Evaluation of Road Safety Audit Implementation Using Crash Reduction Factor and HDM-4

Road Safety Audit (RSA) is a formal and independent safety performance review of road transportation projects by an experienced team of safety specialists to address safety. Noida–Greater Noida (NGN) Expressway is aneight-lane divided carriageway connecting Noida and Greater Noida. This Expressway has witnessed high crash rates and therefore, a comprehensive RSA was conducted and suggestions for improving safety on this expressway were recommended. These included replacement of concrete guard post on median by double row metal beam crash barrier, redevelopment of entry and exit points as per Indian Standards, marking and road studs on each of the traffic lanes and particularly near exit/entry points of auxiliary lanes. The Speed Enforcement Cameras and Close Circuit TV with Variable Message Signs were also installed at every 2 km. As the RSA recommendations were implemented in the year 2013 by the concerned stakeholders, an analysis was carried out to understand whether the measures had contributed towards the reduction in road crashes if any in the subsequent years 2014, 2015 and 2016. It was evident from this analysis that the total crashes after RSA had exhibited 84% reduction coupled with 91% reduction in fatal crashes. The analysis further revealed that the average speed of all types of vehicle had marginally increased after implementation of RSA recommendations, despite an annual increase in traffic in addition to crash reduction. The paper culminates with the analysis of the crash data to arrive at crash reduction factor followed by the use of HDM-IV wherein the economic benefits derived based on crash reduction was deduced.