Elliot, you appear to be doing some kind of bargaining with yourself. In making a kayak a person does far more than glassing "once every couple years", in fact if wouldn't be out of the question for a person to be exposed to epoxy everytime they were working on their kayak. So not using a respirator as you mention in a previous thread may not cause you to be sensitized this year, but you don't know. In that sense Rob Macks post is applicable, there are uncertainties about individual sensitization and severity of reaction, given the experiences of others there is no risk to protecting yourself. There is a risk in not taking precautions. I figure if my eyes become bothered by epoxy vapors when glassing large areas then the mucus membranes inside of my body don't need the grief as well. I would take Liz Leedhams post to heart. I also met a gentleman that made two s&g kit kayaks, on the second one he absentmindedly layed his forarm on fresh epoxy, his rash was like the worst poison oak. I met another that did the same but used no precautions, he couldn't work in the presence of epoxy at all. In my unscientfific opinion if avoiding contact with epoxy is paramount but then how innocuous can the vapors be?