Firefighter Practice Exam

In a situation where aluminum chips catch fire, which class of fire extinguisher should be used?

1. Class A

2. Class B

3. Class C

4. Class D

The correct answer is: Class D

The correct answer is Class D, which is specifically designed for extinguishing fires involving combustible metals, such as aluminum. In incidents where fine metal chips ignite, traditional fire extinguishers would not be effective, as they could react adversely with the burning metal. Class D extinguishers use dry powder agents that smother the fire while also preventing oxygen from reaching the burning metal. This is critical because metals like aluminum can burn at very high temperatures and can react violently to water or foam, which are used in Class A, B, or C extinguishers. Understanding the different classes of fire extinguishers is essential in handling fires properly and safely. Each class targets different types of materials, and using the wrong class can either be ineffective or dangerous.