Firefighter Practice Exam

Which fire extinguisher should be used for fires in live electrical equipment?

1. Water

2. Carbon Dioxide

3. Dry Chemical

4. Foam

The correct answer is: Dry Chemical

Using a dry chemical fire extinguisher for fires involving live electrical equipment is appropriate because these extinguishers can safely suppress flames without conducting electricity. Dry chemical extinguishers typically use agents like monoammonium phosphate or sodium bicarbonate, which are non-conductive and effective in disrupting the combustion process of various types of fires, including those involving electrical sources. When dealing with live electrical equipment, safety is paramount, and non-conductive agents are crucial to prevent the risk of electric shock. Other extinguisher types, such as water or foam, can create a hazardous situation due to their conductivity, potentially worsening the fire or causing injury to the firefighter or bystanders. Carbon dioxide extinguishers could also be utilized in these scenarios because they do not conduct electricity; however, dry chemical extinguishers are often the first choice due to their versatility and effectiveness against a broader range of fire types, including A, B, and C class fires.