Types of Fire Extinguishers
To understand the types of fire extinguishers, you need to first understand the common types of fires. Household fires fall under three classifications, depending on the type of fuel burning: A, B, and C.
- Class A: Solid combustibles that are not metals, like wood, paper, cloth, plastics, rubber.
- Class B: Flammable liquids like gasoline, oil, grease, and paints.
- Class C: Electrical equipment, like appliances and outlets.
Household extinguishers fight specific types of fires. It’s important to know the type of fire that has started before you use a fire extinguisher on it; different extinguishers use different chemical fueling agents to fight fires and are effective only on specific types of fuel. If you use the wrong type of extinguisher, you can actually make a fire worse.
- Air-Pressurized Water Extinguishers (APW):
APW extinguishers use pressurized water to fight Class A fires only. These extinguishers are generally about 2 feet tall and 25 pounds when full and will have a pressure gauge. Do not use water on Class B or C fires, as they may cause the fire to spread or increase the possibility of electrical shock.
Foam extinguishers are effective against Class A and B fires. They are not recommended for Class C, but are safer than APW extinguishers if accidentally used on a live electrical device. These foam fire extinguishers are generally marked with a blue band and can vary widely in size.
- Carbon Dioxide Extinguishers (CO2):
Carbon Dioxide extinguishers use non-flammable CO2 gas to fight Class B and C fires. They are not generally effective against Class A fires. These extinguishers do not a have a pressure gauge and can range from 5 to 100 pounds.
- Dry Chemical Extinguishers (DC):
Dry Chemical extinguishers may be labeled ABC or BC to indicate which types of fires they can be used on. They are generally filled with monoammonium phosphate and are pressurized using nitrogen. They range from 5 to 20 pounds and have a pressure gauge.
Most residential fire extinguishers use dry chemicals and are classified ABC to effectively combat all three common household fire types. Rechargeable extinguishers are heavier, but they are sturdier and can be refilled and reused. Disposable extinguishers with plastic valves are lighter and cheaper than rechargeable extinguishers, but they have a shorter shelf life and can be used only once. Cover all your bases and get an ABC fire extinguisher so you’ll be prepared for anything.