GB/T 19250-2013 "Polyurethane Waterproofing Coatings" specifies the classification, technical requirements, test methods, inspection rules, as well as the requirements for labeling, packaging, transportation, and storage of polyurethane waterproofing coatings used for building engineering waterproofing. The standard categorizes products into single-component and multi-component types based on their composition, and divides them into Type I, Type II, and Type III according to their basic performance. It also stipulates the requirements for exposed and non-exposed use, as well as limits on hazardous substances (Category A and Category B). This standard applies to polyurethane waterproofing coatings used for various types of engineering waterproofing.