I can't tell you how many times I go to dump trub and yeast from my conical fermenters and forget to open or remove the airlock. As a result, a small amount of Starsan can get sucked into the fermenter. I tried putting a sticky note on the side of the fermenter, but that never worked. Finally, last night, it hit me to put caps on the dump valves which I can't miss. These caps came with my sanitary valves, so they were just laying around anyway.