The Control of Substances Hazardous to Health (COSHH) Regulations cover substances that have the potential to harm health

Employers must risk assess all substances and prevent exposure of workers to substances that harm their health at work

If substances are harmful to health then employers must use the COSHH Control Hierarchy to remove or control them. They must:

  • Identify all substances used at, or arising in the course of, work– dust, fumes, gases, combustion & by-products

  • Safety reps should ask your employer to carry our air monitoring – what’s in the air, how much and what size particles. see the case study on air pollution for more information

  • Assess their risks, and if they are hazardous to health - in short or long term e.g. carcinogenic, irritant, corrosive, asthmagenic, mutagenic, reproductive toxins, then employers must:

Eliminate or substitute with safer substances.

Intelligent Substitution based on hazards of class of chemicals – check what new risks could be created TURI -

If this is not possible, then:

Use engineering & other controls to prevent exposure of all workers—isolate, enclose, local exhaust ventilation - and

Only as a last resort use Personal Protective Equipment - this is because it is an individual protection and the rest are collective protections and preventions at source. The employer is responsible for the maintenance, storage and replacement of any PPE they provide. As a worker, you are required to use the PPE properly following training and instruction from your employer. If the PPE you provide is lost or becomes defective, you should report that to your employer.

See previous section in 'what does the law say' for more information

Concentrate on eliminating or controlling the most hazardous substances first - MERCS (mutagens, endocrine disrupting chemicals, carcinogens, reproductive toxins, carcinogens)

  • Mutagens (cause changes to genes);

  • Endocrine Disrupting Chemicals (cause changes to hormone controlled processes);

  • Reproductive toxins (causes harm to eggs, sperm, reproductive system and the foetus)

  • Carcinogens (cause cancer)

•The more we learn about these substances/chemicals, the more we find even small exposures of previously thought safe substances can be harmful, especially for children & developing foetus.

•Many toxic substances have synergistic, additive, cumulative & chronic effects

•It makes sense to reduce our exposure to all substances as far as we can- Use the Precautionary Principle (The precautionary principle should be invoked when:

— there is good reason to believe that harmful effects may occur to human, animal or plant health or to the environment; and

— the level of scientific uncertainty about the consequences or likelihood of the risk is such that the best available scientific advice cannot assess the risk with sufficient confidence to inform decision-making. )

•For example, identify and eliminate all cleaning chemicals that contain hazardous substances with warning signs, WELs (work exposure limits), known risks

•Work with union & employer on Toxics Use Reduction programme. - see separate section

•Only completely safe level of a chemical is ZERO exposure

•UK WELs - Work Exposure Limits NOT Safe Levels of exposure; No safe level of exposure to carcinogens, or PM2.5, or Endocrine Disruptive Chemicals No hazard: No harm

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