Flash point

The fire point is the lowest temperature at which the vapors keep burning after the ignition source is removed.

The flash point is the lowest temperature at which there will be enough flammable vapor to support combustion when an ignition source is applied.

The TAG flash point tester adheres to ASTM D56 and has no stirrer, while the Abel flash point testers adheres to IP 170 and ISO 13736 and has a stirring motor so the sample is stirred during testing.

For example, testing by the Pensky-Martens closed cup method is detailed in ASTM D93, IP34, ISO 2719, DIN 51758, JIS K2265 and AFNOR M07-019.

Determination of flash point by the Small Scale closed cup method is detailed in ASTM D3828 and D3278, EN ISO 3679 and 3680, and IP 523 and 524.

The fuel is mixed with air within its flammable limits and heated by compression and subject to Boyle's law above its flash point, then ignited by the spark plug.

Air is compressed until it heats above the autoignition temperature of the fuel, which is then injected as a high-pressure spray, keeping the fuel-air mix within flammable limits.

Flash points of substances are measured according to standard test methods described and defined in a 1938 publication by T.L.

Standard test methods are written and controlled by a number of national and international committees and organizations.