flampunkt

Flammpunkt, sometimes encountered in English-language texts as flash point or, less correctly, as flampunkt, is a property of liquids that indicates the lowest temperature at which the liquid’s vapors can form an ignitable mixture with air when an ignition source is present. It is a key parameter in safety, storage, and transportation of liquids.

The flash point is determined by measuring the temperature at which an ignition source causes the vapor above a liquid to ignite. Two common testing approaches are open-cup and closed-cup methods. Open-cup tests expose the liquid to the atmosphere, while closed-cup tests trap the vapors, typically yielding different results. The test method chosen affects the reported flash point and is specified by standards used in laboratories and industry.

In practice, the flash point is used to classify liquids for safety and regulatory purposes, distinguishing flammable liquids from combustible ones and informing handling, storage, labeling, and transport requirements. Regulations and guidelines often rely on flash point values to define hazard categories and to determine appropriate containment and ventilation measures.

Several factors influence measured flash points, including the liquid’s composition and impurities, presence of water, vapor pressure, container design, sample volume, surface area, and ambient conditions such as temperature and air flow. Because different tests yield different results, reported flash points should specify the method used (for example, the specific open- or closed-cup test standard).

Understanding the flash point helps assess fire risk and establish safe operating procedures for chemical work, chemical manufacturing, and the distribution of liquids.