GB25502-2024
Minimum allowable values of water efficiency and water efficiency grades for water closets
坐便器水效限定值及水效等级
GB 25502-2024 is a current mandatory Chinese national standard for Minimum allowable values of water efficiency and water efficiency grades for water closets. It appears in the Food compliance cluster with a environmental protection focus and has an implementation date of May 1, 2025.
Applicability depends on product scope, certification route, competent authority notices and transition rules. Requst for the translation or verify source before using this record in a compliance decision.
Compliance overview
Scope and applicability
This standard is applicable to water closets installed on cold water pipelines in building facilities, which use water as the main flushing medium, have a water seal function, and do not have a warm water washing function. It is mandatory for all manufacturers producing water closets for the Chinese market. It does not apply to squatting pans or smart toilets with cleaning functions.
Technical requirements
The standard specifies the water efficiency grades for water closets, dividing them into 3 levels, with Grade 1 being the highest efficiency. It defines the minimum allowable values of water efficiency which serve as the mandatory threshold for market access. Manufacturers must ensure their products meet at least the Grade 3 limit for standard models and Grade 2 for toddler models. It details comprehensive flushing function requirements, including washability, water seal recovery, sewage replacement, and discharge functions (ball, granule, and mixed media). The standard also specifies requirements for water seal depth (minimum 50 mm), water seal surface dimensions, and the minimum passage diameter of the trap. For dual-flush water closets, specific testing parameters for both full and half flush cycles are defined. The standard also references performance requirements for non-matched flush valves when tested with standard water closets.
Testing methods
The standard outlines specific testing procedures under defined hydrostatic pressures (0.14 MPa, 0.24 MPa, and 0.55 MPa depending on the flushing mechanism). Key tests include the flushing water consumption test using a calibrated test rig, washability test using ink lines, and discharge function tests using standardized media like solid balls, HDPE granules, and sponge strips. It also details the drainage pipeline transport characteristics test to measure the average transport distance of solid balls.
FAQs
What products are regulated under GB 25502-2024?
GB 25502-2024 regulates water closets (toilets) installed on cold water pipelines in buildings that use water as the main flushing medium and have a water seal function, excluding those with warm water washing features.
Are there any updates from the previous version of GB 25502?
Yes, compared to GB 25502-2017, the 2024 version updates the scope, terminology, water efficiency grades, and technical requirements. It also adds new sections on test apparatus and acceptance procedures for discharge test media.
What is the minimum water efficiency grade required for market access?
Standard water closets must meet at least the Grade 3 water efficiency limit, while toddler water closets (seat height < 370 mm) must meet at least the Grade 2 limit.
The summary above provides a high-level overview of GB 25502-2024. To ensure complete compliance for your products entering the Chinese market, a precise and professional translation of the full technical specifications is essential. Purchase our high-quality English translation of GB 25502-2024 today to access all detailed parameters, tables, and testing procedures.
Applicability hints
- Type
- Management
- CCS
- Q31
- ICS
- 91.140.70
- Competent department
- Standardization Administration of China
- Technical committee
- National Technical Committee on Water Conservation of Standardization Administration of China
Relationships
Replaces:GB 25502-2017