Overview
EN ISO 11118:2025 - "Gas cylinders - Non-refillable metallic gas cylinders - Specification and test methods" (ISO 11118:2025) is a CEN-adopted international standard that defines requirements for the material, design, manufacture, inspection and testing of non-refillable metallic gas cylinders. Applicable to welded, brazed or seamless cylinders used for compressed and liquefied gases, the standard also covers non-refillable sealing devices and their prototype tests. Note that national or other international rules may further restrict which gases can be used in cylinders conforming to this standard.
Key applicability limits:
- Test pressure (ph) for liquefied gases ≤ 250 bar and for compressed gases ≤ 450 bar;
- Or ph × water capacity (V) ≤ 1 000 bar·litres;
- For ph > 45 bar, water capacity V ≤ 5 litres.
Keywords: EN ISO 11118:2025, non-refillable metallic gas cylinders, specification and test methods, gas cylinders, sealing devices.
Key Topics
- Materials: Requirements for carbon/low-alloy steels, aluminium/alloys, and austenitic stainless steels, including chemical composition constraints.
- Design & Calculation: Pressure-containing parts, design drawings and engineering controls for safe construction.
- Construction & Workmanship: Accepted construction types (welded, brazed, seamless), non-refillability measures, and pressure-relief device requirements.
- Prototype and Batch Testing:
- Material and tensile tests
- Burst and drop tests
- Proof pressure and leak testing
- Valve-to-cylinder interface verification
- Inspection & Quality Control: Type approval procedures, batch tests, tests on every cylinder, inspection criteria and permitted repairs.
- Sealing Devices: Specifications and normative prototype testing requirements (see Annex A).
- Marking & Certification: Mandatory manufacturing and operational markings, type approval certificates, and certificates of conformance.
Applications
EN ISO 11118:2025 is essential for organizations involved in:
- Manufacturing non-refillable metallic gas cylinders and closures
- Pressure vessel and gas cylinder design and engineering
- Factory and independent testing laboratories performing prototype, batch and per-cylinder testing
- Certification and type approval bodies and national regulators
- Gas suppliers, distributors and downstream users needing compliant single-use gas cylinders for industrial, medical, leisure or specialty gas applications
Practical benefits include improved product safety, consistent quality assurance, traceable markings and harmonized test methods that facilitate market access across CEN/ISO jurisdictions.
Related Standards
- Supersedes EN ISO 11118:2015 and EN ISO 11118:2015/A1:2020
- Prepared by ISO/TC 58 and CEN/TC 23; implementers should check national adoptions and any additional regulatory requirements (transport, gas-specific regulations).
For manufacturers and conformity assessors, EN ISO 11118:2025 provides the authoritative requirements and test methods for compliant non-refillable metallic gas cylinders.