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FHWA Highway Safety Programs

Road Safety Audit Case Studies: Using IHSDM in the RSA Process

fhwasa14071.pdf (4.85 MB)

Cover: Road Safety Audit Case Studies: Using IHSDM in the RSA Process

July 2014


This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The U.S. Government assumes no liability for the use of the information contained in this document. This report does not constitute a standard, specification, or regulation.

The U.S. Government does not endorse products or manufacturers. Trademarks or manufacturers' names appear in this report only because they are considered essential to the objective of this document.

Technical Documentation Page

1. Report No. FHWA


2. Government Accession No.

3. Recipient's Catalog No.

4. Title and Subtitle

Road Safety Audit Case Studies: Using IHSDM in the RSA Process

5. Report Date

July 2014

6. Performing Organization Code

7. Authors

Dan Nabors, Elissa Goughnour

8. Performing Organization Report No.

9. Performing Organization Name and Address

Vanasse Hangen Brustlin, Inc.
8300 Boone Boulevard, Suite 700
Vienna, VA 22182-2626

10. Work Unit No. (TRAIS)

11. Contract or Grant No.

12. Sponsoring Agency Name and Address

Federal Highway Administration
Office of Safety
1200 New Jersey Ave. S.E.
Washington, DC 20590

13. Type of Report and Period Covered

Final Report, July 2014

14. Sponsoring Agency Code


15. Supplementary Notes:

The Federal highway Administration Office of Safety sponsored the study of the Road Safety Audits reported in this document. The Task Manager for this report was Rebecca Crowe (FHWA Office of Safety). Graphic design was provided by Jorge Quinones.

16. Abstract

Road Safety Audits (RSAs) are a formal safety performance examination of an existing or future roadway or off-road facility and are conducted by an independent, experienced, multidisciplinary team. The purpose of the Road Safety Audit Case Studies: Using IHSDM in the RSA Process is to help Federal, State, Tribal, and local agencies understand the benefits of using the Interactive Highway Safety Design Model (IHSDM) during the RSA process as a decision-support tool to evaluate and estimate the safety and operation of various design features. This case study document provides a review of the RSA process, an overview of IHSDM, and three case study examples of RSAs that utilized IHSDM. The case studies include photographs, a project background, how IHSDM was used, key RSA findings and suggestions, and the benefits of the IHSDM. These case studies will help jurisdictions incorporate this useful decision-support tool into the RSA process.

17. Key Words

Road safety audit, Interactive Highway Safety Design Model, IHSDM, decision-support tool, roadway design

18. Distribution Statement

No restrictions. This document is available to the public through the National Technical Information Service, Springfield, Virginia 22161.

19. Security Classif. (of this report)


20. Security Classif. (of this page)


21. No. of Pages:


22. Price

Form DOT F 1700.7 (8-72) – Reproduction of form and completed page is authorized


Information obtained for this document involved transportation agencies at the Federal, State, and local levels. The Federal Highway Administration (FHWA) and the authors greatly appreciate the cooperation of the Rhode Island Department of Transportation, the Town of Glocester, Rhode Island, Montana Department of Transportation, and the Oregon Department of Transportation.