Electrical fires are a real thorn in the side of fire safety. They are a potent and common threat, liable to occur wherever there is a density of electrical sources or systems. What’s worse is that they possibly have the fewest reliable ways to deal with them out of any fire classification.
Where we come in is on that last point. Carbon Dioxide, or CO2 Fire Extinguishers, are the only type rated for use on electrical fires. In this regard, we can provide you with the means to tackle these fires effectively and without damaging your electrics.
The Causes of Electrical Fires
Firstly, a quick note on classification. You may see information out there that gives electrical fires a lettered rating. In the UK, this would be incorrect. The European system previously assigned electrical fires to the Class E category, but they are unclassified as of current. But now that that’s out of the way, let’s talk about what causes these things.
Faulty equipment is a leading cause of electrical fires, and we’re not necessarily talking about stuff being put together badly. Electrics can be faulty due to loose or corroded connections and deteriorated insulation. These conditions can simply occur over time, but they must still be seriously considered when thinking about fire safety. Of course, risks can be increased by poor implementation as well. Improperly installed extension cords, overloading a power strip with connections, and using bulbs beyond the recommended wattage can all contribute.
There are also a few heat-oriented causes to keep in mind. A simple excess of heat can easily lead to an electrical fire. Just about anything that is poorly maintained or malfunctioning poses a risk, but kitchen appliances and heating or cooling systems are particularly vulnerable. The other side of this is proximity to heat sources and or/potential fuel sources. Devices near each other that produce a lot of heat aren’t going to do each other any good, and having combustible materials such as paper and fabric near high-heat or faulty devices will increase the risk of fire substantially.
What Makes Electrical Fires So Dangerous?
Electrical fires have unfavourable reactions to common extinguishing agents (aside from CO2), and they burn differently to other fires. Together, these factors create a nasty kind of blaze. As such, there’s a reason why water fire extinguishers and CO2 fire extinguishers are often considered a perfect pairing. As mentioned above, CO2 extinguishers are the only kind rated for use against electrical fires, while water ones are the last type you would use against them.
So what’s so bad about using water on electrical fires? Water is a natural conductor of electricity (I probably don’t need to say much more than that, really). This means that if you spray water onto an electrical fire, there’s a huge chance of you getting shocked or electrocuted. These same issues can be observed in Foam Fire Extinguishers. In terms of composition, the foam used is only a few steps away from water, and as such is conductive in the same, potentially dangerous way.
Powder is another common extinguishant that can actually be used on electrical fires. Most powder extinguishers are capable of this, but they will corrode the device, likely destroying the electrical components. Powder is also not recommended for internal use, so you need something safe to use inside that won’t cause further damage to the device. This is something we’ll discuss further when we get to CO2 extinguishers specifically.
Electrical Fire Prevention Advice
Perhaps I should go over some measures you can take, both for preventing electrical fires and tackling them. Let’s start with prevention:
- Keep areas around sockets and mains outlets as clear as possible
- Always use the right fuses for your plugs
- Never use damaged wires and plugs
- Never put electric cables under carpets
- Don’t overload power strips
- Avoid using broken or faulty electrical devices
- Switch off devices at the wall/pull plug out (I’m not trying to nag, but this is the only way to completely halt the electricity)
- Have appliances serviced annually to ensure they meet guidelines
That’s a fairly abbreviated list, there are definitely more steps you can take. But, we must now turn our attention actually combating electrical fires, both in list form now, and for the rest of this article:
- NEVER use water to put out electrical fires
- Immediately alert everyone in the building or area about the fire
- If it is safe to do so (aka: the fire has just barely started), you may be able to pull the plug or switch the power off at the fuse, potentially stopping the fire before it starts.
You should only take the following steps if you’ve already stopped the flow of electricity, and have deemed the fire safe to tackle:
- Try and cut off the oxygen source. If it is a small fire, a fire blanket is an effective way to do this.
- If you’re sure the electricity has been cut off completely, it may be safe to use a foam or water extinguisher as it is now a normal fire, but if there’s any doubt then just use a CO2
- For a larger (but still safe to tackle, which is to say, not big) fire, use a CO2 extinguisher to try to put it out directly
How CO2 Extinguishers Tackle Electrical Fires
Electrical fires achieve their infamous status by upending the typical way that fires behave. The fuel source of the fire cannot be effectively smothered through traditional means, so it is very difficult to cut the fire off from its oxygen supply. CO2 extinguishers counter this aspect of electrical fires directly, hence why they are specialised for the job.
Due to the storage pressure, the CO2 resides in liquid form when inside the extinguisher. But, when the pressure is released the CO2 quickly turns back into gas and is discharged from the extinguisher. Then, given that CO2 is heavier than oxygen, it displaces the oxygen surrounding the fire. This starves the fire much like when we might use a powder or foam to create a direct barrier between the fuel source and the air.
CO2 extinguishers can put out electrical fires without causing any further damage to the device. This is due to CO2’s dryness, which leaves behind no residue that could affect the operation of electrical equipment. Also, just in case it needed to be said: CO2 is non-conductive, so using it on electrical fires doesn’t present any extraneous dangers.
The Other Cans and Cannots of CO2 Extinguishers
While electrical fires are the speciality of CO2 extinguishers, that’s only one of two fire classifications they are built for. Class B fires are those involving flammable liquids such as petrol. These are the most common types of fire found in places like petrol stations and garages. In these contexts, CO2 extinguishers are often paired with foam fire extinguishers, providing impressive coverage that includes Class A, B, C and electrical fires. This combination is also highly likely to help you meet safety regulations without the need for any other extinguisher types.
You may now be thinking that CO2 extinguishers would be right at home in a kitchen. They’re prone to electrical fires, and are probably equally liable to flammable liquid fires, so why not? Well, that’s because cooking oil fires aren’t Class Bs. We’ve already discussed that that classification is for liquid fires, but this is a detrimental exception.
Grease fires are Class Fs, and, while technically a subclass of both liquid and gas fires, neither foam nor CO2 are appropriate for tackling them. This is what you need a Wet Chemical Fire Extinguisher for: a highly specialised type that, as might be expected, cannot be used on Class Bs.
But, all that doesn’t change the fact that CO2s give you reliable protection against Class B fires, and are pretty much the only sure-fire way to secure yourself against electrical fires. So if you have concerns about electrical fires, then make sure to follow as much of the advice listed above as you can, and feel free to browse our range of CO2 Fire Extinguishers here. And, if that’s not enough, you can check out this helpful explanation video for more information:
