GB/T 24328.1-2009 is the first part of the series of standards for toilet paper and its products. As the basic standard, it clarifies the general principles and terminology of the series of standards. It defines the relevant professional terms and definitions of toilet paper and its products, the scope of application of normative standards, basic principles, and establishes the product classification framework. It provides a unified conceptual basis and guidelines for the formulation and implementation of subsequent part standards to ensure the standardization and conformity of the entire series of standards.