What are the "ABC's" of fires? And why is that label on my extinguisher?
Fires are classified as A, B & C class fires. There is even a 'D' but it's not relevant of residential or most commercial venues.
Let's start with the basics: A fire requires three elements: something that will burn, enough heat to make it burn and oxygen. Remove any one of those three and the fire will go out.
Class A : Anything that leaves an ash. This includes ordinary combustibles such as wood, cloth or paper.
Class B : Flammable liquids - gasoline, oil or oil-based paint.
Class C : Electrical fires - wiring, appliances, fuse boxes, circuit breakers and machinery.
Class D : Combustible metals - magnesium or sodium.
Look on any extinguisher and you will see icons that show you where the extinguisher can be used. A red slash through any icon indicates that they extinguisher is not to be used on that type of fire.