Calibrating Infrastructure Risk Rating (IRR) for Victorian Roads

IRR, developed in New Zealand, is a simplified-risk based road assessment methodology, based on fewer features than other road risk tools – requiring the input of only ten key road variables. Although early days, IRR seems to perform as well as more complicated, proprietary, road risk tools.
Safe System Solutions Pty Ltd is undertaking a project that involves calibrating New Zealand’s IRR by correlating the IRR rating for Victorian roads against real world crashes so as to understand and quantify the strength of the relationship between crash rates and risk as assessed by IRR.