Overview
EN ISO 21058:2021 - Road vehicles: Dimethyl Ether (DME) refuelling connector specifies design, construction and testing requirements for refuelling connectors (nozzles and vehicle receptacles) used with Dimethyl Ether (DME, referred to as D15). Adopted by CEN from ISO 21058:2019, this European Standard applies only to devices built from new, unused parts and to connectors with standardised mating components. It is intended to ensure safe, compatible and interoperable DME refuelling across vehicles and dispensers while preventing misfuelling with other gaseous fuels.
Key topics and technical requirements
The standard covers the following technical areas and mandatory topics:
- Scope & definitions - applicability limited to DME (D15) and devices meeting ISO 16861 fuel specification.
- General construction - materials, geometry and standardised mating profiles for nozzles (dispenser side) and receptacles (vehicle side).
- Dimensions & profiles - standard receptacle profile and critical nozzle dimensions to ensure cross‑manufacturer compatibility.
- Safety features - mechanical and design requirements to prevent refuelling with other gaseous fuels.
- Marking & instructions - required labels, identification and user/service instructions.
- Comprehensive test program, including:
- Impact resistance (nozzle and receptacle)
- Leakage tests (room, low/high temperatures)
- Abnormal loads and pressurised/unpressurised conditions
- Torque limits for mounting hardware
- Durability: endurance, corrosion resistance, material compatibility, ozone ageing, thermal cycling
- Hydrostatic strength, vibration resistance, creep, fluid exposure and electrical continuity
- Annexes - critical nozzle dimensions and recommended production test plans.
Applications and users
EN ISO 21058:2021 is practical and actionable for:
- Vehicle OEMs designing DME‑powered vehicles and integrating receptacles.
- Fuel dispenser and nozzle manufacturers producing DME refuelling hardware compatible with standard receptacles.
- Component suppliers and material engineers validating material compatibility and corrosion resistance for DME exposure.
- Testing laboratories and certification bodies performing conformity testing, durability and safety assessments.
- Infrastructure planners and fleet operators deploying DME refuelling stations and ensuring interoperability and safety.
- Regulators and standards committees harmonising fuel system safety requirements.
Related standards
- ISO 21058:2019 (original international standard adopted as EN ISO 21058:2021)
- ISO 16861 (Dimethyl Ether fuel specification referenced in this standard)
- Prepared by ISO/TC 22 (Road vehicles), SC 41 (gaseous fuels) and adopted by CEN/TC 301.
Using EN ISO 21058:2021 helps ensure safe, interoperable DME refuelling hardware, reduces misfuelling risk and streamlines market acceptance of DME vehicle and dispenser components.
