GB5135.2-2025
Automatic sprinkler system—Part 2: Wet system alarm valves, retard chamber and water motor alarm
自动喷水灭火系统 第2部分：湿式报警阀、延迟器、水力警铃
GB 5135.2-2025 is an upcoming mandatory Chinese national standard for Automatic sprinkler system—Part 2: Wet system alarm valves, retard chamber and water motor alarm. It appears in the Environment compliance cluster with a product safety focus and has an implementation date of Nov 1, 2026.
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 applies to the design, manufacture, and inspection of wet system alarm valves, retard chambers, and water motor alarms used in automatic sprinkler systems. It is mandatory for manufacturers producing these specific fire protection components for the Chinese market. The standard replaces the previous GB 5135.2-2003 edition.
Technical requirements
The standard specifies comprehensive requirements for wet system alarm valves and associated components. Key areas include rated working pressure, which is set at either 1.2 MPa or 1.6 MPa. Material requirements mandate that valve bodies and covers use materials with corrosion resistance not lower than ductile iron, while seats must be bronze or better. Structural requirements dictate that no valves shall be installed between the alarm port and retard chamber, and pressure display devices for both supply and system pressure must be present. For valve flap type wet alarm valves, specific clearance dimensions between the flap and body must be maintained to prevent debris jamming. Performance criteria include strict limits on hydraulic friction (not exceeding 0.02 MPa at a flow velocity of 4.5 m/s) and alarm delay times. Valves must trigger continuous alarms within 15 seconds without a retarder, or between 5 to 90 seconds with a retarder installed. Additionally, components must withstand rigorous strength tests at 4 times the rated working pressure and fire resistance tests at 800°C for 15 minutes.
Testing methods
The standard outlines various testing procedures to verify compliance, including visual inspections, aging tests (air and warm water) for non-metallic parts, and strength tests. Manufacturers must conduct function tests under specific supply pressures and flow rates to ensure proper alarm signaling. Other key evaluations include hydraulic friction tests, pressure ratio tests, water shock resistance tests, and loudness tests for water motor alarms. Fire resistance is verified by exposing the water-filled valve to an 800°C flame for 15 minutes.
FAQs
What products are regulated under GB 5135.2-2025?
GB 5135.2-2025 regulates wet system alarm valves, retard chambers, and water motor alarms used in automatic sprinkler systems.
What are the rated working pressures specified in GB 5135.2-2025?
The standard specifies that the rated working pressure for these components must be either 1.2 MPa or 1.6 MPa.
Are there any updates from the previous version of GB 5135.2?
Yes, GB 5135.2-2025 replaces the 2003 version. Major changes include updated material requirements (upgrading to ductile iron), the addition of classification and model designation rules, and the removal of the 300mm nominal diameter specification.
The summary above provides a high-level overview of GB 5135.2-2025. 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 5135.2-2025 today to access all detailed parameters, tables, and testing procedures.
Applicability hints
- Type
- Product
- CCS
- C84
- ICS
- 13.220.10
- Competent department
- National Fire and Rescue Administration
- Technical committee
- National Technical Committee on Fire Protection of Standardization Administration of China
Relationships
Replaces:GB 5135.2-2003 (Current)