Progress: Addressed, Not Adequately
DOT Relevance: 192.51 192.65
Purity requirements for hydrogen are most stringent for electronics industry consumers. Current industrial hydrogen grades are specified by both CGA (G-5.3 Commodity Specification for Hydrogen) and ISO (14687 Hydrogen fuelProduct specification) though industrial gas companies often establish their own grading systems. Vehicular fuel quality is being addressed by SAE and ISO. SAE has published J2719 Information Report on the Development of a Hydrogen Quality Specification for Fuel Cell Vehicles and is developing a hydrogen fuel specification though it is anticipated that it will be several years before one is complete. ISO is developing fuel cell application hydrogen specifications for incorporation into ISO 14687.
Subpart B (Materials) of 49 CFR 192 prescribes the minimum requirements for the selection and qualification of pipe and components for use in pipelines.
It is unclear precisely what the final fuel quality requirements will be in a more developed hydrogen economy.
Sandia National Labs has identified this as a topic that must be researched if a full characterization of hydrogen effects on structural materials can be considered complete.
ASME B31.12 has no plans to incorporate purity issues at the present time.
Further research is needed on this key topic. Standards for hydrogen piping materials should take into account hydrogen purity effects. All standards established should be incorporated by reference into the federal code.