Work out fire extinguisher sizing instantly with clear inputs, formula shown and shareable results.
The usual rule provides one 13A rated unit per 200 square metres of light or ordinary hazard floor space, doubled for high hazard, with a minimum of two per floor and no more than 30 metres travel distance. The travel distance limit often drives the count more than the area rule, because a long thin floor plan needs extra units to keep everyone within 30 metres.
Units per floor
per floor = maximum of the minimum and ceiling(floor area / coverage per unit)
General guidance only. Fire extinguisher provision must follow your local fire safety regulations and a competent risk assessment.
per floor = maximum of the minimum and ceiling(floor area / coverage per unit). The usual rule provides one 13A rated unit per 200 square metres of light or ordinary hazard floor space, doubled for high hazard, with a minimum of two per floor and no more than 30 metres travel distance.
The travel distance limit often drives the count more than the area rule, because a long thin floor plan needs extra units to keep everyone within 30 metres.
Enter floor area to protect, hazard level, number of floors. The defaults shown are a realistic worked example — swap in your own figures to get a result you can use.