Common sense of fire fighting: how to use dry powder fire extinguisher

Scope of application: sodium bicarbonate dry powder fire extinguisher is suitable for flammable, combustible liquid, gas and the initial fire of live equipment; Ammonium phosphate dry powder fire extinguisher can be used in addition to the above types of fires, but also can fight the initial fire of solid substances. But none of them can extinguish metal burning fires.

When the dry powder fire extinguisher extinguishers extinguish flammable and flammable liquid fires, they should strafe the quasi-flame points, and if the liquid fire being extinguished is flowing and burning, the root of the quasi-flame should be fired from near to far, and strafed left and right until all the flames are extinguished. If the combustible liquid burns in the container, the user should shake and strafe the root of the flame left and right, so that the dry powder stream ejected covers the entire open surface of the container; When the flame is driven out of the container, the user should continue to spray until the flame is completely extinguished. When fighting a fire of combustible liquid in the container, it should be noted that the nozzle cannot be directly aimed at the liquid level to spray, so as to prevent the impact force of the jet from splashing out the combustible liquid and expanding the fire, causing difficulty in fire extinguishing. If the combustible liquid burns in the metal container for too long, the wall temperature of the container is higher than the spontaneous ignition point of the combustible liquid, then it is easy to cause the phenomenon of re-ignition after fire extinguishing, and if it is combined with a foam fire extinguisher, the fire extinguishing effect is better.

How to use: When extinguishing the fire, you can quickly rush to the fire scene with a fire extinguisher in your hand or on your shoulder, and put down the fire extinguisher at about 5 meters away from the burning place. If you are outdoors, you should choose to spray in the upwind direction. If the dry powder fire extinguisher used is an external pressure storage type, the operator should hold the spray gun in one hand and lift the opening ring on the gas cylinder with the other hand. If the cylinder is opened on a handwheel, unscrew it counterclockwise and screw to the highest position, then lift the fire extinguisher. When the dry powder is ejected, it is quickly aimed at the root of the flame. If the dry powder fire extinguisher used is a built-in gas cylinder or a pressure storage type, the operator should first unplug the safety pin on the opening handle, then hold the nozzle part at the front end of the spray hose, and press the opening pressure handle down with the other hand to open the fire extinguisher to extinguish the fire. When using a fire extinguisher or a pressure storage fire extinguisher with a spray hose, one hand should always press down the pressure handle, and cannot be released, otherwise the spray will be interrupted.

Precautions for use: When using ammonium phosphate dry powder fire extinguishers to extinguish solid combustible fires, spray at the most violent place of ignition, and strafe up and down, left and right. If conditions permit, the user can carry the fire extinguisher along the perimeter of the burning material and spray it, so that the dry powder fire extinguishing agent is evenly sprayed on the surface of the burning material until the flame is completely extinguished.

The cart-type dry chemical fire extinguisher is used in the same way as the portable dry chemical fire extinguisher.