Liquid and vapor transfer connections for the industrial gases (Argon, Carbon Dioxide, Liquefied Natural Gas, Nitrogen, Nitrous Oxide, Oxygen)are specified in this standard. An obsolete/limited standard flanged connection system for oxygen, nitrogen, and argon is also specified. The specified connections are intended for use with liquid transport equipment, such as: cargo tanks, portable tanks, and railway tank cars, but do not apply to barges and marine tankers. Termination points at liquid production plants and on stationary storage vessels that directly interface with this transport equipment are also included. The connections in this standard are intended for use exclusively with the specified products. These connections are not intended for use on uninsulated or insulated (DOT 4L) cylinders, tubes, or on small equipment using connections less than 1 in (25 mm). The physical design of the fittings, other than the connection configuration at the coupling point, is also beyond the scope of this standard.
Specialized vacuum-jacketed bayonet connections, which are required for some cryogenic products, are not included in this standard.