GB/T 30696-2014 "Rigid Phenolic Foam Products—Determination of Free Phenol" applies to rigid phenolic foam products manufactured by acid-curing and alkali-curing methods, specifying the determination principle, instruments, and procedures for free phenol content. The detection requires the use of a gas chromatograph equipped with a hydrogen flame ionization detector (FID), an analytical balance with an accuracy of 0.1 mg, an ultrasonic extraction device, and standard test sieves of 0.425 mm and 0.106 mm. After grinding and sieving, the sample is subjected to ultrasonic extraction with acetone. The extract is filtered and injected into the chromatograph, and the internal standard method is used for quantification to ensure accurate detection results, providing a basis for product safety control.