[Gary Dillard]

I understand your frustration Joe.

2 things. First - R72-C says "rated" but it doesn't specify which rating (operating pressure, proof pressure, burst pressure, fatigue pressure are all defined by NFPA), so that is the only issue up for debate. I'm going with the interpretation that the documentation I have from SMC is adequate to say that these valves can be safely operated up to 125 psi. It says the proof pressure is 1.5 times the maximum operating pressure and that the valve can sustain that pressure for 1 minute and still function normally afterward.

Second - Regardless of the ruling, it doesn't make this or any valve "illegal". It just means you need to have an additional pressure relief valve downstream of the regulator, set above the regulator pressure and below the "rated" pressure (R72-C). You should already have a procedure for verifying and adjusting the KOP valve per update 11 (see rule R77, latest version), so use last year's KOP valve, dial it down to below 100 psi, put in a tee and put it in line.