Write a COSHH assessment

Assess the task, not just the substance — exposure, controls and limits, published as a signed version.

6 min read · Last reviewed 18 August 2026

Assess the task

1
From the substance, create the assessment for the task that uses it — “degreasing parts”, not “acetone in general”.
2
Work through exposure routes, who is exposed, and the controls: ventilation, PPE, storage, hygiene, emergency measures.

Tip: One substance, several tasks, several assessments is normal. Spraying and wiping are different exposures wearing the same label.

1
Enter the workplace exposure limits that apply, from the SDS and EH40.
2
Record monitoring results against them as you get them — a result over the limit is flagged rather than filed.

1
Publish when the assessment is ready. Publishing freezes a signed, immutable copy — the version that was attested.
2
Edit the live assessment whenever reality changes; publishing again writes the next version, and the old ones stay readable.

Note: The signed copy is what protects the assessor: an assessment edited after the event with no version history protects nobody.