ISO 11119-3:2020

Overview

ISO 11119-3:2020 - "Gas cylinders - Design, construction and testing of refillable composite gas cylinders and tubes - Part 3" defines minimum requirements for fully wrapped fibre‑reinforced composite gas cylinders and tubes (type 4 and type 5) with either non‑load‑sharing metallic/non‑metallic liners or without liners. It covers cylinders and tubes up to 450 L water capacity, intended for the storage and conveyance of compressed or liquefied gases, and specifies a minimum design life of 15 years. Cylinders manufactured to this standard are not intended for toxic, oxidizing or corrosive gases.

Key topics and technical requirements

• Scope and applicability
  • Type 4: fully wrapped composite cylinders with a non‑load‑sharing liner.
  • Type 5: fully wrapped cylinders without liners (test pressure < 60 bar).
  • Fibre reinforcement: carbon fibre, aramid fibre, glass fibre, or mixtures within a matrix.
• Materials and construction
  • Requirements for liner materials (where used) and composite overwrap materials.
  • Matrix and fibre selection, workmanship and manufacturing process controls.
• Design submission and approval
  • Documentation and prototype testing requirements for type approval and new designs.
• Inspection, testing and batch control
  • Prototype and batch tests include: proof pressure, hydraulic elastic expansion, burst tests, ambient and environmental cycling, vacuum, flaw testing, drop/impact, high‑velocity impact (gunfire), fire resistance, permeability, leak tests, pneumatic cycle, liner burst, resin shear strength and glass transition temperature.
  • Marking, traceability and documentation requirements for manufacture and batch inspection.
• Limitations
  • Not covering removable protective sleeves, nor intended for corrosive/oxidizing/toxic gases.

Practical applications and users

• Manufacturers and design engineers of composite gas cylinders and pressure vessels use ISO 11119-3 for product design, material selection and production quality control.
• Test laboratories and certification bodies apply the standard for type approval, prototype testing and batch inspection.
• Transport and storage operators, industrial gas suppliers, and energy/utility companies rely on the standard to ensure safe cylinder use for compressed and liquefied gases.
• Regulators and procurement teams reference the standard for compliance with UN Model Regulations on the transport of dangerous goods and for harmonized international requirements.

Related standards

• ISO 11119 series (other parts covering design/testing variations)
• ISO 11439 - cylinders for natural gas vehicle fuel containers
• ISO 11623 - periodic inspection and re‑testing of composite cylinders
• References to ISO test methods for materials (e.g., tensile, hardness standards)

Keywords: ISO 11119-3:2020, composite gas cylinders, fully wrapped cylinders, type 4, type 5, carbon fibre, aramid fibre, glass fibre, cylinder testing, gas storage, compressed gases, liquefied gases.