Classes of Fires & Fire Extinguisher Types

4/27/2022 (Permalink)

Classes of Fires

Class A: Solid ordinary combustibles like paper, wood, cloth, and plastics.

Class B: Flammable liquids like alcohol, ether, gasoline, and grease. These are extinguished by smothering, which is cutting off the oxygen supply from a fire.

Class C: Electrical Equipment, home appliances, and wiring. This requires a nonconductive extinguishing agent that prevents injury from electrical shock. DO NOT USE WATER.

Class D: Certain flammable metallic substances like sodium and potassium.

Fire Extinguishers

Fire extinguishers are classified by type A, ABC, BC, or K. It is important to use the correct type on the specific fire to avoid injury. Using the wrong type could cause electrical shock, explosion, and spread of the fire. Portable fire extinguishers are good for putting out small fires but are not useful on large spreading fires.

Types of Extinguishers

Type A: Pressurized water and can be used on Class A fire ONLY. Can cause spread or electrical sock if used on the wrong class.

Type ABC: Dry chemicals that can be used on all classes of fires.

Type BC: Carbon Dioxide that can be used on electrical and chemical fires.

Type K: Used in kitchens on grease fires.

For more information, visit Classes of Fires & Fire Extinguishers - Environmental Health & Safety - Los Angeles, CA (uclahealth.org).