The spray function of the fog cannon can, to a certain extent, serve as an auxiliary means for fire fighting and extinguishing. In the early stage of a fire or for some minor fires, the fog cannon can spray a large amount of water mist to lower the temperature at the fire scene, suppress the spread of the fire, and buy time for firefighters to put out the fire. Meanwhile, for some high-altitude or hard-to-reach fire areas, the fog cannon can take advantage of its range to spray water mist to the corresponding positions for fire extinguishing or cooling.