Fire Extinguisher for Electrical Fires: What You Need to Know
Fire Extinguisher for Electrical Fires: What You Need to Know
Electrical fires are one of the most dangerous types of fires because the presence of electricity adds the risk of electrocution to the danger of burns. Using the wrong extinguisher on an electrical fire can be deadly. This guide covers everything you need to know about selecting and using fire extinguishers for electrical fires, whether in your home, office, or industrial facility.
What Makes Electrical Fires Different
Electrical fires involve energized electrical equipment. The electricity flowing through the equipment creates unique hazards. First, the electric current can travel through conductive extinguishing agents and electrocute the person using the extinguisher. Second, electrical fires can arc or flash over, causing sudden explosions. Third, electrical equipment can remain energized even after visible flames are extinguished, creating a risk of re-ignition. Fourth, the smoke from electrical fires often contains toxic chemicals from burning insulation and circuit board materials. These factors make electrical fires particularly dangerous and require specialized extinguishing agents and techniques.
Safe Extinguishers for Electrical Fires
Only two types of fire extinguishers are safe for use on energized electrical equipment. CO2 (Carbon Dioxide) extinguishers are the preferred choice for electrical fires involving sensitive equipment. CO2 is a non-conductive gas that displaces oxygen around the fire. It leaves no residue, making it ideal for computers, servers, laboratory equipment, and expensive machinery. CO2 extinguishers are rated for Class C (electrical) and Class B (flammable liquid) fires. They are safe to use on live electrical equipment up to 1000 volts. However, CO2 extinguishers have a limited discharge range (1-2 meters) and are less effective outdoors or in windy conditions. Dry chemical powder (ABC) extinguishers are also safe for electrical fires. The powder is non-conductive and can handle fires involving live electrical equipment. ABC extinguishers have a longer discharge range (3-5 meters) and are effective on Class A, B, and C fires. However, the powder residue can damage sensitive electronics and requires extensive cleanup. For home electrical fires, an ABC extinguisher is usually the best choice. For offices and data centers, CO2 extinguishers are preferred.
NEVER Use These on Electrical Fires
Water extinguishers are extremely dangerous on electrical fires. Water conducts electricity and can cause severe or fatal electric shock. Never use a water extinguisher on any electrical equipment. Foam extinguishers also conduct electricity and should not be used on electrical fires. The foam solution creates a conductive path for electricity. Wet chemical extinguishers are designed for kitchen fires and are not safe for electrical fires. Even if the fire appears to be electrical but has spread to other materials, default to using a non-conductive extinguisher unless you are certain the power source is disconnected. When in doubt, use a CO2 or dry chemical extinguisher.
Safety Precautions for Electrical Fires
Before attempting to fight an electrical fire, follow these safety precautions. Attempt to disconnect the power source. If the fire involves a specific appliance, try to unplug it if the plug is accessible and safe to reach. If the fire is in the building wiring, turn off the main circuit breaker if you can access it safely. However, never risk your safety to disconnect power. If the power cannot be disconnected safely, use only a non-conductive extinguisher. Maintain a safe distance of at least 2 meters from the fire. Electrical fires can arc or flash, and the heat can be intense. Do not touch any metal parts of the equipment or enclosure while fighting the fire, as they may be energized. Stay away from water or wet areas that could conduct electricity. If the fire is in a wall cavity or ceiling, do not attempt to fight it yourself. Evacuate and call the fire department.
CO2 vs Dry Powder for Electrical Fires
When choosing between CO2 and dry powder for electrical fire protection, consider the following factors. For environments with sensitive electronic equipment like computer server rooms, data centers, telecommunications facilities, laboratories, and hospital equipment rooms, CO2 extinguishers are the best choice because they leave no residue that could damage equipment. For general electrical fire protection in homes, offices, and industrial settings, dry powder extinguishers are more versatile and cost-effective. They handle a wider range of fire classes and have a longer effective range. However, consider that dry powder residue can be corrosive to some metals and can cause short circuits in sensitive electronics. For comprehensive protection, many facilities keep both types - CO2 for sensitive equipment areas and dry powder for general electrical fire risks.
Fire Extinguisher Ratings for Electrical Fires
Electrical fires are classified as Class C fires. On fire extinguisher labels, look for the Class C rating symbol, which is typically a circle with a C inside or a plug and socket pictogram. The Class C rating is not numeric because it indicates that the extinguishing agent is non-conductive rather than quantifying the amount of fire it can handle. Any extinguisher with a Class C rating can be safely used on energized electrical equipment. Most ABC dry powder extinguishers include Class C in their rating. CO2 extinguishers are also rated for Class C. When purchasing an extinguisher for electrical fire protection, ensure the label clearly states it is suitable for Class C fires.
After the Fire Is Extinguished
After extinguishing an electrical fire, take these additional steps. Do not touch or move the equipment until it has been de-energized and cooled down. Assume all equipment involved in an electrical fire is damaged and may still be a shock hazard. Have a qualified electrician inspect the electrical system before restoring power. If a dry powder extinguisher was used, clean up the residue as soon as possible to prevent corrosion of metal surfaces and damage to electronic components. Replace or professionally service the used fire extinguisher. Document the incident for insurance and safety records.
Electrical fires require careful handling and the right equipment. Ensure your home and workplace are equipped with the appropriate fire extinguishers for electrical fire protection. Oust Fire supplies both CO2 and dry powder extinguishers rated for electrical fires, along with professional guidance on selection and placement.
Also read: Electrical Fire Prevention in Indian Homes and Types of Fire Extinguishers and Their Uses.
