How many fire extinguishers do I need? AS 2444 calculator

Use this free calculator for a quick estimate of the portable fire extinguishers your premises may need, based on the principles of AS 2444 — Portable fire extinguishers and fire blankets (Selection and location). It’s a guide only — a starting point, not an exact or final count. The right number and type for your site depends on your building class, age, the hazards present and your layout, and should be confirmed on site by a licensed fire safety technician. Choose your premises type, floor area and any special risks, and we’ll suggest suitable extinguishers from our range.

What’s my hazard level? (AS 2444)
Light — offices, homes, schools, churches, assembly halls.
Ordinary — shops, showrooms, storage & display areas, workshops.
High — woodworking, high-piled storage (over 4.5 m), foam plastics, flammable-liquid handling.
Per floor — repeat for each storey. No point should be more than 15 m (10 m for a 2.5kg) from an extinguisher; mount the handle no higher than 1200 mm above the floor.
Shop fire extinguishers →
Rough estimate only (per floor). Your actual requirement depends on your building class, year built, the specific hazards present and your floor layout — all of which must be reviewed on site. Use this as a starting point, then have a licensed fire safety technician confirm your requirements under AS 2444.

How the calculator works

AS 2444 selects and locates extinguishers by the hazard present and the maximum travel distance to the nearest unit — not simply by floor area. Our calculator applies practical, conservative coverage based on those principles:

  • Light & ordinary hazard: up to 150 m² → one 2.5kg ABE; 150–225 m² → one 4.5kg ABE; over 225 m² → one 4.5kg ABE per 225 m².
  • High hazard: one 4.5kg ABE (high performance) or 9kg ABE per 200 m².
  • Commercial kitchens: add a 1.2 m × 1.8 m fire blanket; if there’s a deep fryer, add a wet chemical extinguisher (2 L for oil under 20 L, 7 L for 20 L and over).
  • Electrical risk: add a CO² extinguisher near switchboards — 3.5kg for a server room or regular switchboard, 5kg for a significant switchboard.

Fire hazard classes explained (AS 2444)

Light hazard

Premises where only small fires are expected — offices, homes and residential, schoolrooms, churches and assembly halls.

Ordinary hazard

Moderate fire potential — shops and mercantile storage and display areas, showrooms and workshops.

High hazard

Large fire potential — woodworking, warehouses with high-piled storage over 4.5 m, foam-plastics processing and storage, and flammable-liquid handling. High fuel-load occupancies may warrant a higher classification.

Travel distance and placement

Under AS 2444 the travel distance from any point to the nearest Class A extinguisher should not exceed 15 m (we use 10 m for the smaller 2.5kg unit). Extinguishers should be mounted so the handle is no higher than 1200 mm above the floor, kept clearly visible and accessible, and provided on every floor.

Fire extinguishers for vehicles

AS 2444 also covers vehicles, caravans, trucks and boats (Section 5). As a guide, a car or utility needs at least one 1A:5B extinguisher, multi-compartment caravans need two, and commercial or cargo vehicles need a hose-fitted unit in the cabin. See our vehicle fire extinguisher range for compliant options.

Frequently asked questions

How many fire extinguishers does my business need?

It depends on your hazard level, floor area and the specific risks present. As a rough guide under AS 2444, a light or ordinary-hazard workplace needs about one 4.5kg ABE extinguisher per 225 m² per floor, with smaller premises (under 150 m²) covered by a single 2.5kg ABE. Use the calculator above for an estimate, then confirm with a licensed technician.

What size fire extinguisher do I need for an office?

Most offices are a light hazard. A single 2.5kg ABE covers up to 150 m²; larger offices step up to 4.5kg ABE units, plus a CO² extinguisher where there are significant switchboards or server equipment.

Do I need a fire extinguisher on every floor?

Yes. Travel-distance requirements apply per floor, so each storey needs its own extinguishers — this calculator estimates one floor at a time.

What extinguisher do I need for a commercial kitchen?

A wet chemical extinguisher for cooking-oil (Class F) fires — 2 L for fryers under 20 L of oil, 7 L for 20 L and over — plus a 1.2 m × 1.8 m fire blanket at the cooktop, and a general ABE extinguisher for the rest of the space.

Is this calculator a substitute for a fire safety assessment?

No. It provides a rough estimate only. Your actual requirements depend on building class, age, hazards and layout, which must be reviewed on site by a licensed fire safety technician.

Also need a vehicle extinguisher? Use our Vehicle Fire Extinguisher Selector — matched to AS 2444 for cars, caravans, boats and commercial vehicles.