Overview
EN ISO 11114-1:2020 - Gas cylinders: Compatibility of cylinder and valve materials with gas contents (Part 1: Metallic materials) provides requirements and compatibility data to help select safe combinations of metallic cylinder and valve materials for single gases and gas mixtures. Applicable to seamless metallic, welded metallic and composite gas cylinders (including tubes and pressure drums), the standard focuses on material/gas interaction risks during storage, transport and use of compressed, liquefied and dissolved gases. It is the third edition (2020), superseding the 2012 version and its 2017 amendment.
Key topics and requirements
- Material scope: Cylinder and valve metallic materials and acceptable combinations with gas contents.
- Compatibility criteria: Clear criteria to classify material/gas combinations as acceptable (A) or not acceptable (N) under normal service conditions.
- Corrosion mechanisms: Guidance on corrosion in dry and wet conditions, and corrosion from impurities.
- Hydrogen embrittlement: Identification and assessment of embrittlement risks for metals exposed to hydrogen-containing gases.
- Generation of dangerous products: Evaluation of chemical reactions that can form hazardous by-products.
- Violent reactions / ignition: Consideration of risks such as autogenous ignition in oxygen-rich environments (linked to Part 3 for non-metallic autogenous ignition testing).
- Stress corrosion cracking: Recognition and mitigation of SCC risks for cylinder materials.
- Compatibility tables and codes: Table 1 provides a gas-to-material compatibility matrix for single gases; guidance for mixtures is included. Annex A contains the NQSAB compatibility coding system.
- Definitions and roles: Defines key terms (e.g., competent person, dry) and specifies conditions (example: moisture limits to avoid condensation - 5 ppmV at 200 bar and −20 °C as illustration).
Practical applications and users
This standard is essential for:
- Cylinder and valve manufacturers selecting or qualifying metallic materials.
- Gas producers, packagers and transport companies ensuring safe cylinder/gas combinations.
- Design and R&D engineers assessing material selection for new gas applications.
- Certification, inspection and regulatory bodies referencing material compatibility for compliance.
- Safety managers and maintenance teams evaluating continued serviceability and risk mitigation (corrosion, embrittlement, ignition).
Use cases include material selection during design, establishing acceptance criteria for cylinder service, validating valve materials for specific gases, and informing transport and storage safety procedures.
Related standards
Keywords: EN ISO 11114-1:2020, gas cylinders, material compatibility, metallic materials, hydrogen embrittlement, corrosion, cylinder valve compatibility, gas mixtures, transportable pressure receptacles.
