I have a contractor who's saying that a recently installed pre-fab building at a project site is missing firestop protection at pre-wired conduit penetrations on an electrical panel. We're using RGS for the work. I've only heard of conduit penetrations through walls and floors, but never at panelboards. I've searched the NEC, the NEC handbook, the forum and online conduit manufacturing company sites, but have come up with nothing. Is this even a requirement, becuase I'm not so sure? Appreciate the guidance.