I am looking for some advise regarding bug bombs. We are battling some flea issues and almost have them licked. We want to set off a bomb to hopefully take care of the rest in the house. I am planning on taking all the animals out of the house but I was not sure what to do about the enclosure and residual odors. Will simply covering it with a sheet be sufficient. I was not sure if the bombs are a fine powder poison or a true gas that can permeate through the sheet. I believe the bombs say stay away for 3 hours then open windows to allow the house to air out for about 45 minutes but being February in Ohio that is not happening. Any advise will be greatly appreciated.