What Does Class C Fire Mean?
A class C fire refers to a fire that involves flammable gases such as natural gas, petroleum gas, butane, hydrogen, acetylene or propane. These gases are highly combustible and may cause large scale fires and explosions if mixed with enough oxygen.
Safeopedia Explains Class C Fire
A class C fire does not leave embers or ashes and can be best extinguished by dry chemical powder and CO2. Before trying to extinguish a class C fire, the source of the gaseous substance must be found and cut off. This could be closing the valve of the gas containing cylinder. A spark in the presence of any of these gasses, with the required amount of oxygen, may also cause an explosion.