Hazardous substances

Every year exposure to hazardous substances at work affects the health of many thousands of people. Common examples include:

  • Asthma as a result of developing allergy to substances used at work
  • Losing consciousness as a result of being overcome by toxic fumes
  • Cancer, which may appear long after the exposure to the chemical that caused it
  • Infection from bacteria and other micro-organisms (biological agents)

Illness due to hazardous substances can lead to loss of earnings and disability for the person affected, and loss of productivity, prosecution, proceedings under civil law and raised insurance costs for the employer.

What legislation applies to hazardous substances?

The Control of Substances Hazardous to Health Regulations 2002 - usually referred to by the abbreviation COSHH - were introduced to protect people in the workplace from health risks associated with hazardous substances.

What do the Regulations require employers to do?

To summarise, you should first assess the risks, and then decide if they can be prevented by using a different substance or method. If not, the risks will need to be controlled and reduced by introducing various control measures. It is also a requirement to make sure that the control measures are actually used!

If you employ 5 or more people in your business you must record your risk assessment in writing.

There are some other duties that may apply, such as carrying out monitoring and health surveillance for certain employees, and providing employees with information and training on the risks and precautions.

You must also remember to consider anyone who is not an employee, but who may be affected by hazardous substances - such as visitors, contractors and the people living near to your premises.

Download working with substances hazardous to health: A brief guide to COSHH leaflet from the HSE website, which is aimed at employers in small businesses.

Do the Regulations apply to all substances, or just chemicals?

COSHH applies to virtually all substances with the potential to be hazardous to health. Exceptions include asbestos and lead (which have their own regulations) and substances which are hazardous only because they are radioactive, asphyxiants, at high pressure / temperature or have explosive / flammable properties.

This means that all sorts of apparently ordinary things are included, such as wood dust, spices and food ingredients and typing correction fluid!

Can't I just give all my employees some protective equipment, such as gloves and masks?

This may be necessary but should be regarded as a "last resort" only when exposure cannot be controlled by another method. Other control measures include replacing the substance with something safer, or changing the process to reduce the risk. Alternatively it may be possible to totally enclose the hazardous area or install local exhaust ventilation to extract the substance from the air.

I have got data sheets for all our chemicals from the manufacturers - surely I am complying with the Regulations?

This is not enough to comply - the data sheet is a very useful source of information when you are carrying out a risk assessment (or in the case of an accident) but you need to be considering how many people are exposed to potential harm, what exactly is done with the substance, how long is it used for each day, etc.

It may be acceptable just to have data sheets available if products are not handled or used (such as when they are stocked in a shop) if the only exposure would be where a bottle or container was to break. Even so, if you can foresee an emergency like this happening and the product is hazardous, you should do a risk assessment.

What about employees - do they have to do anything?

Yes, they must follow any safe systems of work that you introduce and use any control measures correctly, reporting any defects or problems to you. They must also comply with any health surveillance programmes in place, although the employer must ensure there is no cost incurred by the employee in doing so.

COSHH guidance

Go to COSHH e-tool on the HSE website and input the details of substances for an example assessment.

COSHH on the HSE website provides practical advice and Guidance on the Control of Substances Hazardous to Health Regulations 2002.

Advice and help on hazardous substances in the workplace

Environmental Health Officers can also advise and help you if you need help with a matter relating to hazardous substances in the workplace. Please contact the Food, Health and Safety Team.

Advice and help on pollution / environmental matters

If you need help with a pollution or environmental problem, please contact the Environmental Protection Team.

Last updated: Wednesday, 24 April, 2024.