Question 213Safety & Environmental - 1st Asst/Chief

The correct answer is D) Class D fires. Dry powder fire extinguishers containing a mixture of graphite and sodium chloride are generally used to fight Class D fires, which involve combustible metals such as magnesium, titanium, and sodium. These types of fires require a specialized extinguishing agent that can smother the fire and prevent reignition, which is what the graphite and sodium chloride mixture in dry powder extinguishers is designed to do. The other answer choices are incorrect because Class A fires involve ordinary combustible materials, Class B fires involve flammable liquids and gases, and Class C fires involve energized electrical equipment, all of which require different types of extinguishing agents.