This standard specifies a gas chromatograph detection method for the content of 4-tert-amyl phenol and p-teroctyl phenol in solar-based paints and water-based paints. The method is applicable to the determination of 4-tert-amyl phenol and p-teroctyl phenol in these coatings. In the principle section, Coating samples are extracted by ultrasound with methanol, and the extract solution is determined by Gas chromatography, CG, and quantified by external standard method. Reagents and materials include standard substances such as methanol, 4-tert-amyl phenol, and p-teroctyl phenol, as well as mixed standard stock solutions and mixed standard working solutions. Required instruments and equipment include Gas Chromatograph, Analytical Balance, ultrasonic cleaner, etc.