Reactive metals such as sodium and lithium belong to which fire class?

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

Answer: (D)

Fires are categorized by the type of fuel involved. Reactive metals like sodium and lithium burn as metal fires, which behave very differently from ordinary combustibles or liquids. That’s why they’re placed in the metal-fire class, Class D. Water and standard extinguishing media are inappropriate here because these metals react vigorously with water, producing hydrogen gas and a lot of heat, which can cause an explosion or spread the fire. The safer, effective approach is to use a dry powder extinguishing agent designed for metal fires (or cover the burning metal with sand or a compatible metal-fire suppressant) to isolate it from air and cool it without provoking a violent reaction.