I dont know if this has been talked about or not, or if it was ever considered in the script drafts and just left out for story sake, but a light bulb popped up above my head at about 1am this morning and I wish I had some way to contact Saul, Victor, Micheal, and CJ. So here it goes...

Outdoors/Hunting stores these days sell many products designed to prevent human scent from escaping. Products such as Scent-Lock, Dead Downwind, Scentblocker, etc. These would be perfect for use knowing that the zombies of the story are attraced to human scent. Even the Post Exchange/Base Exchange sometimes carry these lines of clothes. Ok.. so if they don't have access to them then CBRN suits should also work. The suits are used when in a nuclear, chemical, or biological environment and are lined with activated charcoal. They also contain human scent. You know this if you ever spent 3+ days wearing them. You sweat like crazy, but noone smells you. I wonder why once they figured out the "sweat bombs" worked that they didn't put it together.

Just a thought. Sure would be one fine way to sit somewhere with your rifle picking off zombies or mallers and when they started getting close lock the door and sit quietly and not have to worry about them smelling you and trying to get through the door.