ISO 13985:2006

Overview

ISO 13985:2006 - Liquid hydrogen - Land vehicle fuel tanks specifies construction, material and test requirements for refillable cryogenic fuel tanks that store liquid hydrogen and are permanently attached to land vehicles. The standard defines safety- and performance-driven requirements and testing methods to provide a reasonable level of protection against loss of life and property from fire, explosion and other hazards related to liquid hydrogen vehicle fuel systems.

Key topics and technical requirements

• Scope and applicability: Applies to refillable, permanently mounted liquid hydrogen fuel tanks for land vehicles.
• Design and materials: Inner tanks must be suitable for cryogenic service (design temperature references and operation down to the boiling point of hydrogen). Materials must demonstrate hydrogen compatibility and low-temperature toughness (references to ISO 21028-1). Outer jacket materials must preserve insulation integrity.
• Mechanical and thermal stresses: Inner-tank pressure testing formula and margins are specified; tanks and jackets are designed for specified outer pressures. Ambient and operating temperature ranges are defined (e.g., −40 °C to 85 °C; provisions for up to 120 °C in engine compartments). Design must account for thermal stresses produced at −253 °C (liquid hydrogen temperature).
• Structural integrity and crash loads: Mounting and supports must absorb prescribed accelerations for vehicle categories without structural damage; support stresses are limited (e.g., not to exceed 50% of minimum ultimate tensile strength under acceleration conditions).
• Insulation and thermal autonomy: Insulation performance requirements are referenced (ISO 21014); thermal autonomy (time until inner-tank pressure reaches MAWP from liquid-hydrogen boil-off) is used to evaluate insulation quality.
• Accessories and compatibility: Requirements for pressure-relief devices, level gauges and other accessories; materials must be compatible with hydrogen and typical vehicle fluids.
• Testing and inspection: Type tests (design approval, burst pressure, thermal autonomy, maximum filling, accessory tests), routine tests (pressure, leak testing, weld inspection), and marking/labeling requirements are specified.

Applications and who uses it

ISO 13985:2006 is used by:

• Fuel tank manufacturers and fabricators designing cryogenic liquid hydrogen tanks for vehicles
• Automotive OEMs integrating hydrogen fuel systems into passenger and commercial vehicles
• Hydrogen system designers (fuelling interfaces and boil-off management)
• Test laboratories and certifying bodies conducting type and routine tests
• Regulators and safety engineers assessing compliance with cryogenic hydrogen vehicle safety standards

Implementing ISO 13985 helps ensure safe, reliable liquid hydrogen vehicle fuel tanks, consistent testing procedures, and improved crash, thermal and pressure performance.

Related standards

• ISO 13984 - Liquid hydrogen - Land vehicle fuelling system interface
• ISO 21014 - Cryogenic vessels - Cryogenic insulation performance
• ISO 21028-1, ISO 21029-1, ISO 21013-3 - Cryogenic vessel material, design and pressure-relief guidance
• ISO 23208 - Cleanliness for cryogenic service

Keywords: ISO 13985:2006, liquid hydrogen, land vehicle fuel tanks, cryogenic fuel tanks, fuel tank testing, thermal autonomy, hydrogen compatibility, pressure relief, insulation.