ASME B31.12 Standard on Hydrogen Piping and Pipelines contains requirements for piping in gaseous and liquid hydrogen service and pipelines in gaseous hydrogen service. The general requirements section covers materials, brazing, welding, heat treating, forming, testing, inspection, examination, operating, and maintenance.  The industrial piping section covers requirements for components, design, fabrication, assembly, erection, inspection, examination, and testing of piping.

This Code is applicable to piping in gaseous and liquid hydrogen service and to pipelines in gaseous hydrogen service. B31.12 is applicable up to and including the joint connecting the piping to associated pressure vessels and equipment but not to the vessels and equipment themselves. It is also applicable to the location and type of support elements, but not to the structure to which the support elements are attached.