This position points to the clauses in NFPA 2 and NFPA 55 that allow equivalent protection methods for hydrogen supply system separation distances. Extensive work by an NFPA hydrogen storage task group has developed revised liquefied hydrogen supply system separation distances and associated controls (such as retention valves at hydrogen fueling stations).
The current NFPA 2:2020 distances are the historical distances that match those in NFPA 55. The revised distances will be published in the next edition of NFPA 2, which will be released in August 2023 as NFPA 2:2024.
Before the August 2023 release of NFPA 2:2024, users can use the NFPA equivalency clause to request a variance and use the technical reasons as substantiation for the revised separation distances that are available from NFPA’s web site. This position includes links to the appropriate NFPA documents that can be used as rationale for the variance.
Nonmembers may access a free copy @ https://www.cganet.com/cga-issues-position-statement-on-liquified-hydrogen-supply-system-separation-distances/