On April 2, 2026, the Department of Science and Technology of China’s Ministry of Industry and Information Technology (MIIT) issued an announcement. Pursuant to the mandatory national standard development and revision plan issued by the Standardization Administration of China, the MIIT has organized the drafting of amendment drafts (soliciting comments) for two mandatory national standards, including the Safety Technical Specifications for Construction Waterproof Coatings, and has now published them for public comment.
Revision Background
Both amendments share the same rationale: the referenced mandatory national standard Classification for Burning Behavior of Building Materials and Products has been updated. GB 8624—2025 Classification for Burning Behavior of Building Materials and Products was officially released on December 31, 2025. It introduces new classification requirements for the burning behavior of roof covering materials and products, and also adjusts the test methods corresponding to Class B2. To ensure consistency among mandatory standards, it is necessary to update the burning behavior test methods for waterproof coatings and sheets accordingly, eliminating the previous practice of setting different test conditions based on roof slope, and directly applying the relevant provisions of the new GB 8624—2025.
Amendment No. 1 to GB 45671—2025 Safety Technical Specifications for Construction Waterproof Coatings
GB 45671—2025 Safety Technical Specifications for Construction Waterproof Coatings was released on April 25, 2025. Based on the content of GB 8624, Amendment No. 1 revises the requirements for the shape, dimensions, and number of coating film specimens for the burning behavior of flexible waterproof coatings, as well as the test method for burning behavior. It stipulates that the shape, dimensions, and number of specimens shall comply with GB 8624, and the test shall be conducted in accordance with GB 8624.
Amendment No. 1 to GB 45320—2025 Safety and General Technical Specifications for Construction Waterproof Sheets
GB 45320—2025 Safety and General Technical Specifications for Construction Waterproof Sheets was released on March 28, 2025. Based on the content of GB 8624, Amendment No. 1 removes the requirements for the shape, dimensions, and number of burning behavior test specimens, and revises the burning behavior test method, requiring that the test be carried out in accordance with GB 8624.
Implementation Date
The recommended implementation date for both amendments is January 1, 2027. The recommended supervisory authority for implementation is the State Administration for Market Regulation.
Comments Solicitation
Any interested parties who have different opinions are invited to fill out the Feedback Form for Mandatory National Standards and send it via email to kjbz@miit.gov.cn during the period from April 3, 2026, to June 1, 2026.



