Whilst all the other fire classes use a letter to identify them, Class E is not the term used for Electrical Fires, instead, they are simply classed using their name.
Electrical fires are not given a class of their own as they can be a little complex in their cause and behaviour. Often an electrical fire involves other classes of fire as well so it’s one of the more tricky types to deal with.
As with all fire types, electrical fires need 3 elements to cause ignition which are heat, oxygen, and electricity. This means they need to be controlled carefully in a way so as not to worsen the flames.
To keep everyone in the work environment safe, it is imperative to have sound knowledge of fire extinguishers. Electrical fires can be extremely dangerous and need to be tackled appropriately.
What Is An Electrical Fire?
Electrical fires involve equipment igniting such as computers, televisions, hair dryers, microwaves, refrigerators and freezers.
This type of fire often rolls over into more than one category which is why it doesn’t have a full class of its own. To put that in simple terms, when a spark in an electrical item ignites, the whole piece of equipment goes on fire.
A very common cause of fire both commercially and domestically, electrical fires can cause extensive damage. They can be caused by something simple as an appliance overheating or being faulty. In this day and age with so much technology at our fingertips, it is not surprising they are the cause of many fires.
Fires caused by electricity can begin in almost any environment you can think of. Offices, schools, hospitals, factories, and restaurants are just a few that can be named. All it takes is a faulty connection or something left on to overheat to begin a fire.
Fire Symbol
For any fires of an electrical nature, you will see the letter E and underneath an image of a socket and a spark.
See Also: Fire Extinguisher Colours & Uses – a guide to the different extinguisher label colours and what fire types they are used on.
About Electrical Fire Extinguishers
Using the incorrect fire extinguisher on an electrical source can have dire consequences including possible electrocution. You need to use either a dry powder or CO² fire extinguisher for electrical fires.
Both dry powder and CO² extinguishers are safe to use on electrical equipment. They set to work by diminishing the oxygen supply which is needed to keep the fire going. If the fire is fairly small, then a fire blanket is another viable option. The most important step to take when dealing with anything electrical is to turn off the power source if it is safe to do so.
You must never throw or spray water onto an electrical fire. This is because water is a natural conductor of electricity and can intensify the situation or cause an electric shock.
Our guide on fire extinguishers for electrical fires has more detailed information.
Dry Powder Fire Extinguishers
You can use a dry powder extinguisher on an electrical fire.
These work by counteracting the chemical reaction that is taking place within the fire and reducing the oxygen available. The powder used is called mono ammonium phosphate and it also reduces the heat intensity. They are safe to use on fires involving solid combustibles and flammable liquids but should be avoided in small, enclosed spaces.
CO² Fire Extinguishers
CO² fire extinguishers are another safe option in the event of an electrical fire in your vicinity.
The gas in a CO² canister is heavier than oxygen. This means that by releasing it onto the fire, the carbon dioxide replaces the oxygen as the dominant source.
Oxygen is required to keep the electrical fire burning so it will go out without this. CO² extinguishers are also very effective in dealing with flammable liquids (Class B fires).
How to Extinguish an Electrical Fire?
An electrical fire is fuelled by heat, oxygen and electricity and all 3 of these are required for the fire to be ignited and stay ignited.
When one of these elements is taken away, the fire cannot continue to burn. Both powder and CO² extinguishers tackle the oxygen supply that is keeping the fire ignited. Their purpose is to eradicate the oxygen which is fuelling the fire.
Before you tackle an electrical fire, you need to try and turn off the power supply if it is safe to do so. Do not put yourself or others in danger doing so though, if the situation is unsafe then call the fire services instead.
How to Use a Dry Powder and CO² Extinguisher
When using a dry powder or CO² fire extinguisher on an electrical fire you should firstly turn off the power supply. If you cannot do this safely then instead call the fire brigade.
A dry powder and CO² extinguisher need to be used in a safe and controlled manner.
Once the powder or carbon dioxide is discharged, visibility can be impaired, particularly if it is used inside a building. Any people in the room should also try to breathe through their noses where possible. This is because the powder can act as an irritant, causing breathing issues.
- Get hold of the extinguisher and release the safety pin.
- Make sure to stand at a safe distance.
- Point the nozzle to the base of the fire and move in a horizontal direction.
- Keep going until the foam has smothered the fire.
The fire should be observed for any signs of reignition until you are positive it has been put out permanently.
Types of Extinguishers That Should Not Be Used
Any water fire extinguishers should never be used on an electrical based fire. Water will intensify the fire and only make it worse.
It is also highly likely that someone will be electrocuted when water is mixed with electricity.
Foam extinguishers also need to be avoided when it comes to electrical fires as they will also intensify the existing situation. They are meant purely for fires involving flammable liquids.
Electrical Fire Prevention
With electrical fires being so common, there are important precautions you can take to keep the risk to a minimum.
- Regularly check all electrical equipment for faults.
- Have any broken equipment professionally fixed or replaced.
- Make sure plugs aren’t loose or badly fitted.
- Cables should be intact with no frayed sections.
- Unplug appliances when they are not being used.
- Do not overload plug sockets.
- Regularly clean and check appliances.
- Check all appliances have the British or European safety stamp.
- Never leave equipment to charge when there is no one there, e.g. overnight.
