More info on radiation hazards. See bulletins #65 and #56. I don't know if they are up to date, but they ought to be. I see no rules for anything below 300 Kc. Bulletin #63 has a very nice part 15 chart of uses, emission limits, etc. http://www.fcc.gov/oet/info/documents/bulletins/ Dale Rice Williams, OR HiFer DER 13561.61