Fuels like gasoline are exempt from OSHA process safety management (PSM) requirements. When asked about the applicability for hydrogen storage larger than 10,000 lb (4500 kg) being used as a fuel, OSHA responded with an interpretation that can be found at https://www.osha.gov/laws-regs/standardinterpretations/2013-02-04-0  

The interpretation says in part “…processes containing a threshold quantity of hydrogen used as a fuel must meet all requirements of PSM.”

NFPA 2 Annex G provides a summary of the conflicts with 29 CFR 1910.103. This is language that has been in NFPA 55 for several cycles as this conflict has existed for many years. The requirements in the Federal Regulations were established in the early 1970s. Since that time, OSHA has not had sufficient resources to update the applicable provisions.

The primary difference between OSHA and NFPA requirements is the separation distances for bulk hydrogen storage systems. The separation distances were changed by NFPA several years ago based on scientific analysis of leak data. When evaluating installations involving CFR referenced standards such as the ASME Boiler and Pressure Vessel Code, OSHA inspectors are taught to accept compliance with later editions of the standards as meeting the requirements of the regulation. The same may be true for the differences between OSHA 49 CFR 1910.103 and NFPA 2.

See attached response from OSHA on the general topic of NFPA codes/standards.