ISO 21010:2017

Overview

ISO 21010:2017 - Cryogenic vessels: Gas/material compatibility - defines requirements and test methods for assessing gas/material compatibility in cryogenic vessels and associated equipment. The standard focuses on materials that are or could be in contact with cryogenic fluids, giving general guidance for compatibility with gases and detailed requirements for oxygen and oxygen‑enriched atmospheres. It does not cover mechanical properties for low‑temperature applications.

Key topics and requirements

• Scope and focus

  • Compatibility criteria for materials in contact with cryogenic fluids, with emphasis on oxygen service.
  • Excludes mechanical/structural property requirements.

• Material evaluation

  • Distinguishes metallic and non‑metallic materials (plastics, elastomers, lubricants, ceramics, glasses, adhesives).
  • Notes that fully oxidized materials (e.g., ceramics, glass) present low ignition risk if uncontaminated.
  • Thin metallic materials (<0.1 mm) and combustible non‑metallics require special testing or avoidance.

• Oxygen compatibility principles

  • Assessment based on minimum ignition temperature and likely ignition energy sources (friction, compression, particle impact, static, electric arc, internal flexing).
  • Operating conditions to consider: pressure, temperature, gas velocity, oxygen concentration/state, and surface contamination (see ISO 23208).

• Defined test methods

  • Spontaneous ignition (bomb) test - Annex B; measures spontaneous ignition temperature (SIT) in pressurized gaseous oxygen. SIT minimums increase with pressure (e.g., ~200 °C at 3 bar rising to 400 °C at high pressures).
  • Pressure surge test - Annex C; acceptance requires no reaction after two sets of five consecutive pressure surge impacts at maximum working pressure.
  • Insulation tests
    • Mechanical impact in liquid oxygen (LOX) - impact energy criterion and series testing.
    • Hot‑wire test - glowing wire in 100% oxygen to verify insulation does not sustain combustion.
  • Alternative acceptance: demonstrated long‑term satisfactory service or a favorable risk assessment.

• Additional guidance

  • Annex A lists metallic materials commonly used for liquid oxygen service.
  • For gases other than oxygen, guidance refers to ISO 11114‑1 and ISO 11114‑2.
  • Caution: for severe conditions and pressures above 40 bar, additional testing beyond the standard is advisable.

Applications and users

ISO 21010:2017 is intended for:

• Manufacturers and designers of cryogenic vessels, valves, hoses and vaporizers
• Materials and reliability engineers assessing oxygen compatibility
• Safety and compliance teams in industrial gas, medical oxygen, aerospace and LNG sectors
• Test laboratories performing SIT, pressure surge, LOX impact and insulation tests
• Procurement and certification bodies setting acceptance criteria for cryogenic equipment

Related standards

• ISO 23208 - Cleanliness for cryogenic service
• ISO 10297:2014 - Gas cylinders - Cylinder valves (references pressure surge testing)
• ISO 11114‑1 / ISO 11114‑2 - Guidance for gases other than oxygen

Keywords: ISO 21010:2017, cryogenic vessels, gas/material compatibility, oxygen compatibility, liquid oxygen (LOX), spontaneous ignition test, pressure surge test, insulation test, cryogenic fluids.