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COSHH Assessment Procedure

Introduction

The Department of Engineering (CUED) must ensure that exposure to substances hazardous to health is either prevented or adequately controlled.

In order to comply with the Control of Substances Hazardous to Health (COSHH) Regulations CUED must make an assessment of the health risks created in the workplace by hazardous substances and the measures that are needed to control these.

This procedure applies to all work materials hazardous to health within CUED.  They include recognised hazard classifications such as toxic, harmful, corrosive, sensitiser, irritant, carcinogen, mutagen and toxic to reproduction.  Biological hazards are classified according to their potential and ability to cause infection and harm.

Responsibilities

Supervisors must ensure that COSHH assessments have been carried out for all work processes involving hazardous materials and that these are readily accessible at the workplace.

Supervisors must provide their staff, researchers and visitors with suitable information, instruction and training about:

  • the nature of the substances they work with, or are exposed to, and the risks created by exposure to these substances
  • the precautions they should take
  • control measures, their purpose and how to use them
  • how to use personal protective equipment and clothing provided
  • emergency procedures.

Users must be informed of the findings of relevant COSHH assessments by the assessor including the results of any exposure monitoring and health surveillance.

Supervisors must ensure that those using chemicals are familiar with CUED safety procedures, particularly Laboratory, Chemical and Biological Safety and Waste Disposal.

COSHH Assessment Form

To assess the risk from hazardous substances a COSHH Assessment Form must be completed which should include the following areas:

Assessor and Supervisor information

The Assessor (the one writing the risk assessment) and the Supervisor should be properly identified.  Contact details should be included for the Assessor.

Location

Identify the room(s), building(s) and sites(s) where this procedure is undertaken.

Assessment Reference

A unique reference number is assigned by the Safety Office.

Procedure

Write a short description of the procedure or task.  Include recipes for reagents, buffers, solvents etc. that contain more than one chemical.

Chemical

Write the full chemical name as identified on the Material Safety Data Sheet (MSDS). Include CAS number if likely to be confused with other chemicals.  If a commercial product, write commercial name followed by chemical constituents.  If relevant to the hazard, list concentration of chemical (e,g. an acid may be corrosive, irritant or non-hazardous depending upon concentration).

Hazard

Use the risk phrases from the MSDS e.g. Irritating to eyes, respiratory system and skin. Ecological information (e.g. toxic to aquatic organisms) need not be included but will inform your choice of disposal.

Biological hazards

Use scientific name of organism/agent wherever possible, together with common or commercial name if appropriate.  For biological hazards, list ACDP hazard category.

Other hazards may include information on e.g. flammability, radiation safety, heat, cold and sharps.

Workplace Exposure Limits

Workplace Exposure Limits (WELs) are occupational exposure limits designed to help protect the health of workers.  WELS are concentrations of hazardous substances in the air, averaged over a specified period of time referred to as a time-weighted average.  Two time periods are used: long-term (8 hours) and short-term (15 minutes).  Short-term exposure limits are designed to reduce effects such as eye irritation that may occur following exposure for a few minutes.

Control measures

When controlling exposure to a hazardous substance consider whether:

  • the process can be changed to eliminate the need for the substance,
  • the substance can be replaced with a safer alternative,         
  • the substance can be used in a safer form e.g. pellets instead of powder, ready made buffers or gels etc.

If prevention is not reasonably practicable, you must adequately control exposure e.g. by one or more of the following:

  • totally enclose the process (e.g. glove box),
  • partially enclose the process (e.g. fume cupboard),
  • improve general ventilation,
  • use systems of work that minimize the chances of spillage etc.,
  • reduce the number of persons exposed.

List all engineering measures appropriate for the control of exposure to the hazard.  This should be indicated by the MSDS and the risk phrase (e.g. if toxic by inhalation then use in a fume cupboard).  Fume cupboard, glove box, safety cabinet (for biological) and local exhaust ventilation are examples.

The nature of the hazard will influence the control measures required.  These are summarised here.

Fume cupboards and safety cabinets

When reliance is placed upon local exhaust ventilation, fume cupboards and other equipment, it is essential that they are tested at least annually and test records are kept for a minimum of five years.  Record testing frequency and by whom.  Any control measures must be maintained in an efficient working order and work as intended.  Reduced efficiency must be detected.  All engineering controls should be visually checked at least once a week and be subject to preventative service procedures.

Adverse results from periodic test of control measures will necessitate review of any existing assessment(s).

Local management (e.g. Chief Technician) is responsible for the preventative maintenance of engineering controls within their area and for retaining records.  The Safety Office can advise on and arrange maintenance and testing.

Flammables and explosives

The Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR) set out minimum requirements for the protection of workers from fire and explosion from dangerous substances and potentially explosive atmospheres.

DSEAR applies where there is present any substance or mixture of substances with the potential to create a risk from energetic (energy-releasing) events such as fire, explosions, thermal runaway from exothermic reactions etc. Such substances, known in DSEAR as dangerous substances, include:

  • flammable substances
  • oxidisers
  • explosives
  • petrol
  • liquefied petroleum gas (LPG)
  • paints and varnishes
  • solvents
  • certain types of dust that are explosive (e.g. wood dust)

 

The main requirements of DSEAR are that:

  • an assessment is made of the fire and explosion risks of any work activities involving dangerous substances
  • measures are undertaken to eliminate, or reduce as far as is reasonably practicable the identified fire and explosion risks
  • residual risks are controlled in order to mitigate the detrimental effects of a fire or explosion
  • equipment is provided and procedures put in place to deal with accidents and emergencies
  • information and precautionary training given

 

Additionally, where explosive atmospheres may occur, signage should indicate the hazardous area and equipment within that area should satisfy The Equipment and Protective Systems Intended for Use in Potentially Explosive Atmospheres Regulations 1996.  Classification of a work area should be by a competent person (contact Safety Office).

Personal Protective Equipment

Record type of protective equipment used.  Personal protective equipment (PPE) should only be used where it is not practical or feasible to achieve adequate control by operational or engineering measures alone, in an emergency or for routine maintenance.  PPE should comply with International, European or British Standards.

Eye protection would be indicated for most hazardous chemicals, a face shield or goggles for corrosives and chemicals with the risk phrase ‘risk of serious damage to eyes’.

Respiratory protection such as dust masks will require face-fit testing (contact Safety Office).

Many chemicals can permeate glove materials (especially organic solvents).  Check ‘breakthrough times’ published by manufacturers and suppliers.

Monitoring

Where necessary, monitoring of the work place should be undertaken to ensure that exposure to hazardous substances is below permitted exposure limits.  If the risk assessment has identified that these limits may be exceeded if control measures fail, then monitoring must be carried out e.g. low oxygen alarms in areas using liquid nitrogen or carbon monoxide alarms for combustion experiments.

Health Surveillance

For work involving:

  • category 1 and 2 carcinogens, mutagens and substances toxic to reproduction (refer to Cambridge List)
  • respiratory or skin sensitisers
  • pathogens or biological agents in Hazard Group 3 or above
  • orgnophosphorus compounds
  • mercury or mercury compounds (where exposure to vapour or dust is possible)
  • cadmium or cadmium compounds (where exposure to vapour or dust is possible)
  • burning lead (e.g. welding or soldering)
  • free nanoparticles

Notification will be given to Occupational Health and those working with them should complete a health record and submit it to the Safety Office annually.  These records must be kept by the Department for 40 years to comply with the COSHH Regulations.

Storage

Certain substances may require particular storage because of flammability, incompatibility or other hazard.  Incompatibilities are generally listed on the Hazard Data Sheet.

Waste Disposal

The assessment must include the appropriate safe disposal of reagents after completion of a procedure.

Emergency procedures

Consider possible emergencies such as the dropping of stock bottles or concentrated solutions.

First aid

List relevant first aid procedures.

Out of hours/lone working

The consequences of accidental exposure will be greater if working alone or out of hours.  Consider whether the procedure or parts of the procedure are appropriate for lone working (see Lone Working for further guidance).  Note any enhanced control measures required for out of hours or lone working.

Assessment Summary

Summarise the assessment, highlight any areas of concern and identify any groups at enhanced risk (e.g. exposure of new and expectant mothers to certain compounds).

List any necessary additional measures required.

If the risk to health and safety is assessed as high, the procedure must be suspended until additional measures are in place.

Assessor

The assessor should have experience of the procedure being assessed and sign to confirm and agree to the results of the assessment.

Supervisor

The responsibility for approving the assessment is with the Principal Investigator (Supervisor).  The Supervisor is signing to acknowledge the competence of the assessor and that they have had suitable and sufficient training to do the task safely.

If a procedure has been assessed by one group but applies equally to another, then subsequent Supervisors should counter-sign a copy..

Example assessment

A filled example form can be found here.

Hazard assessment

A COSHH assessment must identify the hazardous substances in the workplace.   The hazard a substance presents is dependent upon the type of hazard (e.g. toxic, irritant, sensitiser etc.), the route of exposure (e.g. inhalation), the amount being used and its physical form.

Hazard data sheet

Health and Safety information for substances used or held by CUED can be found on the relevant Material Safety Data Sheet as issued by the supplier.

Hazard group

For risk assessment purposes, hazardous substances can be placed into hazard groups corresponding to their assigned risk number(s) and its associated risk phrase(s).  This will also indicate the route of exposure.  Suggested hazard groups can be found below.

Biological hazards are classified according to ACDP guidelines (see here).

Amount

For CUED laboratory procedures, the amount of chemical used can be classified as small (mg or μl), medium (g or ml) or large (kg or litre).  Remember that the largest amount handled would generally be the stock bottle.

Physical form

The physical form of a chemical will affect how likely it is to get into the air.

For solids, dustiness is the key property.  Degree of dustiness may be classified as low (pellets, flakes etc.); medium (crystalline, granular); high (fine, light powders).

For liquids, volatility is the key property.  This is generally related to boiling point i.e. for tasks carried out at room temperature:

  • boiling point below 50ºC, high volatility       
  • between 50ºC and 150ºC, medium volatility
  • above 150ºC, low volatility

For tasks carried out above room temperature, volatility will increase.

 

Hazard groups

 

Exposure by inhalation

 

Group A – low/no hazard

H303 - May be harmful if swallowed

H313 - May be harmful in contact with skin

H315 - R38 - Causes skin irritation

H316 - Causes mild skin irritation

H320 - R36 - Causes eye irritation

Group B – moderate hazard

H302 - R22 - Harmful if swallowed

H305 - May be harmful if swallowed and enters airways

H313 - R21 - Harmful in contact with skin

H319 - Causes serious eye irritation

H332 - R20 - Harmful if inhaled

H333 - May be harmful if inhaled

H335 - May cause respiratory irritation

H336 - May cause drowsiness or dizziness

H371 - May cause damage to organs

H373 - May cause damage to organs through prolonged or repeated exposure

Group C – high hazard

H301 - R25 - Toxic if swallowed

H311 - R24 - Toxic in contact with skin

H314 - R35 - Causes severe skin burns and eye damage

H317 - R43 - May cause an allergic skin reaction

H318 - Causes serious eye damage

H331 - R23 - Toxic if inhaled

H370 - Causes damage to organs

H372 - Causes damage to organs through prolonged or repeated exposure

Group D – very high hazard

H300 - R28 - Fatal if swallowed

H304 - May be fatal if swallowed and enters airway

H310 - R27 - Fatal in contact with skin

H330 - R26 - Fatal if inhaled

H334 - May cause allergy or asthma symptoms or breathing difficulties if inhaled

H360 - R60/61 - May damage fertility or the unborn child

H361 - R62/63 - Suspected of damaging fertility or the unborn child

H362 - May cause harm to breast-fed children

Group E – Special Hazard

H340 - R40/46 - May cause genetic effects

H341 - Suspected of causing genetic effects

H350 - R45 - May cause cancer

H351 - Suspected of causing cancer

 

Control approach

 

Amount Used

Low dustiness or volatility

Medium volatility

Medium dustiness

High dustiness or volatility

Hazard group A

Small

1

1

1

1

Medium

1

1

1

1

Large

1

1

1

2

Hazard group B

Small

1

1

1

1

Medium

1

1

1

2

Large

1

1

2

2

Hazard group C

Small

1

2

1

2

Medium

1

2

2

2

Large

2

3

3

3

Hazard group D

Small

2

3

2

3

Medium

2

3

4

4

Large

3

4

4

4

Hazard group E

For all hazard group E substances, choose control approach 4


Key

Control approach 1             =     general ventilation sufficient

Control approach 2             =     fume cupboard

Control approach 3             =     requires containment

Control approach 4             =     prohibited or requires special instruction, see Safety Office

For CUED laboratory procedures, the amount of chemical used can be classified as small (mg or μl), medium (g or ml) or large (kg or litre).  Remember that the largest amount handled would generally be the stock bottle.


Exposure to skin or eyes

Group S

Low hazard

H313 - May be harmful in contact with skin

H315 - R38 - Causes skin irritation

H316 - Causes mild skin irritation

Moderate hazard

H313 - R21 - Harmful in contact with skin

H320 - R36 - Causes eye irritation

High hazard

H311 - R24 - Toxic in contact with skin

H314 - R35 - Causes severe skin burns and eye damage

H370 - Causes damage to organs

H372 - Causes damage to organs through prolonged or repeated exposure

Very high hazard

H310 - R27 - Fatal in contact with skin

H314 - R35 - Causes severe skin burns and eye damage

H317 - R43 - May cause an allergic skin reaction

H318 - Causes serious eye damage

For combinations of risk phrases, assign to higher hazard group.

All chemicals in Group S require laboratory coat, appropriate gloves and safety specs.

 

Flammables and Explosives

H200 - Unstable explosive

H201 - Explosive; mass explosion hazard

H202 - Explosive; severe projection hazard

H203 - Explosive; fire, blast or projection hazard

H204 - Fire or projection hazard

H205 - May mass explode in fire

H220 - Extremely flammable gas

H221 - Flammable gas

H222 - Extremely flammable aerosol

H223 - Flammable aerosol

H224 - Extremely flammable liquid and vapour

H225 - Highly flammable liquid and vapour

H226 - Flammable liquid and vapour

H227 - Combustible liquid

H228 - Flammable solid

H240 - Heating may cause an explosion

H241 - Heating may cause a fire or explosion

H242 - Heating may cause a fire

H250 - Catches fire spontaneously if exposed to air

H251 - Self-heating; may catch fire

H252 - Self-heating in large quantities; may catch fire

H260 - In contact with water releases flammable gases which may ignite spontaneously

H261 - In contact with water release flammable gas

H270 - May cause or intensify fire; oxidizer

H271 - May causee fire or explosion; strong oxidizer


Advisory Committee on Dangerous Pathogens Categorisation of Biological Hazards

 

Group 1

Unlikely to cause human disease.

Group 2

Can cause human disease and may be a hazard to employees; unlikely to spread to the community; effective prophylaxis or treatment available.

Group 3

Can cause severe human disease and may be a serious hazard to employees; may spread to the community; effective prophylaxis or treatment usually available.

Group 4

Causes severe human disease and is a serious hazard to employees; likely to spread to the community; no effective prophylaxis or treatment available.