GB/T 267-1988 prescribes the open cup method for the determination of flash point and ignition point of petroleum products. Applicable to a variety of petroleum products, the principle is to heat the sample in the open cup, and determine the flash point and ignition point by observing the flame condition. The standard specifies the required instruments, such as open cups, heating devices, etc., and specifies the preparation of experiments, including sample selection and instrument calibrating. Describe the heating operation process in detail, such as heating rate control, and the flash point and ignition point determination method. With this standard, the flash point and ignition point of petroleum products can be accurately determined, providing key data for the safety assessment of oil storage, transportation and use.