Transportable gas cylinders. Specification for the design and construction of refillable transportable seamless steel gas cylinders of water capacities from 0,5 litre up to and including 150 litres. Cylinders made of seamless stainless steel with an Rm value of less than 1 100 MPa|Hydraulic tests, Approval testing, Defects, Compressed gases, Gas storage, Rejects, Design, Hardness testing, Certificates of conformity, Transportable, Gas pressure vessels, Visual inspection (testing), Re-usable, Gas cylinders, Materials specification, Quality, Pressure vessels, Burst tests, Dissolved gases, Volume, Pressure, Marking, Pressure testing, Gases, Mechanical testing, Ultrasonic testing, Water, Steels, Stainless steels