Understanding Fire Codes When Designing a Fire Suppression System

Class A fire is ordinary combustibles - wood, paper, cardboard, cellulose plant material. Class B fire is flammable liquids, hydrocarbon based - gasoline, kerosene, diesel fuel, tires, plastics. Class C fire is energized electrical fire. Unfortunately, nothing puts out a class C fire, until the power providing the energy is killed. Then, you typically have a class A or class B fire left behind, so a class C fire is a bit of an anomaly. Class D fire is flammable metals - magnesium, lithium (like the batteries in electric vehicles), potassium, flammable salts, etc. Finally, Class K fire is kitchen grease - plant and animal fats, etc.