GB/T 20313-2006 Specifies the drying method for the determination of moisture content of building materials and products. It specifies the requirements for drying equipment, such as thermostatic ovens, and details the steps of preparing and weighing the initial mass of the specimen. The specimen is placed in the oven, dried at a specified high temperature to a constant weight, and weighed again. The moisture content is calculated by the mass difference between the front and rear. This standard provides a unified method for accurately determining the moisture content of building materials and products. It helps to evaluate the performance of materials in different Humidity environments. It provides data support for the rational selection of materials and moisture-proof measures in building design and construction, and ensures the stability of building structures and the mass of indoor environments.