This International Standard specifies requirements for single or two-stage pressure regulators for connections to gas cylinders normally used for compressed gases up to 300 bar1) (30 MPa), for dissolved acetylene, for liquefied petroleum gases (LPG), methylacetylene-propadiene-mixtures (MPS) and carbon dioxide (CO 2 ) used in welding, cutting and allied processes. 1) 300 bar relates to maximum cylinder charging pressure at 15 °C.