Specialized expertise is required to answer this complex question. In this two-part article, I will discuss the Meer Corp. court decision, its impact on OSHA's Process Safety Management of Highly Hazardous Chemicals (PSM) standard, and what it means for your business and documentation requirements.
First, let's review some background on the Meer court decision (Secretary of Labor v. Meer Corp., OSHRC Docket No. 95-0341). In 1995, Meer Corp. in New Jersey faced numerous citations under the PSM standard (29CFR1910.119). The company challenged some of these citations on the basis that OSHA was overreaching when applying the PSM standard to atmospheric storage tanks, which are defined as having a design pressure between atmospheric pressure and half a pound per square inch gauge (psig). Standard 29CFRR1910.119(a)(1) states that this section of the code is applicable to a "process which involves a Category 1 flammable gas (as defined in 1910.1200(c)) or a flammable liquid with a flashpoint below 100 [degrees] Fahrenheit (37.8 [degrees] Celsius) on-site in one location, in a quantity of 10,000 pounds (4,535.9 kilograms) or more except for [â¦] flammable liquids with a flashpoint below 100 [degrees] Fahrenheit (37.8 [degrees] Celsius) stored in atmospheric tanks or transferred, which are kept below their normal boiling point without benefit of chilling or refrigeration."
The decision further deliberated on the interpretation of the word "process." Ultimately, the federal court decision limited the applicability of the PSM requirement to exclude only tanks that are neither refrigerated nor holding toxic materials, nor part of the process. On May 12, 1997, OSHA issued a memorandum affirming it would abide by the ruling until the standard is revised:
"Coverage under OSHA's [PSM] (1910.119) does not extend to stored flammables in 'atmospheric tanks,' even if they were connected to a 'process' within the definition of the standard. [â¦] OSHA will abide by the Meer decision and will not cite 1910.119 under circumstances when coverage of the process would be based partly or solely on the quantity of flammable liquid in connected atmospheric storage tanks, that would otherwise qualify for the 1910.119(a) (1)(ii)(B) exemption. Citations under 1910.119 will continue to be issued when the quantity of flammables in the process, not counting atmospheric storage, exceeds 10,000 pounds, or where the quantities in storage do not fall within the exception for other reasons (i.e., storage not atmospheric, storage relies on refrigeration, quantities not actually in storage, etc.)."
The above guidance and interpretation may lead an organization to avoid documenting the pressure-relief requirements for nonrefrigerated atmospheric storage tanks containing flammable liquids meeting the exemption above. This avoidance could happen for various reasons (e.g., cost savings, lack of expertise, etc.). However, meeting the requirements of the PSM standard is not the only reason to evaluate the overpressure protection requirements for these tanks. The flammable liquids code 29CFR1910.106 and the EPA Risk Management Plan Rule also require detailed design documentation for tanks.
Additionally, other decisions have found that storage tanks "integrally involved" in a process are not exempt. What does it mean for a tank to be "integrally involved"? Answering the question requires knowing more than just the defined process boundary limits; for example, operation of the equipment in a manner equivalent to a feed-surge vessel (see "Feed Tank" and "Day Tank" in the included figure) could be considered integrally involved.
In other words, tanks that are in toxic service, refrigerated, designed for greater than one-half psig of pressure or integral to the process are covered by PSM, and the pressure-relief system shall be evaluated and documented accordingly.
In the next issue of BIC Magazine, I will detail other issues and complexities of this decision and what they mean for facilities processing hazardous chemicals.
For more information, visit www.smithburgess.com or call (713) 802-2647.
