GB/T 37040-2018 "Limit and Determination of Carcinogenic Dyes in Dye Products" applies to dye products, specifying the limit requirements and determination methods for carcinogenic dyes. After pretreatment steps such as extraction and reductive decomposition, the samples are tested using gas chromatography-mass spectrometry or high-performance liquid chromatography. The standard defines specific limit indicators for carcinogenic dyes, determines their content through qualitative and quantitative analysis, and specifies permissible deviations for parallel measurement results, providing a scientific basis for the control of carcinogenic and hazardous substances in dye products.