Autoignition temperature

Lowest temperature at which a substance spontaneously combusts

The autoignition temperature or self-ignition temperature, often called spontaneous ignition temperature or minimum ignition temperature and formerly also known as kindling point, of a substance is the lowest temperature at which it spontaneously ignites 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. The temperature at which a chemical ignites decreases as the pressure is increased.Substances which spontaneously ignite in a normal atmosphere at naturally ambient temperatures are termed pyrophoric.

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