Cost-benefit analysis of road safety measures

Road accidents represent one of the most serious problems faced by the Ministries of Public Health in the World.In Italy for example, in the year 2007 there were almost 330, 000 injuries and 5, 131 fatalities; 230, 871 crashes in allwhich resulted in an estimated € 30.4 billion financial loss, corresponding to 2% of GDP. In 1999 the National Road SafetyPlan (NRSP), among other things, funded the requalification of several unsafe road infrastructures at higher risk ofaccidents. Unlike other infrastructure investment plans, NRSP usually requires: i) specific safety analysis of crash historyto identify the critical road; ii) proactive action, e.g. RSAs and RSARs; iii) before-after accident study; iv) ex-postmonitoring of road user behaviors, etc. The paper presents some unsafe roads in urban and suburban areas which wererenovated through NRSP strategies and whose projects were submitted to Road Safety Audit procedure for black spottreatment. It examines the effect of physical traffic calming measures (e.g. roundabouts) on accident risk and userbehaviours: ante- and post-operam evaluations are compared on the basis of accident data and investigations in situ(particularly traffic flow and operating speed). Finally, a profitability analysis of several parameters (e.g. accident socialcosts) is performed. In a region like Sicily, the first Road Administration investments on unsafe infrastructures, partiallyfunded by NPRS, have shown very positive results as to safety and financial aspects.