ASME BPVC Section IX / ASME B31.1

ASME BPVC Section I PG-71 / ASME B31.1 Section 122.6

This fails code on multiple counts. First, ASME Section I PG-71.4 prohibits reducing the discharge pipe below the area of the PRV outlet — the 2-inch to 1.5-inch reduction restricts flow and creates excessive back pressure on the PRV, reducing its relieving capacity. Second, the discharge termination at 4 feet above ground level creates a scalding hazard to personnel in the equipment yard; discharge must be directed to a safe location where personnel cannot be exposed to the steam release. Third, the horizontal discharge piping without a drain will accumulate condensate, which can cause water hammer when the PRV lifts. PRV discharge piping must be self-draining with a drip pan elbow or weep hole at the low point per ASME B31.1 Section 122.6.

ASME BPVC Section I PG-71.2

ASME BPVC Section I strictly prohibits any intervening stop valve between a boiler and its pressure relief valve. A closed block valve renders the PRV inoperable, allowing boiler pressure to exceed the maximum allowable working pressure (MAWP) and potentially causing a catastrophic boiler explosion.

ASME BPVC Section IV / ASME B31.1

This fails code. ASME Boiler and Pressure Vessel Code Section IV (Heating Boilers) and ASME B31.1 require a safety relief valve on the low-pressure side of every pressure reducing valve station. The safety valve must be set at or below the MAWP of the downstream equipment (30 PSI in this case). If the PRV fails open, full upstream pressure (150 PSI) would reach equipment rated for only 30 PSI — a catastrophic overpressure event. This is one of the most critical safety lessons taught at every UA local.

ASME BPVC Section VIII / OSHA 1910.169

This passes code requirements. The tank has proper ASME Section VIII certification with National Board registration as required by OSHA 1910.169. The PRV is correctly set at the MAWP of 200 psig, satisfying ASME Section VIII UG-134 which requires the relief device to be set at or below the MAWP. The automatic condensate drain and pressure gauge are operational requirements for reliable compressed air service. The annual external inspection meets the minimum inspection frequency required by most jurisdictional authorities. Note that internal inspections may also be required at intervals determined by the jurisdiction and the tank's corrosion history.

ASME BPVC Section VIII Div. 1 / OSHA 1910.169

All pressure vessels including compressed air receivers must bear an ASME Section VIII nameplate with National Board (NB) registration number, MAWP, manufacturer data, and serial number. An unregistered vessel cannot be legally operated and may not have been properly designed, fabricated, or tested per ASME code.

ASME BPVC Section VIII UG-134 / OSHA 1910.169(b)

ASME Section VIII requires the pressure relief device on a vessel to be set at or below the vessel's maximum allowable working pressure (MAWP). A PRV set above MAWP provides no overpressure protection, risking catastrophic vessel failure. The PRV set pressure must never exceed the MAWP stamped on the nameplate.