GB/T 5208-2008 "Determination of flash point—Rapid equilibrium closed cup method" specifies the method for determining flash point using the rapid equilibrium closed cup method, which is applicable to products such as paints, solvents, and petroleum. The method employs an electronically temperature-controlled closed cup flash point tester, where the sample is heated and automatically ignited to detect the minimum temperature at which flammable vapors flash upon exposure to a flame. The test requires equipment such as a rapid equilibrium closed cup flash point tester and an electronic ignition device, providing critical data for safety assessments in product storage, transportation, and use.