This European Standard sets out minimum requirements for the material, design, construction and workmanship, manufacturing processes and tests at manufacture of refillable transportable seamless steel gas cylinders of water capacities from 0,5 litres up to and including 150 litres for compressed, liquefied and dissolved gases. This standard is applicable to cylinders with a value of Rm max. <= 1 100 MPa. It does not cover cylinders with diameters > 140 mm where either Rm max. > 1 300 MPa or the design wall thickness > 12 mm. It also does not cover cylinders with diameters <= 140 mm where either Rm max >= 1 400 MPa or the design wall thickness >= 6 mm, because beyond these limits additional requirements could possibly apply. NOTE 1 For compatibility with the intended gas service and operational conditions, of grades and strength ranges of steels used for cylinder manufacture, see 4.1.4. NOTE 2 This standard is also suitable for the manufacture of cylinders of water capacity less than 0,5 litre.