.1 , 5.4.3, 5.4.5, Appendix 3, Appendix 4

Oxygen compounds, peroxides

1.6.1 , 1.6.3

Oxygen content of tank atmospheres

7.4

Oxygen deficiency alarms

5.4.3, 7.3, 9.2, 9.2.1

Oxygen level

Definitions, 5.4.3, 5.4.5, 5.1 3.2, 6.7.8, 6.7.21, 6.8.5, 7.3, 7.4, 8.4.5, 9.2, 9.2.4, 9.4.2, 9.5, 10.4.1

p

274

Padding

Definitions, 4.4.3, 6.5.1 , 6.7.8, 6.8.5, 7.4.1

Paramagnetic oxygen sensors

5.4.3, 5.4.5

Peroxides

1.6.1 , 1.6.3

Personal Protective Equipment (PPE)

1.5.2, 1.5.5, 1.8.2, 3.6, 3.1 1, 4.4.2, 5.3.4, 6.3.5, 6.4.3, 6.4.4, 6.6, 6.7.2, 6.7.1 1, 6.7.13, 6.7.1 6, 6.7.21, 7.3, 8.3.2, 8.3.4, 8.4.3, 8.5.3, 8.5.4, 8.1 0.2, 9.4.2, 9.7, 9.8, 9.9.5, 10.3.9, 10.8, Appendix 1, Appendix 2, Appendix 3, Appendix 4, Appendix 5, Appendix 1O

Physical properties of chemicals

1.2

Pigging

6.7.1 6, Appendix 4

TANKER SAFETY GUIDE (CHEMICALS)

Pipelines

1.4.1 , 1.4.3, 1.4.4, 1.6.2, 1.6.4, 2.9.1 , 2.9.2, 2.1 4.4, 2.14.7, 2.1 5, 2.16, 4.3.2, 4.4. 2, 5.3.6, 5.6, 5.7, 5.9, 6.4.3, 6.4.5, 6.7.2, 6.7.3, 6.7.1 6, 6.7.18, 7.4.9, 8.4.8, 8.10.1, 8.1 0.2, 9.7, 10.5.2, Appendix 2, Appendix 3, Appendix 4, Appendix 7

Planning for emergencies

6.9.1 , 10.1 , 10.2, 10.3, 10.4, 10.5, 10.7

Poisoning

1.5, 3.11 .1 2

Pollution prevention

3.2 .1 , 4.1 , 4.3

Polymerisation

Definitions, 1.6, 5.3.5, 6.4.5, 6.7.1 2, 6.8.4, 8.5.2, Appendix 5

Portable electrical equipment

2.13.4, Appendix 1, Appendix 3, Appendix 4

Portable tank washing machines and hoses

5.1 1.2

Potential for static electricity

1.4, 6.4.2, 6.7.3, 8.4.4, 8.4.6, 10.3.5, Appendix 4

Pour point

Appendix 5

Preparation for cargo operations

6.4

Pressure in a f luid

5.3 .6

Pressure in a tank

4.4.1 , 4.4.2, 4.4.3, 5.3.4, 5.3.6, 6. 7.9, 6. 7.1 6, Appendix 3, Appendix 4

Pressure (liquid level) gauges

5.3 .4, 6.6, 6.7.11

Pressure (vapour) gauges

4.4.2, 5.3

Pressure loss

6.8.5

Pressure surge

2.9, 6.8.3, Appendix 4

Prewash

6.3.5, 6.4.2, 6.4.3, 6.7.22, 8.2, 8.4.6, 8.7.3

Procedures and Arrangements (P&A) Manual

4.3 .2, 6.7.22, 8.2, 8.4.1 , 8.4.6, 8.5.4, 8.7.1 , 8.7.3, 8.1 0.1

Puddling, sweeping or squeegeeing

6.7.21, 9.7

Pumprooms

2.7.1 , 2.1 0.1, 3.11.4, 4.4.2, 5.5.1 , 5.5.3, 5.1 6, 6.4.5, 6.7.5, 6.8.1 , 9.1 , 10.5.3, Appendix 4

Pumps, cargo (cargo pumps) Purging

Definitions, 1.3.2, 1.6.4, 7.1 , 7.4.1 , 9.2.3, 9.4.2, Appendix 3, Appendix 4

Putrefaction

1.6.3

275

R Radar gauges

5.3.4

Radio

2.1 3, 6.5.2, 6.6, 6.9.7, 9.9.5, 10.5.4, 10.7.2, Appendix 1, Appendix 3, Appendix 4

Raising the alarm

9.9.4, 10.8

Reaction between chemicals

1.6, 1.7.1 , 8.5.2, 8.7.2, 10.1, 10.4.1 , 10.4.2, 10.4.3

Reactive chemicals, with air or oxygen

1.6, 6.8.6, 9.2.4

Reactive chemicals, with water

1.6, 6.7.8, 6.8.6, 8.4.1 , 8.5.2, Appendix 4

Reactivity

1.6, 1.8.2, 8.3.2, Appendix 5

Readiness to move

2.11

Receiving nitrogen from shore

7.4.9, Appendix 3, Appendix 4

Recirculated wash water

8.4.1 , 8.4.6

Reducers

6.5.4, 6.7.2

Removal of sludge, scale and sediment

2.14.4, 9.5, 4.3.1

Rescue equipment

9.4.1 , 9.4.2, 9.6.1 , 9.8, 9.9, Appendix 7

Rescue from enclosed spaces

9.2, 9.6.1 , 9.8, 9.9, Appendix 7

Rescue plan

9.2, 9.4, 9.8, 9.9, 10.7.2

Respiratory protection

3.11 .6, 3.11 .11 , 3.1 1.12, 3.1 1.15, 9.8, 10.7.5, Appendix 5

Responsibility for cargo operations

3 10.5, 6.2, 6.9.2

Resuscitation equipment

9.9.3, 9.9.4, 9.9.5, Appendix 7

s

276

Safe area

2.1 3.3, 5.13 .6, 5.13.7

Sample cans

1.4.6

Sampling

1.4.3, 1.5.5, 1.6. 7, 3.1 1.1, 3.1 1.4, 3.1 1.5, 4.3.1, 5.4.2, 5.4.3, 5.4.4, 5.4. 5, 5.7, 6.4. 2, 6.4. 3, 6.4. 5, 6.7.1, 6.7.1 1, 6. 7.12, 6.7.1 3, 6.7.1 4, 7.4.7, 8.4.4, Appendix 4, Appendix 7, Appendix 1O

Satellite communication equipment

2 .1 3, Appendix 4

Scrubber and condensate water

5.1 3.8

TANKER SAFETY GUIDE (CHEMICALS)

Sea valves, suction and discharge

6.5.4, 10.5.4, Appendix 3, Appendix 4

Segregation of cargoes

1.6.4, 1.6.6, 4.4.2, 5.1 , 6.4.5

Self-reaction, self/spontaneous polymerisation

1.6.2, 5.3.6, 6.4.5, 6.7.1 2, 6.8.4, 8.5.2, Appendix 5

Ship/shore bonding cables

5.15.3, 6.7.4

Ship/shore checks before cargo operations

6.5

Ship/Shore Safety Checklist

6.5.3, 6.9.7, Appendix 3, Appendix 4

Ship/shore transfer

6.5, 6.6, 6.7

Ship to ship transfer

6.9

Ship to Ship Transfer Guide

6.9.1 , 6.9.2, 6.9.6, 6.9.7

Ship's cargo hoses

5.14

Shore pipelines

6.7.1 6

Shutdown circuits

5.3 .2, 5.3.6

Shutdown procedures

5.3 .2, 5.3.6, 6.7.1 0, 6.9.6, Appendix 3, Appendix 4

Slops

4.3 .1 , 6.3.5, 6.4.2, 6.7.22, 8.3.2, 8.3.4, 8.4.8, 8.7

Slop tanks

1.6.3, 2.1 0.1, 4.3.1, 6.4.3, 6. 7 .18, 8.4.8, 8.7.1 , 8.7.2, 10.5.1

Sloshing

Definitions, 1.2.1 , 5.2, 5.3.4

Sludge removal

2.14.4, 4.3.1

Solubility

1.2.8, Appendix 5

Solvents

1.2.8, 2.14.5, 3.11 .8, 8.5.3, 8.5.4, Appendix 5

Sounding pipe

8.4.7, 8.6.1

Sounding rod

8.4.4, 8.4.7

Sources of ignition

2.6.2, 2.8.1 , 8.4.2, 8.4.6, 10.4.2

Span gas

Definitions, 5.4.2

Special cleaning methods

8.5

Specific gravity

Definitions, 1.2.1 , 4.3.1 , 5.2, 5.3.7, 6.3.4, 6.4.2

Spillage of cargo

2.7, 2.9, 3.11.4, 4.4.2, 6.4.3, 6.9.6, 10.6, 10.5.1 , 10.5.2, 10.5.3, 10.6, Appendix 3, Appendix 4

Splash filling

1.4.4, 6.7.3

Spool pieces

4.4.2, 5.1 3.8, 6.7.2

277

Stabilisers, of chemicals

1.6.2

Stability of a ship

4.4.4, 4.6, 6.3.4, 6.3.5, 6.4.3, 6.7.15, 6.8.6, 6.9.6, 10.5.4

Static accumulator cargoes

1.4, 6.7.3, 6.7.1 1, 6.7.16, 8.5.6

Static electricity

Definitions, 1.4, 3.1 1.12, 5.3.6, 5.1 1.2, 6.3.5, 6.4.2, 6.4.3, 6.7.3, 6.7.1 1, 8.4.4, 8.4.6, 8.5.6, 10.3.5, Appendix4

Steam in cargo tanks

1.4.3, 1.4.5, 1.6.4, 5.1 0, 5.12.2, 8.4.6, 8.5.5

Stresses in ship structure

6.7.1 s. 6.9.6

Stripping

4.3.2, 5.5.2, 5.7, 6.3.5, 6.7.1 8, 6.7.22, 7.1 , 8.4.6

Surge pressure

2.9, 6.8.3, Appendix 4

Sweeping of cargoes

6.7.21, 9.7

T

278

Tank atmosphere

1.6.2, 1.6.3, 2.1 4.4, 3.11 .1 , 4.5, 5.3.2, 5.4, 5.1 3.1, 6.3.5, 6.7.8, 6.7.20, 6.7.21, 6.8.4, 6.8 .5, 7.1 , 7.4.1 , 7.4.2, 7.4.4, 7.4. 7, 7.4.9, 8.4, 8.5.3, 8 .5.5, 8.5.6, 8.1 0.1, 9.2, 9.3, 9.4, 9.5, 9.6, 9.8, 9.9, Appendix 3, Appendix 4

Tank atmospheres and cargo quality

4.4.3, 5.1 3, 6.3.5, 7.1, 7.4.1, 7.4.2, 9.2.3

Tank capacity limitations

4.5, 5.2, 5.3 .1 , 5.3.4, 5.3.5, 6.3.5, 6.7 .1 0

Tank cleaning and washing

1.2.6, 1.4.3, 1.4.5, 1.6.4, 1.6.5, 1.8.2, 2.6.1, 2.8.1, 2.16, 2.1 7, 3.1 0.5, 3.11 .5, 4. 3.1, 4.3.2, 5.2, 5.3.4, 5.4.2, 5.11, 6.2.1 , 6.4.2, 6.7.8, 7.2, 7.4.8, 7.4.9, 8 .3, 8.4, 8.5, 8.6, 8.7, 8.8, 8.9

Tank cleaning equipment

5.11 , 8.5.3, 8.9

Tank cleaning plan

8.3, 8.5.2, 9.4

Tank drying

4.4.3, 5.1 2.1, 6.4.2, 6. 7 .8

Tank inspection

6.4.2, 6.7.1 , 6.7.1 1, 7.2, 7.3

Tank leakage

6.7.3, 6.7.1 9, 6.8.1, 6.8.5, 6.9.7, 9.3, 9.6.1, 10.5.3

Tank overflow control

4.4.2, 5.3.5, 6.7.3

Tank pressure

1.6.2, 4.5, 5.3.6, 5.9, 5.1 3.4, 6. 7.6, 6. 7 .7, 6. 7 .9, 6.7 .16, 7.4.9, 8.4.5, Appendix 4

Tank strength

1.2.1 , 5.2

Tank venting systems

1.6.6, 4.4.2, 5.8, 6.3.4, 6.3.5, 6.4.2, 6.4.3, 6.4.5, 6.7.6, 6.7.8, 6.8.2, 7.4.5, 7.4.9, Appendix 3, Appendix 4

TANKER SAFETY GUIDE (CHEMICALS)

Tanker operations at general cargo berths

2.6.2

Tankers at adjacent berths

2.6.1

Tape (liquid level) gauge systems

5.3 .4

Temperature log

6.8.3

Temperature monitoring equipment

5.3 .1 , 5.3.7, 6.8.3

Temperature of cargo

1.2, 1.3, 1.6, 3.11 .6, 4.3.2, 5.3, 5.1 0, 5.14.1 , 5.1 5.1, 6.4.2, 6.4.3, 6.8.3, 6.8.4

Terminal's cargo hoses

6.7.2

Testing enclosed spaces atmospheres

9.2, 9.3, 9.5, 9.9.3, 9.9.4, Appendix 7

Thermal conductivity meters

5.4.4

Thermal stresses

1.2.3

Thermometers

5.3 .7

Threshold Limit Values (TLV) for toxic exposure

Definitions, 1.5.4, 1.8.2, 8.1 0.1, 9.5, Appendix 5

Topping off cargo tanks

2.9.2, 6.7.1 0, 6.9.6, Appendix 4

Towing-off pennants, firewires

2.3, Appendix 4

Toxic cargoes

1.5.5, 2.6.2, 4.4.2, 6.3.5, 6.4.5, 6. 7.2, 6. 7.1 3, 8.4.2, 10.7.2, 10.7.3

Toxic vapour detection

1.8.2, 5.4.5, 9.8, Appendix 3

Toxic vapours and gases

1.5, 2.8.3, 2.10.1, 2.1 0.2, 3.11 .1 1, 3.11 .1 2, 3.11 .1 3, 4.4.2, 5.4.5, 8.4.2, 8.4.3, 8.1 0.1, 8.10.2, 10.3.9, 10.4.3, 10.5.4, Appendix 4

Toxicity

1.5, 1.8.1 , 6.4.3, 6.5.4, 8.3.2, 8.5.3, Appendix 5

Training

3.2 .1 , 3.4, 3.10, 3.1 1.16, 3.1 1.17, 6.1 , 7.3, 9.4.1 , 9.8, 9.9.3, 10.1

Toxic vapours and gases

1.5.2, 2.8.3, 2.1 0.1, 2.10.2, 3.11 .11, 3.11 .1 3, 4.4.2, 5.4.5, 8.4.2, 8.4.3, 8.1 0.1, 8.10.2, 10.3.9, 10.4.3, 10.5.4, Appendix 4

Toxicity

1.5.1 , 1.5.2, 1.5.3, 1.8.1, 6.4.3, 6.5.4, 8.3.2, 8.5.3, Appendix 5

Training

1.1, 3.10, 3.1 0.1, 3.10.2, 3.1 0.3, 3.10.4, 3.1 0.5, 3.11.16, 3.11 .1 7, 10.1

Turbulence in inert gas

7.4.4, 7.4.9

Turbulence in liquid causing static electricity

6.7.3

2"79

u Ultrasonic liquid level gauges

5.3.4, 5.3.5

Unearthed electrical conductors

1.4.6, 2.1 3.1

Unstable chemicals

1.6.2

v Vacuum

1.2.3, 5.8, 5.9, 5.13.5

Valve glands

2.1 0.1, 4.4.2, 6.7.5

Valves:

280

- Automatic emergency shutdown valves

2.9.1 , 2.9.2, 6.4.2, Appendix 4

- Cargo system valves

2.9.1 , 2.9.2, 2.1 4.4, 4.3.1, 4.4.2, 5.6, 6.3.4, 6.4.3, 6.4.5, 6.5.1 , 6.5.4, 6.6, 6.7.5, 6.7.1 0, 6.7.17, 8.1 0.1, 9.6, 9.7, 10.4.4, 10.5.1 , 10.5.2

- High velocity vent valves

8.1 0.1

- Isolating valves

5.7, 5.13.8

- Manifold valves

5.7, 6.7.2, 6.7.8, 6.7.9, 6.7.1 0, 6.7.16, 6.7.1 7, 6.7.18, 6.7.22, 7.4.9

- Non-return valves

5.1 3.8, Appendix 3, Appendix 4

- Pressure/vacuum (PV)

1.2.5, 2.7.3, 5.8, 5.9, 6.4.5, 6.7.6, 6.7.7, 6.7.8, 6.7.9, 6. 7 .16, 6.8.2, 6.8.5, 7.4.4, 7.4.9, Appendix 3, Appendix 4

- Pressure relief valves

5.1 3.4

- Sea valves

6.5.4, 10.5.4, Appendix 3, Appendix 4

Vapour concentration

1.2.6, 1.3.1 , 1.3.2, 1.5.4, 2.6.1 , 2.1 0.1, 2.16, 2.1 7, 3.11 .6, 4.4.2, 5.4.4, 5.4.5, 5.13.2, 7.4.1 , 8.1 0.1, 9.5, 10.3.2

Vapour density

Definitions, 1.2.6, 1.3.2, Appendix 5

Vapour detection equipment

1.8, 3.11.6, 5.4.5, 9.8, Appendix 3, Appendix 4

Vapour pressure

Definitions, 1.2.4, 1.2.5, 1.3.1, 2.9.2, 5.10, 6.3.5, Appendix 5

Vapour return lines and connections

5.9, 6.4.5, 6.5.1 , 6.7.7, 6.7.8, 7.4.4, 8 .3.4, 9.2.2

Ventilation of cargo residues

6.7.21, 9.5

TANKER SAFETY GUIDE (CHEMiCALSJ

Ventilation of spaces

2.5.1 , 2.7.4, 2.8.3, 2.1 0.1, 2.14.4, 4.4.2, 6.5.4, 6.7.21, 8.4.1 , 8.4.3, 8.1 0.1, 9.1, 9.4.2, 9.5, 9.7, 9.9.4, 9.9.5, 10.5.1, Appendix 3, Appendix4, Appendix 7

Ventilation of cargo tanks

2.8.3, 4.4.3, 8.1 0.1, 8.4.1, 8.4.3, 8.10.1

Ventilation systems

Definitions, 2.7.4, 2.8.3, 2.1 0.1, 2.14.4, 4.4.2, 5.5.3, 5.16, 6.5.4, 8.1 0.1

Venting systems

1.6.6, 4.4.2, 5.8, 6.3.4, 6.3.5, 6.4.2, 6.4.5, 6.7.6, 6.7.8, 6.8.2, 7.4.5, Appendix 3, Appendix 4

Viscosity

1.2.7, 1.8.2, 4.3.2, 6.3.5, 6.4.2, 6.4.3, 8.7.3, Appendix 5

w Warning notices

2.5

Washing (cleaning) tanks

1.4.5, 4.3, 4.3 .1 , 4.3.2, 5.11 , 6.3.5, 6.4.2, 8.3.2, 8.4, 8.5, 8.6

Wash water

8.4.1 , 8.4.4, 8.4.5, 8.4.6, 8.4.8, 8. 7.1 , 8. 7.3

Weather conditions

1.6.2, 2.7, 3.11.1, 4.6, 5.2, 6.4.5, 6.5.4, 6.8.2, 6.8.3, 6.8.6, 6.9.5, 7.3, 7.4.5, 10.5.3

Welding

Definitions, 2.1 4.1, 2.14.5, Appendix 2, Appendix 1O

Wind conditions

2.7.1, 3.11 .1, 7.3, 8.10.1, 10.5.1 , Appendix 3, Appendix 4

Work in enclosed spaces

9.7

Work permit

2.13.2, 2.1 4, 2.15, 2.1 7, 9.7, Appendix 2

281

282

TANKER SAFETY GUIDE (CHEMiCAL5)

VISITOR INFORMATION CARD

PURPOSE It is essential that all persons, including contractors and sub-contractors boarding the ship, are provided with an overview of the hazards present and the safety precautions to observe while they are on board. It is also recommended that similar advice is provided to those persons who are working close to the vessel, for example, the crews of barges (bunkers, stores) and to personnel working close to the ship's side. This is especially relevant if cargo operations or gas freeing operations are taking place which can spread cargo vapours over a large area. The Visitor Information Card is intended as an example to demonstrate what information should be provided to visitors. Information cards should be designed taking into account the plans, procedures, operations and specifics of the company and vessel. Information cards should always be assessed and modified for each port arrival, taking into account operations, cargoes, anticipated visitors and any other special arrangements.

VISITOR INFORMATION CARD

HEALTH •

All required vaccinations should be current; and

•

You must advise the ship's Master of any allergies or medication that you are taking.

BEFORE BOARDING A VESSEL •

You must not board the vessel under the influence of alcohol or drugs;

•

You must have authority to board the vessel from all relevant shore authorities e.g. Immigration, Port Authority, Customs or Terminal Operators;

•

Cigarette lighters or matches are not allowed;

•

You must follow instructions provided by the Master or a representative; and

•

You must advise the Master or a representative of the reason for and objectives of your visit.

DURING YOUR VISIT •

You must participate in a safety briefing provided by the Master or the designated representative;

•

You must wear PPE as required by the Master or the designated representative;

• •

You must be familiar with the ship's emergency alarms and procedures; You must inform the Master or representative when you intend to leave the vessel; and

•

You must follow instructions from the crew and if in any doubt ask.

EMERGENCY PROCEDURES The ship·s emergency alarms, signals and procedures will be clearly described for visitors.

HAZARDOUS AREAS Areas where flammable gas may be present are typically designated as 'Gas Dangerous Zones/Spaces'. In any of these areas the following are NOT PERMITTED:

•

Cameras;

•

Mobile phones; Torches;

• •

MUSIC players;

•

Electronic key fobs;

•

Portable radio equipment; or

•

Tablet or laptop computers .

Any portable electrical equipment that might be taken into a hazardous area must be of a safe certified type. Such equipment shall be inspected by a competent person on board the vessel prior to its use.

TANKER SAFETYGUIDE (CHfMlCALS)

REPORTING AND SECURITY PROCEDURES The International Ship and Port Facility Security (ISPS) Code applies on board this vessel: •

You must obtain a visitor or contractor pass;

•

You must not enter restricted areas unless authorised; You must allow baggage and equipment to be inspected, as required;

•

You must provide photo identification and sign the visitors' book; and

•

You must deposit portable electronic equipment wrth the Master or a representative if requested.

SAFE MOVEMENT AROUND THE VESSEL Where required you should be accompanied by a member of the ship's crew: •

You must not interfere with the operational activities of the vessel;

• •

Manifold areas are restriaed when loading arms or hoses are connected; and Particular care should be taken in the vicinity of mooring ropes, wires and winches.

PERSONAL PROTECTIVE EQUIPMENT (PPE) The following minimum protective equipment must be worn by visitors before accessing operational areas:

CARGO Information regarding the cargoes being carried on board including Material Safety Data Sheets (MSDS) and further information can be found at

COMPANY SAFETY AND ENVIRONMENTAL PROTECTION POLICY N.B. Information should be provided on the company's Safety and Environmental Protection Policy.

HOT WORK PERMIT

This permit relates to any hot work involving temperature conditions which are likely to be of sufficient intensity to cause ignition of combustible gases. vapour or liquids m or adjacent to the area involved. Before completing this form, the guidance notes below and in Section 2 14 of the ICS Tanker Safety Guide (Chemicals) should be referred to.

Guidance notes for hot work permit: Section 1 - Must be completed In all cases. Section 2 - Applies to worl: not involving naked flame or continuous spark production, which has a significant potential for producing sparks and includes the use of electrical equipment, mechanically powered tools, use of air·driven rotary equipment, sand or grit blasting, hammering and chipping and movement of equipment or materials over or near to machinery that is operating. Section 3 - Applies to all hot work involving high t emperatures, open flame. electric arc or continuous source of sparks, etc. This type of work includes but is not ilmited to welding, burning and gnnding. Before initiating hot work, consider if an alternative work plan could avoid the need for hot work. Section 4 - Must be completed m all cases. Ail the following steps and precautions must be undertaken for each hot work task depending on the nature of the work.

TANrER SAFETY GUIDE (CHEMICALS)

SECTION 1 MV _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Permit No. _ _ _ _ _ _ _ _ __

This permit is valid* From _ _ _ _ _ _ _ _ _ _ _ _ _ _ (Time} _ _ _ _ _ _ _ _ _ (Date - DD/MMIYYYY) To _______________ (Time) _ _ _ _ _ _ _ _ _ (Date - DD/MM/YYYY)

•start and finish t imes must not ex(eed the authorised working hours Exact Location of Hot Work:

Has an enclosed space entry permit been issued?

YesO

Description of hot work (to include type of equipment to be used):

Personnel carrying out hot work:

Rank: _ _ _ _ Name _ _ _ _ _ _ _ _ _ _ _ _ _ Signature _ _ _ _ _ _ _ _ _ __ Rank: _ _ _ _ Name _ _ _ _ _ _ _ _ _ _ _ _ _ Signature _ _ _ _ _ _ _ _ _ __ Officer responsible for hot work:

Rank: _ _ _ _ Name _____________ Signature _ _ _ _ _ _ _ _ _ __ Officer responsible for safety:

Rank: _ _ _ _ Name _ _ _ _ _ _ _ _ _ _ _ _ _ Signature _ _ _ _ _ _ _ _ _ __

SECTION 2

I Yes I No I NI A 1

Has a planning meeting been held and a risk assessment completed?

2

Has the hot work are;1 been checked wrth a combustible gas indicator for the presence of flammable vapours?

3

Has the surrounding area been made safe?

Time

TANKER SAFfTY GUIDE(CHfMICALI)

SECTION 3 Time 1 Has a planning meeting been held and a risk assessment completed? 2 Has shore management agreement for this hot work been obtained ? 3 Has the hot worl( area been che
Spedal/addltlonal conditions or pre
TANrER SAFETY GUIDE (CHEMICALS)

SECTION 4 I vel'ify that the job area has been examined and authorise hot work to be carried out providing the above conditions are maintained throughout the term of the permit.

Master:

Mame ___________________ Signature _ _ _ _ _ _ _ _ _ __

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ (Time) _ _ _ _ _ _ _ _ _ _ (Date - DDIMMIYYYY)

Officer responsible for hot worlc: Rank: _ _ _ _ Name _ _ _ _ _ _ _ _ _ _ _ _ _ Signature _ _ _ _ _ _ _ _ _ __

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ (Time) _ _ _ _ _ _ _ _ _ _ (Date - DD/MM/YYYY)

The wori< has been completed and all persons under my superv1sion and all materials and equipment, have been wrthdrawn. Officer responsible for safety: Rank: _ _ _ _ Name _ _ _ _ _ _ _ _ _ _ _ _ _ Signature _ _ _ _ _ _ _ _ _ __

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ (Time) _ _ _ _ _ _ _ _ _ _ (Date - DD/MM/YYYY)

TANKER SAFfTY GUIDE (CHfMICALI)

SHIP/ SHORE SAFETY CHECKLIST

Ship ~

Name: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __

Berth; _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __

Port·-------------------------~ Date of Arrrval: _ _ _ _ _ (00/MMIYYYY) Time of Arrival: - - - - - - - Instruct ions for completion •

All questions should be answered affirmatively by clearly ticking (v') the appropriate box;

•

If an affirmative answer is not possible. the reason should be specified and agreement reached between ship and shore on appropriate alternative risk mitigation measures and precautions; and

•

'N/A' should be used for questions considered not applicable.

The presence of t he letters 'A', 'P', 'R'. or a combination of letters 1n the Code column indicates the following;

A p

R

Any referenced procedures and agreements should be in writing in the remarks column of t his Checklist or other mutually acceptable form

In the case of a negative answer the operation should not be earned out without permission of the port authonty

Items to be re-
1

Is there safe access betvveen ship and shore?

R

2

Is the ship securely moored'

R

3

Is the agreed ship/shore communication system operative?

4

5

6

AR

Are emergency towing-off pennants (firewires) correctly rigged and positioned (where applicable)?

R

Are the ship's fire hoses and firefighting equipment positioned and ready for immediate use?

R

Are the shore's fire hoses and firefighting equi pment positioned and ready for immediate use?

R

7

Are the ship's cargo and bunker hoses/arms, pipelines and manifolds in good condition. properly rigged and appropriate for the service intended?

8

Are the shore cargo and bunker hoses/arms, pipelines and manifolds in good condition. properly rigged and appropriate for the service intended?

System: Backup:

General

Ship

I

Shore/ Terminal

9

Is the cargo t ransfer system sufficiently isolated and drained to allow safe removal of blank flanges prior to connection?

10

Are scuppers effectively plugged and drip trays in position, both on board and ashore?

R

11

Will temporarily removed scupper plugs be moni tored constantly?

R

12

Are shore spill containment and sumps correctly managed?

R

13

Are 1he ship's unused cargo and bunker connections properly secured with blank flanges and fully bolted'

14

Are the shore's unused cargo and bunker connecaons properly secured with blank flanges and fully bolted?

15

Are all cargo, ballast and bunker tank lids dosed?

16

Remarks

Code

'

Are sea and overboard discharge

valves, when not in use, closed and visibly secured' '

General

17

18

Ship

I

Shore/ Terminal

Code

Are all external doors, portholes and windows in the accommodation, stores and machinery spaces closed? Are ship's emergency fire control plans located externally?

R

Location:

.

-

19

Are fixed IG pressure and oxygen cont em recorders working?

R

20

Are all cargo tank atmospheres at positive pressure with an oxygen content of 8% or less by volume?

PR

.

.

•

21

Is the ship ready to move under its own power?

PR

22

Is there an effective deck watch in attendance on board and adequate supervision on the terminal and on the ship?

R

Are sufficient personnel on board and ashore to deal with an emergency?

R

Have the procedures for cargo, bunker and ballast handling been agreed?

AR

23

24

Remarks

General

Ship

I 25

26

Shore/ Terminal

Code

Has the emergency signal and shutdown procedure to be used by the ship and shore been explained and understood?

A

Have Matenal Safety Data Sheets (MSDS) for the cargo transfer been exchanged?

p

27

Have the hazards associated wi th toxic substances in the cargo being handled been identified and understood?

28

Has an International Ship/Shore Fire Connection been provided?

29

Is the agreed tank venting system being used?

30

If the ship is capable of closed loading, have the requirements for closed operations been agreed?

31

Has the operatton of the PN valves and/or high velocrty vents been verified?

32

If a vapour return line has been connected, have operating procedures been agreed?

A

Are Independent high level alarms fitted, if so are they operational and ha'te they been tested?

A

33

PR

Remarks

General

Ship

I

Shore/ Terminal

Code

34

Are adequaie insulating means m place in theshiplshore connection?

A

35

Are shore lines fitted w ith a non-return valve, or are agreed procedures m place to avoid back filling?

p

36

Are smoking regulations being observed?

AR

37

Are naked light regulations being observed?

AR

38

Are shiplshore telephones, mobile phones and pager requirements being obse1ved?

AR

39

Are hand torches and personal equipment of an approved type?

40

Are fixed UHFMiF transceivers and AIS equipment on the correct power mode or switched off? I·

41

Are portable VHF/UHF t ransceivers of an approved type?

42

Are the ship's main radio transmitter aenals earthed and radars switched off?

43

Are electric cables to portable electrical equipment disconnected from power?

Remarks

General

44

Are wmdow type air conditioning units disconnected?

45

Are arrangements in place for positive pressure to be maintained inside the accommodation. and are air concitioning intakes, which may permit the entiy of cargo vapours, closed?

46

Are measures in place to ensure sufficient mechanKal ventilation in the pumproom?

Ship

I

Shore/ Terminal

Code

R

47

Is there prov1S1on for an emergency escape?

48

Have the maximum wind and swell criteria for operations been agreed?

A

49

Have se
A

so

Where appropriate, have

procedures been agreed for receiving nitrogen supplied from shore, either for inerting or purging ship's tanks, or line clearing Into the ship?

Remarks

AP

Criteria:

General

Ship

I 51

Is the mert gas system fully operational and in good working order?

I

Shore/ Terminal

p

,,

52

Are deck seals or equivalent m good working order?

R

53

Are liquid levels in PN breakers correct'

R

54

Have the fixed and portable oxygen analysers been cahbrated and are they working properly?

R

55

Are all the individual tank IG valves (if fitted) correctly set and locked?

R

56

Are all the persons in charge of cargo operations aware that in the case of failure of t he mert gas plant, discharge operations should cease and the terminal be advised?

•

.. - . . . ..

~

.

57

Are tank cleaning operations planned during the ship's stay alongside the shore installation?

58

If 'yes', have the procedures and approvals for tank cleaning been agreed with shore authorities?

59

Remarks

Code

Has permrssion been granted for gas freeing operations'

"

~

1 ..

..

,.

,.

..

.

lJ,.

.

•

.•. .. ··.

.

-

~

60

Are Material Safety Data Sheets available giving the necessary data for the safe handling of the cargo?

61

Is a manufactu rer~ inhibitor certificate available?

62

Is sufficient and suitable protective equipment (Including SelfContained Breathing Apparatus) and protective clothing ready for immediate use?

63

Have counter measures in the event of accidental personal contact wrth the cargo been agreed?

64

Is the cargo handling rate compatible with the automatic shutdown system, if In use?

65

Are cargo system gauges and alarms correaly set and In good order?

66

Are portable vapour detection ins1ruments readily available for the products to be handled?

67

Has information on firefighting media and procedures been exchanged?

p

A

General

Ship

I 68

Shore/ Terminal

Remarks

Code

Are transfer hoses of a surtable material, resistant to the chemical action of the (argoes?

,

69

Is cargo handhng being performed w ith permanent installed pipelines?

p

70

Where appropriate, have procedures been qgreed for receiving nitrogen supplied from shore, either for inerting or purging ship's tanks, or line clearing into the ship?

AP

JOINT DECLARATION We the undersigned have checked, where appropriate jointly. the items on this Checklist and have satisfied ourselves that the entries we have made are correct to the best of our knowledge. We have also made arrangements to carry out repetitive checks as necessary and agreed that those items with the letter 'R' in the Checklist should be re-checked at inteivals not exceeding _ _ hours.

If to our knowledge the status of any item changes, we will immediately inform the other party. For Ship:

Position: _ _ _ _ Name _ _ _ _ _ _ _ _ _ _ _ _ _ Signature _ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ (Tirne)

_ _ _ _ _ _ _ _ _ (Date - DDIMMIYYYY)

For Shore:

Position: _ _ _ _ Mame _ _ _ _ _ _ _ _ _ _ _ _ _ Signature _ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ (Time) Record of repetitive checks:

_ _ _ _ _ _ _ _ _ (Date - DDIMM/YYYY}

SHIP/ SHORE SAFETY CHECKLIST GUIDELINES

The presence of the letters'/ rel="nofollow">:, 'P', 'R', or a combination of letters in the Code column indicates the following:

A

Any referenced procedures and agreements should be in writing in the remarks column of the Checklist or other mutually acceptable form

p

In the case of a negative answer the operation should not be carried out without permission of the port authority

R

Items to be re-checked during the operation at intervals not exceeding that agreed in the declaration

I Code I Remarks

General

..-. . -· ,, '• '· :•_ - . ~ PART APhysical Checks General : ·- ::' __ ,._.,_,_ .......... .,,.,__,,., ~----

1

'

,

~-···

Is there safe access between ship and shore?

R

The access should be positioned as far away from the manifolds as practicable. The means of access to the ship should be safe and may consist of an appropriate gangway or accommodation ladder with a properly secured safety net fitted to it. Part1Cular attention to safe access should be given where the difference in level between the point of access on the ship and the jetty or quay is large, or is likely to become large. When terminal access facilities are not available and a ship's gangway is used, there should be an adequate landing area on the berth so as to provide the gangway with a sufficient clear run of space and so maintain safe and convenient access to the ship at all states of tide and changes in the ship's freeboard. Near the access ashore, appropriate life-saving equipment should be provided by the terminal. A lifebuoy should be available on board the ship near the gangway or accommodation ladder. The access should be safely and properly illuminated during darkness. Persons who have no legitimate business on board, or who do not have the Master's permission, should be refused access to the ship. The terminal should control access to the jetty or berth in agreement with the ship.

General

2

Is the ship securely moored?

I Code I Remarks R

When considering this item, due regard should be given to the need for adequate tendering arrangements. Ships should remain adequately secured at their moorings. Alongside piers or quays, ranging of the ship should be prevented by keeping all mooring lines taut. Attention should be given to the movement of the ship caused by wind, currents, tides or passing ships and the operation in progress. Wire ropes and fibre ropes should not be used together in the same direction (i.e. as breast lines, spring lines, head or stern lines) because of the difference in their elastic properties. Once moored, ships fitted with automatic tension winches should not use such winches in the automatic mode. Means should be provided to enable quick and safe release of the ship in case of an emergency. In ports where anchors are required to be used, special consideration should be given to this matter. Irrespective of the mooring method used, the emergency release operation should be agreed, taking into account the possible risks involved. Anchors not in use should be properly secured.

3

Is the agreed ship/ shore communication system operative?

AR

Communication should be maintained in the most efficient way between the responsible officer on duty on the ship and the terminal representative. When telephones are used, the telephone both on board and ashore should be continuously manned by a person who can immediately contact their respective supervisor. Additionally, the supervisor should have a facility to override all calls. When radios are used, the units should be carried by the supervisor or a person who can get in touch with their respective supervisor immediately. Where fixed systems are used, the guidelines for telephones should apply. The selected primary and back up systems of communication should be recorded on the checklist and necessary information on telephone numbers and/or channels to be used should be exchanged and recorded. The telephone and portable radio systems should comply with the appropnate safety requirements.

TANKER SAFETY GUIDE (CHEMICAl.Sl

General 4

Are emergency towing-off pennants (firewires) correctly rigged and posrtioned (where applicable)?

I Code I Remarks R

Tanker industry experience does not support the use of emergency towmg-off pennants (firewires). However, some terminals still require the rigging of towing-off pennants fore and aft on the offshore side of the ship. When their use is required, and unless the terminal specifically advises to the contrary, emergency towingoff pennants (firewires) should be positioned on both the off-shore bow and quarter of the ship. At a buoy mooring, emergency towing-off pennants should be positioned on the side opposite to the hose string. There are various methods for rigging emergency towingoff pennants currently in use. Some terminals may require a particular method to be used and the ship should be advised accordingly.

5

Are the ship's fire hoses and fire-fighting equipment positioned and ready for immediate use?

R

Fire-fighting equipment on board should be correctly positioned and ready for immediate use. Adequate units of fixed or portable equipment should be stationed to cover the ship's cargo deck and the jetty area, having due regard to the presence of both the ship and nearby shore tanks. The ship's fire-main systems should be pressurised or be capable of being pressurised at short notice. Both ship and shore should ensure that their fire-main systems can be inter-connected in a quick and easy way lil:ilising, if necessary, the International Ship/Shore Fire Connection.

6

Are the shore's fire hoses and fire-fighting equipment positioned and ready for immediate use?

R

Fire-fighting equipment on the jetty should be correctly positioned and ready for immediate use. Adequate units of fixed or portable equipment should be stationed to cover the ship's cargo deck and the jetty area, having due regard to the presence of both the ship and nearby shore tanks. The shore's fire-main systems should be pressurised or be capable of being pressurised at short notice. Both ship and shore should ensure that their fire-main systems can be inter-connected in a quick and easy way lJtilising, if necessary, the International Ship/Shore Fire Connection.

7

Are the ship's cargo and bunker hoses/arms. pipelines and manifolds in good condition, properly rigged and appropriate for the service intended?

Hoses should be in a good condition and properly fitted and rigged so as to prevent strain and stress beyond design limitations. All flange connections should be fully bolted and any other types of connections should be properly secured. Hoses and pipelines and metal arms should be constructed of a material suitable for the substance to be handled, taking into account its temperature and the maximum operating pressure. Cargo hoses should be indelibly marked so as to allow the identification of the products for which they are suitable, specified maximum working pressure, the test pressure and last date of testing at this pressure. If to be used at temperatures other than ambient, maximum and minimum service temperatures should be marked.

8

Are the shore's cargo and bunker hoses/arms, pipelines and manifolds in good condition, property rigged and appropriate for the service intended ?

Hoses should be in a good condition and properly fitted and rigged so as to prevent strain and stress beyond design limitations. All flange connections should be fully bolted and any other types of connections should be properly secured. Hoses and pipelines and metal arms should be constructed of a material suitable for the substance to be handled, taking into account its temperature and the maximum operating pressure. Cargo hoses should be indelibly marked so as to allow the identification of the products for which they are suitable, specified maximum working pressure, the test pressure and last date of testing at this pressure. If to be used at temperatures other than ambient, maximum and minimum service temperatures should be marked.

9

ls the cargo transfer system

sufficiently isolated and drained to allow safe removal of blank flanges prior to connection?

TANKER SAFETY GUIDE (CHEMICAl.Sl

A positive means of confirming that both ship and shore cargo systems are isolated and drained should be in place and used to confirm that it is safe to remove blank flanges prior to connection. The means should provide protection against polluuon due to unexpected and uncontrolled release of product from the cargo system and injury to personnel due to pressure in the system suddenly being released in an uncontrolled manner.

General 10

Are scuppers effectively plugged and dnp trays in position, both on board and ashore?

I Code I Remarks R

Where applicable, all scuppers on board should be properly plugged during the operations. Accumulation of water should be drained off periodically. The ship's manifolds should ideally be provided with fixed drip trays in accordance with recommendations, where applicable. In the absence of fixed containment, portable drip trays should be used. All drip trays should be emptied in an appropriate manner whenever necessary but always after completion of the specific operation. When only corrosive liquids or refrigerated gases are being handled, the scuppers may be kept open, provided that an ample supply of water is available at all times in the vicinity of the manifolds.

11

Will temporarily removed scupper plugs be monitored constantly?

R

Scuppers that are temporarily unplugged, in order to drain clean rainwater from the cargo deck for example, must be constantly and closely monitored. The scupper must be re-sealed immediately in the event of a deck cargo spill or any other incident that has the potential to cause pollution.

12

Are shore spill containment and sumps correctly managed?

R

Shore containment facilities, such as bund walls, drip trays and sump tanks, should be properly maintained, having been sized for an appropriate containment volume following a realistic risk assessment. Jetty manifolds should ideally be provided with fixed drip trays; in their absence, portable drip trays should be used. Spill or slop transier facilities should be well maintained and, if not an automatic system, should be readily available to deal with spilled product or rainwater.

13

Are the ship's unused cargo and bunker connections properly secured with blank flanges and fully bolted?

Unused cargo and bunker connections should be closed and blanked. Blank flanges should be fully bolted and other types of fittings, if used, properly secured.

14

Are the shore's unused cargo and bunker connections properly secured with blank flanges and fully bolted?

Unused cargo and bunker connections should be dosed and blanked. Blank flanges should be fully bolted and other types of fittings, if used, properly secured.

15

Are all cargo, ballast and bunker tank lids closed?

Apart from the openings in use for tank venting (see Question 29), all openings to cargo, ballast and bunker tanks should be closed and gas-tight. Ullaging and sampling points may be opened for the short penods necessary for ullaging and sampling, activities which should be conducted taking account of the controls necessary to avoid electrostatic discharge. Closed ullaging and sampling syst ems should be used where required by international, national or local regulations and agreements.

16

Are sea and overboard discharge valves, when not in use, closed and visibly secured?

Experience shows the importance of this item in pollution avoidance on ships where cargo lines and ballast systems are interconnected. Remote operating controls for such valves should be identified in order to avoid inadvertent opening. If appropnate, the security of the valves in quest ion should be checked visually.

17

Are all external doors, portholes and windows in the

R

accommodation, stores and machinery spaces closed?

18

Are ship's emergency fire control plans located externally?

External doors, windows and portholes in the accommodation should be closed during cargo operations. These doors should be clearly marked as bemg required to be closed during such operations, but at no time should they be locked . A set of fire control plans should be permanently stored in a prominently marked weather-tight enclosure outside the accommodation block for the assistance of shoreside fire-fighting personnel. A crew list should also be included in this enclosure.

If oie ship is fitted, or is required to be fitted, 'with an inert ' the following statements should be addressed:

19

Are fixed IG pressure and oxygen content recorders working?

R

gas system

All fixed and portable oxygen content recorders should be tested and checked as required by the company and/or manufacturers' instructions and should be operating correctly. The calibration certificate should show that its validity is as required by the ship's SMS.

20

Are all cargo tank atmospheres at positive pressure with an oxygen content of 8% or less by volume?

TANKER SAFETY GUIDE (CHEMICAl.Sl

PR

Pnor to commencement of cargo operations, each cargo tank atmosphere should be checked to verify an oxygen content of 8% or less by volume. lnerted cargo tanks should be kept at a positive pressure at all times.

General

I Code I Remarks

PART B - Verbal Verification

21

Is the ship ready to move under its own power?

PR

The ship should be able to move under its own power at short notice, unless permission to 1mmob11tse the ship has been granted by the port authority and the Terminal Representauve. Certain conditions may have to be met for permission to be granted.

22

Is there an effective deck watch in attendance on board and adequate supervision on the terminal and on the ship?

R

The operation should be under constant control and supervision on the ship and in the terminal. Supervision should be aimed at preventing the development of hazardous situations. However, if such a situation arises, the controlling personnel should have adequate knowledge and the means available to take corrective action. The controlling personnel on the ship and in the terminal should maintain effective communications with their respective supervisors. All personnel connected with the operations should be familiar with the dangers of the substances handled and should wear appropriate protective clothing and equipment.

23

Are sufficient personnel on board and ashore to deal with an emergency?

R

At all times during the ship's stay at the terminal, a sufficient number of personnel should be present on board the ship and in the shore installation to deal with an emergency.

General 24

Have the procedures for cargo, bunker and ballast handling been agreed?

I Code I Remarks AR

The procedures for the intended operation should be pre-planned. They should be discussed and agreed upon by the Responsible Officer and Terminal Representative prior to the start of the operations. Agreed arrangements should be formally recorded and signed by both the Responsible Officer and Terminal Representative. Any change in the agreed procedure that could affect the operation should be discussed by both parties and agreed upon. After both parties have reached agreement, substantial changes should be recorded in writing as soon as possible and in sufficient time before the change in procedure takes place. In any case, the change should be laid down in writing within the working penod of those supervisors on board and ashore in whose working period agreement on the change was reached. The operations should be suspended and all deck and vent openings closed on the approach of an electrical storm. The properties of the substances handled, the equipment of ship and shore installation, and the ability of the ship's crew and shore personnel to execute the necessary operations and to sufficiently control the operations are factors which should be taken into account when ascertaining the possibility of handling a number of substances concurrently. The manifold areas, both on board and ashore, should be safely and properly illuminated during darkness. The initial and maximum loading rates, topping off rates and normal stopping times should be agreed, having regard to: •

The nature of the cargo to be handled;

•

The arrangement and capacity of the ship's cargo lines and gas venting systems;

•

The maXJmum allowable pressure and flow rate in the ship/shore hoses and loading arms;

•

Precautions to avoid accumulation of static electricity; and

•

Any other flow control limitations.

A record to this effect should be formally made as above.

TANKER SAFETY GUIDE (CHEMICAl.Sl

General

25

Has the emergency signal and shutdown procedure to be used by the ship and shore been explained and understood?

I Code I Remarks A

The agreed signal to be used in the event of an emergency arising ashore or on board should be clearly understood by shore and ship personnel. The agreement should state the circumstances in which operations have to be stopped immediately. An emergency shutdown procedure should be agreed between ship and shore, formally recorded and signed by both the Responsible Officer and Terminal Representative. The agreement should state the circumstances in which operations have to be stopped immediately. Due regard should be given to the possible introduction of dangers associated with the emergency shutdown procedure.

26

27

Have Material Safety Data Sheets (MSDS) for the cargo transfer been exchanged ?

p

An MSDS should be available to the receiver from the terminal or ship supplying the product. As a minimum, such information sheets should provide the constituents of the product by chemical name, name in common usage, UN number and the maximum concentration of any toxic components, expressed as a percentage by volume or as ppm.

Have the hazards associated with toxic substances in the cargo being handled been identified and understood?

Many tanker cargoes contain components that are known to be hazardous to human health. In order to minimise the impact on personnel, information on cargo constituents should be available during the cargo transfer to enable the adoption of proper precautions. In addition, some port states require such information to be readily available during cargo transfer and in the event of an accidental spill. This is particularly relevant to cargoes that could contain H2S, benzene or lead additives.

28

Has an International Ship/ Shore Fire Connection been provided?

29

Is the agreed tank venting system being used?

The connection must meet the standard requirements and, if not actually connected prior to commencement of operations, should be readily available for use in an emergency. PR

Agreement should be reached and recorded as to the venting system to be used for the operation, taking into account the nature of the cargo and international, national or local regulations and agreements. There are three basic systems for venting tanks:

1. Open to atmosphere via open ullage ports, protected by suitable flame screens; 2.

Fixed venting systems which includes inert gas systems; and

3.

To shore through a vapour collection system (see Question 32).

30

If the ship is capable of closed loading, have the requirements for closed operatJons been agreed?

It is a requirement of many terminals that, when the ship is ballastJng into cargo tanks, loading or discharging, it operates without recourse to opening ullage and sighting ports. In these cases, ships will require the means to enable closed monitoring of tank contents, either by a fixed gauging system or by using portable equipment passed through a vapour lock, and preferably backed up by an independent overfill alarm system.

31

Has the operation of the PN valves and/or high velocity vents been verified?

The operation of the PN valves and/or high velocity vents should be checked using the testing facility provided by the manufacturer. Furthermore, it is imperative that an adequate check is made, visually or otherwise, to ensure that the checklift 1s actually operating the valve. On occasion, a seized or stiff vent has caused the checklift drive pin to shear and the ship's personnel to assume, with potentially disastrous consequences, that the vent was operational.

32

If a vapour return line has

A

been conneaed, have operating procedures been agreed?

Where required, a vapour return line will be used to return f lammable vapours from the cargo tanks to shore. The maxim um and minimum operating pressures and any other constraints associated with the operation of the vapour return system should be discussed and agreed by ship and shore personnel.

33

Are independent high level alarms fitted, if so are they operational and have they been tested?

A

Owing to the increasing reliance placed on gauging systems for closed cargo operations, it is important that such systems are fully operational and that back up is provided in the form of an independent overfill alarm arrangement. The alarm should provide audible and visual ind1catJon and should be set at a level that will enable operations to be shutdown prior to the tank being overfilled. Under normal operations, the cargo tank should not be filled higher than the level at which the overfill alarm is set Individual overfill alarms should be tested at the tank to ensure their proper operation pnor to commencing loading unless the system is provided with an electJonic self-testing capability which monitors the condition of the alarm circuitry and sensor and confirms the instrument set point.

TANKER SAFETY GUIDE (CHEMICALS>

General 34

Are adequate insulating means in place in the ship/ shore connection?

I Code I Remarks A

Unless measures are taken to break the continuous electrical path between ship and shore pipework provided by the ship/shore hoses or metallic arms, stray electric currents, mainly from corrosion prevention systems, can cause electric sparks at the flange faces when hoses are being connected and disconnected. The passage of these currents is usually prevented by an insulating flange inserted at each jetty manifold outlet or incorporated in the construction of metallic arms. Alternatively, the electrical discontinuity may be provided by the inclusion of one length of electrically discontinuous hose in each hose string. It should be ascertained that the means of electrical discontinuity is in place, that it is in good condition and is not being by-passed by contact with an electrically conductive material.

35

Are shore lines fitted with a non-return valve, or are agreed procedures in place to avoid back filling?

36

Are smoking regulations being observed?

p

In order to avoid cargo running back when discharge from a ship is stopped, either due to operational needs or excessive back pressure, the terminal should confirm that it has a positive system that will prevent unintended flow from the shore facility onto the ship. Alternatively, a separate procedure should be agreed that will directly protect the ship.

AR

Smoking on board the ship may only take place in areas specified by the Master in consultation with the Terminal Representative. No smoking is allowed on the jetty and the adjacent area, except in buildings and places specified by the Terminal Representative in consultation wrth the Master. Places that are directly accessible from the outside should not be designated as places where smoking is permitted. Buildings, places and rooms designated as areas where smoking is permitted should be clearly marked as such.

37

Are naked light regulations being observed?

AR

A naked light or open fire comprises the following: flame, spark formation, naked elearic light or any surface with a temperature that is equal to or higher than the auto-ignition temperature of the products handled in the operation. The use of naked lights or open fires on board the ship, and within a distance of 2 5 metres of the ship, should be prohibited, unless all applicable regulations have been met and agreement reached by the port authority, Terminal Representative and the Master.

General

38

Are ship/shore telephones, mobile phones and pager requirements being observed?

I Code I Remarks AR

Ship/shore telephones should comply with the requirements for explosion-proof construCllon, except when placed and used in a safe space in the accommodation. Mobile telephones and pagers should not be used in hazardous areas unless approved for such use by a competent authority.

39

Are hand torches and personal equipment of an approved type?

Battery operated hand torches (flashlights) should be of a safe type, approved by a competent authority. Damaged units, even though they may be capable of operation, should not be used.

40

Are fixed UHFNHF transceivers and AIS equipment on the correct power mode or switched off?

Fixed VHF/UHF and AIS equipment should be switched off or on low power (1 watt or less) unless the Master, in consultation with the Terminal Representative, has established the conditions under which the installation may be used safely.

41

Are portable VHF/UHF transceivers of an approved type?

Portable VHF/UHF sets should be of a safe type, approved by a competent authority.

42

Are the ship's main radio transmitter aerials earthed and radars switched off?

The ship's main radio station should not be used during the ship's stay in port, except for receiving purposes. The main transmitting aerials should be disconnected and earthed. Satellite communications equipment may be used normally, unless advised otherwise. The ship's radar installation should not be used unless the Master, in consultation with the Terminal Representative, has established the conditions under which the installation may be used safely.

43

Are electric cables to portable electncal equipment disconnected from power?

The use of portable electncal equipment on wandering leads should be prohibited in hazardous zones during cargo operations, and the equipment preferably removed from the hazardous zone. Telephone cables in use in the ship/shore communication system should preferably be routed outside the hazardous zone. Wherever this is not feasible, the cable should be so positioned and protected that no danger arises from its use.

44

Are window type air conditioning units disconnected?

TANKER SAFETY GUIDE (CHEMICAl.Sl

Window type air conditioning units should be disconnected from their power supply.

45

Are arrangements in place for positJve pressure to be maintained inside the accommodation, and are air conditioning intakes, which may permit the entry of cargo vapours, closed?

46

Are measures m place to ensure suffiaent mechanical ventilation in the pump room?

47

Is there provision for an emergency escape?

48

Have the maximum wind and swell cmeria for operations been agreed?

A positive pressure should, when possible, be maintained inside the accommodation, and procedures or systems should be m place to prevent flammable or toxic vapours from entering accommodation spaces. This can be achieved by air conditioning or similar systems, which draw clean air from non-hazardous locations. Air conditioning systems should not be operated on 100% recirculation. R

Pumprooms should be mechanically ventilated and the ventilation system, which should maintain a safe atmosphere throughout the pumproom, should be kept running throughout cargo handling operations. The gas detection system, if fitted, should be functioning correctly. In addition to the means of access referred to in Question 1, a safe and quick emergency escape route should be available both on board and ashore. On board the ship, it may consist of a lifeboat ready for immediate use, preferably at the alter end of the ship, and clear of the moorings.

A

There are numerous factors which will help determine whether cargo or ballast operations should be discontinued. Discussion between the terminal and the ship should identify limiting factors, which could include:

•

Wind speed and direction and the effect on hard arms;

•

Wind speed and direction and the effect on mooring integrity;

•

Wind speed and directJon and the effect on gangways; and

•

At exposed terminals, swell effects on moorings or gangway safety.

Such limitations should be clearly understood by both parties. The criteria for stopping cargo, disconnecting hoses or arms and vacating the berth should be written in the 'Remarks' column ot the checklist.

49

Have security protocols been agreed between the Ship Security Officer and the Port Facility Security Officer, if appropriate?

A

In states that are signatones to SOLAS, the ISPS Code requires that the Ship Security Officer and the Port Facility Security Officer co-ordinate the implementation of their respective security plans with each other.

General 50

Where appropriate, have procedures been agreed for receiving nitrogen supplied from shore, either for inerting or purging ship's tanks, or line clearing into the ship?

I Code I Remarks AP

Ship and shore should agree in writing on the inert gas supply, specifying the volume required, and the flow rate in cubic metres per minute. The sequence of opening valves before beginning the operation and after completion should be agreed, so that the ship remains in control of the flow. Attention should be given to the adequacy of open vents on a tank in order to avoid the possibility of over pressurisation. The tank pressure should be closely monitored throughout the operation. The ship's agreement should be sought when the terminal wishes to use compressed nitrogen (or air) as a propellant, either for pigging to clear shore lines into the ship or to press cargo out of shore containment. Nerther of these practices are generally recommended. The ship should be informed of the pressure to be used and the possibility of receiving gas into a cargo tank.

I~ If the ship is fitted, or is required to.be fitted; "Yith an in~rt gas syste_m . the follqwing .s tatements shou.l d be ~~dressed: 51

Is the inert gas system fully operational and in good working order?

p

The inert gas system should be in safe working condition with particular reference to all interlocking trips and associated alarms, deck seal, non-return valve, pressure regulating control system, main deck IG line pressure indicator, individual tank IG valves (when fitted) and deck PN breaker. Individual tank IG valves (if fitted) should have easily identified and fully functioning open/d ose position indicators.

52

Are deck seals or equivalent in good working order?

R

It 1s essential that the deck seal arrangements are in a safe condition. In particular, the water supply arrangements to the seal and the proper functioning of associated alarms should be checked.

53

Are liquid levels in PN breakers correct?

R

Checks should be made to ensure that the liquid level in the PN breaker complies with manufacturer's recommendations.

54

Have the fixed and portable oxygen analysers been calibrated and are they working properly?

R

All fixed and portable oxygen analysers should be tested and checked as required by the company and/or manufacturers' instructions and should be operating correctly. The in-line oxygen analyser/recorder and sufficient portable oxygen analysers should be working properly. The calibration certificate should show that its validity is as required by the ship's SMS.

TANKER SAFETY GUIDE (CHEMICAl.Sl

General 55

Are all the individual tank IG valves (if fitted) correctly set and locked?

I Code I Remarks R

For both loading and discharge operations, it is normal and safe to keep all individual tank IG supply valves (if fitted) open in order to prevent inadvertent under or over pressurisation. In this mode of operation, each tank pressure will be the same as the deck main IG pressure and thus the PN breaker will act as a safety valve in case of excessive over or under pressure. If individual tank IG supply valves are closed for reasons of potential vapour contamination or depressurisation for gauging etc, then the status of the valve should be clearly indicated to all those involved in cargo operations. Each individual tank IG valve should be fitted with a locking device under the control of the Responsible Officer.

56

Are all the persons m charge of cargo operations aware that in the case of failure of the inert gas plant, discharge operations should cease and the terminal be advised?

In the case of failure of the IG plant, the cargo discharge, deballasting and tank cleaning operations should cease and the terminal be advised.

57

Are tank cleaning operations planned during the ship's stay alongside the shore installation?

During the pre-transfer discussion between the Responsible Officer and Terminal Representative, it should be established whether any tank cleaning operations are planned while the ship is alongside and the checklist should be annotated accordingly.

58

If 'yes', have the procedures and approvals for tank cleaning been agreed w ith shore authonties?

It should be confirmed that all necessary approvals that may be required to enable tank cleaning to be undertaken alongside have been obtained from relevant authorities. The method of tank cleaning to

Under no circumstances should the ship's officers allow the atmosphere in any tank to fall below atmospheric pressure.

be used should be agreed, together with the scope of the operation. 59

Has permission been granted for gas freeing operations?

It should be confirmed that all necessary approvals that may be required to enable gas freeing to be undertaken alongside have been obtained from the relevant authorities.

Are Material Safety Data Sheets available giving the necessary data for the safe handling of the cargo?

Information on the product to be handled should be available on board the ship and ashore and should include: a full description of the physical and chemical properties, including reactivity, necessary for the safe containment and transfer of the cargo; action to be taken in the event of spills or leaks; countermeasures against accidental personal contact; and fire-fighting procedures and fire-fighting media.

General

61

62

63

Is a manufacturer's inhibitor certificate available?

Is sufficient and suitable protective equipment (including Self-Contained Breathing Apparatus) and

I Code I Remarks p

Where cargoes are required to be stabilised or inhibited in order to be handled, ships should be provided with a certificate from the manufacturer stating: •

Name and amount of inhibitor added;

•

Date inhibitor was added and the normal duration of its effectiveness;

•

Whether the inhibitor is oxygen dependent and if so the minimum level of oxygen required in the vapour space;

•

Any temperature limitations affecting the inhibitor; and

•

The action to be taken should the length of the voyage exceed the effective lifetime of the inhibitor.

Suitable protective equipment (including Self-Contained Breathing Apparatus and protective clothing) appropriate to the specific dangers of the product handled, should be readily available in sufficient quantity for operational

protective clothing ready for immediate use?

personnel both on board and ashore.

Have counter measures in the event of accidental personal contact with the cargo been agreed?

Sufficient and suitable means should be available to neutralise the effects and remove small quantities of spilled products. Should unforeseen personal contact occur, in order to limit the consequences it 1s important that sufficient and suitable countermeasures are undertaken. The MSDS should contain information on how to handle such contact with reference to the special properties of the cargo, and personnel should be aware of the procedures to follow. A suitable safety shower and eye rinsing equipment should be fitted and ready for instant use in the immediate vicinity of places on board or ashore where operations regularly take place.

TANKER SAFETY GUIDE (CHEMICAl.Sl

General 64

Is the cargo handling rate compatible with the automatic shutdown system, if in use?

I Code I Remarks A

Automatic shutdown valves may be fitted on the ship and ashore. The action of these is automatically initiated by, for example, a certain level being reached in the ship or shore tank being filled. Where such systems are used, the cargo handling rate should be established to prevent pressure surges from the automatic closure of valves causing damage to ship or shore line systems. Alternative means, such as a recirculation system and buffer tanks, may be fitted to relieve the pressure surge created. A written agreement should be made between the Responsible Officer and Terminal Representative indicating whether the cargo handling rate will be adjusted or alternative systems will be used.

65

Are cargo system gauges and alarms correctly set and in

Ship and shore cargo system gauges and alarms should be checked regularly to ensure they are in good

good order?

working order. In cases where it is possible to set alarms to different levels, the alarm should be set to the required level.

66

Are portable vapour detection instruments readily available for the products to be handled?

The equipment provided should be capable of measuring, where appropriate, flammable andfor toxic levels. Surtable equipment should be available for operational testing of those instruments capable of measuring flammability. Operational testing should be carried out before using the equipment Calibration should be carried out in accordance with the Safety Management System.

67

Has information on fire-fighting media and procedures been exchanged?

Information should be exchanged on the availability of fire-fighting equipment and the procedures to be followed in the event of a fire on board or ashore. Special attention should be given to any products that are being handled which may be w ater reactive or which require specialised fire-fighting procedures.

68

Are transfer hoses of a suitable material, resistant to the chemical action of the cargoes?

Each transfer hose should be indelibly marked so as to allow the identification of the products for which it is suitable, rts specified maximum working pressure, the test pressure and last date of testing at this pressure, and, rt used at temperatures other than ambient, its maximum and minimum service temperatures.

General

69

Is cargo handling being performed with permanent installed pipelines?

I Code I Remarks p

All cargo transfer should be through permanently installed pipeline systems on board and ashore. Should rt be necessary, for specific operational reasons, to use portable cargo lines on board or ashore, care should be taken to ensure that these lines are correctly positioned and assembled in order to minimise any additional risks associated with their use. Where necessary, the elearical continuity of these lines should be checked and their length should be kept as short as possible. The use of non-permanent transfer equipment inside tanks is not generally permitted unless specific approvals have been obtained. Whenever cargo hoses are used to make connections within the ship or shore permanent pipeline system, these connections should be properly secured, kept as short as possible and be electrically continuous to the ship and shore pipeline respectively. Any hoses used must be suitable for the service and be properly tested, marked and certified.

70

Where appropriate, have procedures been agreed for receiving nitrogen supplied from shore, either for inerting or purging ship's tanks, or line clearing into the ship?

AP

Ship and shore should agree in writing on the inert gas supply, specifying the volume required, and the flow rate in cubic metres per minute. The sequence of opening valves before beginning the operation and after completion should be agreed, so that the ship remains in control of the flow. Attention should be given to the adequacy of open vents on a tank in order to avoid the possibility of over pressurisation. The tank pressure should be closely monitored throughout the operation. The ship's agreement should be sought when the terminal wishes to use compressed nitrogen (or air) as a propellant, either for pigging to clear shore lines into the ship or to press cargo out of shore containment. Pigging the shore line to the ship's tanks should, wherever possible, be avoided due to safety nsks to personnel and to the ship. The ship should be informed of the pressure to be used and the possibility of receiving gas into a cargo tank.

TANKER SAFETY GUIDE (CHEMICAl.Sl

MATERIAL SAFETY DATA SHEET (MSDS)

Material Name MSDS Version Number Effective Date: _ I _ I _ _ (DD/MM/YYYY) 1. Identification of the substance or mixture and of the supplier Name of Category: Name of Substance/Product: Trade Name of Substance: Description on Bill of Lading (B/L), Bunker Delivery Note/Shipping Document: Other Means of Identification:

Note: Product name as it appears in /BC Code or MEPC.2/Circ should be provided Suppliers/Manufacturers' Details: Name: Address: Telephone Number: EMERGENCY CONTACT NUMBER:

2. Hazards identification GHS Classification: GHS Label Elements Symbol(s): GHS Hazard Statements: Signal Words: GHS Precautionary Statements Prevention: Response: Storage: Disposal: Other Hazards which do not result in Classification:

Material Name MSDS Version Number Effective Date: _ / _ / _ _ (DD/MM/YYYY)

3. Composition/information on ingredients Common Name: Synonyms: Preparation Description: Additional Information:

Note: Hazardous ingredients such as inhibitors, denaturing agents etc. must be listed

4. First aid measures '

Inhalation: Skin Contact: Eye Contact: Ingestion: Most Important Symptoms/Effects. Acute & Delayed: Recommended Immediate Medical Attention and Speaal Treatment:

5. Fire-fighting measures Specific Hazards Arising from the Chemical: Suitable Extinguishing Media (including equipment and techniques): Unsuitable Extinguishing Media: Special Protective Equipment and Precautions for Fire-Fighters:

6. Accidental release measures Personal Precautions, ProteCllve Equipment and Emergency Procedures: Environmental Precautions: Methods and Materials for Containment and Clean-up: Additional Advice:

TANKER SAFETY GUIDE (CHEMICAl.Sl

Material Name MSDS Version Number Effective Date: _ I _ I _ _ (DD/MM/YYYY)

7. Handling and storage General Precautions: Precautions for Safe Handling: Conditions for Safe Storage: Recommended Materials: Unsuitable Materials: Other Advice (including incompatibilities with other cargoes/products):

8. Exposure controls/personal protection Control Parameters: e.g. Occupational Exposure Limit Values (e.g. PEls, TLVs, MAKs): Appropriate Technical Precautions: Individual Protection Methods: Respiratory Protection: Hand Protection: Eye Protection: Protective Clothing: Thermal Hazards: Monitoring Methods: Environmental Exposure Controls:

Material Name MSDS Version Number Effective Date: _ / _ / _ _ (DD/MM/YYYY)

9. Physical and chemical properties Appearance: (physical state. colour, etc.) Odour. Odour Threshold: pH: Initial Boiling Point and Boiling Range: Pour Point: Flash Point: Melting Point Upper/Lower Flammability or Explosion Limits: Auto-Ignition Temperature: Vapour Pressure: Relative Density: Water Solubility: Solubility in Other Solvents: Dynamic Viscosity: Kinematic Viscosity: Vapour Density (air=l): Evaporation Rate (nBuAc= 1): Flammability:

'

10. Stability and reactivity Chemical Stability: Possibility of Hazardous Reactions: Conditions to Avoid: Incompatible Materials: Hazardous Decomposition Products: Hazardous Polymerisation: Sensitivity to Mechanical Impact:

TANKER SAFETY GUIDE (CHEMICAl.Sl

Material Name MSDS Version Number Effective Date: _ I _ I _ _ (DD/MM/YYYY)

11. Toxicological information Basis for Assessment (including symptons and chronic effects): Likely Routes of Exposure: Acute Oral Toxicity: Acute Dermal Toxicity: Acute Inhalation Toxicity: Skin Corrosion/Irritation: Serious Eye Damage/Irritation: Respiratory Irritation: Respiratory or Skin Sensitisation : Aspiration Hazard: Germ Cell Mutagenic Hazard: Carcinogenicity: Reproductive and Developmental Toxicity: Specific Target Organ Toxicity - Single Exposure: Specific Target Organ Toxicity - Repeated Exposure:

12. Ecological information Basis for Assessment: Acute Toxicity: Fish: Aquatic Invertebrates: Algae: Microorganisams: Mobility/Mobility tn Soil: Persistence/Degradability: Bioaccumulation Potential: Other Adverse Effects:

Material Name MSDS Version Number Effective Date: _ / _ / _ _ (DD/MM/YYYY)

13. Disposal considerations

Information on Safe Handling: Material Disposal: Container Disposal: Local Legislation:

Note: Annex If of MARPOL 73178 also regulates rhe discharge of residues for chemical liquids transported in bulk

,

14. Transport information

UN Number: UN Proper Shipping Name: Ship Type: IBC Code - Product Name, Ship Type and Pollution Category: Transport Hazard Class(es): Special Transport Precautions:

Note: The product name, ship type and pollution category should be provided in this section

'

15. Regulatory information

Safety, Health and Environmental Regulations:

Note: This will include safety, health and environmental regulations specific to the product and designated region, as appropriate

16. Other information

Version Number: Date of Issue (or revision): Issuing Source:

TANKER SAFETY GUIDE (CHEMICAl.Sl

INHIBITED CARGO CERTIFICATE

Issued by: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __

Shipper/Manufadurer/Refinery: - - - - - - - - - - - - - - - - - - - - - - - - Port: _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ Date: _ _ _ _ _ _ _ (DD/MM/YYYY) TerminaVBerth: - - - - - - - - - - - - - - - - - -

Time:--------

This is to certify that, on this day• _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ (DD/MM/YYYY) MV _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ Loaded a cargo o f : - - - - - - - - - - - - - - - - - - - - - - - - - - - - Into cargo t a n k s : - - - - - - - - - - - - - - - - - - - - - - - - - - - - - The above cargo was inhibited on the (date): _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ (DD/MM/YYYY) Name of inhibitor: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ The inhibitor is/is not oxygen dependent Minimum level of oxygen required in the vapour space (if dependent): - - - - - - - - - - - Concentration of inhibitor in c a r g o : - - - - - - - - - - - - - - - - - - - - - - - Duration of effectiveness of inhibitor: - - - - - - - - - - - - - - - - - - - - - - Temperature limitation qualifying the inhibitor's effedive lifetime: - - - - - - - - - - - - - Expected duration of the voyage: - - - - - - - - - - - - - - - - - - - - - - - Has additional inhibitor been s u p p l i e d ? - - - - - - - - - - - - - - - - - - - - - Aet1on to be taken if the duration of the voyage is expected to exceed the life of the inhibitor:

Cargo received on board Date: - - - - - - - - - (DD/MM/YYYY) Port: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ TerminaVberth: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ Master/Chief O f f i c e r : - - - - - - - - - - - - - - - - - - - - - - - - - - - Shore inspector: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

ENCLOSED SPACE ENTRY PERMIT*

This permit relates to entry into any enclosed space and should be completed by 1he Master or responsible person and by any persons entenng the space. e.g. competent person and attendant

General Location of enclosed space(s):

Reason for entry: - - - - - - - - - - - - - - - - - - - - - - - - - - - - Permit valid

From _ _ _ _ _ Date _____ (DD/M ~NYYYY) To

Date

(DDIMM/YYYY)

(See Note 1)

SECTION 1 - PRE· ENTRY PREPARATION 1To be che
Confinned

Initials

I

Has the space been thoroughly ventilated by mechanical means:> Has the space been segregated by blanking off or isolating all connecting pipelines or valves and electrical power/equipment? Has the space been cleaned where necessary? Has the space been tested and found safe for entry? (See Note 2) Pre-entry atmosphere test reaclngs•• (See Note 3):

I Test reading: Oxygen

_ _ % vol (21%)

Hydrocarbon

_ _ % lfl (less than 1%)

Toxic gases

_ _ ppm (less than 50% OEL of the specific gas)

I

Time

I

It should be noted that this is a generic entry permi1 that may be used for all enclosed spaces on board all ships.

**

Note tha1 national requirements may determine t he safe atmosphere range.

TANrER SAFETY GUIDE (CHEMICALS)

Initials

Confirmed

Initials

Confirmed

Initials

Have arrangements been made for regular atmosphere checks to be made while the space is occupied? Have a11angements been made for the space to be continuously ventilated throughout the period of occupation and during work breaks? After work breaks are arrangements in place to ensure re-testing of the atmosphere? Are access and illumination adequate? Is rescue and resuscitation equipment available for immediate use by the entrance to the space? Has an attendant been designated to be in constant attendance at the entrance to the space? Has the officer of the watch (bridge. engine room. cargo control room) been advised of the planned entry? Has a system of communication between all parties been tested and emergency stgnals agreed? Are emergency and evacuation procedures established and understood by all personnel involved with the enclosed space entry? Is all equipment used in good working condition and inspected prior to entry? Are personnel properly clothed and equipped ? SECTION 2 - PRE-ENTRY CHECKS \To bP r hp-k@d by p;i-h p!Y
I

I have received instruct10ns or permisston from the Master or nominated responsible person to enter the enclosed space. Section 1 of this permit has been satisfactorily completed by the Master or nominated responsible person. I have agreed and understand t he communication procedures. I have agreed upon a repo1t ing interval of ............. minutes. Emergency and evacuation procedures have been agreed and are understood. I am aware that the space must be vacated immediately in the event of ventilation failure or if atmosphere tests show a change from agreed safe criteria.

TANKER SA F~TY GUIDE(CH>MICALI)

SECTION 3 - BREATHING APPARATUS AIJD OTHER EQUIPMENT

Confirmed

Initials

!To be che<:ked JOlntly by thE? '"~aster or nominatE?d respnns1blE? person and the person ,vho 1s to enter the space I Those entering the space are familiar with any breathing apparatus to be used. The breathing apparatus has been tested as follows: • Gauge pressure and capacity of air supply; • Low pressure audible alarm if fitted; and • Face mask - unde< positive pressure and not leaking. The means of communication have been tested and emergency signals agreed. All personnel entering the space have been provided wi1h rescue harnesses, multi-gas detectors and, where practicable, lifelines. Signed on completion of Sections 1, 2 and 3 by: Master or nominated responsible p e r s o n · - - - - - - - - - - - - - - - - - - - - - - - Date: _ _ _ _ _ _ _ _ _ _ _ _ _ (00/MM/YYY) Time: _ _ _ _ _ _ _ _ _ _ __ Attendant: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ Date: _ _ _ _ _ _ _ _ _ _ _ _ _ _ (DD/MMIYYY) Time: _ _ _ _ _ _ _ _ _ _ _ __ Person entenng the space: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __

SECTION 5 - COMPLETION OF THE JOB no be completed by the 1espons1ble oe1son supe1 usmg entry1

Job completed· Space secured against entry: OOW informed:

TANrER wnv GUIDE (C H~MICAL5)

Signed upon completion of Sections 4 and 5 by: Responsible person supeivising entry: - - - - - - - - - - - - - - - - - - - - - - - Date. _ _ _ _ _ _ _ _ _ _ _ _ _ (00/MIWYYY) Time. - - - - - - - - - - - -

This permit is rendered invalid should ventilation of the space stop or if any of the conditions noted in the checklis1 change.

Confirmed

SECTION 6 - RE-ENTRY PREPARATION (To be checked by Master or nominated responsible person'

Initials

INhen a break m regt1!ar testing of enclosed space atmosphere occvrs svch as for a refresl1n1et1t or rneai interval, copro,oriate checks as r1?qwr@d under S@ct1on 1, S@ct1on 2 and Sro100 3 musr be complf!i@d prior to rt:-entry to the sp3ce /r> all cases rhe checks listed t1nder Section 6 mus1 additiona!ly be completed Has t~ space R~ent1y

been tested and found S
atmosphere test readings** (See Note 3)

I Test reading Oxygen

_ _ %vol (21%)

Hydrocarbon

_ _ % LFL (less than 1%)

Toxic gases

_ _ ppm (less than 50% OEL of the specific gas)

I

Time

I

Initials

Notes: 1. The Permit should contain a clear lndkatlon as to Its maximum period of validity;

1. In order to obtain a represent.at/Ve cross-section of the space's atmosphere, samples should be taken from several levels and through as many openings as possible. Ventilation should be stopped for about 10 minutes before the pre-entry atmosphere tests are taken; and 3. Tests for specific toxic contaminants, such as benzene or hydrogen sulphide, should be undertaken depending on the nature of the previous contents of the space.

TANKER SA F~TY GUIDE(CH>MICALI)

CARGO HOSE RECORD

Hose Identification _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ Maximum Working Pressure - - - - - - - - - - - - - - - - - - - -

(fhis shot1!d be stendlled or marked on the hose) Working Temp er atures Maximum - - - - - - - - - - - - - - - - - - - - - - - - - - Minimum - - - - - - - - - - - - - - - - - - - - - - - - - - -

(These should be stencilled or marked on the hose) Suitable for Cargoes of

(Any limrtattons on use, or 1n its chemical resistance, should be marked on the hose) Test Pressure and Procedure

(fhis shot1!d give the method of pressurisation and the method of inspection - e.g. measure extension or visuilflY examine fa leaks, and any prec,autions to be taken)

TANrER SAFETY GUIDE (CHEMICALS)

MV _ _ _ _ _ _ _ _ _ _ _ _ _ __

Date _ _ _ _ _ _ _ _ (DD/MMI YYYY)

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RELEVANT INDUSTRY PUBLICATIONS

The latest editions of the following best practice guidelines and tools are also relevant to safe and pollution tree chemical tanker operations {for details see www.ics-shipping.org/publications): International Safety Guide for Oil Tankers and Terminals (ICS, OCIMF, IAPH)* Tanker Safety Guide {Liquefied Gas) {ICS) Ship to Ship Transfer Guide for Petroleum, Chemicals and Liquefied Gases (ICS, OCIMF. SIGTTO, COi)• Bridge Procedures Guide (ICS) Guidelines on the Application of the IMO International Safety Management {ISM) Code {ICS/ISF) Guidelines on the Application of the llO Maritime labour Convention (ICS/ISF) Guide to Helicopter/Ship Operations {ICS) Guidelines on the IMO STCW Convention and Code, including the 2010 'Manila Amendments' {ICS/ISF) ISF Watchkeeper - work/rest hour compliance software {ICS/ISF) Use of l arge Tankers in Seasonal First Year Ice and Severe Sub-Zero Conditions {OCI MF)* Maritime Security: Guidance for Ship Operators on the IMO International Ship and Port Facility Security (ISPS) Code (ICS) Mooring Equipment Guidelines (MEG3) (OCIMF)•

•Published by Witherby Publishing Group