Basic Firefighter Written Practice Exam

Which class of fires involve combustible metals and alloys?

1. Class A

2. Class B

3. Class C

4. Class D

The correct answer is: Class D

Class D fires specifically involve combustible metals and alloys, such as magnesium, aluminum, titanium, and sodium. These types of fires are unique because the metals can react with water and can burn at extremely high temperatures, making them particularly challenging to extinguish. Extinguishing Class D fires requires specialized extinguishing agents or methods, as water or common extinguishing agents may exacerbate the fire. For instance, using water on a magnesium fire can cause violent reactions and flare-ups. Understanding the classification of fires is crucial for firefighters in order to select the appropriate firefighting techniques and agents. This knowledge helps ensure not only the effectiveness of the response but also the safety of personnel and the public.