Having the right types of
fire extinguisher at your business premises is essential to meet your health and safety obligations (
The Regulatory Reform (Fire Safety) Order 2005). However, with several categories of extinguisher, it can be confusing knowing which ones you need.
The reason for the complexity is that there are six different types of fire:
- Class A - fires involving flammable solids (e.g. wood, paper, and fabric).
- Class B - fires involving flammable liquids (e.g. petrol, diesel, paint or oils).
- Class C - fires involving flammable gases (e.g. hydrogen, butane or methane).
- Class D - fires involving combustible metals (e.g. magnesium, aluminium or potassium).
- Electrical - fires involving electrical equipment. Following removal of the electrical item, the fire changes class according to the combustible material involved.
- Class F - fires involving cooking oils (e.g. chip-pans).
Unfortunately, there is not one fire extinguisher which works on all classes of fire hence five different types. These are:
- Water
- Foam
- Dry powder
- CO2
- Wet chemical
Let’s look at each of them in a little more detail.
Types of fire extinguishers
1. Water
Water extinguishers are the most common and cost-effective extinguisher type for class A fires. They have a red label and can be a jet, spray or mist extinguisher.
You mustn't use a water extinguisher on fires involving electrical equipment or flammable gas and liquids, or kitchen fires.
2. Foam
Foam extinguishers are the most common type of fire extinguisher for Class B fires. However, being water-based, they also work on Class A fires.
Foam extinguishers have a cream label. They’re not suitable for use on kitchen fires and fires involving electrical equipment or flammable metals.
3. Dry powder
Powder extinguishers are suitable for Class A, B and C fires. However, they’re not recommended for use in enclosed spaces as they can reduce visibility and cause breathing problems from inhalation.
Powder extinguishers have a blue label and must not be used on fires involving cooking oil or electrical equipment over 1000v.
4. CO2
The primary use of carbon dioxide (CO2) extinguishers is for electrical fire risks. They can also be used on Class B fires involving flammable liquids such as paraffin or petrol.
CO2 extinguishers have a black label and are not suitable for kitchen fires (especially chip-pan fires), and fires involving combustible materials or flammable metals.
5. Wet chemical
The final type of fire extinguisher, wet chemical, are designed for use on Class F fires, involving cooking oils and fats. They can also be used on Class A fires if necessary.
Wet chemical extinguishers have a yellow label. They’re not to be used on flammable liquid or gas fires, electrical fires and fires involving flammable metals.
Which fire extinguishers?
Current UK fire extinguisher regulations (August 2020) state that you should have a minimum of two Class A extinguishers on every storey of your building. Whether you need any other type of fire extinguisher will depend on the fire risk from the different classes of fire at your premises.
As well as having the right kind of extinguishers, you must also ensure that you have the right size and weight of fire extinguisher.
If you’re unsure which fire extinguishers you need, please give us a call on 01392 368830 or drop us an
email. We’ll complete a survey of your premises and provide an assessment of your fire extinguisher requirements.
