Which fire extinguisher for which fire?
You don't fight a chip-pan fire the way you fight a burning bin. The right extinguisher depends on what's actually burning — the fire's class. Here's the class-by-class guide.
Fires are grouped by what's burning — their class (BS EN 2). The right extinguisher matches the class; the wrong one can make things violently worse. Here's the class-by-class rundown.
Class A — wood, paper, textiles
The everyday fire. Use water, foam, or water mist — they cool the fuel below its ignition point.
Class B — flammable liquids (petrol, oil, solvents)
Use foam (blankets the surface), CO2, or dry powder. Never water — it spreads burning liquid.
Class C — flammable gases
The first action is to isolate the gas supply if it's safe to do so. Dry powder is the extinguisher for gas fires — but a burning gas leak is usually a job for the fire service, not a first-aid extinguisher.
Class D — metals
Burning metals (magnesium, swarf) need a specialist powder made for the metal — ordinary ABC powder won't do. Rare outside industry.
Electrical fires — not a class
There's no "Class E." An extinguisher safe near live electrics carries a spark symbol: use CO2 (no residue, kind to equipment) or dry powder. Never water or foam. Cut the power first if you can — then it becomes whatever class the burning material is.
Class F — cooking oils & fats
The chip-pan and deep-fat-fryer fire. Only wet chemical is designed for it — it reacts with the oil to form a sealing, cooling layer. Never throw water on burning oil, and never move a burning pan.
Paper/wood → water or foam. Petrol/oil-based liquid → foam, CO2 or powder. Live electrics → CO2 or powder. Cooking oil → wet chemical. Gas or metal → isolate/specialist, and think fire service.
Before you pick anything up
Only tackle a small fire, with your back to a clear exit, once the alarm's raised and people are leaving. If it's bigger than a bin, or you're unsure — get out, stay out, call 999. Not sure which colour is which? See the fire extinguisher colour chart and our colours & types guide.
Practise matching them
The Extinguisher Match drill throws real fires at you and asks for the right unit — against the clock, the way it happens for real.
Play Hazard Hunt →This guide is for learning and applies to England & Wales. Always work from the current standards and your own fire risk assessment; Scotland and Northern Ireland have equivalent regimes.