A guide to Co2 Fire Extinguishers

CO2 fire extinguishers contain pure carbon dioxide and are used mainly on fires involving live electrical equipment or those involving flammable liquids. In this handy guide, we explain all about how this type of extinguisher works, when it should and shouldn't be used and which premises would benefit from one.

Which type of fire should a CO2 fire extinguisher be used on?

This type of fire extinguisher is the only one recommended for use on fires that have been started through faults in live electrical equipment. Carbon dioxide is safe to use on electrical equipment because the gas is non-conductive and the residue it leaves behind won't damage electrical equipment or machinery. CO2 extinguishers are also suitable for Class B fires (flammable liquids like petrol or oil) but they should never be used on cooking fires because its powerful discharge could easily splash burning fat and fan the fire. They're not deemed suitable for Class A fires (flammable solids), Class C fire (Flammable gases), Class F Fires (Cooking Oils).

How does a CO2 fire extinguisher work?

Carbon dioxide is stored in the canister in liquid form. Once released into the air, it suffocates the fire, starving it of oxygen. 

How is a CO2 fire extinguisher identified?

The canister has a red body and a black banner running along the top section, which labels it CO2. The smaller 2kg Co2 (Pictured left) has a swivel horn. The larger 5kg Co2 has a hose and horn. 

You can also purchase CO2 fire extinguishers in the following colours - Polished Silver, Antique Copper and Polished Gold


2kg Co2 Fire Extinguisher
2kg Co2 Fire Extinguisher
5kg Co2 Fire Extinguisher
5kg Co2 Fire Extinguisher


Where is a CO2 fire extinguisher most suitable for use?

This type of fire extinguisher is most suited to settings with electrical fire risk. Offices, Schools, Care homes and Hospitals would benefit from having them on site because of the volume of electrical equipment present in the building. Fire extinguishers should always be either fixed to the wall or placed an a fire extinguisher stand. They cannot be left floor standing as stated in the British Standards. 


2kg Co2 fire extinguisher paired with a 6ltr foam fire extinguisher. Mounted on a red double stand with ID signs.
2kg Co2 fire extinguisher paired with a 6ltr foam fire extinguisher. Mounted on a red double stand with ID signs.


How to use a CO2 fire extinguisher

2kg Co2 - Pick up the fire extinguisher and identify the safety pin located in the handle. Pull and twist the safety pin which will break the plastic seal. When the pin has been removed from the handle pull the swivel horn to the 9 o'clock position. Once in place the horn should not move. Take care not to hold the horn - it becomes very cold during use and could lead to severe frost burns. Aim the horn towards the base of the fire and sweep it from side to side until the fire is extinguished.

Always keep an eye on the area in case the fire re-ignites.

5kg Co2 - Pick up the fire extinguisher and identify the safety pin located in the handle. Pull and twist the safety pin which will break the plastic seal. When the pin has been removed from the handle hold the hose and horn assembly. You can hold the horn with 5kg Co2 fire extinguishers without getting a cold burn providing you use the handle section. Aim the horn towards the base of the fire and sweep it from side to side until the fire is extinguished.

Always keep an eye on the area in case the fire re-ignites.

Think this type of extinguisher is suitable for your premises? View our extensive range of CO2 extinguishers now. Alternatively, download our simple-view extinguisher guide.

This advice does not replace the need for fire extinguisher training. If you require fire training click here to make an enquiry or call us on 01582 533587