Class K fires involve:

• A. Oils and greases.
• B. Flammable liquids.
• C. Energized electrical equipment.
• D. Noncombustible materials.

Answer: (A)

Fires are categorized by the fuel involved and the extinguishing method best suited to that fuel. Class K is reserved for cooking media—specifically oils and greases used in commercial kitchens. These fats ignite and burn at high temperatures and require a specialized agent: wet chemical extinguishers that saponify the fat (turn it into a soapy layer) and then cool and smother the flame. That’s why oils and greases are the correct focus here. Fires involving energized electrical equipment belong to a different class and are treated with nonconductive extinguishing methods, while noncombustible materials don’t constitute a fire that Class K covers. Flammable liquids cover many fuels, but in a kitchen context cooking oils are designated Class K because of the unique suppression approach they demand.