Flash point is an important product quality specification for distillate fuels (such as diesel, home heating oil, and jet fuel). Flash point is the temperature at which a fuel emits enough vapor to form a combustible mixture of hydrocarbon and air.

Flash point specifications are a minimum temperature limit. A material with higher flash point is more desirable and safer to handle in storage systems.

Flash point is highly correlated with density. Generally, raising the flash point requires blending less light (low boiling point) material such as heavy naphtha and kerosene.