The ignition temperature, also known as the autoignition temperature or self- ignition temperature, is the lowest temperature at which a substance spontaneously ignites in a normal atmosphere without any external ignition source such as a flame or spark. At this temperature, the substance provides enough energy for combustion to start on its own
. This temperature varies depending on the substance and is critical for safety and handling of flammable materials. For example, diesel has an ignition temperature around 210°C, gasoline around 247–280°C, and iron much higher at about 1315°C, indicating how easily these materials catch fire relative to each other
. The ignition temperature is distinct from the flash point, which is the lowest temperature at which a substance produces enough vapor to ignite in the presence of an external flame but does not necessarily sustain combustion. The autoignition temperature is generally higher than the flash point
. In summary, ignition temperature is the minimum temperature needed for a substance to ignite spontaneously without any spark or flame, making it a key parameter in fire safety and chemical processing
