A fire extinguisher is designed to tackle and extinguish, or control and maintain small fires.

When it comes to choosing the right fire extinguisher it is important to know the type of fire you will be dealing with and which fire extinguisher is right for the job.

Choosing the wrong type of fire extinguisher can be very dangerous, make the fire worse and risk injuring those attempting to fight the fire.


Types of Fire Classes

Fires are caused by numerous reasons and it is vital to identify this cause.

Fires are identified using a classification system.

Each class identifies the type of fuel involved in the fire. This is the vital step to help decide which fire extinguisher needs to be used to tackle it.

The symbols below will be clearly marked on the label of each relevant fire extinguisher to give further guidance on selecting the correct one to use.


Class A

Class B

Class C

Combustable Solid Materials Flammable Liquids Flammable Gasses
Wood, Paper, Straw, Textiles, Coal etc. Petrol, Diesel, Oils, Paint Paraffin etc. Methane, Propane, Natural Gas etc.


Class D

Class F


Flammable Metals Cooking Oils and Fats Electrical Appliances
Magnesium, Aluminium, Lithium etc. Cooking Oil, Fats, Grease etc. Computers, Stereos, Fuse boxes etc.


Types of Fire Extinguishers

Each type of fire extinguisher is effective against a different kind of fire.

Once the fire class is identified, based on what is fueling the fire, the right fire extinguisher to tackle it can be chosen.

Below is an overview of each type of fire extinguisher including what fire classes they tackle.

Water fire extinguishers are suitable for fighting Class A fires (combustible solid materials)

Remember water conducts electricity and SHOULD NOT be used on electrical equipment.

They all have a red label.

AFFF Foam fire extinguishers are highly effective on Class B fires (flammable liquids) such as petrol.

The foam works to cover and seal the surface of the flammable liquid. This stops the vapour from reaching the air, preventing re-ignition.

They also work well on Class A fires

They all have a cream label

Carbon Dioxide (co2) was originally designed for use of flammable liquids therefore is highly suited for Class B fires.

It is also extremely effective on electrical fires as co2 is not a conductor.

Carbon Dioxide smothers the fire cutting off the oxygen supply

Carbon Dioxide extinguishers leave behind no harmful residue.

They all have a black label


ABC Powder extinguisher is so named due to the fact it can be used on Class A, Class B and Class C fires, as well as electrical.

It is available in a range of sizes and ideal for environments containing mixed fire risks.

It is not recommended for use within small rooms due to the risk of inhalation and loss of vision.

Note. There is a special dry powder extinguisher which is used specifically for Class D Fires.

Wet Chemical fire extinguishers are the most effective against Class F fires (cooking oils and fats) e.g fats, grease and oil.

Therefore they are practical in a kitchen environment.

The wet chemical rapidly extinguishes the flames, cools the burning oil and chemically reacts to form a soap-like solution, sealing the surface and preventing re-ignition.

They can also be used on Class A fires.

Water Mist fire extinguishers tackle Class A, Class B and Class C fires, rated risks as well as Class F and Electrical fires.

Water Mist is a new technology that works on the basis of cooling fire, suffocating it and then cooling the burning media to prevent re-ignition using microscopic particles of water.

Water mists extinguishers are ideal for covering areas of a building where multiple fire risks can be found.


Using a fire extinguisher

Fire extinguishers should not be used by people who have not been through a fire extinguisher course.

Before tackling a fire with a fire extinguisher make sure you or someone else has sounded the fire alarm and that you have a safe evacuation route.

Using the correct type of extinguisher for the fire, use the four-step PASS technique:

  1. Pull: Pull the pin, this will break the tamper seal.
  2. Aim: Aim low, pointing the nozzle or hose at the base of the fire. Do not touch the horn on a CO2 extinguisher, it gets very cold and can damage the skin.
  3. Squeeze: Squeeze the handle to release the extinguishing agent.
  4. Sweep: Sweep from side to side at the base of the fire, the fuel source, until the fire is out.

If there is the slightest doubt or uncertainty about tackling the fire evacuate the building immediately.


Fire Safety Training

Our fire safety courses are designed to give staff members the knowledge and skills required to implement systems that help prevent a fire from starting in their workplace and ensure safe evacuation if one does occur.

Accidental fire in the workplace can be devastating to a business resulting in damage to property, business continuity and in the worst cases loss of life and serious injuries to staff and customers.

All of our fire safety courses are delivered by fire safety professionals, in partnership with Act Fire Consultancy.

Contact us here or call 0141 280 3340 to hear more about our fire safety training.