Click the link to download the IHSDM 2021 software release (version 17.0.0; September 2021).
The IHSDM—which supports the Federal Highway Administration's Data-Driven Safety Analysis initiative—includes five evaluation modules (i.e., Crash Prediction, Design Consistency, Policy Review, Traffic Analysis, and Driver/Vehicle), as well as an Economic Analyses Tool.
To the extent possible, the Crash Prediction Module (CPM) includes a faithful implementation of Part C (Predictive Method) of the American Association of State Highway Transportation Officials' 1st Edition Highway Safety Manual (HSM) for evaluating rural two-lane highways, rural multilane highways, and urban/suburban arterials, as well as HSM 2014 Supplement materials on freeway segments and freeway ramps/interchanges, and prediction methods for roundabouts and six-or-more lane and one-way urban/suburban arterials (developed under NCHRP Project 17-70 and NCHRP Project 17-58, respectively, and intended for inclusion in the future 2nd Edition HSM (HSM2)).
IHSDM 2021 enhancements include new crash prediction models for the following intersection types, which were developed under NCHRP project 17-68 (Intersection Crash Prediction Methods for the Highway Safety Manual) for inclusion in the future HSM2:
• Rural and urban all-way stop-controlled intersections.
• Rural and urban three-leg intersections where the through movement makes a turning maneuver at the intersection.
• Rural three-leg intersections with signal control, for both two-lane and multilane highways.
• Intersections on high-speed urban and suburban arterials (i.e., roadways with speed limits greater than or equal to 50 mph).
• Urban five-leg intersections with signal control.
• Crossroad ramp terminals at single-point diamond interchanges.
• Crossroad ramp terminals at tight diamond interchanges.
Downloading and Installing IHSDM
Frequently Asked Questions
Highway Data/Sample Projects
Resources (Technical Support, Training, and More)