Sanitary napkins and sanitary pads are important sanitary products for women, which require strong absorption capacity. In the current product standard "Sanitary Napkins (Including Sanitary Pads)", the water absorption rate is a quality index to measure the absorption capacity of sanitary napkins. The larger the water absorption rate, the stronger the product's absorption capacity. Therefore, the water absorption rate is also an important technical indicator for controlling the quality of sanitary napkins. The water-absorbing material of sanitary napkins generally adopts polymer water-absorbing resin (SAP for short). SAP is a typical functional polymer material. The amount of SAP added directly affects the water absorption rate of sanitary napkins. Testing the water absorption rate of sanitary napkins can not only monitor the absorbency of the product, but also realize the control of the amount of SAP added. In order to ensure product quality, during the production process, the water absorption rate is generally tested every 20 to 30 minutes. Today we will elaborate on the specific test methods according to the requirements of the national standard "Sanitary Napkins (Including Sanitary Pads)".