CO2 fire extinguishers (carbon dioxide) are the only fire extinguisher recommended for fires involving electrical equipment. CO2 is safe to use on and around electrical equipment, as the gas itself is non-conductive, and once used, there is no sticky foam or messy powder left behind. They are also effective on Class B fires (flammable liquids).

Carbon dioxide fire extinguishers are painted bright red with a black panel above the operating instructions. They have a distinctive horn-shaped nozzle at the side on the smaller models with 5kgs and above having a hose and horn.

Extinguishers of 9kgs or higher are available but tend to come mounted onto a wheeled trolley as they will be far too heavy to be carried safely. It is possible to find 45kg twin cylinder wheeled units for offshore or airport use.