This standard describes a method for determining the flash point of liquids using the cup-closure equilibrate method. This method ensures that the sample and the air/vapor mixture above it reach the temperature equilibrate by slow heating. The method is suitable for the Temperature range from 0 to 110 ° C, and is particularly suitable for low thermal conductivity and high viscosity liquids. This method provides a more uniform heating rate than the Miscellaneous test method, and is suitable for evaluating the flash point of liquids such as paints and Resin. When using, pay attention to the safety of mercury-containing products.