Mobile Fire here to help you go over the different classes of fire.
Class “A” fires can involve any material that has a burning ember or leaves an ash such as wood, paper, cloth, rubber, many plastics, etc.
Class “B” fires involve flammable liquids and gases such as motor oil, paint thinner, dry cleaning agents, gasoline, propane, natural gas, etc. Flammable liquids do not ignite in the liquid state but rather it is the vapors being generated by these liquids that ignite.
Class “C” fires involve live electrical equipment and require the use of an extinguishing agent and/or extinguisher that will not conduct electricity.
Class “D” fires involve exotic metals such as sodium, magnesium, and titanium. These fires require specials agents and special application techniques different from agents and techniques used on Class “A”, “B”, or “C” fires. Some agents like water will actually react to burning metals and increase the intensity of the fire in a violent manner.
Class “K” fires involve combustible cooking media such as vegetable or animal oils and fats. These fires require wet chemical extinguishers that have superior cooling capabilities to lower the temperature of the cooking medium below its auto ignition point.