ISO 11623:2015

Overview

ISO 11623:2015 - Gas cylinders - Composite construction - Periodic inspection and testing - defines requirements for the periodic inspection, testing and integrity verification of transportable composite gas cylinders. It applies to hoop‑wrapped and fully‑wrapped composite cylinders (Types 2, 3, 4 and 5) with aluminium‑alloy, steel or non‑metallic liners or linerless construction, intended for compressed, liquefied or dissolved gases. The standard covers cylinders with a water capacity from 0.5 L up to 450 L and, as far as practicable, can be applied to smaller cylinders when authorized.

Key topics and technical requirements

ISO 11623:2015 focuses on the practical steps and criteria needed to requalify composite cylinders for continued service. Key technical topics include:

• Scope and applicability - cylinder types, liner materials and water capacity limits.
• Periodic inspection objectives - verification of cylinder integrity prior to return to service.
• Inspection procedures - preparation, visual and dimensional examination of composite overwrap and liner interfaces.
• Testing methods - mandated tests to detect leakage or loss of strength and to confirm fitness for service (standard describes required types of tests and their intended purpose).
• Acceptance and rejection criteria - documented criteria for determining when cylinders can be requalified or must be condemned.
• Documentation and marking - recording inspection results, requalification markings and traceability.
• Applicability to constructions built to ISO 11119 - explicitly written to address cylinders manufactured to ISO 11119‑1, ISO 11119‑2 and ISO 11119‑3, and may be used for other comparable designs with competent‑authority approval.

(Note: ISO 11623:2015 defines the framework and requirements but implementers must consult the full text for exact test procedures and criteria.)

Practical applications - who uses ISO 11623:2015

ISO 11623:2015 is used by organizations and professionals involved in the life‑cycle management of composite gas cylinders:

• Cylinder manufacturers and designers (for post‑manufacture inspection regimes)
• Accredited inspection and testing laboratories and requalification centers
• Gas suppliers, distributors and cylinder fleet operators (periodic maintenance policies)
• Transport and logistics companies handling pressurized gases
• Regulatory and competent authorities that authorize application to non‑ISO constructions

Using ISO 11623 helps ensure safe, consistent requalification of composite cylinders, reduce in‑service failures, and support regulatory compliance.

Related standards

• ISO 11119‑1 / ISO 11119‑2 / ISO 11119‑3 - composite cylinder design and construction standards (ISO 11623 is written to inspect cylinders built to these standards).

Keywords: ISO 11623:2015, composite gas cylinders, periodic inspection and testing, ISO 11119, requalification, hoop‑wrapped, fully‑wrapped, cylinder inspection, composite cylinder integrity.