This paper was presented at the session titled `Road network screening for identifying and prioritising safety improvements'. The practice of road geometric design is undertaken in a number of phases, commonly named planning and feasibility, preliminary design, detailed design, and construction. Key decisions that affect safety are based on standards, policies and guidelines or in the absence of those, on the best engineering judgement of the practitioners. Today, it is recognised that the professional experience of one individual is not sufficient to ensure road safety. Projects in Ontario, Canada have used multidisciplinary professional teams (traffic engineer, road designer, human factors and safety engineering specialists, among others) in the evaluation of existing roads to determine safety concerns as fundamental imput to future projects (3 or 4R). A formalised process integrating human factors and explicit safety has been developed for identifying sites with potential for safety improvement, for diagnosing problems at these sites and for selecting cost-beneficial countermeasures. Countermeasure recommendations are substantiated by the findings of research studies of safety effects based on collision analyses. (A)
Abstract