SWOV positions

4 December 2007

As of 1 January 2008, it will no longer be compulsory for motorists in Austria to drive with their lights on. Apparently, an Epigus Institut study has a shown that daytime running lights (DRL) is less safe in traffic rather than safer. Since the introduction of compulsory DRL, Austria is supposed to have seen an increase of 65% in motorcycle crashes. This gave SWOV, which is in favour of DRL, every reason to examine the Austrian government's sources.

The Epigus study states that DRL is particularly unsafe for pedestrians and motorcyclists. A 65% increase in motorcycle crashes since DRL was made obligatory in Austria was even mentioned. However, there is also a study of the Austrian road safety research institute 'Kuratorium für Verkehrssicherheit' which actually reports a total reduction of 1500 crashes. SWOV enquiries showed that this study, which was commissioned by the Austrian Ministry of Transport, unfortunately had not yet been published.

The Austrian Ministry of Transport used the Epigus Institut study to justify its decision. This is supposed to have shown that DRL causes two-wheelers and pedestrians to be less conspicuous. After having studied this report, SWOV concludes that the study was not an accident study that can show how DRL has affected road safety. For example, the conclusions state that DRL has no safety benefits in good weather, but does indeed prove to be effective when the weather is bad. In exceptional cases people and vehicles are obscured. The Epigus study mainly consisted of an observation of viewing behaviour in traffic.

It must be concluded that the ministry has interpreted the results of this study very freely.

We also conclude that the ministry is not opposed to DRL as long as the intensity of light is reduced.

Studies in countries where DRL is obligatory [for more details see our Fact sheet entitled Daytime Running Lights (DRL)]  have shown that DRL has a neutral effect on motorcyclists i.e. it has neither positive nor negative effects. Concerns about motorcyclists being less conspicuous because their lights would have to compete with those of cars when DRL is compulsory, are unnecessary.

Although Austria will repeal the DRL obligation on 1 January, it is not opposed to DRL. In the same press release the Austrian Ministry of Transport announces that it will support the introduction in the EU of low-energy DRL units which are also less blinding. These should be mounted as a standard accessory on new cars. SWOV of course supports this intention.  

None of the currently available sources give SWOV any reason to doubt the previously demonstrated positive road safety effect of DRL. Drivers who manually switch on their lights during daylight hours ensure that they are more conspicuous, thus contributing towards a reduction in the number of traffic casualties. The safety effects of compulsory DRL are 15% fewer deaths, 10% fewer severely injured, and 5% fewer slightly injured. Based on the crash data for 2006, the introduction of DRL in the Netherlands would save about 35 road deaths.

DRL is already compulsory to different extents in various European countries.