Question

Which of the following types of fire extinguishers should not be used to extinguish an electrical fire?

• A. Carbon dioxide
• B. Mechanical foam
• C. Dry chemical powder
• D. ABC dry powder

Hint:

For electrical fires, use non-conductive fire extinguishers like carbon dioxide or dry powder. Avoid using foam-based extinguishers.

Answer 1

The Correct Option is B

To determine which type of fire extinguisher should not be used on an electrical fire, we will review the function and suitability of each type of extinguisher listed in the options.

1. Carbon dioxide (CO₂): CO₂ extinguishers are suitable for electrical fires. They work by displacing oxygen and reducing the oxygen levels around the fire, thus extinguishing it. Furthermore, CO₂ is non-conductive, making it safe for use on electrical fires.
2. Mechanical foam: Foam extinguishers are not suitable for electrical fires. They contain water, which conducts electricity, leading to the risk of electric shock. Therefore, they should not be used in situations involving live electrical equipment.
3. Dry chemical powder: These extinguishers are effective on electrical fires. They work by interrupting the chemical reaction of the fire triangle, and like CO₂ extinguishers, they are non-conductive and safe for use on electrical equipment.
4. ABC dry powder: This is a type of dry chemical powder extinguisher that is also suitable for electrical fires. Like the other powders, it is non-conductive and effective in dealing with fires involving electrical equipment.

Based on the analysis above, the type of fire extinguisher that should not be used on an electrical fire is the Mechanical foam extinguisher.