During the last decades roadside advertising has become a major and rapidly expanding industry. Until the last decade, the extent of roadside advertising signs along rural roads has been strongly restricted in Scandinavian countries, mostly for safety reasons and aesthetic considerations. But growing pressure on road authorities caused by significant financial interests has resulted in a rapidly increasing number of advertising signs along rural roads.

The signs are placed at roadsides with the purpose of capturing and keeping driver attention. When the driver’s attention is captured, resulting in long eye glances in large horizontal angles away from the road, the time available for driver’s response to avoid a crash if something unexpected occurs is reduced. In this perspective, it is relevant to ask whether roadside advertising signs influence driver attention to such an extent that it affects road safety.

With the purpose of investigating, if and how, roadside advertising signs affect road safety a literature study followed by empirical studies has been carried out. The empirical studies were made by using an instrumented car equipped with a camera system to track eye movements, GPS for registration of speed behaviour, and laser scanner for measurement of distances to other road users. Registration data verifies whether the driver is looking at the advertising signs and the number of glances, - including glance duration and glance angles. Those measurements are related to driving speed and distances to other road users and thereby critical situations are detected.

The overall results of the empirical studies show that advertising signs do affect driver attention to the extent that road safety is compromised.