Different Types of Fire Extinguisher and How to Use Them
Posted by Rob Sherman – Fire Safety Director
Fire extinguishers are vital to fire safety in the workplace. This guide outlines the different types of fire extinguisher and when and how to use them.
In 2016-17 there were 19,410 fires reported to fire and rescue services at UK businesses, 13,892 of which were accidental and 5,518 were started deliberately.
The impact of a fire in the workplace can be devastating. Employees can face physical and emotional effects, and companies risk significant loss of data, equipment and finances. Estimates put the average cost of a fire in a commercial building at £58,100.
Different types of fire bring different risks, so it’s essential that you minimise the chances of a fire and are prepared should the worst happen.
Employers face a fine or prison for not following fire safety regulations.
They are required by law to provide fire safety information to employees, understand the legal requirements for fire extinguishers in the workplace and carry out a fire risk assessment.
The assessment will help you decide on the type and number of fire extinguishers that are required for your company.
While not all companies are required to have fire wardens – a role that is responsible for sweeping a building during an evacuation – it is a good idea to ensure that all staff understand the different types of fire extinguisher in the workplace, and how and when to use one.
The type of fire extinguisher that should be used is dependent on the class of fire. Using the wrong type of extinguisher can cause more harm than good, so it’s essential to identify the source of fuel for a fire before attempting to tackle it.
The categories of fire in the UK and Europe are:
• Class A – solid materials such as wood, paper or textiles.
• Class B – flammable liquids such as petrol, diesel or paint.
• Class C – flammable gases such as propane, butane or methane.
• Class D – metals such as magnesium, titanium or aluminium.
• Electrical – live electrical equipment such as computers and televisions. (Not recognised as a separate class of fire in Europe but a type you need to look out for).
• Class F – cooking oils such as vegetable oil, olive oil or butter (typically used for deep-fat fryers).
There are five main types of fire extinguishers:
Each type can be identified by the text and colours of the label, and in some cases by their hoses.
Each type of fire extinguisher contains a different extinguishing agent that makes them suitable for tackling certain types of fires. Selecting the right fire extinguisher is essential otherwise they may have no effect or aggravate the fire, making it worse.
Here’s a guide to each type of fire extinguisher, the type of fires they should be used on and when not to use them.
This type of fire extinguisher is red with the word ‘water’ in white text.
Use: Water extinguishers dispense water at high pressure and should only be used to tackle class A fires involving solid materials such as paper, wood, plastics and coal.
Water spray: Water spray extinguishers, which spray water over a bigger area, are red with ‘aqua spray’ in white text. They are also only suitable for class A fires.
Warning: Do not use water and water spray extinguishers on fires involving burning fat, oil and electrical appliances.
This type of fire extinguisher is red and has the words ‘water mist’ in red text on a white label.
Use: Dry water mist can be used on class A, B, C and F fires. They can be used on live electricity up to 1,000 volts.
Powder fire extinguishers, which release powder to smother the fire, are red with ‘powder’ in white text on a blue label. Underneath the blue label is ‘ABC powder’.
Use: They can be used for class A, B and C fires. They can also be used for electrical fires but because they don’t cool the fire, it could re-ignite.
Warning: Do not use powder extinguishers on class F fires involving cooking oils.
Powder extinguishers can be messy, cause breathing problems, reduce visibility and damage equipment. They should not be used in confined spaces unless mitigated by a health and safety risk assessment.
M28 and L2 are special types of powder extinguishers. They also have ‘powder’ in white text on a blue label, but underneath the label it says M28 or L2. M28 and L2 operate differently to other extinguishers so separate training should be provided.
Use: They are designed for class D fires involving metals. L2 extinguishers can be used on all types of metal fires, but M28 extinguishers cannot be used on fires involving lithium.
Warning: Do not use M28 and L2 extinguishers to tackle any other type of fire.
This type of fire extinguisher is red with ‘foam’ in red text on a cream label. Like powder extinguishers, the foam smothers the fire to put it out.
Use: They can be used on class A and B fires.
Warning: Foam extinguishers contain water so they should not be used on or near electrical equipment.
Carbon dioxide extinguishers are red with ‘CO2’ in white text on a black label. They have a large cone at the end of the hose which is different from other extinguisher hoses. Do not hold the cone as it could freeze your skin. Frost-free cones are available.
Use: They can be used on class B and Electrical fires.
Warning: Do not use carbon dioxide extinguishers on class F fires involving cooking oils.
Wet chemical fire extinguishers are red with ‘wet chemical’ in red text on a yellow label.
Use: They are used for class F fires. When operated, a soap-like chemical is released as a spray which stops the flames and cools the oil. This type can also be used to tackle class A fires, but they are not as effective as water extinguishers.
Warning: Do not use wet chemical extinguishers on class B and C fires involving liquids and gases or on electrical fires.
How to use a fire extinguisher should be part of fire safety training. An easy way to remember how to operate an extinguisher is the acronym P.A.S.S which stands for pull, aim, squeeze and sweep.
1. Pull: Pull the pin to break the seal and activate the extinguisher.
2. Aim: Aim low and point the hose at the base of the fire. Do not hold the horn on a CO2 extinguisher as it could damage your skin.
3. Squeeze: Squeeze the handle to release the extinguishing agent.
4. Sweep: Sweep the hose back and forth at the base of the fire until it is out.
Our handy infographic includes important information on fires in the workplace. Feel free to download and share it!