Small passages are like most others except that they are shorter and only certain characters can enter them. Small passages run horizontal, as opposed to narrow passages, which run verticle. They are often composed of the same black material which makes up most of the game's world.
Small passages pose no threat, but only a hinderance in progression in the game. It blocks taller characters, such as Claire or Grey, from moving further along in a given level and requires certain characters to access them.
Overcoming small passages are a simple task. A certain character must be brought to the small passage and enter, exiting on the opposite side of the passageway. Only small characters can be used to enter a small passage.