Which type of fire extinguisher should be used on combustible metals?

The correct choice for extinguishing fires involving combustible metals is the Class D fire extinguisher. These extinguishers are specifically designed for materials such as magnesium, titanium, potassium, and sodium, which are known to ignite and burn at very high temperatures and react dangerously with water.

Class D fire extinguishers typically contain dry powder agents that smother the fire and prevent oxygen from reaching the burning metal. This is critical because using other types of extinguishers, such as those for organic materials, flammable liquids, or electrical equipment, would not be effective and could even exacerbate the situation. For instance, using water from a Class A extinguisher could cause a violent reaction with burning metals.

Thus, understanding the specific applications of each class of fire extinguisher is essential for effective fire management and safety. The Class D extinguisher is the appropriate choice to handle the unique challenges posed by combustible metals.