I am thinking of blowing cellulose into an existing wall for sound proofing. It is not fool proof but I have to jump thought a lot of hoops in order to take the wall down. I have a couple of questions and wonder if you all could answer them. 1. I read that cellulose can be dusty after it is put in but it clears out later on. I am allergic to dust, will this have any long term impact? 2. I read fiber glass is a better at sound proofing but isn't more dangerous. 3. Could there be any leakage? Would my next door neighbor be effected?