What fire extinguisher to use on a Class D fire?

Classes of fire

Class A – fires involving solid materials such as wood, paper or textiles.

Class B – fires involving flammable liquids such as petrol, diesel or oils.

Class C – fires involving gases.

Class D – fires involving metals.

Class E – fires involving live electrical apparatus. (

Sodium bicarbonate, regular or ordinary used on class B and C fires, was the first of the dry chemical agents developed. In the heat of a fire, it releases a cloud of carbon dioxide that smothers the fire. That is, the gas drives oxygen away from the fire, thus stopping the chemical reaction.

ABC Fire Extinguishers. They use monoammonium phosphate which is a dry chemical that is able to quickly put out the fire. It is a pale yellow powder that is able to put out all three classes of fire; Class A for trash, wood and paper, Class B for liquids and gases, and Class C for energized electrical sources.

Only the class K fire extinguisher is compatible with the wet chemical agents. they are not designed to be used for class K kitchen fires. Class K fires most often occur where cooking media (fats, greases, and oils) are used. These are most often found in commercial cooking operations.

In the UK fires are classed using the European Standard Classification of Fires, which is recognised across the EU.

Class A – Ordinary combustible fires.

Class B – Flammable liquids.

Class C – Flammable gases.

Class D – Metal fires.

Electrical Fires.

Class F – Cooking oil fires.

Fire extinguishers with a Class A rating are effective against fires involving paper, wood, textiles, and plastics. The primary chemical used to fight these fires is monoammonium phosphate, because of its ability to smother fires in these types of materials.

Class B. Class B fires are fires in flammable liquids such as gasoline, petroleum greases, tars, oils, oil-based paints, solvents, alcohols. Class B fires also include flammable gases such as propane and butane. Class B fires do not include fires involving cooking oils and grease.

The triangle illustrates the three elements a fire needs to ignite: heat, fuel, and an oxidizing agent (usually oxygen).

Class A fires consist of ordinary combustibles such as wood, paper, fabric, plastic, and most kinds of trash. These are fires whose fuel is flammable or combustible liquid or gas. The US system designates all such fires “Class B”.

Monoammonium phosphate, ABC Dry Chemical, ABE Powder, tri-class, or multi-purpose dry chemical is a dry chemical extinguishing agent used on class A, class B, and class C fires. It uses a specially fluidized and siliconized monoammonium phosphate powder.

Class D. Class D Fires are combustible metal fires. Magnesium and Titanium are the most common types of metal fires. Once a metal ignites do not use water in an attempt to extinguish it.

There are five main types of fire extinguishers:

Water.

Powder.

Foam.

CO2.

Wet chemical.

In the UK fires are classed using the European Standard Classification of Fires, which is recognised across the EU.

Class A – Ordinary combustible fires.

Class B – Flammable liquids.

Class C – Flammable gases.

Class D – Metal fires.

Electrical Fires.

Class F – Cooking oil fires.

For fire to exist, the following four elements must be present at the same time: Enough oxygen to sustain combustion. Enough heat to raise the material to its ignition temperature. Some sort of fuel or combustible material.

Depending on the agent that fuels the fire, fires are classified into different categories: Class A (regular combustibles), Class B (flammable gasses and liquids), Class C (electrical equipment), Class D (combustible metals), and Class K (cooking fats and oils).

Boats less than 26′ have to have at least one B-1 fire extinguisher on board. Boats 26′-40′ need to have at least two B-1 fire extinguishers on board. If the boat has a USCG approved fire extinguisher system installed for protection of the engine compartment, then the required number may be reduced.

A simple fire extinguisher training technique to use with employees is the PASS method:

PPull the pin on the extinguisher.

AAim the hose nozzle low toward the base of the fire.

SSqueeze the handle to release the extinguishing agent.

SSweep the nozzle from side to side at the base of the flames until extinguished.

Safequip’s range of stored pressure dry chemical powder extinguishers is suitable for class A (combustible materials), class B (flammable or combustible liquids) and/or class C (electrical) fires or a combination of ABC class fires.

Water extinguishers work by removing heat from the fire. Dry chemical extinguishers are tanks of foam or dry powder with compressed nitrogen as the propellant. They work by smothering the fire: when you put a layer of powder or foam on the fire, you cut the fuel off from the oxygen around it, and the fire goes out.

A home single-use fire extinguisher that is capable of fighting A, B or C type fires costs $15-$20. For example, Home Depot sells the Kidde single-use fire extinguisher for $18. Multi-use home and office fire extinguishers typically cost $35-$75. First Alert’s heavy duty rechargeable fire extinguisher costs $60.