In this high-floor trolleybus, four steps must be negotiated during entry and exit.
High-floor coach, giving three steps for entry and exit.

High-floor is an expression used to distinguish tram, light rail and other rail vehicles, along with buses and trolleybuses, built to formerly conventional design, from their counterparts of low-floor design.

A rail vehicle of high-floor design usually has a flat floor between 76 cm (30 in) and 137 cm (54 in) above the top of the railhead. For reasons of accessibility, an attempt is made to standardize the height, to allow a stair stepless entry from high platforms. The increased construction cost of high platforms, and the difficulty of making them compatible with other features of the urban landscape, are a significant obstacle to the conversion of existing tram networks into urban rail networks, particularly when many of the stations or stops are in the streets.

These problems were a major motivation for the development of low-floor trams, which allow transit operators to avoid the retrofitting of high platforms on existing routes, while still providing improved accessibility. However, for a newly constructed route, a route primarily located in tunnels, or a route with a dedicated right of way and enough space, high platforms are usually preferred, since high-floor vehicles are cheaper to manufacture, and have better operating characteristics.

High platforms do have significant advantages beyond wheelchair accessibility (except for double-decker trains). Mobility-impaired passengers (e.g. those using canes or who have difficulties climbing stairs) also benefit, as do travelers pulling wheeled luggage or small folding shopping carts. Even fully able-bodied passengers can board a railcar more rapidly if they do not have to climb stairs to enter, reducing dwell time at a stop, and reducing overall travel time. In addition, high-platform railcars have more floor space for passengers if space is not required for stairways, and wheelwells needed to accommodate railcar bogies.

Tourist coaches generally have very high floors, sometimes above 1 meter, in order to have ample room for luggage under the floor. Since boarding must be allowed directly from flat ground, long and steep staircases are needed.

Use in Germany

Today, in Germany, all rapid transit railways, most commuter trains, and many light rail vehicles operate as high-floor networks. A notable exception is the city railway in Cologne; in the mid-1990s, it was decided to divide that city's partially high platform network into two separate networks: high-floor and low-floor.

In contrast with some light rail underground lines, which are often provisionally equipped with low platforms or with tracks laid on raised ballast, there are new developments in the German cities of Düsseldorf (Wehrhahn line) and Dortmund (east-west line). In each of these cities, a new underground light rail line is equipped with platforms for low-floor trams and will be permanently operated with low floor vehicles. This form of design and construction will avoid the need for subsequent rebuilding of stops on tram routes, even though both cities already have underground lines with high-floor platforms.

See also

This article is based upon a translation of the German language version as at August 2011.

This article is issued from Wikipedia - version of the 8/2/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.