I wear a half mask that covers just my nose/mouth/face and neck area. Kinda like the one milkman ( http://www.rei.com/product/725711 ) wears. i suppose you could just cut a hole in the mouth area? I mean its already got breathing holes....supppose one big hole won't ruin it. But if you want the mouth to be open only for drinking, you could easily just flip the mask up and put it back down.