Understanding Electrical Fires
Key Takeaways:
- CO₂ extinguishers are best for electrical fires.
- Water-based extinguishers must never be used on live electrical equipment.
- Electrical fires are often caused by overloaded circuits or faulty devices.
- Regular maintenance and proper extinguisher placement are essential.
- Staff should be trained on the correct extinguisher type and usage.
What Is an Electrical Fire?
An electrical fire originates from electrical faults, such as short circuits, overloaded circuits, or faulty wiring. Unlike fires involving solid combustibles (Class A) or flammable liquids (Class B), electrical fires involve live electrical equipment, making water-based extinguishers unsafe. Over a three-year period, there were 4,634 callouts for electrical-related fires in UK businesses. Notably, December experiences the highest number of such fires, averaging 1,053 callouts, likely due to increased use of electrical decorations, heating appliances, and overloaded fire alarms during the festive season.
Why Using the Wrong Extinguisher Is Dangerous
Using the wrong extinguisher on an electrical fire can result in electrocution or further fire spread. Water and foam conduct electricity, increasing the risk of shock. Some extinguishers can damage electrical equipment or create toxic fumes when used improperly.
Recommended Fire Extinguishers for Electrical Fires
CO₂ (Carbon Dioxide) Fire Extinguishers
CO₂ extinguishers work by displacing oxygen, effectively suffocating the fire. They are ideal for electrical fires because:
- No Residue: CO₂ evaporates completely, leaving equipment undamaged.
- Non-Conductive: Safe for use on live electrical circuits.
Precautions:
- Maintain a safe distance to avoid exposure to CO₂ gas.
- Do not touch the discharge horn, as it becomes extremely cold and can cause frostbite.
- Use in well-ventilated areas to prevent suffocation from CO₂ buildup.
Dry Powder Fire Extinguishers
Dry powder extinguishers smother flames by interrupting the fire’s chemical reaction and cutting off its oxygen supply. They are suitable for Class C (electrical) fires and also work on Class A and B fires.
Advantages:
- Effective on various fire types.
- Non-conductive, making it safe for electrical fires.
Downsides:
- Leaves a fine powder residue that can damage electronics.
- Can reduce visibility when discharged in enclosed spaces.
Fire Extinguishers to Avoid for Electrical Fires
Unsafe Extinguishers for Electrical Fires
- Water Extinguishers: Conduct electricity, causing shock hazards.
- Foam Extinguishers: Can be conductive if the foam contains water.
- Wet Chemical Extinguishers: Designed for grease fires, not electrical ones.
Exceptions
Some dielectric-tested foam extinguishers are safe for electrical fires up to 1,000V. However, always check manufacturer guidelines before use.
Using a Fire Extinguisher Safely on Electrical Fires
Steps to Take Before Using an Extinguisher
- Turn Off the Power: If safe to do so, disconnect electricity to prevent reignition.
- Ensure Personal Safety: Stand at a safe distance to avoid smoke or electrical hazards.
- Use the Right Extinguisher: Confirm it’s suitable for electrical fires before use.
Correct Extinguisher Usage Technique
The PASS Method ensures proper extinguisher operation:
- Pull the safety pin.
- Aim at the fire’s base.
- Squeeze the handle to discharge.
- Sweep side to side until the fire is out.
Additional Tips:
- When using CO₂ extinguishers, avoid touching the horn due to extreme cold.
- Direct the extinguisher’s discharge at the fire’s base for maximum effectiveness.
Fire Prevention and Safety Tips for Electrical Fires
- Regular Maintenance: Inspect electrical equipment for wear and overheating.
- Avoid Overloaded Circuits: Do not plug too many devices into one outlet.
- Check Wiring: Replace frayed or damaged wires immediately.
- Keep Extinguishers Accessible: Place CO₂ or dry powder extinguishers near high-risk areas like server rooms or workshops.
Proper fire extinguisher selection and usage can prevent extensive damage and ensure safety in case of an electrical fire.
Q: What type of fire extinguisher is suitable for electrical fire use?
A: The best type of fire extinguisher for electrical fires is a CO2 fire extinguisher, as it is safe to use on live electrical equipment and does not leave any residue that could damage equipment.
Q: Can water fire extinguishers be used on electrical fires?
A: No, water fire extinguishers cannot be used on electrical fires as they can conduct electricity and create a risk of shock. It is recommended to use CO2 extinguishers or dry powder extinguishers instead for Class A fires.
Q: What class of fire can CO2 extinguishers tackle?
A: CO2 extinguishers are effective on Class B fires (flammable liquids) and Class C fires (gases). They are also ideal for use on electrical fires involving live electrical equipment up to 1000 volts.
Q: Are water mist extinguishers safe to use on electrical fires?
A: Yes, water mist extinguishers can be safe to use on electrical fires as they produce a fine mist that cools the fire without conducting electricity, making them suitable for tackling live electrical equipment.
Q: What should you do if you encounter a fire involving electrical equipment?
A: If you encounter a fire involving electrical equipment, you should ensure your safety first and then use a suitable fire extinguisher, such as a CO2 or dry powder extinguisher, to tackle the fire.
Q: What is the importance of knowing the different types of fires?
A: Knowing the different types of fires and their corresponding classes is crucial for selecting the right type of fire extinguisher. This ensures effective fire suppression and minimizes the risk of injury or further damage.
Q: How do I know which type of extinguisher to use?
A: To determine which type of extinguisher to use, assess the source of the fire. If it involves electrical equipment, a CO2 extinguisher or dry powder extinguisher is recommended. Fire alarm systems can also help identify the location and type of fire, aiding in a quicker, more effective response. Always consult fire safety guidelines for specific recommendations.
