GB/T 2408 - 2021 is used to determine the combustion performance of plastics, covering both horizontal and vertical methods. The standard describes the test principle and specifies the technical requirements of test equipment, such as combustion boxes and ignition devices. Detailed preparation of plastic samples, including size, quantity and pretreatment. Standardize the horizontal and vertical test processes respectively, such as ignition mode, flame action time, observation and recording of combustion length, combustion time, drop situation, etc. Through this standard, the combustion characteristics of plastics in different directions can be comprehensively evaluated, providing a unified and accurate detection basis for plastic production and Application, and improving the fire safety of plastic products.