The labels on fire extinguishers distinguish the types of fires they can be used upon and indicate the amount of extinguishing agent contained. Fires are given different categories because some extinguishing agents will only extinguish certain types of fire. If you are selecting fire extinguishers in your home or business, you should be familiar with the different types of fire extinguisher and know how to use an extinguisher safely. Learn how to operate extinguishers before a fire occurs, so you can deal with the situation safely.
2-A Fire Extinguishers
The number code on extinguishers represents how much water the extinguishing agent is equivalent to. Each number unit of this code represents 1.25 gallons of water; therefore a code of 2 on an extinguisher represents extinguishing agent equivalent to 2.5 gallons of water. The alphabetic code on extinguishers indicates the category of fire they can be used upon. Category A fires are combustible materials fires.
Category A Fires
Category A, or combustible materials, fires consist of fires involving paper, wood, fabrics, rubber or certain types of plastics. These fires have low combustion temperatures, so they burn easily and quickly. A category A fire extinguisher is generally silver in color and holds water under extreme pressure.
Risks of Category A Fire Extinguishers
Water-based fire extinguishers are useful for combustible materials fires, however, they should never be used on electrical fires or hot-oil fires, such as in a deep fat fryer. It is extremely dangerous to use water on electrical fires, as you run the risk of electrical shock. Using water extinguishing agents on deep fat fryers will make the fire spread quicker, due to the extremely high temperatures of burning oil.
Fire Extinguisher Categories
Fire extinguishers labeled B are suitable for flammable liquids fires, such as burning oils, paints or gasoline. B type extinguishers contain carbon dioxide. Category C fire extinguishers contain dry chemical powders and should be used on electrical fires, such as those started by faulty appliances or wiring. Multipurpose extinguishers are labeled A, B and C and can be used on any fire; they contain dry chemicals. Category K extinguishers contain wet or dry chemicals and are specifically for use on hot, burning oil fires in the kitchen.