Overview
EN ISO 11114-5:2022 - “Gas cylinders - Compatibility of cylinder and valve materials with gas contents - Part 5: Test methods for evaluating plastic liners” - specifies laboratory and cylinder-level test methods to assess the compatibility of plastic liners used in composite gas cylinders and plastic matrix materials for Type 5 cylinders. The standard is intended to be used together with relevant design standards (for example ISO 11515, EN 12245) and addresses risks identified in ISO 11114-2. Note: compatibility issues between liners and some test fluids (e.g., water used in pressure testing) are explicitly excluded.
Key topics and requirements
- Scope and purpose
- Defines test methods to evaluate whether plastics are suitable for gas containment in composite and Type 5 cylinders.
- Focuses on material behaviour when in contact with gas contents (not water-test compatibility).
- Specimen and test arrangements
- Uses representative specimen types (e.g., disc samples) and prescribes test-bench setups for laboratory testing.
- Includes requirements for sample preparation and conditioning.
- Main test methods covered
- Permeation test - procedures, test-bench configuration, calculation of permeability coefficient, and interpretation of results.
- Swelling / blistering test - detection and recording of localized delamination or voids (blisters) and evaluation criteria.
- Ageing test - procedures to simulate gas exposure over time and record material property changes.
- Cylinder-level tests - liner collapse (under internal pressure below atmospheric), permeability of assembled cylinders, and combined collapse/blistering assessments.
- Evaluation and reporting
- Defines evaluation parameters and test-report content to support material qualification.
- Cross-references standard test methods for mechanical properties (normative references such as ISO 178, ISO 527, ISO 179-2, ISO 3167, ISO 8256).
Practical applications
- Who uses this standard
- Composite gas cylinder manufacturers and designers selecting or validating plastic liners.
- Type 5 cylinder manufacturers evaluating plastic matrix materials.
- Independent test laboratories performing compatibility and qualification tests.
- Certification bodies, conformity assessment organizations, and regulatory authorities.
- Why it matters
- Ensures safe long-term containment of gases by verifying liner resistance to permeation, swelling, blistering and collapse.
- Helps manufacturers choose appropriate plastics and design safe composite cylinder systems.
- Supports product certification and regulatory compliance for transportable gas cylinders.
Related standards
Keywords: EN ISO 11114-5:2022, gas cylinders, plastic liners, compatibility testing, permeation test, swelling, blistering, ageing test, Type 5 cylinders, composite cylinders, cylinder testing.
