Extinguishers have a label on the front with operating instructions. The operating principle is the same for all extinguishers – PASS:

  1. Pull the pin. Extinguishers have a safety mechanism to prevent the extinguisher from being accidentally discharged. Usually the safety mechanism involves a pin held in place by a plastic tie. Since the plastic may stretch before breaking or may be difficult to break, twisting the pin first will break the tie easily.

  2. Aim at the base of the fire at the fuel. Aiming at the fire does no good, since the fire is only the products of combustion coming off the fuel.

  3. Squeeze the two parts of the handle to operate the valve and discharge the extinguishing agent.

  4. Sweep the extinguishing agent rapidly back and forth to cover all of the fuel and separate the fuel from the fire. In the case of flammable liquid fires, technique is very important. The bigger the fire, the more chance the fire will flash back because of the heated vapors.