COSHH on construction sites: assessments, records and common substances
The biggest health harm in construction comes from substances that damage people slowly, and dust is the main one. Here is what COSHH asks of you, and the records that show you did it.
What COSHH requires
COSHH is the Control of Substances Hazardous to Health Regulations 2002. In short, if the work involves a substance that could harm health, the employer must find out what the risk is, stop or control the exposure, and check that the controls work. Substances include chemicals, dusts, fumes, vapours, and also biological agents.
On construction sites that is much more than the cleaning products. The biggest health harm in construction comes from dust and similar exposures that do their damage over years, which is why COSHH matters even when nothing seems to be going wrong.
Common construction substances
- Respirable crystalline silica. From cutting, drilling or grinding concrete, brick, block, stone and mortar.
- Cement and wet concrete. Skin burns and dermatitis.
- Wood dust. From cutting and sanding timber and boards.
- Solvents, paints, adhesives and sealants. Vapours and skin contact.
- Isocyanates. In some spray foams, coatings and sealants.
- Welding and cutting fumes.
- Fuels, oils and exhaust fumes. Particularly diesel engine exhaust in enclosed spaces.
- Mould and biological hazards. In refurbishment and demolition.
Asbestos is covered by its own regulations, the Control of Asbestos Regulations 2012, and has its own rules for surveys, licensing and removal. Do not treat it as an ordinary COSHH item.
How to carry out a COSHH assessment
- Find out what is hazardous. Read the safety data sheet from the supplier and the label. Look at what the task creates too, such as dust from cutting.
- Decide who could be exposed and how. Breathing it in, skin contact, swallowing, eyes. Include other trades and the public.
- Decide what is needed to control the risk. Eliminate or substitute first, then enclose, extract or suppress at source, change the way of working, and finally use PPE and RPE as the last line.
- Put the controls in place and tell people. Give the information, instruction and training, and check people use the controls.
- Check the controls work, and maintain equipment such as extraction and respirators.
- Review. When the work, the substance or the conditions change, and after any incident.
What to record and for how long
- A register of substances on site, with the product, supplier and where it is used.
- The current safety data sheet for each, and a note of the version or date.
- The COSHH assessment, with who is at risk and the controls.
- Training and briefings given, and to whom.
- Maintenance and testing of controls. For example extraction equipment and RPE, including face-fit testing where tight-fitting masks are used.
- Health surveillance, where the assessment says it is needed.
Retention differs by record. Health surveillance records need to be kept for a long time, at least 40 years under COSHH, because ill health can take decades to appear. Check HSE's guidance for the periods that apply to monitoring and other records, and ask your insurer what they expect.
"We have the data sheets in a folder" is not a COSHH assessment. The sheet tells you what the substance can do. The assessment says how it is used on this job and what you are doing to protect people. Inspectors ask for the second.
Common failings
- Dust is not treated as a hazardous substance, so cutting and grinding go ahead dry with no suppression or extraction.
- Generic assessments copied from another job.
- Out-of-date data sheets, or none at all for products brought on by subcontractors.
- RPE that does not fit. A mask that has not been face-fit tested, or worn over a beard, does not protect.
- PPE used as the first control when the dust could have been stopped at source.
- No check that controls work. Extraction with a blocked filter protects nobody.
- Records scattered across vans, offices and email.
The free 3-minute assessment asks about the records you keep for your diary, register and inductions. It is a good first look at where your site paperwork is thin.
Keep your COSHH register in one place
SiteHub keeps a register of the hazardous substances on site, with each substance's COSHH assessment and safety data, its hazards and the control measures in place. It replaces the folder of COSHH sheets.
No card needed. £19 a month for your first site and £15 for each extra site after the trial.
This guide is general information for contractors, not legal advice. COSHH duties depend on your substances and work, so check HSE's guidance (L5) or take advice from an occupational health and safety professional.