CO2 Fire Extinguishers
CO2 fire extinguishers put out flammable-liquid and electrical fires without leaving any residue behind. Carbon dioxide is stored as a liquid under high pressure and discharges as a cold gas cloud that displaces the oxygen around the fire. When the gas dissipates, there is no powder to clean up and nothing to damage sensitive equipment.
That clean discharge is why CO2 extinguishers are the standard choice near electrical panels, switchgear, server and telecom rooms, laboratories, machine shops and food processing areas. Every model carries a B:C rating, so it is listed for flammable liquids and gases (Class B) and for energized electrical equipment (Class C).
We stock CO2 fire extinguishers from Badger, Buckeye and Kidde in four sizes:
- 5 lb for small electrical rooms, labs and mechanical spaces
- 10 lb for server rooms, workshops and production lines
- 15 lb and 20 lb for larger electrical rooms and industrial hazards
Every model on this page is rechargeable and comes with a wall hook. CO2 cylinders are heavier than dry chemical units of the same agent weight, because the steel or aluminum shell must hold high pressure, so check the shipping weight when you plan placement.
Compare sizes and brands below, or read our CO2 fire extinguisher guide further down the page for where to use them and how to maintain them.
How a CO2 Fire Extinguisher Works
A CO2 fire extinguisher holds carbon dioxide as a liquid at roughly 850 psi. When you squeeze the handle, it flashes into a gas and snow mixture that leaves the horn at very low temperature. The gas pushes oxygen away from the fire and the cold discharge removes some heat. Because the agent is a gas, it reaches into equipment cabinets and around obstructions without leaving any residue.
Where to Use a CO2 Fire Extinguisher
Electrical and data equipment
Switchgear, transformers, control panels, servers and telecom racks can be ruined by dry chemical powder. A CO2 extinguisher protects them without cleanup or corrosion.
Labs, kitchen prep areas and food processing
Where powder contamination is a problem, CO2 handles small flammable-liquid fires cleanly. It is not a replacement for a Class K unit on deep fryers.
Machine shops and mechanical rooms
Cutting oils, solvents and motor fires are common Class B and C risks in shops and plant rooms.
CO2 Fire Extinguisher Limitations
CO2 extinguishers are not rated for Class A fires. The gas can blow burning paper and debris around, and a deep-seated fire can reignite once the gas disperses. Range is short, usually 3 to 8 feet, so the operator must get close. In small enclosed rooms, the discharge can lower oxygen to dangerous levels, so ventilate the space before re-entering. Never touch the horn during discharge, because it gets cold enough to cause frostbite.
If a space has both electrical equipment and ordinary combustibles, pair the CO2 unit with an ABC fire extinguisher or choose a clean agent extinguisher rated for Class A.
CO2 Fire Extinguishers vs. Clean Agent
Both protect electronics without residue. A CO2 fire extinguisher costs less and is cheap to recharge, but it has short range and no Class A rating. A clean agent unit costs more, reaches farther, and in larger sizes adds a Class A rating, which suits server rooms full of paper, cabling and electronics. Many facilities use CO2 in electrical rooms and clean agent units next to the server racks.
Choosing the Right Size CO2 Fire Extinguisher
The 5 lb CO2 fire extinguisher is the most compact and suits small electrical rooms. Most commercial buildings use 10 lb units. The 15 lb and 20 lb sizes discharge longer and reach a higher B rating, which is useful for large switchgear rooms and industrial hazards. Weigh the unit against the people who will carry it, since a 20 lb CO2 extinguisher weighs far more than 20 lb once you add the cylinder.
CO2 Fire Extinguisher Maintenance
CO2 extinguishers have no pressure gauge. Check them by weight: a unit that has lost more than 10 percent of its agent weight needs recharging. Steel and aluminum CO2 cylinders need a hydrostatic test every five years, along with the monthly visual inspection and annual maintenance OSHA requires for all workplace extinguishers. Keep the horn and hose free of cracks, and stock spare hooks and signage from our extinguisher accessories department.