ISO 22760-4:2024

Overview

ISO 22760-4:2024 specifies requirements for level indicators used in dimethyl ether (DME) fuel systems for road vehicles (as defined in ISO 3833). It defines terminology, marking, general design principles and mandatory tests to ensure safe, reliable measurement of DME fuel level in vehicle applications. The document applies to vehicles using gaseous fuels in accordance with ISO 16861 and excludes most fuel containers, non-road/ship/rail/aircraft installations, electronic fuel management and refuelling receptacles. (All pressures are gauge unless stated.)

Key topics and technical requirements

• Marking: Components must be traceable with manufacturer name/trademark, model/part number and working pressure (or pressure/temperature range). Recommended entries include flow direction, fuel type, electrical rating, certification symbol/approval number and serial/date code.
• Design & assembly: Level indicators must comply with ISO 22760-1 and ISO 22760-2. Electrical connections are to meet IP54 (IEC 60529). Accuracy must be sufficient to support the correct operation of the system 85% stop valve (see ISO 22760-3).
• Mandatory tests: A defined test suite (see Table 1) includes:
  • Hydrostatic strength: test at 2.25 × working pressure.
  • Leakage: tests at specified temperatures and pressure factors (e.g., −40/−20 °C, 20 °C, 85 °C with pressures scaled to working pressure).
  • Continued operation: system-level endurance including assembly testing, tank filling to 85% stop valve actuation, then cycling the indicator 4,000,000 times around the critical level (±10% at >2 Hz) and additional 6,000 full-range cycles; subsequent hydrostatic re-test required.
  • Insulation resistance: 1 000 V DC between connector pins and housing for ≥2 s; resistance > 240 kΩ.
  • Float pressure test: floats (if present) must withstand 4 500 kPa for 1 min with no visible deformation or cracking.
• Applicability notes: Some tests apply only to electrically connected indicators or those exposed to environmental conditions.

Applications and users

ISO 22760-4:2024 is intended for:

• OEMs and vehicle system integrators designing DME-powered road vehicles
• Component manufacturers and suppliers of DME level indicators / fuel level sensors
• Test laboratories and certification bodies performing compliance and type-approval testing
• Regulatory agencies and technical spec writers for gaseous-fuel vehicle safety

Benefits include consistent safety margins, traceability, interoperability within the ISO 22760 series, and clear test protocols that reduce risk of overfilling and system failure.

Related standards

• ISO 22760-1 (general requirements)
• ISO 22760-2 (performance and test methods)
• ISO 22760-3 (85% stop valve)
• ISO 22760-6, ISO 22760-9 (pressure relief components)
• ISO 16861 (DME fuel specification)
• ISO 3833 (vehicle types) and IEC 60529 (IP code)

Keywords: ISO 22760-4:2024, DME fuel system, dimethyl ether, level indicator, road vehicles, fuel level sensor, hydrostatic strength, insulation resistance, IP54.