arbon dioxide (CO2) extinguishers, also known as carbon dioxide fire extinguishers, are used to put out flammable liquid and electrical fires. They are often found in kitchens, restaurants, pubs, laboratories, mechanical rooms, and flammable liquid storage areas. CO2 extinguishers are non-toxic, non-conductive, and leave no residue. They are safe to use around food, machinery, and computer equipment.