GB/T 30646-2014 "Determination of Phthalate Content in Coatings by Gas Chromatography/Mass Spectrometry" specifies the method for determining the content of phthalates in coatings and raw materials used in coatings using gas chromatography/mass spectrometry (GC/MS). It is applicable to the detection of various phthalates such as DBP, BBP, and DEHP. The principle involves extracting target substances from the sample using methyl ethyl ketone solvent through ultrasonic extraction. After processing the extract, qualitative analysis is performed using the total ion chromatogram and mass spectrum in full-scan mode with a gas chromatograph/mass spectrometer, while quantitative analysis is carried out using selected ion monitoring combined with an external standard method. Auxiliary instruments such as an ultrasonic generator, centrifuge, balance, and organic phase microporous filter membrane are also required during the detection process. It is essential to avoid contamination from plastic utensils during analysis to ensure the accuracy of the detection.