December 8, 2000

Mr. Edwin G. Foulke, Esq.
Jackson, Lewis, Schnitzler & Krupman
2100 Daniel Building
301 North Main Street
Greenville, SC 29601-2122

Dear Mr. Foulke:

We are writing in response to correspondence received from your client, Thomas Industrial Gases, Inc. (Thomas), concerning an issue arising under the Occupational Safety and Health Administration's (OSHA's) rule on Process Safety Management of Highly Hazardous Chemicals; Explosives and Blasting Agents, (PSM), 29 CFR §1910.119. Thomas requested an interpretation which would include its MAPP gas glass mold lubrication system within an exemption from the requirements of OSHA's PSM rule.

MAPP gas is a flammable gas made from a mixture of methyl acetylene and propadiene. We understand Thomas' customers are storing quantities of MAPP gas in amounts greater than the threshold quantity (TQ) of 10,000 pounds, which would trigger application of the PSM requirements. We have reviewed and considered a number of letters from you and your client to OSHA staff providing information in connection with Thomas' interpretive request. The letters are dated from December 20, 1999 through November 8, 2000.

It appears that your client's concerns were spurred by a prior OSHA interpretation letter to Mr. Steven Lee, Libbey Glass, Inc., dated November 23, 1999. Libbey Glass, Inc. is one of Thomas' primary users of this process. In this letter, OSHA concluded that Libbey's use of Thomas' MAPP gas process to lubricate glass molds did not meet the hydrocarbon fuels exemption set forth in PSM [29 CFR §1910.119(a)(1)(ii)(A)] because MAPP gas, in this process, was not being, "used solely for workplace consumption as a fuel [emphasis added]."

You provided additional technical information to OSHA which shows MAPP gas is: 1) used as a hydrocarbon fuel (flammable gas) in your MAPP gas processes; and 2) consumed on-site as a fuel for the purpose of heating glass molds. PSM-covered processes exist when your customers'/employers' MAPP gas processes contain 10,000 pounds or more of MAPP gas.

Based on your additional technical information, we have concluded that Thomas' MAPP gas glass mold heat processes fall within the hydrocarbon fuels exemption to PSM. Please note, however, that if employers utilize your MAPP gas system as part of a process containing another highly hazardous chemical covered by the standard, the hydrocarbon fuels exemption would not be available for your MAPP gas system.

Based on the foregoing, OSHA will rescind its November 23, 1999 letter to Mr. Steven Lee, Libbey Glass, Inc., on this issue.

Thank you for your interest in occupational safety and health. We hope this provides the clarification you were seeking and regret any confusion the earlier document may have caused. As this letter demonstrates, OSHA's re-examination of an issue may result in the clarification or correction of previously stated enforcement guidance. 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 http://www.osha.gov. If you have any further questions, please feel free to contact the Office of General Industry Compliance Assistance at (202) 693-1850.

Sincerely,

R. Davis Layne
Deputy Assistant Secretary