GB/T 1 2010.4 - 2010 provides specifications for the determination of pH value of plastic polyvinyl alcohol materials (PVAL). The standard details the treatment method of PVAL samples and prepares the solution for determination. Professional instruments such as acidity meters are used to strictly follow the operation procedures to accurately measure the pH value of the solution, covering key links such as instrument calibrate and measurement environment requirements. The recording and processing methods of measurement results are also clarified to ensure accurate and reliable measurement data. This standard provides an important basis for evaluating PVAL material mass and is widely used in plastics production, mass testing and other related industries to help control product quality.