My official question to OSHA was…
Recently, OSHA issued an LOI aligning with NFPA 350 regarding PRCS isolation. In particular, OSHA stated that a pipe passing through a PRCS but not terminating within the space would NOT have to be isolated and evacuated. I want to know if this practice would be acceptable if the employer were to "reclassify" the PRCS to non-PRCS using 1910.146(c)(7) or 1926.1203(g). Both of those standards state that there can not be a known or "potential" atmospheric hazard. Having a 1" liquid NH3 line with about 2,000 pounds inside the space, inside piping/tubing that was not installed per ASME B31.3 or 31.5, and is not in an inspection/testing program because the facility is NOT a PSM/RMP facility, is a SUPER RISKY approach to reclassifying a PRCS. According to Merriam-Webster, "potential" is defined as "
existing in possibility; capable of becoming or developing into something in the future".
With the material in the piping inside the space, is there not a "potential", therefore, the space would not be eligible for "reclassification"? Maybe we could leave the piping charged with the hazardous chemical and do the entry as a "permitted entry" with all of the requirements of (d)-(k) in place?
OSHA’s response: (emphasis by me)