These extinguishers contain CO2 at high pressure and are suitable for Class B fires. They won’t damage computers or other electrical equipment and are often sited alongside a water or foam extinguisher to cover the widest range of fire types. If you ever need to put out an electrical fire, remember to turn off the power supply to the equipment to ensure the equipment doesn’t re-ignite. You must also remember to avoid holding the horn as you deploy the extinguisher since it gets cold enough to freeze to your skin as the pressurised CO2 gas is forced out. CO2 extinguishers are not suitable for deep fat fryers since the force of the escaping gas can carry burning fat across the room.