põlemetemperatuur

Põlemetemperatuur, often translated as flash point, is the lowest temperature at which a volatile material can vaporize to form an ignitable mixture in air. At this temperature, sufficient vapor is produced to ignite when an open flame is introduced. This does not mean the liquid itself will continue to burn. Sustained combustion requires a higher temperature, known as the fire point.

The flash point is a critical safety parameter for flammable and combustible liquids. It is used to classify liquids and to inform handling, storage, and transportation regulations. For example, liquids with lower flash points are considered more hazardous as they can more easily form ignitable vapors at ambient temperatures.

Different methods exist for determining the flash point, most commonly using either open-cup or closed-cup testers. The closed-cup method generally yields a lower flash point than the open-cup method because it prevents vapor from escaping the test vessel, leading to a higher vapor concentration.

The presence of impurities can significantly affect the flash point of a substance. For instance, adding a small amount of a more volatile component to a liquid can drastically lower its flash point. Understanding the flash point is essential for risk assessment in various industries, including petrochemicals, manufacturing, and laboratories.