Evaluation of road safety measures appears to be the weakest component of road safety management systems in Europe. To improve Road Infrastructure Safety Management, road authorities, road designers and road safety practitioners need prediction tools, commonly known as Accident Prediction Models (APMs), allowing them to analyze the potential safety issues, to identify safety improvements and to estimate the potential effect of these improvements in terms of crash reduction. Within the above context, the objective of this paper is to present a synthesis of current practices in APMs based on both the results of a relevant survey and an extensive literature review conducted within the PRACT project. In order to present a complete overview of currently used Accident Prediction Models (APMs) by different National Road Administrations (NRAs) in Europe and worldwide, as well as the currently used data sources for the development and application of APMs a relevant survey was completed. A questionnaire was specially designed and dispatched to several NRAs in Europe and worldwide, in order to collect detailed information on APMs developed and used by them. Furthermore, a review of relevant international literature was carried out, with focus particularly on identifying those modelling approaches and specific models that may be applicable or transferable in the European context. On the basis of the questionnaire data and of the literature review results, a synthesis of current practices regarding APMs has been developed, as a basis for the identification of the most usable models as well as for the implementation of a web based APM repository. In total, 23 questionnaires were collected from 18 European countries, USA and Australia, and were analysed with the aim of reviewing and assessing existing APMs, in terms of theoretical approaches, characteristics of the models in use, implementation conditions, data requirements and available results, with focus on motorways and higher ranked rural roads. It was found that, despite recent advances, most National Road Administrations (NRAs) and other organisations do not systematically use such methods during decision making for the implementation of road safety treatments

The tunnel lighting system is an important factor affecting driving safety, but it also represents the most expensive operative cost of a tunnel. Conventional tunnel lighting systems have been progressively replaced by LED lighting systems. This technology is spreading fast because of its low energy consumption and the high durability combined with low maintenance requirement. Aim of this research was to assess, by means of driving simulator experimentation, the impact of the LED lighting system on traffic safety. The driver performance approaching inside and exiting LED lighted tunnels was analyzed and compared to the behavior maintained in tunnels illuminated with a traditional system, in normal and in critical conditions. Thirty-one young participants drove through two different virtual scenarios while data on their speed, lateral position, and reaction in front of a sudden obstacle in the carriageway were collected. A statistically significant difference was revealed as a function of the type of lighting; simulated LED lights often induced a better driving behavior under some aspects. The motorists were able to perceive in advance the critical situation and the consequent maneuvers were carried out in a more effective way. Moreover, drivers kept better their lateral trajectory control in transition areas.

This paper presents a comprehensive literature review on road traffic accident prediction models (APMs) and crash modification factors (CMFs). The focus is on motorways and higher ranked rural roads and the study was performed within a European road authorities' research project. The priorities for the review were determined by a questionnaire survey on model availability and needs, addressed to national road authorities in Europe and worldwide. The salient literature was reviewed and existing models were assessed in terms of theoretical approaches, model characteristics, implementation conditions, data requirements and available results. The review of CMFs focused on their background and development, the various methods for developing them and the key issues in their application. The review resulted in the development of an APM and CMF inventory that forms the basis for an online repository, with the aim of assisting the practical application of gathered experience on accident prediction.