Proposal of New Star Rating Bands for iRAP on Two-lane Rural Roads in Ecuador

Abstract

The iRAP model aims to reduce the number of road accidents or their severity by assigning a Star Rating (SR) to every 100 m of the road. The SR were derived from accident statistics and studies from several countries and organizations. However, these results may not be applicable to other countries or regions due to differences in the safety of vehicles and the behaviour of road users. This research proposes new iRAP Star Rating (SR) bands for two-lane rural roads in Ecuador. The study analysed more than 600 kilometres on the country's road network and estimated the SRS values every 100 m after collecting the road infrastructure attributes that could impact the likelihood of severity of a crash. The iRAP results were compared with the actual traffic accidents in the country, and, after statistical analysis, the study proposed new thresholds that better fit the Ecuadorian data. This process can be used by other countries to calibrate their own thresholds.