Fire Extinguishers for Electrical Equipment

What is Di-electric Testing?

Di-electrical testing verifies that even with an incredibly high voltage of 35,000 Volt, no electrical current can flow back to the person discharging the extinguisher on a fire involving live electricity. The test consists of certain test distances between the user and the fire.

Once an extinguisher has passed this stringent test, it is still limited for safety reasons. The limits, which are found on electrically safe extinguishers, are a maximum of 1000 Volt and a minimum distance between the extinguisher and the fire of 1 metre (1000V is four times the voltage used in a domestic premises).

If a liquid extinguishing agent is used on a fire involving live electrical equipment, there is still a risk of a pool forming. The risk of electrocution for the user is reintroduced and increased if they were to stand in the pool. However, it is key to remember that the use of any liquid on live electrical equipment usually leads to immediate fuse-triggering and power is cut off to the electrical device.

Our range of dry water mist extinguishers, although a liquid based extinguishing agent, discharges de-ionised water in an extremely fine mist by a specially designed spray nozzle. Pooling is almost impossible by this method, and de-ionised water cannot carry an electrical current which reduces the risk of electrocution even further with minimum damage to the equipment.

What is an Electrical Fire?

Technically, there is no such thing as an electrical fire, as electricity itself does not burn and neither do the cable cores and other conductors. However, the electrical current can heat up other materials that may be on top of the cables or around the plug sockets, and this would be the start of what is considered to be an electrical fire.

Often, it is the cable covering or even foreign bodies in the electrical equipment that start to burn first. If the electrical supply to the equipment on fire continues, this is what is considered to be a fire involving live electrical equipment. The use of, for example, a simple water extinguisher could then lead to electrocution of the individual fighting the fire.

Therefore, when planning for extinguishers and what types you may require for your business or home, you must consider all risks, including what electrical equipment you may have to use, such as, laptops, printers, kettles, or washing machines.

Our section of electrically safe extinguishers will help you select a suitable extinguisher for your building or application.

What Extinguishers are Suitable for Live Electrical Equipment?

Historically and traditionally, CO2 fire extinguishers have been the number one choice for fire risks involving electrical equipment, as the gas extinguishing agent does not carry electricity. However, unless contained, CO2 gas can drift off and disperse quickly and the fire can re-ignite.

Powder extinguishers have also been known to be used on these types of fires, as they are powerful and do not conduct electricity. However, powder extinguishers are not recommended for use indoors any longer, as they can cause inhalation issues and impair the visibility of the escape route.

Newer types of extinguishing agents, such as water mist and eco-foams, have been developed in such a manner to overcome traditional solutions and provide an environmentally safe alternative.

Water Mist extinguishers have been specially developed to provide effective fire-fighting capabilities with little to no damage to property. With de-ionised water and a specially designed spray nozzle discharging a very fine mist blanket, this extinguisher does not create pools of liquid when tackling a fire, further protecting the user from both the fire and subsequent electrocution.

Eco-foams, a more recent developed extinguishing agent which overcomes the discontinuation of AFFF foams, has been developed to provide a solution to most fire classes including electrical. The extinguishing agent is free from harmful PFAS chemicals, making it a more environmental choice, as well as having high ratings for other fire classes.