Which fire extinguisher is typically not suitable for use on live electrical equipment?

Water extinguishers are typically not suitable for use on live electrical equipment due to the conductive properties of water. When water is used on electrical fires, it can complete the circuit and potentially lead to serious electrocution hazards for anyone nearby. Electrical fires can arise from faulty wiring, overloaded circuits, or equipment malfunction, and using water in these situations can exacerbate risks rather than mitigate them.

In contrast, carbon dioxide extinguishers, dry chemical extinguishers, and foam extinguishers can effectively handle electrical fires without the risk of conducting electricity. Carbon dioxide works by displacing oxygen, thus suffocating the fire, while dry chemical extinguishers disrupt the chemical reaction of the fire. Foam extinguishers can be used for flammable liquids, but caution is required, and they should only be used on electrical fires that are confirmed to be safe for such applications.