Does PSM apply to hydrogen fueling or refueling stations with more than 10,000 lb. of hydrogen onsite? Some have suggested that H2 fueling stations are exempted, but that seems incorrect.

There is no generalized exception for hydrogen fueling stations.  However, PSM is intended for employee protection. It’s not intended for retail operations or customers. Through paragraph 1910.119 (a)(2)(1) of the regulation, PSM exempts retail facilities. Some may use this exemption as a means to exclude H2 retail fuel sites from PSM.

Fuel stations that are non-retail, such as those that might supply forklifts, transit buses, or an in-house fleet of trucks, would still require PSM compliance if the 10000 lb. threshold is exceeded. Fuel stations that sell to the general public, such as light duty vehicle stations and truck stops, are retail facilities and may qualify for an exemption. There is no defined term for “retail,” so some subjectivity exists with regard to the type or amount of retail activity that would be required for this exemption.  It is not directly applicable, but parallel language in the EPA’s Risk Management Program (RMP) regulation states that a facility must be at least 50% retail to qualify for a retail exemption.

While it’s possible to avoid PSM regulation by maintaining total site inventory below 10000 lbs. and/or applying a retail exemption, the principles of PSM are sound. There is value to adopting the PSM principles to all systems and it’s  a best practice to apply to all hydrogen systems regardless of quantity or exemption status. However, many want to avoid the regulatory risk of additional scrutiny and being subject to audits. Most fuel stations to-date have managed to stay below the 10000 lb. threshold, but it’s expected that station size will grow as the market for heavier vehicles develops.