This part of ISO 11119 specifies requirements for composite gas cylinders up to and including 450 l water capacity, for the storage and conveyance of compressed or liquefied gases with test pressures ranging up to and including 650 bar 1. This part of ISO 11119 applies to: a) Fully wrapped composite cylinders with a non-load-sharing metallic or non-metallic liner (i.e. a liner that does not share the load of the overall cylinder design) and a design life from 10 years to non-limited life. For cylinders with a design life in excess of 15 years, re-qualification is recommended in order for these cylinders to remain in service beyond 15 years. The cylinders are constructed in the form of a liner over-wrapped with carbon fibre or aramid fibre or glass fibre (or a mixture thereof) in a resin matrix to provide longitudinal and circumferential reinforcement. b) Composite cylinders without liners (including cylinders without liners manufactured from two parts joined together) and with a test pressure of less than 60 bar. For cylinders with a design life in excess of 15 years, requalification is recommended in order for these cylinders to remain in service beyond 15 years. The cylinders are constructed: 1) in the form of a disposable mandrel overwrapped with carbon fibre or aramid fibre or glass fibre (or a mixture thereof) in a resin matrix to provide longitudinal and circumferential reinforcement; 2) in the form of two filament wound shells joined together. ISO 11439 applies to cylinders intended for use as fuel containers on natural gas vehicles. ISO 11623 covers periodic inspection and re-testing of composite cylinders. This part of ISO 11119 does not address the design, fitting and performance of removable protective sleeves. Where these are fitted they should be considered separately. 1 1 bar = 105 Pa.