Which class of fire involves ordinary, solid, combustible materials such as wood, cloth, and paper?

Which class of fire involves ordinary, solid, combustible materials such as wood, cloth, and paper?

• A. Class A Fires
• B. Class B Fires
• C. Class C Fires
• D. Class D Fires

Answer: (A)

Fires that involve ordinary solid combustibles such as wood, cloth, and paper burn with the fuel itself becoming ash. This category is designated for those materials because they require cooling to remove heat, typically with water, to reach below the ignition temperature and suppress the flame. Water is especially effective here because it absorbs a lot of heat as it boils away. This is different from other fire types: flammable liquids involve vapors and are treated as a different class with extinguishing methods suited to liquids; electrical fires involve energized equipment and require nonconductive agents and de-energizing the circuit; and certain reactive metals require special extinguishing agents. Understanding these distinctions helps responders choose the right approach and extinguishing agent for the fire at hand.

Fires that involve ordinary solid combustibles such as wood, cloth, and paper burn with the fuel itself becoming ash. This category is designated for those materials because they require cooling to remove heat, typically with water, to reach below the ignition temperature and suppress the flame. Water is especially effective here because it absorbs a lot of heat as it boils away.

This is different from other fire types: flammable liquids involve vapors and are treated as a different class with extinguishing methods suited to liquids; electrical fires involve energized equipment and require nonconductive agents and de-energizing the circuit; and certain reactive metals require special extinguishing agents. Understanding these distinctions helps responders choose the right approach and extinguishing agent for the fire at hand.