Establishes the minimum criteria for the design, material, workmanship and construction, manufacturing tests and processes of refillable transportable seamless steel gas cylinders of water capacities between 0,5 l and 150 l, for liquefied, dissolved and compressed gases. Applies to stainless steel cylinders with an Rm value less than 1100 MPa. Suitable also for the manufacture of cylinders with a water capacity less than 0,5 l.