Which fire extinguishing agents are recommended for Class C fires?

Class C fires involve energized electrical equipment, and the recommended extinguishing agents are those that do not conduct electricity. Carbon dioxide (CO2), halons, and dry chemical extinguishers are particularly effective because they can smother the fire without introducing a conductive element or creating a shock hazard.

CO2 acts by displacing oxygen, thereby suffocating the fire, while halons work in a similar way but also interrupt the chemical reaction of combustion. Dry chemical agents effectively extinguish fires by interrupting the chemical chain reaction as well and are suitable for use on energized electrical equipment.

In contrast, water and sand can pose risks on a Class C fire. Water is a conductor of electricity, and using it could result in electrocution or worsen the fire. Aqueous film-forming foam is primarily used for Class B fires—those involving flammable liquids—and is also not suitable for Class C fires. Class B foam is used to suppress flammable liquid fires, but again, it doesn't address the unique properties of Class C fires effectively.