COSHH Assessment Records: What UK Employers Must Keep

The Control of Substances Hazardous to Health Regulations 2002 — universally known as COSHH — require employers to assess and control the risks from hazardous substances in the workplace. Crucially, they also require that those assessments and the controls arising from them are recorded and maintained. COSHH record-keeping is one of the most frequently cited failures in HSE inspections across industries from construction to healthcare, manufacturing to catering.

What Is a COSHH Assessment?

A COSHH assessment is a systematic examination of the substances hazardous to health that employees may be exposed to at work, the risks they present, and the controls needed to prevent or adequately control that exposure. Under Regulation 6 of COSHH, employers must not carry out work that is liable to expose employees to substances hazardous to health unless they have made a suitable and sufficient assessment of the risks and the steps needed to meet the requirements of the regulations.

Substances hazardous to health include chemicals, fumes, dusts, vapours, mists, gases, biological agents, and nanotechnology materials. If a substance has a hazard warning on the label — flammable, toxic, corrosive, harmful — it requires a COSHH assessment before use.

What Records Must Be Kept?

Where the employer has five or more employees, COSHH assessments must be recorded in writing. The record must document the substances identified, the nature and degree of exposure, the persons affected, the existing controls and their effectiveness, any additional controls required, the conclusions of the assessment, and the date of the assessment and the name of the person who carried it out.

Safety data sheets — supplied by the manufacturer or importer of a hazardous substance under the REACH Regulations — must be obtained for all hazardous substances and retained on site. They must be accessible to workers and updated when new versions are issued. Safety data sheets alone do not constitute a COSHH assessment, but they form the evidential basis for one.

Where exposure monitoring is required — for substances with Workplace Exposure Limits set by the HSE — monitoring records must be kept for at least five years. Where the substance may cause ill health with a long latency period, such as carcinogens, the monitoring records must be kept for 40 years.

Health Surveillance Records

Where COSHH requires health surveillance — typically for substances known to cause occupational disease such as occupational asthma, dermatitis, or hearing damage — records of health surveillance must be maintained for at least 40 years. Health surveillance records must be kept in a confidential format and must not be disclosed to other employees without the individual's consent.

Health surveillance records must include the employee's identity, the date of surveillance, the outcome, and any action taken. They must be made available to the employee on request.

What Is a COSHH Register?

Many organisations maintain a COSHH register — a centralised inventory of all hazardous substances used in the workplace, linked to their safety data sheets and COSHH assessments. The register provides an at-a-glance overview of all hazardous substances on site and ensures that assessments are reviewed when new substances are introduced or existing ones are changed.

A COSHH register should be maintained as a live document — not compiled once and forgotten. Whenever a new substance is brought onto site, an assessment must be completed and added to the register before the substance is used.

How Often Must COSHH Assessments Be Reviewed?

COSHH assessments must be reviewed regularly and whenever there is reason to believe they are no longer valid. Triggers for review include a change in the substances used, a change in the quantities used or the method of use, new information about a substance's health effects, a change in the persons exposed or the duration of exposure, and any incident or near miss involving a hazardous substance.

Best practice is to review all COSHH assessments at least annually and to document that the review has taken place, even if no changes are required. A dated signature confirming the assessment remains valid is sufficient for routine reviews.

Frequently Asked Questions

Does COSHH apply to cleaning products? Yes. Many common cleaning products contain substances hazardous to health — bleach, solvents, descalers, and similar products. Employers must carry out COSHH assessments for all cleaning products used by their employees.

Who can carry out a COSHH assessment? A COSHH assessment must be carried out by a competent person — someone with sufficient knowledge, training, and experience to understand the risks from the substances involved and the appropriate control measures. For straightforward substances with good safety data sheets, a trained line manager or health and safety officer can carry out assessments. For complex substances or unusual exposure routes, specialist advice may be needed.

What happens if a COSHH assessment is missing during an HSE inspection? Missing COSHH assessments are a breach of Regulation 6 of COSHH and can result in improvement notices, prohibition notices, or prosecution. The HSE does not need to demonstrate that harm has occurred — the absence of a required assessment is itself an offence.

Can COSHH records be kept digitally? Yes. Digital COSHH records are entirely acceptable provided they are accessible to relevant persons, secure against unauthorised alteration, and can be produced in hard copy on request.

Key Takeaways

• COSHH assessments must be recorded in writing where five or more employees are employed — the absence of written records is itself a breach of the regulations.
• Safety data sheets must be obtained for all hazardous substances and retained on site — accessible to workers at all times.
• Exposure monitoring records must be kept for at least five years — or 40 years for substances with long latency periods.
• Health surveillance records must be kept for 40 years and maintained confidentially.
• A COSHH register provides a centralised inventory of all hazardous substances and their assessments — it must be kept up to date as new substances are introduced.
• Assessments must be reviewed regularly and whenever there is a change in substances, exposure, or personnel.