CO2 Fire Extinguishers
Fires don’t all behave the same, which is why fire extinguishers aren’t one-type-fits-all. CO2 fire extinguishers aren’t the most versatile, but they’re crucial in the right environments. You won’t use them for general fires, but when electrical equipment or flammable liquids are involved, they’re the best choice.
They’re commonly found in places like offices, server rooms and workshops where electrical risks are part of daily operations. Since they don’t leave behind foam or powder, they’re safe to use around sensitive equipment. If your building has cables, computers or fuels on site, a CO2 extinguisher is essential.
What is an CO2 Fire Extinguisher?
CO2 fire extinguishers, also known as carbon dioxide fire extinguishers, are made for dealing with fires involving electrical equipment or flammable liquids such as petrol. They do not spray water or foam. Instead, they release carbon dioxide gas that’s stored under high pressure.
When discharged, the gas quickly removes oxygen from the area around the fire. That’s what puts the flames out. It also cools the burning material, helping stop the fire from starting up again. It leaves no messy residue and causes no damage to electronics. You’ll recognise one by its black label and discharge horn.
These extinguishers aren’t for everything though. They’re not suited to fires involving paper, wood or fabrics. Also, they should never be used in tight spaces without proper ventilation, as the gas they release can affect breathing.
We can supply extinguishers to suit the needs of many different industries including
- Vehicles
- Commercial
- Residential
- Healthcare
How Does a CO2 Fire Extinguisher Work?
CO2 fire extinguishers put out flames by releasing carbon dioxide gas at high pressure. Once triggered, the gas surrounds the fire and pushes oxygen out of the area. Since fire needs oxygen to keep burning, removing it causes the flames to die down quickly.
The gas also has a cooling effect. It comes out cold enough to lower the temperature of the burning material, which helps stop the fire from starting back up once it’s been extinguished.
Unlike other extinguishers, CO2 does not leave any residue. There is no foam or powder involved, which means it will not damage electrical items. This makes it especially useful in offices, data centres and anywhere sensitive equipment is in use.
One key safety point to keep in mind: the discharge horn becomes extremely cold during use. Never hold it directly. Always grip the handle provided and make sure the area is well ventilated.
What Fires Are CO2 Fire Extinguishers Used For?
CO2 fire extinguishers are designed for specific types of fires where other extinguishers may not be safe or effective. One of their main uses is for electrical fires, including those involving computers, wiring, control panels or other electrical equipment. Because they don’t leave any residue behind, they’re a safe choice around delicate systems.
They are also suitable for Class B fires, which involve flammable liquids such as petrol, oil, or solvents. These types of fires are common in garages, workshops and some industrial working environments.
However, CO2 extinguishers are not suitable for Class A fires, which include materials like paper, wood, or textiles. They also shouldn’t be used on cooking oil fires or in confined spaces with poor airflow. In those cases, other options like foam extinguishers or wet chemical extinguishers are more appropriate.
Pros and Cons of CO2 Fire Extinguishers
Pros:
- No residue = ideal for electronics – CO2 leaves no foam or powder behind, so it won’t damage electrical equipment.
- Compact and widely available – These extinguishers are easy to store and commonly used in offices and server rooms.
- No clean-up needed – Once used, there’s nothing to wipe up, making them practical in areas where cleanliness matters.
- Non-damaging to most surfaces – Because it’s a gas, CO2 will not stain or corrode the things it touches.
Cons:
- Can be dangerous in enclosed areas – CO2 can displace air, so it’s not safe in tight spaces without proper ventilation.
- Cold discharge may harm users – The horn gets extremely cold and can cause injury if touched during use.
- Ineffective on Class A or kitchen fires – These extinguishers won’t work on burning paper or cooking oil fires
Who Needs a CO2 Fire Extinguisher?
- Offices with electrical equipment – Ideal for workplaces with computers, printers or server setups that can’t be exposed to foam or powder.
- Schools, hospitals, and public buildings – These environments often include a mix of electrical systems and public footfall, making CO2 a safe and clean option.
- Workshops with flammable liquids – Where petrol, oils or solvents are used, CO2 extinguishers help manage Class B fire risks.
- Data centres, retail environments – In places with sensitive electronics or display systems, CO2 units prevent damage while offering fast response to electrical fires.
- Often part of a fire extinguisher mix – CO2 extinguishers, including the popular 5kg CO2 model, are regularly chosen for workplaces where a balance of coverage and compact size is needed.
How to Use a CO2 Fire Extinguisher?
Using a CO2 fire extinguisher starts with knowing the correct steps and staying aware of safety precautions. The PASS technique applies here, but there are a few key points specific to CO2.
Step-by-step:
- Pull the safety pin
This unlocks the handle, leaving the unit ready to use. - Aim at the base of the fire
Point the discharge horn low, toward the base where the flames begin. - Squeeze the lever
The carbon dioxide gas is released by squeezing the lever firmly. - Sweep side to side
Move the horn slowly from side to side to cover the fire area evenly.
Important safety tips:
Never hold the discharge horn directly, as it becomes extremely cold and can cause frostbite. Some models include a frost free horn, but always check before use and grip the handle only. Make sure the room has proper ventilation, especially if it’s a smaller space. Evacuate the area immediately and call emergency services if the fire spreads or becomes too difficult to control.
CO2 fire extinguishers play an essential role in protecting against electrical fires and those involving flammable liquids. They’re clean, effective, and safe to use around equipment where other extinguisher types might cause damage.
When used correctly, CO2 units offer fast, reliable control over specific fire risks without leaving a mess behind. They’re a smart choice for many workplaces, especially where electronics are in regular use.
Not sure if a CO2 extinguisher is right for your building? Contact B9 Fire & Security to speak with our team about fire safety options tailored to your environment.