Vertical wheelchair lifts that travel a greater distance are required to be fully surrounded by walls, for safety reasons. The lower landing must have a full height door. When the door is closed, it must be flush with the interior walls of the enclosure. The upper landing is required to have a gate or door that also closes flush with the inside walls. Again, these are safety features. Both the doors must also have interlocks, preventing access when the lift is not at the landing.