Speed limits and warnings

Situation-specific speed limits and warnings


Apr 2016

When it comes to infrastructure, however, measures have to encompass a lot more than just the road design. Given that excessive speed is a common cause of accidents, other measures that can be taken include management of traffic flows and suitable speed management. Whether variable speed limits, warnings of adverse weather conditions and traffic jams, lane closures, information about public transport or advice on alternative routes to avoid traffic jams, the examples show the huge potential offered by dynamic signage systems designed to influence traffic. Future interaction between vehicles and traffic computer systems (Rural Road 4.0) will far exceed what we are familiar with today.

The benefits are clear: Speed limits, warnings and information can be activated in specific situations so that only the most relevant information is instantly conveyed to drivers, who no longer have to select and categorize the information they process. As a result, static displays such as 80 km/h in wet conditions, 100 km/h between 10 p.m. and 6 a.m. or risk of traffic jams can be replaced with an effective alternative. In addition, targeted speed limits can help to prevent traffic jams. If the volume of traffic increases further along the road, leading to an increased risk of a traffic jam, the volume of approaching vehicles can be curtailed by reducing the speed limit accordingly. Not every traffic jam can be avoided in this way, but it does at least ensure the best possible traffic flow for the current traffic density.

Of course, this can work only if all road users take notice of the specifications, but experience consistently shows that variable speed limits have a higher level of acceptance than static displays.