One question we are often asked during fire safety training is “What are the different types of fire extinguishers used for?” In this article, we answer this question and also explain what the different classes of fire are.
The short answer is that is depends upon the type of fire you are dealing with, or to put it more correctly the class of fire.
So, what are the different classes of fire?
The class of fire depends upon the fuel that starts the fire. In the UK there are five recognised classes of fire:
- A fires caused by organic solids like paper, wood, etc
- B fires caused by flammable liquids
- C fires caused by flammable gasses
- D fires caused by burning metals (e.g. aluminium swarf)
- F fires caused by fats, such as those used in deep fat fryers
What about Class E fires, aren’t they electrical fires?
Class E does not exist as electricity is a source of ignition rather than a fuel. Once the electricity starts the fire it is the surrounding material that burns, not the electrical current. The first step when fighting a fire caused by electricity is to switch the equipment off. Once the electrical supply has been removed, the fire will then fall into one of the five classes listed above.
In our Fire Safety Courses, we talk about the different types of extinguishes.
Does that mean that I can use a water extinguisher on an electrical fire?
Technically yes, although any water-based extinguishers used on electrical equipment should be dielectrically tested and certified to ensure that you can extinguish the fire safely, even if the power supply is left on. It must be remembered that certain electrical apparatus retain charge for some time after they have been switched off.
Which fire extinguishers can I use for each class of fire?
There are five main types of extinguisher, the list below states the type along with the class of fire they can be used on:
- Water Class A
- Foam Class A and B
- Dry powder Class A, B, C and D
- Carbon dioxide Class B (many organisations use these on “electrical” fires as well)
- Wet chemical Class A and F
How can I tell the difference between each type of extinguisher?
All fire extinguishers are now coloured red and you need to look at the label to determine which type of extinguisher it is. The colour coding is as follows:
- Water Red
- Foam Cream
- Dry powder Blue
- Carbon dioxide Black (only extinguisher with a funnel on the delivery hose)
- Wet chemical Yellow
Envesca offers two levels of fire courses, both of which offer advice and guidance on Fire Extinguishers.