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Of all these subway accidents, fire accident may bring the most serious damage.Subway is a closed space, and it is linked to the outside world only by station entrances, ventilation booths and the entrance of the tunnel. In case of fire, due to inadequate ventilation, inadequate combustion, CO, CO2 and other toxic gas concentrations increased rapidly. Moreover, due to poor conditions of exhausting, a larger amount of smoke, heat gathere quickly, so the internal temperature will rise fast. Smoke spread through the same direction as the way people dispose, thus, subway accident will inevitably cause severe killing and injuring. Consequently, to understand the subway fire characteristics prior to the fire, and master its development will provide an important basis for the design of metro fire system.

BE endanger with a fire trouble in the subway trouble biggest.The subway conduct and actions is an underground space of sealing off, it and the external world mutually has the statio