Vehicle Fluids


Almost every fluid onboard a motor vehicle is flammable
under certain conditions.


Temperature is sufficient to vaporize a fluid


There is a region in which the mixture with oxygen will support combustion


There is a sufficient ignition source present in the same region


Each of these fluids may ignite and propagate fire to adjacent materials.


When it is necessary to identify the originating fuel source, the investigator must examine each vehicle system to determine whether any fluid was involved in the cause of the fire.

Flammable and combustible fluids

During a fire investigation, it is often necessary to assess the possibility that one or more of these fluids was the originating fuel. To do so, it is important to understand the characteristics of each. (Battery acid is the one fluid that is not flammable.)