INTERACTIVE HIGHWAY SAFETY DESIGN MODEL: A BRIEF OVERVIEW

In an attempt to marshal available knowledge about safety into a more useful form for highway planners and designers, the Federal Highway Administration (FHWA) is developing the Interactive Highway Safety Design Model (IHSDM). IHSDM will be a suite of evaluation tools for assessing the safety impacts of geometric design decisions. IHSDM can also be viewed as an analytical tool supporting the road safety audit process. IHSDM's evaluation capabilities will help planners and designers maximize the safety benefits of highway projects within the constraints of cost, context, and other considerations. IHSDM is being designed for evaluation of existing roadways as part of resurfacing, restoration, and rehabilitation and reconstruction projects as well as projects involving new roadways. For ease of use in the design and review phases of project development, IHSDM is being integrated into the computer-aided design environment in which most design work is currently performed. The functionality of IHSDM is organized into five modules, which are described in the paper. The development of IHSDM is a long-term, multiyear activity. Release of the full model for two-lane rural highways is scheduled for 2002. Additional details on the IHSDM development process are also provided.