Auto-Ignition Temperature
Definition
The minimum temperature at which a material ignites spontaneously without a pilot flame or spark. Relevant to the assessment of ignition scenarios in electrical and hot-surface fire causation.
- Definition
- Minimum temperature for spontaneous ignition
- No ignition source needed
- Unlike flash point
- Relevant to
- Electrical and hot-surface fire causation
Common questions
How does auto-ignition temperature differ from flash point?+
Flash point is the lowest temperature at which vapors will ignite when exposed to an external spark or flame. Auto-ignition temperature is higher and needs no external ignition source at all, the material ignites on its own.
Why does auto-ignition temperature matter when investigating an electrical fire?+
It helps assess whether a hot surface alone, such as an overloaded conductor or a failed component, could plausibly have ignited nearby combustible material without any separate spark or open flame.
Related terms
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- Convective Heat Transfer
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- Fire Tetrahedron
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- Flaming Combustion
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- Flash Point
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- Radiative Heat Transfer
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