Health and Safety

by Pete Fisher

Hazardous substances

The Control of Substances Hazardous to Health (COSHH) Regulations 2002 require managers to prevent the exposure of their staff to harmful substances or processes. Where this is not possible, then the exposure must be reduced as far as is reasonably practicable – at least below the Occupational Exposure Standards. The aim of the regulations is to produce a framework for the management of the health risks produced by harmful substances.

All of the steps required by the regulations must be in place before a substance or process may be used and before any substance can be brought into the workplace.

Risk assessment

Before an assessment can be made, all the necessary information must be gathered. This includes the details of the process, the substances to be used or produced, the place where the work is to be carried out, the exposure standards and any other information concerning the possible exposure of a person to a harmful substance.

The assessment must be suitable and sufficient to adequately control exposure. Possible sources of information include, though they are not necessarily limited to, past experience, previous records, trade standards, supplier’s material safety data sheets (MSDS), labels on containers, workplace sampling and the HSE.


A suitable and sufficient assessment is the heart of the COSHH. It is in effect a management plan, based upon sound knowledge of the substance or process to be used, which will prevent the exposure of a person to substances that could be harmful to their health. Where this is not possible, exposure must be reduced to the Occupational Exposure Standard, or lower if reasonably practicable.

A competent person must produce the assessment, which must be documented. The procedure and standardised forms should be contained in the Health and Safety Policy. It is the responsibility of the manager of the persons using or creating the substance to ensure that an assessment is carried out, that it is accurate, that it will protect workers adequately and that all of the steps required within the assessment are in place before the work commences.

The assessment, and compliance with it, is important, as it enables employers to demonstrate that all factors have been considered, that they have adequate knowledge on which to base control measures and that they can show continuity of effort and achievement in dealing with health risks associated with the work.

Production of the supplier’s MSDS on its own does not constitute an assessment under the regulations.

Control measures

If an assessment details any specific control measures, such as the use of an extraction system or personal protective equipment, any provisions must be followed by the employee and equipment regularly inspected and maintained.

If monitoring is required to ensure that adequate control is being achieved, a sampling regime will be required, which should be designed by a qualified occupational hygienist.

Records must be kept of maintenance, tests and inspections, and mechanical extraction systems must be thoroughly examined by a competent person every 14 months.

Health surveillance

In some circumstances, particularly where work involves the use of specified substances, such as lead and asbestos, it may be appropriate to implement health surveillance for employees. The advice of an occupational hygienist must be sought to ensure the correct procedures are followed.

Information, instruction and training

Employees working with or exposed to harmful substances must be provided with relevant and understandable information, instruction and training so that they know the risks to their health and the steps required to prevent or control it.

The information should include the actions to take in the event of an emergency and the correct means of disposing of the waste products.


All hazardous substances must be stored in appropriate cupboards or other specialised stores (unless the risks and quantities are low), following

  • The manufacturer’s instructions
  • The findings of the COSHH assessment
  • Any local or business requirements.

When setting up storage arrangements, it is necessary to consider compatibility of the substances to be stored in the same place, should they come into contact with one another, plus the risk that they may contaminate other items in the store.

Other factors are

  • Unauthorised use
  • Danger to others from fumes or vapours
  • Fire risk from flammable substance
  • Security – particularly where there may be a risk of children gaining access.