A Class K extinguisher is designed for fires involving which type of material?

A Class K extinguisher is designed for fires involving which type of material?

• A. Class A materials
• B. Cooking oils and fats
• C. Electrical equipment
• D. Metals

Answer: (B)

Fires involving cooking oils and fats are the type a Class K extinguisher is designed to handle. The special wet chemical agent (potassium acetate) reacts with fats to saponify them, turning the oil into a soapy, non-flammable layer that cools the oil, smothers the fire, and helps prevent reignition. This targeted action makes Class K ideal for high-temperature, greasy fires found in commercial kitchens, such as those with deep-fat fryers. It’s different from fires caused by ordinary combustibles like wood or paper, which need extinguishers suited for those materials, and from electrical fires, which require suppression methods that avoid electrical conductance. Metal fires also require a different approach with agents designed for reactive metals.

Fires involving cooking oils and fats are the type a Class K extinguisher is designed to handle. The special wet chemical agent (potassium acetate) reacts with fats to saponify them, turning the oil into a soapy, non-flammable layer that cools the oil, smothers the fire, and helps prevent reignition. This targeted action makes Class K ideal for high-temperature, greasy fires found in commercial kitchens, such as those with deep-fat fryers.

It’s different from fires caused by ordinary combustibles like wood or paper, which need extinguishers suited for those materials, and from electrical fires, which require suppression methods that avoid electrical conductance. Metal fires also require a different approach with agents designed for reactive metals.