Anyone have any suggestions on how to start the process of becoming certified to build j-boxes and control enclosures, where I can placethe cert sticker on the box? I have been using several box mfgrs. to provide this service, but their delivery schedule and sometimes arrogant attitude is driving me to look at other options. I use mainly small explosion proof boxes and increased safety enclosures from Stahl, Weiemuller, ABTECH, etc. which need ZONE certification when built.