I am not an EMT but I saw an off duty E.M.T. giving a guy who had passed out while jogging C.P.R. When he did the mouth to mouth part he had taken a clear plastic mouth gaurd thing out of his fanny pack. It was triangular in shape. Can a none E.M.T. by these somewhere to keep in his truck in case he learns C.P.R. This must be to protect form desieses. When I was in junior high a guest speeker firefighter said he was giving a guy mouth to mouth and the guy regained conciouseness and threw up into his mouth. Are there any documented cases of someone getting AIDs or Hepititis from giving C.P.R. ?