Abstract: According to the disaster characteristics and main hazard characteristics of high-rise, underground, large-span and other confined space buildings after fire, combined with the actual needs, this paper uses the micro structure compressed air foam extinguishing system, and uses high-precision mixed compressed air foam system with particle size in the range of 100~200 μm to effectively suppress the fire in the confined space buildings, and investigates the actual impact of the gas-liquid ratio, gas-liquid mixing pressure, gas-liquid mixing speed and other related factors of the compressed air foam extinguishing system on the fire disposal process of confined space buildings. The results show that the compressed air foam has the corresponding advantages of sufficient foaming, uniform and delicate foam, good stability, high fire extinguishing efficiency, and strong anti reburning ability. When the gas-liquid ratio of the compressed air foam fire extinguishing system is 6:1, the gas-liquid mixing pressure is 0.9 MPa, and the gas-liquid mixing speed is 6 m3/s, the system achieves the best fire extinguishing efficiency, and has obvious effect on the practical disposal of building fires in confined space. The experimental results provide a basis for efficient fire scene disposal, combat organization, and other comprehensive fire extinguishing technical and tactical measures for frontline firefighting and rescue teams, which is conducive to promoting the effective improvement of the team's practical disposal efficiency.

Key words: compressed air foam, confined space buildings, fire extinguishing and disposal, drainage time