Abstract: The investigation of a fire accident in an auto repair factory are carried out. By fire scene investigation, video surveillance analysis, the fire cause was decided to be the cable overload igniting the surrounding combustibles. At the same time, considering the fire risk of potential ignition sources in the spray painting room may ignite the flammable paint mist generated during painting operation, fire hazard parameters test, including the test of flash point, combustion point and lower explosion limit of liquid vapor were performed on some materials commonly used, such as thinner, varnish, metal topcoat, common topcoat, primer and curing agent. the general rules of fire in the auto repair factory and the spray painting room are summarized based on the investigation and tests. The study can provide a reference for the prevention, rescue and investigation of such accidents.

Key words: paint booth fire, ignition source, fire investigation