iRAP Methodology fact sheets

The iRAP Methodology fact sheets answer many of the questions people have about the iRAP approach, covering topics such as crash types, Star Rating Score equations, model calibration, and estimation of economic benefits and costs. These fact sheets complement the Road Attribute Risk Factor fact sheets.

The ‘iRAP Methodology’ fact sheets describe the Star Rating and Safer Roads Investment Plan methodologies, while the ‘iRAP Road Attribute Risk Factors’ fact sheets describe the risk factors used in the models.