Fire Extinguisher Types & Classes of Fire
Which One for Which Fire, and Where (2026)

The classes of fire, and why the letters differ

Fire safety people sort fires by what is burning, because the fuel decides which agent will put it out and which one will make it worse. Wikipedia's fire classification entry notes that classes are often given letters, and that the letters differ between territories that use different standards. The European and Australian schemes and the American one agree on some letters and not on others:

Two practical points follow. First, a letter on its own can mislead: a “Class C” extinguisher in one system is rated for gas fires and in another for electrical fires. Second, the same source explains that an electrical fire, once the power is safely cut, becomes a fire of whatever material is still burning. That is why switching off the supply at the distribution board, where it is safe to do so, is part of fighting an electrical fire.

The main extinguisher types at a glance

The descriptions follow Wikipedia's fire extinguisher entry, which also makes the point that an extinguisher is for a small fire in its first moments, not one that has reached the ceiling or cuts off your way out. When the fire is bigger than that, the extinguisher's job is over and the job is to get everyone out and call Bomba.

Dry powder (ABC): the all-rounder, with a mess

The multipurpose dry powder unit is a common general-purpose choice in shops and offices because one cylinder covers ordinary materials, flammable liquids and gases. Its agent, monoammonium phosphate, melts onto burning solids to smother them. The trade-off is the clean-up: the powder spreads through a room, gets into keyboards and machinery, and the encyclopedia entry notes that it is more corrosive than other dry chemical agents. It is a sensible default by the exit and in stockrooms, and a poor choice right beside a server rack.

Carbon dioxide: switch rooms, counters and server racks

A CO2 extinguisher leaves no residue, which is why it is the usual choice near electrical panels, printers, tills and servers. It works mainly by pushing oxygen away from the fire, so it has two limits. It is weak on deep-seated solid fires such as a smouldering stack of cartons, which can re-ignite once the gas drifts away, and it should not be emptied in a small closed room with people still inside. For a dedicated server or comms room, many owners pair a CO2 unit at the door with a fixed system inside; the fixed fire suppression guide explains the gas systems used in rooms like that.

Water and foam: offices, stockrooms and fabric

Water extinguishers cool burning paper, wood and fabric and are cheap to refill, but they must never be used on live electrics or burning liquids. Foam does the same cooling job and also forms a blanket over a burning liquid, which makes it useful in stores holding paints, solvents or fuel. In an open-plan office full of sockets and cables, most owners find water on its own too limiting and choose powder or CO2 for the general positions.

Wet chemical: the commercial kitchen unit

Cooking oil fires are their own class because the oil is so hot. A jet of water on a burning fryer vaporises instantly and throws burning oil into the air, which is how kitchen fires injure people. Wet chemical extinguishers are made for this: the agent reacts with the hot fat to form a crust that cools it and stops it flaring up again. Commercial kitchens often also have an automatic suppression system built into the exhaust hood over the cooking line; the kitchen exhaust and ducting guide explains how the hood, the ducting and that system fit together.

Reading the label: pictograms, colour bands and service tags

Because letters vary, the pictograms on the label are the reliable guide: small symbols for burning wood, a liquid, a gas cylinder, an electrical plug or a frying pan, with the unsuitable ones crossed out or missing. The same encyclopedia entry explains that European extinguishers have a red body with a coloured panel showing the agent, that Australian units carry a coloured band, and that the United States has no official colour standard, so colour alone is not proof of type.

• Check the agent name and the fire classes or pictograms printed on the body.
• Check the pressure gauge sits in the operating zone where one is fitted.
• Look for the service tag showing the last inspection and who carried it out.
• Look for dents, corrosion, a missing pin or a cracked hose.

Which extinguisher goes where in a shop or office

• Entrance and escape routes: a multipurpose unit where people pass on the way out.
• Tills, printers and the electrical riser: CO2, so a small fire does not ruin the equipment around it.
• Server or comms room: CO2 at the door; ask whether the room also needs a fixed system.
• Commercial kitchen: wet chemical near the cooking line, alongside the hood suppression system.
• Stockroom with cartons, fabric or paper: powder or water-based, depending on what else is stored.
• Workshop with paint or solvent: foam or powder; metals need a special powder.

How many units a premises needs, what size and exactly where they hang is set by the fire safety requirements for that building, so the fire consultant or specialist contractor decides it, not the fit-out drawings alone. The fire safety equipment guide for shops and offices covers who is responsible for which item in a rented unit.

Servicing, refills and records

Most countries require extinguishers to be maintained regularly by a competent person, and the encyclopedia entry records cases of neglected units failing to discharge or even rupturing. In Malaysia, installing and servicing fire equipment is specialist work done by Bomba-registered firms. After any use, even a short burst, the unit must be refilled or replaced, because a partly used cylinder can lose its pressure. Keep the service tags visible and a simple file of service reports; in a building that must hold a Bomba fire certificate, the strata fire safety guide explains why a tenant's neglected equipment can hold up the whole building's renewal.

Extinguishers during a renovation or fit-out

A fit-out is when extinguishers go missing: hidden behind new partitions, boxed into joinery, or taken down and never rehung. Mark every extinguisher position on the layout drawing, keep the brackets clear of cabinets and signage, and keep a unit near any hot work such as welding or torch-on membrane. At handover, walk the unit and check that every position on the drawing has the right type on the wall with a current tag. ClickBina's office renovation and fit-out service plans these positions with the partitions and ceilings, so the fire items are not an afterthought.

How ClickBina can help

ClickBina handles commercial renovation and fit-out works and coordinates the trades. Extinguishers, fire alarms and suppression systems are specialist work, so ClickBina coordinates the licensed specialist and the building management, and makes sure the partitions, ceilings and joinery leave every fire item visible and reachable. WhatsApp us your job details for a quote: the premises type, the floor area, and whether there is a commercial kitchen or a server room. ClickBina is an experienced KL & Selangor contractor; we reply within the hour, the price we agree is a flat price with no hidden charges, and a site visit is RM150, waived if you go ahead.

Sources & methodology

• Wikipedia — Fire classification: the class letters in the European, Australian and American systems; electrical and cooking oil fires.
• Wikipedia — Fire extinguisher: agents, how each works, label colours, maintenance.
• Fire safety equipment guide for shops and offices, and strata fire safety guide (both on this site): who is responsible, specialist servicing, the fire certificate.

Methodology: this guide explains types and uses only. It gives no extinguisher prices or quantities, because those depend on the premises and are set by the fire consultant or specialist contractor.