ISO 20766-22:2025

Road vehicles - Liquefied petroleum gas (LPG) fuel system components - Part 22: Power supply bushing (fuel pump/actuators/fuel level sensor)

This document specifies general requirements and definitions for power supply bushing (fuel pump/actuators/fuel level sensor), a liquefied petroleum gas (LPG) fuel component, intended for use on the types of motor vehicles defined in ISO 3833. It also provides general design principles and specifies requirements for instructions and marking. This document is applicable to vehicles (mono-fuel, bi-fuel or dual-fuel applications) that use gaseous fuels in accordance with ISO 9162. It is not applicable to: - fuel containers; - stationary gas engines; - container mounting hardware; - electronic fuel management; - refuelling receptacles. Miscellaneous components not specifically addressed in this document can be examined for conformity with the criteria of any applicable part of the ISO 20766 series, including testing to the appropriate functional tests. All references to pressure in this document are considered gauge pressures unless otherwise specified. This document applies to devices that have a service pressure in the range of 110 kPa (butane rich at 20 °C) and 840 kPa (propane rich at 20 °C). Other service pressures can be accommodated by adjusting the pressure by the appropriate factor (ratio).

Véhicules routiers — Équipements pour véhicules utilisant le gaz de pétrole liquéfié (GPL) comme combustible — Partie 22: Douille d'alimentation (pompe à carburant/actionneurs/capteur de niveau de carburant)

General Information

• Status: Published
• Publication Date: 05-Mar-2025
• ICS: 43.060.40 - Fuel systems
• Technical Committee: ISO/TC 22 - Road vehicles
• Drafting Committee: ISO/TC 22 - Road vehicles
• Current Stage: 6060 - International Standard published
• Start Date: 06-Mar-2025
• Due Date: 17-Jan-2026
• Completion Date: 06-Mar-2025

ISO 20766-22:2025 Overview

ISO 20766-22:2025 is an international standard developed by ISO that specifies requirements for power supply bushings used in liquefied petroleum gas (LPG) fuel system components in road vehicles. This part 22 of the ISO 20766 series focuses on power supply bushings related to fuel pumps, actuators, and fuel level sensors designed for motor vehicles as defined in ISO 3833. The document outlines general design principles, safety requirements, marking, and testing methods applicable to LPG fuel system components operating under specific pressure ranges.

This standard applies broadly to mono-fuel, bi-fuel, and dual-fuel vehicles utilizing gaseous fuels according to ISO 9162, but it excludes fuel containers, stationary gas engines, container mounting hardware, electronic fuel management, and refuelling receptacles. Devices covered typically operate within service pressures from 110 kPa (butane rich) to 840 kPa (propane rich).

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Key Topics in ISO 20766-22:2025

• Scope and Application
  Defines the types of vehicles and fuel systems applicable, emphasizing LPG-powered road vehicles. The focus is on safety-critical power supply bushings serving fuel pumps, actuators, and sensors within LPG fuel systems.

• Marking and Identification
  Components must bear clear and indelible markings including manufacturer name, model number, working pressure and temperature ranges, fabrication date, and electrical ratings if relevant. Recommended markings include fuel type, certification symbols, type approval numbers, and references to this ISO document.

• Construction and Assembly Requirements
  The power supply bushing must resist maximum operating pressures and temperature ranges without compromise. Electrical safety is critical, so insulation requirements to prevent sparks are emphasized, including isolation resistance above 10 MΩ and system isolation from the vehicle body. Hermetic sealing to ensure tight and isolated electrical connections is mandatory.

• Testing Procedures
  The standard mandates rigorous testing, including:

  • Hydrostatic strength testing at 2.25 times working pressure inside the LPG tank
  • Leakage, temperature (high/low), and corrosion resistance testing
  • Electrical tests such as insulation resistance and overvoltage
  • Material compatibility tests for non-metallic and brass parts
    These tests ensure conformity to safety and performance standards under varied operational conditions.

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Practical Applications

• Vehicle Manufacturers and Component Designers
  ISO 20766-22:2025 guides the development and approval of LPG fuel system components, ensuring safety and reliability of power supply bushings interacting with fuel pumps, actuators, and sensors.

• Quality Assurance and Compliance
  Inspection bodies and certification agencies utilize this standard to verify marking legibility, construction integrity, electrical safety, and environmental robustness of LPG fuel system components.

• Maintenance and Service Providers
  Proper identification and adherence to the specified testing help in assessing component condition, ensuring safe replacements or repairs in LPG-powered vehicles.

• Fuel System Integrators
  The standard supports integration of LPG supply components in vehicles adapting to mono-fuel, bi-fuel, or dual-fuel LPG systems, facilitating compatibility with existing vehicle fuel infrastructures compliant with ISO 9162 and ISO 3833.

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Related Standards

• ISO 20766 Series
  Other parts of the ISO 20766 series elaborate on LPG fuel system component requirements, test methods, and functional evaluations relevant to various fuel system parts beyond power supply bushings.

• ISO 3833
  Defines vehicle types and terminology essential for understanding the application scope of power supply bushings in LPG-fueled road vehicles.

• ISO 9162
  Specifies properties and classifications for gaseous fuels, particularly LPG, ensuring that power supply bushings are designed for compliant gas types and service pressures.

• IEC 60529
  Provides the classification for degrees of protection (IP codes) for electrical enclosures, referenced in the standard to define protection levels for power supply bushings installed in vehicle compartments.

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ISO 20766-22:2025 plays a crucial role in standardizing power supply bushing components within LPG fuel systems, promoting safety, durability, and interoperability across the automotive industry’s use of gaseous fuels. Manufacturers, regulators, and service professionals benefit from its comprehensive approach to design, marking, and testing, ensuring LPG-powered vehicles operate reliably and securely in the global market.

Standards Content (Sample)

International
Standard
ISO 20766-22
First edition
Road vehicles — Liquefied
2025-03
petroleum gas (LPG) fuel system
components —
Part 22:
Power supply bushing (fuel pump/
actuators/fuel level sensor)
Véhicules routiers — Équipements pour véhicules utilisant le gaz
de pétrole liquéfié (GPL) comme combustible —
Partie 22: Douille d'alimentation (pompe à carburant/
actionneurs/capteur de niveau de carburant)
Reference number
© ISO 2025
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Markings . 2
5 Construction and assembly . 2
6 Tests . 3
6.1 Applicability .3
6.2 Hydrostatic strength .3
Bibliography . 4

iii
Foreword
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This document was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 41, Specific
aspects for gaseous fuels.
A list of all parts in the ISO 20766 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
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