Associate Safety Professional Practice Exam

What type of extinguishing agent is designated for Class A fires?

1. Chemical agent

2. Water

3. Dry powder

4. Foam

The correct answer is: Water

Class A fires involve materials such as wood, paper, textiles, and some plastics, which are generally combustible and produce ash. The most effective extinguishing agent for Class A fires is water. Water works by cooling the burning material below its ignition temperature and by soaking into the material to extinguish the fire. Water's ability to absorb heat is crucial in controlling and extinguishing Class A fires because it effectively lowers the temperature of the burning materials, thus reducing the chances of re-ignition. Additionally, water can help to prevent the fire from spreading to nearby combustible materials. Other agents, such as foam or dry powder, may be used for specific fire types but are not the most effective for Class A fires. While chemical agents may work on various fires, water remains the standard and most recommended agent due to its availability, effectiveness, and ease of use for extinguishing ordinary combustible fires.