The impact of existing and "ideal" road design characterisitcs on road safety:the case of Namibia

Abstract

The design of roads plays a significant role in road safety outcomes. Typically, road safety is considered as just one of many considerations in road design and is often not prioritised. The study aimed to assess the relationship between existing and ideal road design and traffic environment, and the frequency of Fatal and Serious Injury (FSI) road crashes in the Namibian context. The assessment (sensitivity analysis) was carried out using developed context-specific Generalised Poisson Crash Prediction Models (GP-CPMs). The results from the sensitivity analysis were concerning, as they indicated that despite the application of standard-compliant design parameters in the crash models, several model covariates demonstrated pronounced combinational effects detrimental to the safety of the road system. The results indicate how important it is to re-assess the relevance of “international” design guidelines, to ensure their relevance in a local road environment and also to the behavioural characteristics of road users.