The population is aging all over the world and the proportion of seniors is increasing from 10 to 20 % of the total population. The number of serious injuries due to crashes increases from about 50 crashes per billion km for the age groups from 25 to 65 years old to more than 250 crashes per billion km for the older age groups. The impact of older drivers on road safety is due predominantly to age-related impairments. Considering the difficulties, both in gaining older drivers’ compliance with safety measures and in avoiding difficult driving situations, and considering the limited effectiveness of additional in-vehicle devices, this paper proposes to enhance the safety of the infrastructure for elderly people. Studies examining roadway characteristics have mainly focused on intersections. Here, the roadway geometry has been analyzed. Two stretches of a very hazardous road were simulated using an interactive driving simulator. Two age groups of young and older drivers were tested. The speeds of younger and older drivers were compared along the roadway. The understanding of the road was also assessed through a comparison of the two age groups. It was found that, if the geometry of the roadway is complex and tortuous, the speeds of older subjects are generally much lower than the speeds of younger subjects. The dispersion of speeds is always much greater for older rather than for younger drivers. From the outcomes of this study, the self-understanding road is expected to be self-understanding for both younger and older drivers, but at a different level. Younger drivers make more correct manoeuvres than older drivers. This study concludes that the older drivers experience more difficulties in understanding roadway geometry.
Keywords: road safety; older drivers; driving simulation; self-understanding road; roadway design