Telematics
Traffic telematics offer several options for significantly lowering accident numbers. Compared to the previously used methods, the advantage consists of better cost efficiency and higher acceptance of traffic rules and information adapted to match requirements.
Corridor control systems
In some EU countries for several years, on problematic motorway stretches local control has been installed, i.e. the speed limit is adapted as a function of traffic density, traffic flow and weather. The display is made with variable message signs, and additional information (e.g. tailback) is also given in order to achieve better acceptance. The experiences show that the number of accidents is reduced by between 25 and 40 percent. There are also positive effects against tailbacks.
Intelligent speed adaptation
While most current "intelligent" applications are focussed on motorways, there are hardly any approaches on how to tackle built-up areas, where over half of all accidents happen. The exception is "intelligent speed adaptation" (ISA), which results in a reduction in accident numbers by 25 percent in built-up areas. The drivers are informed through audible and light signals about the locally determined speed limit, and, if they exceed it, they are warned, for example, by increased resistance from the accelerator pedal. This is a voluntary driver assistance system, not a speed limiter. In an emergency, acceleration beyond the speed limit is possible at all times.
The first tests were made in Sweden, Holland and Great Britain. The result was not only an improvement in safety but also surprisingly high approval from the test drivers. ISA is a relatively low-cost addition to the classical methods of road design.
Dynamic warnings
Where classical measures have turned out to be ineffective, intelligent warning systems (dynamic messaging) will increasingly be deployed for the improvement of locations where many accidents occur. This allows speed-dependent or possibly vehicle-dependent warnings to be displayed at accident-prone locations (e.g. on bends in out-of-town areas) (Example: Lorry drivers change down a gear!).
Section Control
Speed monitoring on sections of motorway has turned out to be particularly successful. On certain motorway sections, the average speed of individual vehicles is calculated and if the limit is exceeded the number plate is read and a penalty is sent automatically. In the Vienna Kaisermühlentunnel, Austria's first section control installation was constructed for approximately € 1.5 million.
When the situation before and after were compared, this caused the average speed to drop from 85 to 75 km/h. And the particular positive effect was that in the first year after commissioning the section control, in five accidents nobody died and the seriousness of injuries was much reduced on account of the lower speed (seven slightly injured). The cost of these accidents to the economy was, in this period, only € 60,000. If the cost and the benefit are compared, this installation saves fives times what it would have cost in accidents and damage to the environment.
The section control installation in the change-over area of the A2 monitors the allowed 130 km/h for cars, 100 km/h for busses and 80 km/h for lorries when the road is dry. If it starts to snow or rain, the speed limits are reduced by means of variable message signs to 80 km/h and are monitored.
In the meantime, a mobile section control for the monitoring of construction sites is also in use – from March to September 2005 on the A1 near Sattledt and from November on the A10 in Kärnten (planned by autumn 2007). In 2006 a further section control is to be constructed on the S16 in Vorarlberg.
