Effects of Wind Speed and Longitudinal Direction on Fire Patterns from a Vehicle Fire in a Compact Car

This paper compares the material consumption and fire patterns which developed on four nearly identical compact sedans when each was burned for exactly the same amount of time, but with different wind speed and direction during the burns. This paper will also compare the effects of environmental exposure to the fire patterns on the vehicles. The burn demonstrations were completed at an outdoor facility in southeast Michigan on four late model compact sedans. The wind direction was controlled by placing the subject vehicle with either the front facing into the wind, or rear facing into the wind. Two of the burns were conducted when the average observed wind speed was 5-6kph and two of the burns were conducted at an average observed wind speed of 19kph. The origin of the fire in each vehicle was the same, with the fire being set by a small incendiary device and allowed to burn freely for twenty-four minutes, then extinguished using water applied using techniques typical of municipal fire departments. The vehicles were then photographed to document the general fire patterns and material consumption immediately post-burn. The vehicles were moved to an outdoor storage lot, covered and exposed to the environment of a northern climate for a period of at least one year in order to simulate typical salvage yard conditions. The vehicles were then photographed again to document the general fire patterns post-storage. In addition observations regarding the melting of aluminum components, hood patterns, 12-volt battery plate separation and soot on interior glass surfaces were documented.