When discussing Fire we can refer to the Fire Tetrahedron because there are four elements that must be present for a fire to exist. There must be oxygen to sustain combustion, heat to raise the material to its ignition temperature, fuel to support the combustion and a chemical reaction between the other three elements.
Not all fires are the same. Different fuels create different fires and require different types of fire extinguishing agents.
Class A fires are fires in ordinary combustibles such as wood, paper, cloth, trash, and plastics.
Class B fires are fires in flammable liquids such as gasoline, petroleum oil and paint. Class B fires also include flammable gases such as propane and butane. Class B fires do not include fires involving cooking oils and grease.
Class C fires are fires involving energized electrical equipment such as motors, transformers, and appliances. Remove the power and the Class C fire becomes one of the other classes of fire.
Class D fires are fires in combustible metals such as potassium, sodium, aluminum, and magnesium.
Class K fires are fires in cooking oils and greases such as animal’s fats and vegetable fats.
Some types of fire extinguishing agents can be used on more than one class of fire. Others have warnings where it would be dangerous for the operator to use a fire extinguishing agent. Remove any one of the four elements to extinguish the fire.
Thanks for stopping in - the types of Fire Extinguishers and some basic rules for firefighting will be in the next post.