What is COSHH?
COSHH is the Control of Substances Hazardous to Health Regulations 2002. They require an employer to assess the health risk from hazardous substances the work uses or creates, to prevent exposure where that is reasonably practicable and adequately control it where it is not, and, where the employer has five or more employees, to record the significant findings of that assessment.
Hazardous substance is wider than the drum with a label on it. It takes in the dust and fume the work generates rather than buys: silica, wood dust, welding fume. Those are usually the exposures that cause harm, and the ones missing from the assessment. This page is general buyer education, not legal advice.
- COSHH covers substances used at work and substances the work creates - dust, fume, mist, vapour, gas and biological agents.
- The recording duty in regulation 6(4) applies where the employer has five or more employees. The assessment itself is required regardless.
- Prevention comes first. PPE and RPE come last, only where other measures cannot adequately control exposure.
- Lead and asbestos sit outside COSHH, as do substances hazardous solely by radioactivity, flammability, temperature or pressure.
- Local exhaust ventilation must be thoroughly examined and tested at least every 14 months, and more often for Schedule 4 processes.
What COSHH covers, and what it does not
Regulation 5 sets the boundaries. COSHH does not apply where the Control of Lead at Work Regulations 2002 or the Control of Asbestos Regulations 2012 apply, and it does not apply to a substance hazardous solely because it is radioactive, explosive or flammable, or solely because it is at high or low temperature or high pressure. Those hazards fall under other regimes rather than being ignored.
Everything else that harms health by inhalation, ingestion or skin contact is in scope:
- Chemicals bought as products - solvents, adhesives, resins, cleaning agents, cement
- Dust and fume generated by the process - silica, wood dust, welding fume
- Mists, vapours, gases and biological agents
The assessment and the five-employee threshold
Regulation 6 requires a suitable and sufficient assessment of the health risk before work starts, together with the steps needed to meet regulation 7. The recording duty is worth getting right, because it is misquoted constantly: regulation 6(4) requires an employer who employs five or more employees to record the significant findings as soon as is practicable after the assessment is made, and the steps taken to meet regulation 7.
Below five employees the assessment still has to be made and acted on. Only the duty to write it down changes, and most contractors write it down anyway.
Control: prevention first, PPE last
Regulation 7 sets the order. Prevent exposure where reasonably practicable, preferably by replacing the substance or process with one that reduces the risk. Where prevention is not reasonably practicable, control exposure adequately by applying, in this order:
- Appropriate work processes, systems and engineering controls, and suitable equipment and materials
- Control of exposure at source, including adequate ventilation and organisational measures
- Personal protective equipment, only where adequate control cannot be achieved by other means
Control counts as adequate only where the principles of good control practice in Schedule 2A are applied, any workplace exposure limit is not exceeded, and exposure to carcinogens, mutagens and asthmagens is reduced as low as is reasonably practicable. Limits are published by HSE in EH40.
What COSHH does to a PPE order
It makes it specific. That is the practical consequence for anyone buying gloves, respirators or coveralls.
- The assessment names a substance. The glove is selected against that substance and a breakthrough time longer than the task, from section 8 of the safety data sheet. Chemical gloves is not a specification.
- Filters are selected against the contaminant. Particle filters offer no protection against vapours, so an FFP3 on a solvent job protects nobody.
- Tight-fitting RPE only achieves its rating on a face it seals against, so face fit testing is per person and per model.
- Where facial hair cannot be removed, the answer is loose-fitting powered RPE.
Records, maintenance and health surveillance
COSHH paperwork outlives the project, which is why a buyer asking for it is not being awkward.
- Local exhaust ventilation must be thoroughly examined and tested at least once every 14 months, or at the shorter interval in Schedule 4 for the processes listed there. That record is kept at least five years.
- Exposure monitoring records are kept at least five years, or at least 40 years where representative of the personal exposures of identifiable employees.
- Health records under health surveillance are kept at least 40 years from the last entry.
Common questions
Does COSHH apply if I have fewer than five employees?
Yes. The regulations apply to every employer. What the five-employee threshold in regulation 6(4) changes is only the duty to record the significant findings in writing. A smaller employer must still assess the risk and prevent or adequately control exposure, and will usually be asked for a written assessment.
Is a safety data sheet the same as a COSHH assessment?
No, and treating one as the other is a common failure. A safety data sheet is the supplier's information about the substance in general. A COSHH assessment is your judgement about the risk arising from how you use it: quantity, process, ventilation, duration and the people exposed.
Does COSHH cover asbestos, lead and construction dust?
Dust yes, asbestos and lead no. Regulation 5 disapplies COSHH where the Control of Asbestos Regulations 2012 or the Control of Lead at Work Regulations 2002 apply, because each has its own regime. Construction dusts such as respirable crystalline silica and wood dust sit within COSHH.
How long do COSHH records have to be kept?
It depends on the record. Local exhaust ventilation examination and test records are kept at least five years. Exposure monitoring records are kept at least five years, or at least 40 years where they represent the personal exposures of identifiable employees. Health surveillance records are kept at least 40 years.
Related
Back to the Procurement & compliance glossary · All glossary terms
Need this checked against a real specification?
Definitions only get you so far. Send us the actual requirement - a PPE schedule, a fixings list, a PQQ question or a marking you cannot make sense of - and the TES team will come back with what matches it. Trade pricing is on the B2B portal.