To extinguish a Class Charlie fire, what should be done first?

To effectively extinguish a Class Charlie fire, which involves electrical equipment, the first crucial step is to secure power. This action is vital because Class Charlie fires can be highly dangerous due to the presence of live electrical sources. If water or foam is applied without first ensuring that the electrical source is de-energized, there is a significant risk of electric shock to the person trying to extinguish the fire and possible further igniting or spreading the fire.

Securing power eliminates the source of the fire and allows for safer firefighting measures to be implemented afterward. Other methods, like applying water or chemical agents, must only be conducted after ensuring that the electricity has been turned off, as these methods are inappropriate and can exacerbate the situation when electrical components are still live. Thus, prioritizing the safe termination of electrical power is both a safety measure and a critical step toward effectively managing the fire risk associated with electrical equipment.