Wondering if it is safe to use a fire extinguisher on an electric fire? The short answer is yes, if you are using the right kind of fire extinguisher and if you have turned off the electricity.
With increasing news coverage on residential fires related to malfunctioning electric bike chargers, it’s no wonder we have been getting more queries about whether it is safe to use fire extinguishers on electric fires.
To help improve fire safety awareness amongst our clients and the average Singaporean we have written an educational article to shed light on the right way to approach electric fires. Read on to learn more!
What is an electrical fire?
Electricity is usually a source of ignition for electric fires (Class E fires). They tend to occur because of overloading, faulty circuits, worn-out outlets, damaged, or non-compliant electrical appliances.
What makes electric fires so dangerous? The fact that there is a live current running through the ignition source and fire makes it extremely dangerous to combat it with water or water-based extinguishers that could conduct electricity.
Turn off the electricity before fighting fires
The good news is most of the time, electric fires are simply Class A (fire involving solids) combustibles that have been ignited from the heat coming from an electricity source. Remove that electricity source and we have a Class A fire that is easier to combat.
The most important thing to remember? Before attempting to fight any electric fire, the first step is to quickly turn off the electricity. The main reason for this is to cut the electric current flow to prevent electrocution and to prevent re-ignition. If the electricity is still generating heat, the fire can easily re-ignite.
However, if you are unable to safely cut the power to the appliance, then do not attempt to combat the fire on your own and leave it to the professionals.
Where did the fire extinguisher’s Class C and Class E logo go?
To help with identifying which type of fire extinguishers are suitable for which type of fire, there are logos on the extinguishers indicating so.
In Singapore, the Class C logo is used to represent gas fires while the Class E logo represents electric fires. Note this classification may differ from country to country e.g. In America, Class C represents electric fires instead.
Due to potential confusion, Class C and Class E logos have been phased out from the current Singapore Standards since the 2012 edition. Instead, they have been replaced which much clearer phrases to indicate if it is suitable for use on an electric fire:
- “Use with care on live electrical equipment”
- “Suitable for use on live electrical equipment up to 1000v at a distance of 1m”
If you still see the Class C or Class E logo on your fire extinguisher, they are at least 10 years old and likely not in operable condition any longer. We urge you to replace these fire extinguishers as soon as possible.
However, regardless of Class C or Class E fires, SCDF recommends that the source of fire be turned off as soon as it is safe to do so. This means turning off the gas supply or electricity. This is because both types of fire will quickly reignite if the source is not turned off.
Powder fire extinguishers are safe to use on electric fires
Generally speaking, dry powder is a poor conductor of electricity. This makes it one of the best options to fight electric fires compared to water.
Therefore, in situations where the fire is blocking access to turn off the electricity, dry powder fire extinguishers are the safest choice to fight electric fires.
Having said that, one should always take precautions when firefighting.
Being a “poor conductor of electricity” does not mean dry powder will not conduct electricity at all. At very high voltages and close distances, it is still possible to be electrocuted – an example would be cases of lightning strikes occurring even though air is a very poor conductor of electricity.
Singapore Standards EN3 Fire Extinguisher Dielectric Test
Are dry powder extinguishers the only option then for electric fires? The answer is no! Water-based fire extinguishers that have passed the dielectric test successfully are also a good and safe alternative.
All Hercules water based fire extinguishers have successfully passed the dielectric test, making them suitable for fighting electric fires.
The reason for not allowing water-based fire extinguishers was because firefighters might unknowingly, accidentally discharge a fire extinguisher at a live electric current resulting in electrocution.
To get around this issue, the dielectric test was created to ensure that even if the firefighter did accidentally discharge the fire extinguisher onto a live electric fire, he or she would still be reasonably safe.
Here’s what happens in a dielectric test:
- A live voltage is set up to test the possibility of the fire extinguisher being electrified upon direct discharge.
- A rectangular metal plate is placed at a distance of 1m from the fire extinguisher.
- Upon discharge, if the circuit is closed and the ammeter detects a live current, the test is considered to have failed. If no current is detected, the test would be considered to be successful.
Do note that this test is conducted under safe conditions in a sterile laboratory under professional supervision. Do not try this at home.
Water-based fire extinguishers that successfully pass this test would have the label “Suitable for use on live electrical equipment up to 1000v at a distance of 1m” accordingly.
Use with care for live electrical equipment
Whether you are using a powder or water based fire extinguisher on live electrical equipment, it should be done with caution. Similar words will also appear on a powder fire extinguisher’s instruction label.
Realistically speaking, during fire fighting, nobody would be trying to measure the current with an ammeter amidst the chaos. How would anyone know if the current is up to 1000v? Just like a lightning strike, if the potential difference is great enough, even air is a conductor for electricity. This is why, the number one rule for fighting live electrical fires starts with turning off the electricity. We want to keep ourselves as safe as possible and reduce the risk of being electrified.
Prevent electrical fires by maintaining your electronic equipment regularly
Apart from learning how to combat electrical fire, why not go one step further to prevent it from even happening in the first place? After all, prevention is better than a cure.
Old electrical appliances have a higher probability of starting electrical fires due to aging components. From worn-out safety components, exposed wiring, and more, you can avoid an electrical fire starting in the first place by replacing these damaged components regularly.
Maintenance of electronic appliances aside, another way to prevent electrical fires is to practice good habits like avoiding overloading power sockets, using only Singapore Mark-certified electronic appliances, keeping combustible items away from electrical outlets, and more.
Remember, the best way of fighting an electric fire is not to let it happen in the first place.
Equip Your Home or Workplace with The Right Type of Fire Extinguishers Today!
Now that you’re aware of the different types of fires and corresponding types of fire extinguishers to combat them, the next important question is “Do you have the appropriate type of fire extinguishers in your home and workplace?”
At Fire Armour, we offer the complete range of fire extinguishers for all types of emergencies you can anticipate. From dry power types, foam types, and carbon dioxide types to clean agent fire extinguishers we have it all!
Shop conveniently online via our new e-commerce shop, or if you have any queries, simply reach out to our friendly team via live chat to learn more about our offerings.