Which fire class involves burning metals such as magnesium or aluminum, for which Halon cannot be used?

Which fire class involves burning metals such as magnesium or aluminum, for which Halon cannot be used?

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

Answer: (D)

Metals that burn, like magnesium or aluminum, fall into Class D fires. These fires are extremely hot and can react violently with common extinguishing agents such as water or some Halon formulations. Halon extinguishers disrupt chemical reactions but don’t reliably stop the oxidation process happening in metal fires, and they aren’t designed to insulate the metal from oxygen. Instead, a dry powder designed for metals blankets the burning material, helps absorb heat, and isolates it from air, forming a crust that slows or stops the reaction. That specialized dry powder approach is why metal fires are handled as Class D.

Metals that burn, like magnesium or aluminum, fall into Class D fires. These fires are extremely hot and can react violently with common extinguishing agents such as water or some Halon formulations. Halon extinguishers disrupt chemical reactions but don’t reliably stop the oxidation process happening in metal fires, and they aren’t designed to insulate the metal from oxygen. Instead, a dry powder designed for metals blankets the burning material, helps absorb heat, and isolates it from air, forming a crust that slows or stops the reaction. That specialized dry powder approach is why metal fires are handled as Class D.