An electrical fire involves energized electrical equipment or wiring and is classified by fire safety experts as a Class C fire. This type of fire presents an immediate danger because the electrical current continues to feed the fire and poses a severe shock hazard. Unlike fires involving ordinary combustibles, a Class C fire requires specialized response methods to prevent electrocution. The urgency centers on disabling the energy source that sustains the hazard.
Immediately Disconnect the Power Source
The first step in responding to an electrical fire is to de-energize the circuit. This eliminates the primary electrical danger and converts the Class C fire into a more manageable Class A or B fire. If the fire is small and originating from an appliance, safely unplugging the device is the quickest way to cut power, provided the outlet and cord are easily accessible and not engulfed in flames.
For fires involving built-in wiring, electrical panels, or large equipment, the power must be shut off at the main circuit breaker or the dedicated sub-panel breaker. Locate the electrical panel and use a dry hand to flip the appropriate breaker switch to the “Off” position. If the specific circuit cannot be identified, the safest course of action is to shut off the main power breaker for the entire building. Prioritizing safety means standing back from the fire and avoiding contact with any metal or wet surfaces while de-energizing the circuit.
Safe Fire Suppression Methods
Once the electrical current has been cut off, attention can turn to fire suppression, but only if the fire remains small and contained. The appropriate tool is a Class C or a multi-purpose Class ABC dry chemical fire extinguisher, which uses non-conductive agents. These extinguishers contain materials that interrupt the chemical reaction of the fire.
To use the extinguisher correctly, remember the PASS technique:
- Pull the pin.
- Aim the nozzle low at the base of the fire.
- Squeeze the handle to release the agent.
- Sweep the nozzle from side to side.
Maintain a safe distance of several feet while discharging the extinguisher to avoid heat and smoke. If the fire is growing rapidly, if the power cannot be disconnected safely, or if the flames spread beyond the initial object, immediate evacuation is mandatory. Prioritize personal safety, evacuate the premises, and call emergency services for professional assistance.
Understanding the Danger of Water
Water or any water-based extinguisher must never be used on an energized electrical fire. Water is a conductor of electricity, especially tap water due to its dissolved minerals and impurities. Applying a stream of water creates a conductive path that carries the electrical current from the fire source back to the person holding the hose or extinguisher.
This direct pathway places the individual at severe risk of electrical shock or electrocution. Even if the fire is small, the risk of injury from the energized circuit is high. Furthermore, using water on an electrical fire can cause the fire to spread by splashing burning materials or by creating steam explosion hazards. Therefore, non-conductive suppression agents are required to safely smother the flames.
Reducing the Risk of Electrical Fires
Preventing electrical fires involves regular maintenance and following safe usage guidelines for household devices and wiring. Overloading circuits is a common cause, occurring when too many high-wattage appliances are plugged into a single outlet or circuit. While power strips are acceptable temporary solutions, extension cords should never be used as a permanent substitute for proper wall outlets.
Periodically inspect power cords and appliances for signs of wear, such as frayed insulation, cracking, or discoloration, and replace damaged items immediately. Ensure that heat-generating appliances, such as space heaters, have appropriate clearance from flammable materials like curtains or furniture. Installing arc-fault circuit interrupters (AFCIs) in your electrical panel provides added protection by detecting dangerous electrical arcs and quickly shutting off the power.