One of the more important data points to be collected in fire testing analysis is the auto-ignition temperature (AIT). The auto-ignition temperature of a substance is the lowest temperature at which it will spontaneously ignite in a normal atmosphere without an external source of ignition, such as a flame or spark. This temperature is required to supply the activation energy needed for combustion. Auto-ignition temperatures of liquid chemicals are typically measured using a 500 ml flask placed in a temperature controlled oven (in accordance with the procedure described in ASTM E659).
Knowing the AIT of a given substance can also help clarify behavior as a result of hot surface ignition in a non-standardized test configuration.
AIT and hot surface ignition testing is another valuable tool used by WHA's forensic engineers understanding the unique fire dynamics which occur in every fire.