Overview
ISO 11623:2023 - "Gas cylinders - Composite cylinders and tubes - Periodic inspection and testing" defines requirements for periodic inspection and testing of hoop‑wrapped and fully‑wrapped composite cylinders and tubes (Types 2, 3, 4 and 5). The standard covers transportable cylinders with aluminium‑alloy, steel or non‑metallic liners or linerless construction, for compressed, liquefied or dissolved gases, with a water capacity from 0.5 L up to 3 000 L. ISO 11623:2023 is intended to verify cylinder integrity for continued service and to support safety, regulatory compliance and interoperability with UN model regulations.
Key Topics and Requirements
- Scope & applicability: Applies to cylinders constructed to ISO 11119‑1/2/3/4 and ISO 11515; may be applied to comparable designs with competent authority approval.
- Inspection procedures: Detailed procedures for external visual inspection, internal visual inspection, pressure testing, leak testing, and valve inspection.
- Preparation & identification: Requirements for cylinder identification, valve removal, cleaning, protective attachments (sleeves), and safe handling prior to inspection.
- Damage assessment & repairs: Criteria for categorizing external and internal damage, repairability limits, and when to render a cylinder unserviceable.
- Testing methods: Pressure test and leak test procedures and acceptance criteria to verify integrity for further service.
- Documentation & marking: Retest marking, record keeping, reference to next inspection date and re‑valving considerations.
- Safety & special procedures: Heat exposure considerations, handling of translucent cylinders, and safety precautions for inspection personnel.
- Supporting annexes: Annex A (inspection intervals), Annex B (damage criteria), Annexes C–F with guidance on translucent cylinders, corrosive gases, cleaning, and test date rings.
Practical Applications - Who Uses ISO 11623:2023
- Cylinder manufacturers - to define inspection regimes and after‑market support.
- Inspection and testing bodies / service stations - to perform compliant periodic inspections, pressure and leak tests.
- Gas suppliers & distributors - to ensure cylinders in their fleet meet regulatory safety requirements.
- Transport and logistics companies - for safe carriage of composite cylinders and tubes.
- Regulators and competent authorities - for authorizing alternative standards or special cases.
Using ISO 11623 helps reduce risk, extend service life where safe, and harmonize inspection practices internationally.
Related Standards
Normative and related references include: ISO 11119 (all parts), ISO 11515, ISO 10460, ISO 18119, ISO 11621, ISO 13341, ISO 22434, ISO 13769, ISO 7225, ISO 10286, and ISO 25760. These complement ISO 11623:2023 for design, valve handling, marking and material compatibility.
Practical takeaways: follow ISO 11623:2023 for standardized, safety‑focused periodic inspection and testing of composite gas cylinders and tubes to ensure regulatory compliance and safe continued service.
