COSHH 2002: HSE Hazardous Substances Rules

Regulatory citation: Control of Substances Hazardous to Health Regulations 2002 (SI 2002/2677)

What Are the COSHH Regulations?

The Control of Substances Hazardous to Health Regulations 2002 (COSHH) require employers in Great Britain to control exposure to hazardous substances to prevent ill health. Hazardous substances include chemicals, fumes, dusts, vapors, mists, gases and biological agents, as well as substances generated by work such as wood dust or welding fume.

Why COSHH Matters

Exposure to hazardous substances can cause asthma, dermatitis, cancer and other serious diseases, often years after exposure. COSHH provides a structured approach to preventing that harm.

Core Requirements

1. Assess the Risks

Employers must assess the risks to health from hazardous substances before work begins and decide what precautions are needed.

2. Prevent or Adequately Control Exposure

Exposure must be prevented, or where that's not reasonably practicable, adequately controlled, following the principles of good practice, with personal protective equipment used as a last resort.

3. Comply With Workplace Exposure Limits

Where a substance has a workplace exposure limit (WEL), listed in HSE's EH40 publication, exposure must not exceed it. Exposure to carcinogens, mutagens and asthmagens must be reduced to as low as reasonably practicable.

4. Maintain and Test Controls

Control measures must be maintained in efficient working order. Local exhaust ventilation (LEV) must be thoroughly examined and tested at least every 14 months in most cases, with some processes requiring more frequent checks.

5. Monitor Exposure and Provide Health Surveillance

Exposure monitoring is required in certain cases, and health surveillance must be provided where workers are exposed to substances linked to identifiable diseases.

6. Plan for Emergencies and Train Workers

Employers must have plans for accidents and emergencies involving hazardous substances, and give workers information, instruction and training.

Common Compliance Approaches

Use Safety Data Sheets

Safety data sheets provide key hazard and control information, but assessments must reflect how substances are actually used.

Look for Substitutes

Replace hazardous substances with less harmful alternatives, or use less hazardous forms such as pastes instead of powders.

Check LEV Is Working

Use airflow indicators and routine checks between thorough examinations.

Example: COSHH in Practice

A joinery workshop identifies hardwood dust, a known cause of asthma and nasal cancer, as a key hazard. It installs LEV on its saws and sanders, sets up a cleaning regime using an industrial vacuum instead of sweeping, provides face-fit tested respirators for high-dust tasks, arranges health surveillance for respiratory symptoms, and books LEV thorough examinations every 14 months.

Related regulations: MHSWR risk assessments, OSHA HazCom, OSHA Respiratory Protection.

Note: This summary reflects the regulations as they apply in Great Britain, enforced by the Health and Safety Executive (HSE) and local authorities. Northern Ireland has equivalent but separate legislation. Always check the current legislation and HSE guidance.

Frequently Asked Questions

What is a COSHH assessment?

A COSHH assessment identifies the hazardous substances used or produced at work, who could be harmed and how, and the control measures needed to prevent or adequately control exposure. It must be reviewed regularly and when circumstances change.

How often must LEV be tested under COSHH?

Local exhaust ventilation must generally be thoroughly examined and tested at least once every 14 months, with some processes, such as certain abrasive blasting or polishing activities, needing more frequent examinations.

What are workplace exposure limits?

Workplace exposure limits (WELs) are legal limits on airborne concentrations of hazardous substances, averaged over a set period. They are published in HSE's EH40 document.