√  Wet Chemical Extinguisher – Use for Class K Fires

Developed specifically for cooking fires involving oil or fat, the wet chemical extinguisher is one of the newest options on the market. The active ingredient is potassium acetate, and when activated, it sprays a fine mist that cools the flames and prevents splashing, then creates a foam layer that smothers the fat. You’re less likely to see these around unless you happen to work in a commercial kitchen that uses a hot oil immersion fryer (think French Fries) and commercial stove tops, all of which is covered by a listed or approved exhaust hood.

√  Carbon Dioxide Extinguisher – Use for: Class B, C, D, K Fires

It’s not effective on Class A fires, but a carbon dioxide extinguisher works by decreasing the concentration of oxygen in the immediate vicinity of the flame and by absorbing heat energy from the flame. Keep in mind that it must be used at a close range of 3-8 feet.

√  Clean Agent Extinguisher – Use for Class A, B & C Fires

Clean agent extinguishers contain one of several clean agent chemicals, which were developed to replace ozone-depleting halons previously used in portable extinguishers. Clean agents exit the extinguisher as a liquid and vaporize enroute to the base of the fire, which is why they are referred to as “streaming agents”. Clean agents extinguish the fire primarily by chemical reaction with the fire chemistry. Clean agent extinguishers are available for Class A, B and C fires. They are ideal for use in data centers with sensitive electronics because they leave to residue behind that could be harmful to the electronic equipment.

√  Water Mist Extinguisher- Use for Class A and C Fires

An alternative to clean agent extinguishers where contamination is a concern, water mist extinguishers remove the heat element of the fire tetrahedron, and also cool the burning fuel. They can be safe for Class C, but are intended primarily for Class A fires.

√  Foam Extinguisher – Use for Class A and B Fires

Foam extinguishers are best for Class B spill fires, because the foam agent blankets the surface and prevents the flammable liquid vapors from contacting oxygen in the air. The foam extinguishing agent is water-based so the extinguishers are also appropriate for Class A fires, but unsafe for use on Class C fires.

√  Dry Powder Extinguisher – Use for Class D Fires

The method is similar to that of the dry chemical extinguisher in that it coats the fuel with a thin layer of dry chemical powder to create a barrier, but it’s only effective on fires that involve combustible metals.