Do the tapered threads on conduit fittings listed for hazardous locations need to comply with all aspects of ASME B1.20.1? I've found that the female threaded hubs on conduit outlet bodies are sometimes tapped much larger than allowed under ASME B1.20.1. When checked with a NPT plug gage, the gage stops as much as 3 threads beyond the "L1" notch, i.e. 2 threads over tolerance. In such cases, a properly threaded male fitting can bottom out in the cast portion of the hub before the threads become even hand tight. I've also checked the male threads with a ring gage on conduit fittings and found similar non-compliance. My concern is that such problems might prevent sealing in wet locations, and perhaps compromise the flame path.