ISO 22760-6:2024

Overview

ISO 22760-6:2024 specifies requirements for pressure relief valves (PRVs) used to limit internal pressure of dimethyl ether (DME) fuel containers on road vehicles (types defined in ISO 3833). It sets definitions, general design principles, marking and instruction requirements, and a suite of mandatory tests to verify safety and performance for DME fuel systems. The standard applies to vehicles using gaseous fuels in accordance with ISO 16861 and is part of the ISO 22760 series for DME fuel system components.

Key topics and technical requirements

• Scope and applicability
  • Covers PRVs for vehicle fuel containers using DME; excludes stationary, ship, rail, aircraft installations, electronic fuel management, refuelling receptacles and unrelated vehicle fuel parts.
• Marking and traceability
  • Components must be marked with manufacturer/agent, model/part number, working pressure (and temperature range), and discharge pressure. Additional recommended markings include flow direction, fuel type (DME), serial/date code and reference to ISO 22760-6.
• Design principles
  • PRV inlet positioning should avoid contact with the liquid phase of the fuel when possible.
  • Discharge pressure must not exceed the container working pressure.
• Essential tests (selected)
  • Hydrostatic strength: test at 2.25 × working pressure to verify housing integrity.
  • Leakage: internal and external leakage tests at specified temperatures and pressure factors (e.g., −40/−20 °C, 20 °C, 85 °C with factors such as 0.75×WP, 0.025×WP, 0.05×WP).
  • Continued operation: cyclic venting test - pressurize to discharge pressure, vent, re-seat within 10 s ± 2 s; 600 continuous cycles required.
  • Operational test: measure discharge and re-seating pressures at −40 °C, 20 °C and +85 °C. Initial pressurization to 110% of working pressure; acceptance criteria include ±5% tolerance on advertised discharge pressure and minimum re-seating ratios (e.g., re-seating ≥ 90% of discharge at 20 °C).
• Production quality
  • Manufacturers must implement continuous production batch inspection and acceptance testing to maintain consistent safety performance.

Applications and users

ISO 22760-6 is used by:

• PRV and DME fuel component manufacturers for product design, verification and marking.
• Automotive OEMs and fuel system integrators specifying compliant DME fuel systems.
• Test laboratories and certification bodies conducting hydrostatic, leakage and functional PRV testing.
• Regulators, conformity assessors and procurement teams requiring documented safety and traceability for DME vehicle systems.

Related standards

• ISO 22760-1 (general requirements and definitions)
• ISO 22760-2 (performance and test methods)
• ISO 16861 (DME fuel specifications)
• ISO 3833 (vehicle types)
• ISO 11114-2 and other referenced material-compatibility and environmental test standards

Keywords: ISO 22760-6, pressure relief valve, PRV, DME, dimethyl ether, fuel system components, hydrostatic strength, leakage test, operational test, vehicle fuel safety.