Wheelchair lifts, also referred to as platform lifts, are vertical elevating systems with a platform designed to transport a single passenger between floor levels. Some manufacturers provide units that can travel up to a maximum of 14 feet, but shorter vertical distances (less than one floor) are typical. Wheelchair lifts are typically provided as a prefabricated, self-contained system that can be located indoors or outdoors. They can be installed in an enclosed vertical shaft to provide weather protection, if necessary, or they can be left unenclosed. Like traditional passenger elevators, the wheelchair lift system must meet all the requirements of the ADA.