COSHH: chemical storage & mixing Risk Assessment Template

Typical hazards & measures

• Spill containment, bunding and drain protection gaps — Fit bunded trays (≥110% largest container); place spill kits within 10 s; deploy drain covers/socks before wet clean; isolate, absorb, neutralise if required, and bag as hazardous waste; record events and restock kits immediately after use.
• Incompatible chemical mixing — Post a “do-not-mix” chart (e.g., bleach with acids/ammonia/chlorine); colour-code tools for oxidisers vs reducers; keep separate trolleys; never reuse decant cups across families; double-check labels aloud before combining any components.
• Inhalation exposure during mixing (dust/vapour) — Use low-dust powders and gentle decant; mix under local extraction with lids on bowls; cap bottles between passes; offer FFP2/3 on request; wet-wipe benches to avoid re-entrainment; change extraction filters to the posted schedule.
• Power or ventilation loss mid-mix — Stop decanting, close containers, move to bunded trays, increase passive airflow, and record the incident. Restart only after extraction returns and surfaces are wiped; tag any compromised mix for disposal with notes for the shift brief.
• Metal contamination with persulfates — Use plastic or glass bowls and non-metal whisks; inspect clips/tools for exposed metal; keep foils out of mixing vessels; label stations “no metal with bleach”; retire worn utensils that shed plating or filings to prevent catalytic reactions.