Class A fires involve which of the following?

Class A fires involve which of the following?

• A. Flammable liquids
• B. Electrical equipment
• C. Ordinary combustibles
• D. Combustible metals

Answer: (C)

Fires involving ordinary combustibles are Class A. These fuels include solid materials like wood, paper, cloth, and many common household items. The key feature is that they burn and typically leave ash, and the way to suppress them effectively is to remove heat. Water-based extinguishing methods are especially good here because water absorbs a lot of heat; as it heats and turns to steam, it cools the fuel and slows or stops the combustion process. In contrast, other fire classes address different fuels: flammable liquids form Class B fires, electrical equipment fires are Class C, and combustible metals fall under Class D. Using water on those can be unsafe or ineffective—for example, water can spread flammable liquids, conduct electricity, or react with certain metals.

Fires involving ordinary combustibles are Class A. These fuels include solid materials like wood, paper, cloth, and many common household items. The key feature is that they burn and typically leave ash, and the way to suppress them effectively is to remove heat. Water-based extinguishing methods are especially good here because water absorbs a lot of heat; as it heats and turns to steam, it cools the fuel and slows or stops the combustion process.

In contrast, other fire classes address different fuels: flammable liquids form Class B fires, electrical equipment fires are Class C, and combustible metals fall under Class D. Using water on those can be unsafe or ineffective—for example, water can spread flammable liquids, conduct electricity, or react with certain metals.