Fire extinguishers are categorized based on the type of fuel they are designed to put out. Using the wrong type on a fire can be dangerous.

Types of Fire Extinguishers

1. Water Fire Extinguishers (Class A)

These are the most common type for fires involving organic solid materials.

• Best for: Paper, wood, straw, textiles, and coal.

• How it works: It cools the fire by soaking the materials and absorbing the heat.

• Note: Never use on electrical fires or burning fat/oil.

2. Foam Fire Extinguishers (Class A & B)

Foam extinguishers are highly versatile and more effective than water for certain risks.

• Best for: Organic solids (Class A) and flammable liquids like petrol, diesel, or paint (Class B).

• How it works: It creates a cooling blanket over the fuel, sealing the surface and preventing flammable vapors from reaching the air.

• Note: Not recommended for kitchen fires involving deep fat fryers.

3. Dry Powder Fire Extinguishers (Class A, B, C & Electrical)

Often called “ABC” extinguishers, these are multi-purpose and very common in industrial settings.

• Best for: Organic solids, flammable liquids, and flammable gases (Class C) like methane or butane. They are also safe for electrical fires.

• How it works: The powder acts as a thermal blast that smothers the fire and stops the chemical reaction.

• Note: The powder can impair vision and cause respiratory issues in enclosed spaces.

4. Carbon Dioxide (CO2) Fire Extinguishers (Class B & Electrical)

CO2 extinguishers are the standard for offices and server rooms because they leave no residue.

• Best for: Flammable liquids and electrical hazards (computers, panels, generators).

• How it works: It suffocates the fire by displacing the oxygen the fire needs to burn. It also provides a cooling effect.

• Note: CO2 can cause frostbite if the horn is held during discharge, and it is not effective for Class A fires.

5. Wet Chemical Fire Extinguishers (Class A & F)

Specifically designed for kitchen environments with high-temperature oils.

• Best for: Cooking oils and fats (Class F) and organic solids.

• How it works: It creates a soapy layer over the burning oil (saponification), which cools the oil and prevents re-ignition.

• Note: This is the only type safe for large-scale deep fat fryer fires.

6. Clean Agent (Halotron) Fire Extinguishers (B, C & Electrical)

These are eco-friendly alternatives to older chemical agents, used for high-value equipment.

• Best for: Sensitive electronics, data centers, and aircraft.

• How it works: It uses a non-conductive volatile liquid or gas that leaves no residue and does not cause thermal shock to electronics.