Abstract: The disclosed apparatus make possible the maintenance, repair, alteration, and upgrade of walls and wall mounted facilitates within hospitals and cleanrooms while occupying a minimum area. In one embodiment the apparatus is a six-sided box with an open side, a transparent side, and a side with two hand ports. To operate, the apparatus is placed, from the open side, against the wall or the wall facility that needs repair or upgrade. Afterwards the air inside the apparatus is vacuumed to lower the air pressure with respect to the surrounding pressure before the hands of a repairman enters the apparatus through the two hand ports. Repair can start at this time while the apparatus maintains a negative inside air pressure and while no particles of contaminants can escape the apparatus. The vacuumed air may be released back into the room or hallway after it is filtered.