COSHH
Also known as: Control of Substances Hazardous to Health
COSHH is the UK law requiring employers to assess and control exposure to hazardous substances such as dust, fumes and chemicals.
- The regulations covering substances that can harm health, from silica dust to solvents.
- You must assess the risk, control exposure, and keep a record of both.
- It applies to any size of business. There is no lower threshold.
COSHH stands for the Control of Substances Hazardous to Health Regulations 2002. They require employers to assess the risk from hazardous substances, prevent or adequately control exposure, and keep the records that show they have done so.
The word “substances” is broader than most people assume. It covers what you buy in, such as solvents, adhesives, resins and cleaning products. It also covers what the work creates: silica dust from cutting and grinding, wood dust, welding fume, exhaust from plant running in an enclosed space. Nobody supplies those, so nobody hands you a safety data sheet for them, and they are routinely the ones that get missed.
What an assessment has to do
A COSHH assessment is not a form-filling exercise, though it usually ends up as a form. It has to work through what the substance is, who is exposed to it, how much and for how long, and what will bring that exposure down.
Controls follow the hierarchy of control, and the order matters. Can the substance be designed out, or bought in a form that does not create dust? Can a less harmful product do the job? Can extraction, water suppression or enclosure stop the exposure at source? Only when those have been worked through does PPE come into it, and respiratory protection in particular needs face-fit testing and maintenance to do anything at all.
Where a control depends on equipment, that equipment has to keep working. Local exhaust ventilation needs thorough examination and testing at least every 14 months, and the record of that test is part of your COSHH evidence.
Where it goes wrong on site
The common failure is not a missing assessment. It is an assessment that describes a method nobody uses. A generic assessment downloaded for a product, filed, and never revisited when the sequence changed or a different product arrived on site tells an inspector that the duty was treated as paperwork.
The second failure is health surveillance. Where exposure to certain substances continues despite controls, you may need to monitor the people exposed. That obligation sits alongside the assessment rather than being replaced by it.
Keeping each assessment against the job it belongs to, with the review date visible and the method statement it supports beside it, is what turns the file into something usable. That is the part Sync’s risk management is built for.
Serious ill health caused by a substance is reportable under RIDDOR, and occupational disease claims can surface years after the work finished, which is why the record matters long after the site closes.
Common questions
Does COSHH apply to a two-person crew?
Yes. There is no lower size threshold. A sole trader with employees, or a two-person team cutting block indoors, has the same duty to assess and control as a national contractor. What changes is the scale of the paperwork, not whether the duty exists.
Is a COSHH assessment the same as RAMS?
No. RAMS covers a task; a COSHH assessment covers a specific substance. In practice the COSHH assessment is referenced by, and issued with, the RAMS for the work.
Does a safety data sheet count as a COSHH assessment?
No, though it is where you start. The supplier's safety data sheet tells you what is in the product and what it can do. The COSHH assessment is your own judgement about what happens when your people use it, in your quantities, in your working conditions.
What about dust created by the work itself?
It counts. Silica dust from cutting, grinding or chasing is one of the most serious COSHH risks in construction and it has no safety data sheet, because nobody supplied it. The duty to assess and control it is the same.
More Health & Safety terms
All 14 in this categoryKeep the paperwork where the work is
Sync keeps your health and safety records against the projects they belong to, with review dates tracked, so the current version is there when someone asks for it.