What is the lowest temperature at which the vapors of a flammable liquid will ignite called?

The lowest temperature at which the vapors of a flammable liquid will ignite is referred to as the flash point. This is a critical safety parameter in handling flammable materials, as it determines the conditions under which a liquid can produce enough vapor to create a flammable mixture in the air. The flash point is significant for storage and transportation, as it helps in assessing the risks associated with a substance.

In contrast, the fire point is the temperature at which enough vapors are produced to not only ignite but continue to burn. It is always higher than the flash point. The autoignition temperature is the temperature at which a material will spontaneously ignite without an external spark or flame, which is also higher than the flash point. Vaporization temperature refers to the point at which a liquid turns to vapor but is not directly related to the flammability aspect. Understanding these definitions helps in recognizing the critical nature of the flash point in fire safety protocols.