The existing PSM standard applies in part to processes involving a flammable liquid or gas on site in one location in a quantity of 10,000 pounds or more. However, the existing PSM standard contains an exemption for
“[f]lammable liquids stored in atmospheric tanks or transferred which are kept below their normal boiling point without benefit of chilling or refrigeration.” 29 CFR §1910.119 (a)(1)(ii)(B).
OSHA is considering clarifying this exemption in response to a decision by an Administrative Law Judge of the Occupational Safety and Health Review Commission. In Secretary of Labor v. Meer Corporation, No. 95-0341 (OSHRC 1997), an administrative law judge ruled that PSM coverage does not extend to flammables stored in atmospheric tanks, even if the tanks are connected to a process. As a result, employers can exclude the amount of flammable liquid contained in an atmospheric storage tank, or in transfer to or from storage, from the quantity contained in the process when determining whether a process meets the 10,000-pound threshold quantity. On May 12, 1997, OSHA issued a Regional Administrator’s memorandum acknowledging this decision (OSHA, 1997). The Meer decision was contrary to OSHA’s earlier interpretation of subsection (a)(1)(ii)(B), which was that the standard covered all stored flammables when connected to or located in close proximity to a process. The Meer decision was relevant in the Motiva refinery explosion and fire in Delaware City, DE, in 2001, and in an explosion at National Vinegar Company in Houston, TX in 1997.