ISO 6182-6:2020

Overview - ISO 6182-6:2020 (check valves for automatic sprinkler systems)

ISO 6182-6:2020 is the international standard that specifies performance, requirements, test methods and marking for check valves used to supply water in automatic fire protection sprinkler systems. It applies to check valves (not trim valves) installed in the main waterway of sprinkler installations to prevent backflow and to help manage multiple pumps or flow-switch arrangements. Key takeaways: minimum nominal size DN25, rated working pressure ≥ 1.2 MPa (12 bar), and comprehensive mechanical, hydraulic and ageing tests.

Key topics and technical requirements

• Scope and applicability
  • Check valves for automatic sprinkler systems; not applicable to trim valves.
• Nominal sizes & connections
  • Valve sizes ≥ DN25; connections must meet the rated working pressure and relevant international/national standards.
• Rated working pressure
  • Minimum specified: 1.2 MPa (12 bar); manufacturer must specify rated working pressure.
• Materials and construction
  • Bodies and covers: materials with corrosion resistance at least equivalent to cast iron.
  • Cover fasteners: steel, stainless steel, titanium or equivalent.
  • Non-metallic body parts restricted; melting point of metals < 800 °C not permitted.
• Mechanical strength
  • Assembled valve (sealing assembly blocked open) must withstand 4× rated working pressure for 5 minutes without rupture.
• Hydraulics and clearances
  • Clearances, sealing assembly geometry and hydraulic friction loss are specified and tested.
• Operational durability and ageing
  • Endurance tests, spring tests, warm-water and air ageing for non-metallic components; salt mist corrosion assessment.
• Leakage and sealing
  • Defined leakage limits and deformation tests; sealing assembly must resist wear and allow maintenance.
• Testing, production control and marking
  • Production testing, sample tests (spring, body strength, leakage, endurance, friction loss) and marking/installation instructions required.

Practical applications - who uses this standard

• Manufacturers of check valves for sprinkler systems - for design, material selection, testing and marking.
• Test laboratories and quality-control teams - to perform required hydraulic, mechanical and ageing tests.
• Fire protection engineers and system designers - to specify compliant check valves and confirm rated working pressures, friction loss and maintenance access.
• Installers and maintenance personnel - for correct installation, serviceability and interpretation of manufacturer instructions.
• Authorities having jurisdiction and procurement teams - to assess product conformity for building fire-safety systems.

Related standards

• ISO 6182 series (other parts for automatic sprinkler systems)
• Normative references cited in ISO 6182-6: ISO 898-1 and ISO 898-2 (mechanical properties of fasteners)

This standard is essential when selecting, testing or certifying check valves for automatic sprinkler systems, ensuring reliable backflow prevention, hydraulic performance and long-term durability in fire protection applications.