The purpose of this document is to help Federal, State, Tribal, and local (such as municipal and county) agencies understand the benefits of utilizing the Interactive Highway Safety Design Model (IHSDM) during the RSA process. IHSDM is a tool that can aid RSA teams in estimating the safety and performance of an existing or proposed highway against design guidelines.

This document describes three RSAs that were conducted utilizing IHSDM during the RSA process. The FHWA Office of Safety sponsored these three RSAs.