INTEGRATING HUMAN FACTOR EVALUATION IN THE DESIGN PROCESS OF ROADS - A WAY TO IMPROVE SAFETY STANDARDS FOR RURAL ROADS

Each year between 40 and 50 thousand people are killed and more than 3 million are injured due to road traffic accidents in both the United States and the European Union. In Europe 99 percent of fatal transportation accidents are road traffic related and about 95 percent of all factors contributing to road crashes are attributed to human factors. However, research with respect to accident causes clarifies, that it is not always one single factor that causes the accident, but a considerable amount of them are originated from a combination of human errors, and the road itself. Furthermore, it is known that, in principle, road design is a powerful instrument to influence road user behavior. Thus, this study will primarily focus on the interaction between road environment and road user behavior to develop appropriate design alternatives for improving road safety. A brief worldwide review of geometric highway design guidelines revealed that most standards include human factor issues only implicitly. This paper describes a methodology, developed on the basis of an International research project financed by the University of Catania and by the Italian University Ministry. The aim of the research project is to improve highway design standards for road safety with respect to human factors needs. An evaluation system to quantify driver mental workload is provided. A variety of research methods and research instruments were applied. The field data were collected by using an instrumented car traveling under real traffic conditions on two-lane rural roads. The car was equipped with a GPS receiver, vehicle speed- and acceleration sensors, a video camera for recording the driver's view and a system to record psycho-physiological responses (i.e. Electrocardiogram ECG, Electroculogram EOG, Electrodermal Activity EDA, Electromiography EMG). A survey was conducted on roadway sections to provide a representative sample of Italian two-lane rural roads. Based on this experience a procedure was developed to distinguish between good and poor driving conditions.