there is also the option of weight system dump. upon finding an unconcious diver you flip them face up remove there weight belt (pockets) and as you ascend dump gas from there bc as needed (control your own bc as per normal ascent). If they begin to ascend to fast (with no air in there bc they will tend to only gradualy float depending on exposure suit) but if they do you simply release them, they will make it to the surface and you can follow at a safe ascent rate.
food for thought
food for thought