Specifies minimum requirements for certain aspects concerning material, design, construction, and workmanship, manufacturing processes and test at manufacture of refillable gas cylinders of a test pressure not greater than 75 bar, and of water capacities from 1 up to and including 150 L for compressed, liquefied or dissolved gases, exposed to ambient temperatures. Comprises definitions and symbols. Annex A gives a special prototype test. An example of acceptance certificate is included in annex B.