49 CFR 173.311 — Metal Hydride Storage Systems.

The following packing instruction is applicable to transportable UN Metal hydride storage systems (UN3468) with pressure receptacles not exceeding 150 liters (40 gallons) in water capacity, and having a maximum developed pressure not exceeding 25 MPa. UN Metal hydride storage systems must be designed, constructed, initially inspected, and tested in accordance with ISO 16111:2018 (IBR, see § 171.7 of this subchapter), consistent with § 178.71(m) of this subchapter. Until December 31, 2026, UN Metal hydride storage systems may instead conform to ISO 16111:2008(E) (IBR, see § 171.7 of this subchapter). Steel pressure receptacles or composite pressure receptacles with steel liners must be marked in accordance with § 173.301b(f), which specifies that a steel UN pressure receptacle displaying an “H” mark must be used for hydrogen-bearing gases or other gases that may cause hydrogen embrittlement. Requalification intervals must be no more than every five years, as specified in § 180.207 of this subchapter, in accordance with the requalification procedures prescribed in ISO 16111:2018 or ISO 16111:2008.