GB/T 9900-2025 is a special project standard for rubber or plastic coated fabric products, specially formulated for air ducts. The standard specifies the technical requirements of air ducts, including substrate performance, coating mass, structural strength, ventilating efficiency and weathering resistance, etc. At the same time, it stipulates inspection methods, inspection rules and signs, Encasement, transportation and storage requirements, suitable for the production, inspection and application of air ducts, can unify product mass standards, ensure its safe and reliable use in ventilated scenes such as mines and buildings, and provide key technical basis.