When we can use co2 fire extinguisher ?

• for all portable kind of fire extinguisher, used it whenever the flame is still small or still in the incipient phase. if the fire in the growth phase, not fully developed
• CO2 fire extinguisher is effective  to reduce amount of the oxygen. It can be used for fire type B (flammable liquids) and for fire type C (electrical)

Mostly used in electrical fire , CO2 system would be applicable in electrical rooms specially that rooms out side of the building itself (Co2 is a toxic gas at high concentration)