Evaluating Road Infrastructure Safety in Bamenda, Cameroon: A Data-Driven Approach Using Reactive Safety Performance Indicators and iRAP Star Ratings

Abstract

With over 1000 road traffic fatalities recorded annually in Cameroon, the absence of the implementation of effective road safety measures remains a pressing concern. This study assesses the safety of road infrastructure in Bamenda using a data-driven approach that combines reactive safety indicators with iRAP star ratings to identify high-risk crash locations. After analysis of crash data and site visits, four indicators, with three being reactive (crash frequency, crash rate and injury severity index) and one proactive (iRAP star ratings) were calculated. The correlation between these indicators were also evaluated. Out of 64 evaluated sites (40 road segments and 24 intersections) with varying risks, 4 locations were identified for priority interventions as they had the highest risk based on all indicators. These sites had a mix of vehicle types with vulnerable road users, poor road geometry and unsafe road sides and speeding risks. The correlation between indicators varied, indicating the complementary nature of reactive and proactive assessments. The study highlights the added value of integrating the two approaches, both historical crash data and forward-looking infrastructure assessments to comprehensively identify and prioritize hazardous locations. The findings offer practical guidance for policymakers and urban planners to implement targeted, cost-effective safety interventions where resources are scarce. This approach supports the principles of the Safe System framework and can significantly contribute to reducing road traffic injuries and fatalities in low- and middle-income countries.

Keywords

road safety / crash data analysis / road safety assessments

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