Aerial devices are vehicle-mounted, elevated and rotating work platforms. OSHA defines a vehicle as, "any carrier that is not manually propelled," and a platform as, "any personnel-carrying device (basket or bucket that is a component of an aerial device." Vehicle-mounted devices-telescoping, articulating or both - used to position personnel are considered aerial devices. This includes extensible and articulating boom platforms, aerial ladders, vertical towers and a combination of any of the above. The George Washington University developed the Aerial Lift Program to ensure that these devices are properly used and personnel are appropriately trained.