Steels and hydrogen service

[DVNMech]

For a revamp of a plant, I need to select some pipe/fitting materials. Because some of the gases have a high hydrogen partial pressure, I've used the Nelson curves as a basis for material selection. Has anyone additional advice or guidelines for hydrogen service besides Nelson and API941?

 

[davefitz]

see thread124-92325 for H2 piping recommendations, espescially the NASA standards