Well, I have been using B401 to protect idle combs from severe wax moth damage. However, I recently discovered that if those combs are kept in supers, without covers, that rain can reduce the effectiveness of B401. I have two supers of idle combs, which remained perfectly fine for several months, with their thin coating of B401, applied in about April 2012. We've had a very rainy Summer, the best in quite a while. Now these two supers have their frames completely bound together, and bound to the inner super walls, with wax moth webbing and cocoons - yuk. In the future I plan to make sure all stored comb is kept covered from exposure to rain.