CO2 or Dry Chemical – Carbon Dioxide Extinguishers
This type of extinguisher is filled with Carbon Dioxide (CO2), a non-flammable gas under extreme pressure. These extinguishers put out fires by displacing oxygen, or taking away the oxygen element of the fire triangle. Because of its high pressure, when you use this extinguisher pieces of dry ice shoot from the horn, which also has a cooling effect on the fire.
You can recognize this type of extinguisher by its hard horn and absent pressure gauge.
CO2 cylinders are red and range in size from five to 100 pounds or larger.
CO2 extinguishers are designed for Class B and C (flammable liquid and electrical) fires only.
Important:
CO2 is not recommended for Class A fires because they may continue to smolder and re-ignite after the CO2 dissipates.
Never use CO2 extinguishers in a confined space while people are present without proper respiratory protection.
Locations:
Carbon dioxide extinguishers will frequently be found in industrial vehicles, mechanical rooms, offices, computer labs, and flammable liquid storage areas.
