First thing every morning I wash my hands under as hot of water as I can stand along with dish washing det that happens to be by the sink. Well we recently bought a new kind, Dawn with bleach alternative, no perfumes or dyes. Come to find out that you get at least a 5-10 pt false positive no matter how much you rinse your hands. This morning 92, alcohol rinse dry, 85. For the last 4-5 days I've repeated this every morning, FBG and predinner FBG same results. Just a heads up. Back to Ivory soap for me.