Hi, Boys and Girls: I'm new. We bought a bag of DE and we were going to just fill a large, shallow pan with it so the chickens could fluff in it if they wanted. Is that ok.? It comes with all sorts of warnings on it and so my husband is concerned. Our 14 year old son is the poultry manager. And would be handling the stuff. I noticed some of you mentioned dust masks, which we have, but are they good enough?