National Association Of Safety Professionals

National Association of Safety Professionals

NASP RISK ASSESSMENT

Risk Assessment Risk assessment is the process of identifying and evaluating a hazard to determine the level of action required to reduce a risk to an acceptable level. It is nothing more than a careful examination of what in the workplace could cause harm to people, so that we can weigh-up whether the department has taken enough precautions or are required to take additional precautions, to prevent harm occurring.

What is a Hazard? A Hazard is anything that has the potential to cause harm, e.g. chemicals, electricity, working up a ladder. Using a crane, forklift …….

What is a Risk? The Risk is the likelihood that the hazard will cause harm and the severity of the consequence. For Example: If you are cleaning the oven with corrosive cleaner without using gloves or apron there is a great risk of being harmed. If you wear all protective clothing and gloves and adhere to all safety precautions the risk is low. If you change the chemical to a safer type and adhere to all precautions the risk will be even lower.

Risk Assessment In Practice 1. 2. 3. 4. 5.

Five Steps to Risk Assessment: Look for the hazards. Decide who might be harmed and how Evaluate the risks and decide whether the existing precautions are adequate or whether more should be done. Record your findings. Review your assessment and revise it if necessary.

1. Hazard Identification Walk around the workplace and look afresh at what could reasonably be expected to cause harm. Previous Accident Reports. Brainstorming Knowledge of Employees Material Safety Data Sheets (MSDS) Manufacturers Instruction Books Ask, “What If ….?”

Continue The following are examples of plant, equipment or activities that are usually associated with a hazard: Work at heights, and access to/from it (roofwork, ladders, scaffolds). Work below ground level and in confined spaces (tanks, ducts, trenches) Manual handling of loads. Work with electricity (portable tools, extension leads) Hazardous chemical substances.

Continue Display screen equipment. Ionizing, non - ionizing and laser radiation Pressure vessels / vacuum works Flammable liquid and gases Machinery and plant (machinery requiring guarding). Grinding/milling machines Woodworking machines. Portable power tools. Noise Vehicles (forklift, cranes) Disposal of special wastes.

List of Hazards Slipping/tripping hazards (poorly maintained floors or stairs). Fume (from welding) Dust (from grinding) Manual handling Poor lighting Temperature

Electricity (poor wiring) Ejection of material (from plastic moulding) Chemicals (battery acids) Pressure systems (steam boilers).

2- Who Might Be Harmed and How Generally it will be staff occupying the workplace. Attention must be paid to: Visitors Contractors Cleaning staff Maintenance staff Inexperienced staff

3- Assessment of the Risk 1. 2. 3. 4.

For the hazards listed, do the precautions already taken: Meet the standards set by the legal requirement? Comply with a recognized industry standard? Represent good practice? Reduce risk as far as reasonably practicable?

Consequences (Slightly Harmful – Harmful – Extremely Harmful)

Example – Working at Height If these three workers fell down these heights, the consequences will be different

Likelihood (Probability) Highly unlikely – Unlikely - Likely

Example – Working at Height The probability of falling off an edge is more likely the closer you are working to it

Risk Consequences X Probability Consequences Probability Highly Unlikely (1)

Slightly Harmful Harmful (1) (2)

Extremely Harmful (3)

1

2

3

Unlikely (2)

2

4

6

Likely (3)

3

6

9

4- Recording of Assessment Findings Formal written record. Any suitable form. Where the risk is considered to be low, either from experience or from the calculation of risk rating, this must be stated in the form and no further action is then required. If the risk is deemed to be medium or high, the further action needed to control that risk must be clearly stated on the risk assessment form.

Risk Control Risk Level 1

Action and Timescale No action is required and no documentary records to be kept.

2

No Additional controls are required. Consideration may be given to a more costeffective solution or improvement that imposes no additional cost burden. Monitoring is required to ensure that the controls are maintained.

3-4

Efforts should be made to reduce the risk, but the costs of prevention should be carefully measured and limited. Risk prevention measures should be implemented within a defined time period.

Risk Control 6

9

Work should not be started until the risk has been removed. Considerable resources may have to be allocated to reduce the risk. Where the risk involves work in progress, urgent action should be taken. Work should not be started or continued until the risk has been reduced. If it is not possible to reduce risk even with unlimited resources, work has to remain prohibited.

Example The task of shredding documents in a paper shredder. 1. Begin with identifying hazards: Entanglement: (being drawn into the document shredder.) Contact with moving parts Overheating leading to fire

Consequences Slightly Harmful (1) Harmful (2) Extremely Harmful (3) XXXXXX

Probability Highly Unlikely (1) XXXXXX Unlikely (2) Likely (3)

Risk Consequences X Probability Consequences Probability Highly Unlikely (1)

Slightly Harmful Harmful (1) (2)

Extremely Harmful (3)

1

2

3

Unlikely (2)

2

4

6

Likely (3)

3

6

9

Risk Control Risk Level

3

Action and Timescale Efforts should be made to reduce the risk, but the costs of prevention should be carefully measured and limited; Risk prevention measures should be implemented within a defined time period; Where the risk is associated with extremely harmful consequences, further assessment may be necessary to establish more precisely the likelihood of harm as a basis for determining the need for improved control measures.

Risk Control When a risk assessment has identified a hazard as having unacceptable risks we have to put in place control measures to eliminate the risk or reduce the risk to an acceptable level.

HIERARCHY OF CONTROL 1. 2. 3. 4. 5. 6.

Elimination Substitution Isolation Engineering Control Administrative Control Provide Personal Safety Devices.

1. Elimination The most satisfactory method of dealing with a hazard is to eliminate it. Transporting an explosive called Anfo (ammonium nitrate + diesel oil). Both are safe in isolation but when mixed they become unstable. The dangers of long distance transport can be eliminated by not mixing them until they are on site.

2- Substitution Substituting dangerous process or substance with one that is not as dangerous. Water based paints rather than those contain lead.

3- Isolation Separate or isolate the hazard from people A guard is placed over a piece of moving machinery. A fence with gate around machines.

4- Engineering Control Fixing local ventilation system to remove harmful fumes. Fixing dust collector with proper filters. Fixing proper shock absorber to reduce noise. Ilumination / A/C

5- Administration Control Modification of the likelihood of an accident happening. Reducing the number of people exposed to the danger and providing training to those people who are exposed to the hazard. Training of electricians (licensed). Danger signs, written safety systems of work.

6- Personal Protective Equipment To be considered only when all other control methods are impractical.

5- Monitoring and Review To review the assessment periodically. The introduction of new machines, substances or people into the work place may introduce new risks or change the category of an existing risk from low to medium or high. Only when there is a significant change.

Manual Handling

Workplace & Equipment

Control of Load

Control of Work Environment

Example Degreasing tank with caustic

Hazard

Caustic

Risk

Controls

Burn to skin and 1. eye Burning of internal organs after ingestion

Safe system of work detailing: Method of cleaning Disposal Emergency first aid Spillage Storage 2. Training for all operators in each of the safe systems of work detailed above and hazards and risks of using caustic.

Hazard

Risk

Controls

3. Face visor, rubber gloves, apron, overalls and safety shoes to be used. 4. Storage facilities for personal protective equipment close to operation. 5. Shower located within 100 feet of process 6. Secure storage area for caustic. Labelled with hazard warning labels. Supervisor to ensure compliance with above.

Hazard

Fork lift trucks

Example – Fork lift trucks Risk

Travelling vehicle Crushing Cuts Overturning vehicle Crushing Cuts Load type injury

Controls

1.

2. 3.

4.

Training program: All drivers to pass approved course with certificate. Regular updates To match vehicle to task. Safe working loads etc. Survey of layout of factory, to ensure correct signs, mirrors, walkways, traffic system etc. Maintenance: regular maintenance by competent mechanics to be initiated

Hazard Risk

Controls

5. Storage. Fleets to be Vehicle secured when not in use at Acid burns night. Demarcated area, Crushing security of keys, forks down etc. by forks 6. Awareness program for Carbon pedestrians: all to be made monoxide aware of dangers. poisoning 7. Daily checks and/or fault identification: “Do not use notices” to be used.

Example Every week, two workers are required to clean the public toilet blocks in the local park. To do this they take a truck, which has a small pressure pump and hose stored on the back of it. They drive the truck to the front of the toilet block, lift the pump off the truck, carry it into the toilets, attach the hose to the tap and clean the block with high pressure water. When they have finished, they carry the pump out to the truck and reload it onto the back of the truck and go to the next park with a toilet block.

Hazards The pump is heavy and awkward to lift. (Manual Handling) When they are using the hose in the toilet block the noise is too high. (Noise)

Risk Muscle strain Back injuries Hearing loss

Control Change work practices by increasing length of hose to eliminate the need to lift the pump. Change work practices by increasing lenth of hose to reduce the noise level inside the toilet block.

Hazard

Risk

Controls

Manual Muscle Strain Handling Back injuries

Change work practices by increasing length of hose to eliminate the need to lift pump.

Noise

Change work practices by increasing length of hose to reduce the noise level inside the toilet block.

Hearing loss

Control of Substances Hazardous to Health

COSHH

Guidance on the Procedure for Carrying out an Assessment in order to comply with the COSHH Regulations 1. Categorization: 1.1: Chemicals used in a laboratory or similar location. 1.2: Proprietary materials such as cleaning fluids, adhesives, paints. 1.3: Biological Agents.

Assessment of Chemicals 1. Hazard Evaluation: For the purposes of assessment all substances should be assigned one of the hazard categories listed in table 1. Substances of unknown toxicity should normally be categorized as of high or extreme hazard.

Hazard Category Extreme Hazard

Table 1 Examples Human carcinogens Respiratory sensitizers

High Hazard

Other carcinogens Volatile substances where the saturated vapor pressure (in ppm) divided by its MEL is greater than 100 but less than 1000

Medium Hazard

Volatile substances where the saturated vapor pressure (in ppm) divided by its MEL is 100 or less.

Low Hazard

Substances with OES > 500 ppm

Definition MEL : Maximum Exposure Limit OES : Occupational Exposure Standard (8hr TWA) CHIP: Chemicals Hazard Information and Packaging for supply.

2- Exposure Estimation Score

1

10

100

A Quantity of substance

Less than 1g

1-100g

More than 100 g

B Physical Dense solid, non- Dusty solids, Gases, highly volatile characteristics of volatile liquids, freeze dried solids, liquids, aerosols, substance no skin volatile liquids, low substances that are absorption skin absorption easily absorbed through the skin C characteristics Predominantly Partially open of operation enclosed system, system, low low chance of chance of mishap mishap

AXBXC

102 OR LESS

AXBXC

103 OR 104 5

6

Low exposure potential Medium exposur potential High exp. Pot.

No physical barrier, any operation where chance of mishap is medium or high (includes the dispensing of chemicals)

3- Risk Assessment The assessment of risk combines the estimates of hazard and exposure leading to an overall classification of the activity as: HIGH, MEDIUM, OR LOW RISK Table 3 can be used to classify the risk and hence the level of containment required.

Example The work to be undertaken is to determine whether a substance is soluble in diethyl ether by attempting to dissolve it in 1.5 cm3 of diethyl ether in a test tube at room temperature. The substance to be dissolved has been assessed as a low risk. Saturated Vapor Pressure (SVP) of Diethyl Ether = 400 mm Hg at 18º. Occupational Exposure Standard (OES) of Diethyl Ether = 400 ppm

Solution (SVP) in ppm = 400 x 106 = 526315 760 SVP = 526315 = 1316 OES 400 Therefore from table 1 Diethyl Ether is categorized as extreme hazard.

Exposure Estimation Using table 2, the quantity of Diethyl Ether to be used is 1.5 cm3 giving a value for A of 10 Diethyl Ether is highly volatile liquid giving a value for B of 100. Use of the test tube can be described as a partially open system with low chance of mishap giving a value for C of 10. The total score of AXBXC = 104 which gives a medium exposure potential..

Risk Assessment Using Table3 The use of substances that are categorized as being extreme hazards always requires the use of a fume cupboard which appears overcautious for the use of only 1.5 cm3 of Diethyl Ether. Since STEL of Diethyl Ether is 550 ppm to create such amount the quantity of ether needed is about 214 cm3 (100 m3 lab). In this case the use of only 1.5 cm3 would make it impossible to reach the STEL and therefore the work may carried out on the lab bench.

Control Measures – Table 4 Low Risk

Open bench work is acceptable

Medium Risk Work must be carried out in a fume cupboard High Risk

A special facility eg. A glove box should be considered.