OSHA requirements are set by statute, standards and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you can consult OSHA's website at https://www.osha.gov.

December 14, 1993

Mr. Paul J. Plaisance, Jr.
Office of Technical Management
Petroleum Reserve
Department of Energy
Washington, DC 20585

Dear Mr. Plaisance:

This is in response to your August 31 letter, requesting an interpretation of the Process Safety Management (PSM) of the Highly Hazardous Chemicals, 29 CFR 1910.119, standard. Specifically you requested clarification as to whether the Strategic Petroleum Reserve (SPR) storage sites, described in the "SPR Cavern Operations Summary" enclosed in your letter, are covered by the PSM standard. Please accept our apology for the delay in responding.

Storage of 10,000 pounds (4535.9 kgs) or greater amounts of flammable liquids, including crude oil, is covered by the PSM standard unless excepted by 1910.119(a)(1)(ii) or (a)(2). In the SPR summary you disclosed that diked well pads are only occupied by workers for occasional inspection and maintenance activities and may be normally unoccupied remote facilities. Whether SPR sites would be considered normally unoccupied remote facilities and therefore not covered by the PSM standard by 1910.119(a)(2)(iii), must be determined by evaluation of each work site. This evaluation must consider diked well pads in the context of the entire work site. We strongly recommend that you carefully consider the definition of "process" and "normally unoccupied remote facility" and refer to the preamble to the PSM Final Rule which provides clarification on the intent of these definitions when evaluating SPR work sites.

The preamble to the Final Rule on page 6372 provides OSHA clarification in that the Organization Resource Counselors noted that "normally unoccupied remote facility" is not meant to apply to an area that is located in a distant corner of a large facility. Rather, it is meant to apply to a facility that is so far removed from any other facility that it could not contribute to a catastrophic release. Also in the preamble on page 6372, the Chemical Manufacturers Association notes that normally unoccupied remote facility means a facility which is operated, maintained and serviced by employees based at a different location and who visit the remote facility to perform periodic tasks. Remote facilities are not within the boundaries of (nor are they contiguous to) other operations of the employer. OSHA agrees with these notes. Accordingly in the PSM Final Rule, the definition of "normally unmanned remote facility" was clarified to emphasize that the facility must be remote and the word "unmanned" was changed to "unoccupied" to better reflect OSHA's intent.

The SPR cavern operation summary states that over 99% of the SPR oil is stored in caverns and the remaining oil is stored in surface or atmospheric tanks or in pipelines as pipeline pack. Please note that the exception at 1910.119(a)(1)(ii)(B) does not apply to all flammable liquids stored in atmospheric tanks or transferred which are kept below their normal boiling point without benefit of chilling or refrigeration. This exception is limited to flammable liquids in atmospheric tanks, containers and pipes used only for storage and transfer (to storage) and not connected to a process or process vessel.

As you may be aware, the Department of Transportation's (DOT's) Office of Pipeline Safety (OPS) generally regulates pipeline facilities and the transportation of hazardous liquids, including crude oil. Such regulatory coverage by another federal agency always holds the possibility of preemption of OSHA authority. However, in a March 27, 1990 letter, (copy enclosed) DOT's Office of the General Counsel stated that OPS could not assert jurisdiction over SPR facilities because of the definition of "person" contained in the Hazardous Liquid Pipeline Safety Act of 1979 (HLPSA), 49 USC app. 2001 et seq.. In short, the term "person" was never intended to apply to the Federal Government; hence, it cannot be an owner or operator of a pipeline facility within the meaning of HLPSA. Thus it is OSHA's regulatory scheme which must control.

Thank you for your interest in occupational safety and health. If we may be of further assistance, please contact us.


Roger A. Clark, Director
Director of Compliance Programs