Back-welding of threaded connections in anhydrous ammonia service.

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.

January 31, 1991

Mr. Robert Brenton Director,
Tech Services Distribution Facilities
CF Industries, Inc.
Salem Lake Drive
Long Grove, Illinois 60047

Dear Mr. Brenton:

This is in response to your letter of December 7, 1990, which pertained to back-welding of threaded connections in anhydrous ammonia service in compliance with the latest American National Standards Institute (ANSI) standard, published in 1989. We apologize for the delay in our response.