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COSHH Assessments

It is now illegal to use hazardous substances at work if a COSHH assessment has not been carried out (Control of Substances Hazardous to Health Regulations 1999). In all but the simplest situations, a written assessment will be needed.

The following stages are involved:

1. List all hazardous substances

Make an Inventory of all hazardous substances stored, used or produced by your work. This should list what is stored or produced, in what form, in what quantities and where.
Look for Hazard Symbols which classify the substance as Very Toxic, Toxic, Corrosive. Harmful or Irritant. Check up on unmarked or unclearly marked containers which you suspect may contain hazardous contents.
Include dusts, fumes or by-products which have Exposure Limits set in EH40.

2. Find out more about their hazardous nature

Obtain Hazard Data Sheets from product suppliers. These will provide more information on the products hazards, conditions of use and some emergency advice.

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3. How are these substances used?

Examine the work process carefully. Some areas you may need to look at are: Delivery and storage; Preparation and use; Other activities taking place nearby (e.g. cleaning, maintenance, eating, smoking, etc); Disposal of residues and containers; Unplanned events and emergencies.

4. What are the risks of injury or ill-health?

From your knowledge of the substance, the work process and foreseeable emergencies decide what the chances are of somebody being injured or suffering from health effects and how this could occur. Only significant risks need be considered.
Risks could arise from a number of sources, for example: spillage's and splashes; mixing incompatible substances; breathing dusts and vapours; absorption through skin contact with the substance; accidental ingestion.
Consider who is at risk. Include third parties such as visitors, public and contractors on your premises in addition to your staff. The length of exposure is also important.

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5. Decide on the precautions needed

The easiest way to remove the risk from a hazardous substance is to stop using it altogether (elimination) or replace it with another less harmful product (substitution).
Thereafter, consider removing those at risk from the substance (enclosure and isolation) or extracting the dusts and fumes from the work area (dilution and local exhaust ventilation).
As an absolute LAST RESORT direct protection of the worker should be considered (personal protective equipment).
All these precautions are known as Controls and you must ensure that they are being used properly and monitor and maintain their effectiveness. In some cases, health surveillance must be considered, but this is only in special cases.

6. Record your assessment

Unless the assessment is simple and you can recall and explain its conclusion at any time, you should put it in writing. The assessment should clearly lay out who is at risk and why, and what precautions are in place to reduce the risks to a reasonable level.

7. Instruct and train your staff

Staff need to be told about the hazardous nature of the substances they are working with and any risks to which they may be exposed.
Instruction and training must be given on any precautions which must be taken; control measures and their correct use; and what personal protective equipment and clothing is needed and how it should be properly used.
Training on Emergency Procedures must also be given to staff.
Remember to keep records on who has been trained and when.

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8. Review your assessment

You need to review the assessment on a regular basis (not less than 5 yearly intervals). The assessment must also be reviewed if there is a change in product or process. The assessment should state when it is to be reviewed next.

Further information

Occupational Exposure Limits (EH40/2000) ISBN 0 7176 0722 4; COSHH: A brief guide to employers (IND(G)136L); COSHH Assessments - A step by step guide ISBN 0 11 886379 7; COSHH and peripatetic workers (HS(G)77) ISBN 0 11885733 9; COSHH; An open learning course ISBN 0 7176 0850 6.

Other Hazardous Substances:

There are other hazardous substances that do not come under COSHH, but still need to be assessed. These include: Flammable and Explosive substances; Substances at High and Low Temperature; Radioactive substances; and Asbestos. Specific guidance is available on these hazards and specific legislaton may apply. Pesticides come under the COSHH Regulations, but are also governed by other legal requirements. For more information on these areas, telephone 01244 324324 and ask for the Health and Safety Team.

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Advice Sheet 4: COSHH Assessments

A copy of this advice sheet is available to download in the following formats:

Advice Sheet 4: COSHH Assessments - MS Word format 44Kb

Advice Sheet 4: COSHH Assessments - PDF format 77Kb

Advice Sheet 4: COSHH Assessments - Plain Text format 136Kb

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