When putting out fire, you can quickly rush to the fire site with a fire extinguisher by hand or shoulder, and put down the fire extinguisher about 5 meters away from the burning place. If it is outdoors, it shall be sprayed in the upwind direction. If the dry powder fire extinguisher used is external type and pressure storage type, the operator shall hold the spray gun tightly with one hand and lift the opening bail on the gas cylinder with the other hand. If the opening of the gas cylinder is handwheel type, unscrew it counterclockwise and turn it to the highest position, and 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 storage bottle or pressure storage type, the operator should first pull out the safety pin on the opening handle, then hold the nozzle at the front end of the spray hose, and press the opening handle with the other hand to open the fire extinguisher for fire extinguishing. When the fire extinguisher or pressure storage fire extinguisher with spray hose is in use, one hand should always press down the handle and cannot release it, otherwise the spraying will be interrupted.