A variety of research studies have been performed using data from HSIS. Many of the final reports prepared are now available electronically. A complete list of available publications is provided below.
| Title | Pub Date | Author | Report Number |
| Stopping Sight Distance - II | Kay Fitzpatick | ||
| An Attempt to Define the Relationship Between Forces to Crash-Test Vehicles and Occupant Injury in S | Forrest Council et al. | FHWA-RD-95-165 | |
| Zero Tolerance: Four States Experience | John Lacey and Ralph Jones | DOT-HS-809-053 | |
| Study of Accidents at Signalized Intersections Phase I Final Report | ereen J. Wolverton and John J. Monce | ||
| Impacts of access management techniques | Jerome Gluck, Herbert S.Levinson, and Vergil Stover | NCHRP-420 | |
| Safety Effectiveness of Intersection Left-and Right-Turn Lanes | Douglas W. Harwood, Karin M. Bauer, Ingrid B. Potts, Darren J. Torbic, Karen R. Richard, Emilia R. Kohlman Rabbani, Ezra Hauer, Lily Elefteriadou, and Michael S. Griffith | FHWA-RD-02-089 | |
| Study Designs for Passing Sight Distance Requirements: Final Report | Apr-92 | Warren Hughes, Sarath Joshua, and Hugh McGee | FHWA-RD-91-078 |
| Development of Relationship Between Truck Accidents and Geometric Design: Phase 1. Final Report | Aug-93 | S.-P. Miaou, P.S. Hu, T. Wright, S.C. Davis, and A.K. Rathi | |
| Accident Relationships of Roadway Widths on Low-Volume Roads | Jan-94 | Charles V. Zegeer | NCHRP-362 |
| Median Intersection Design | Jan-95 | Douglas W. Harwood | NCHRP-375 |
| Traffic Operations Control for Older Drivers. Final Report | Mar-95 | R. Knoblauch, M. Nitzburg, D. Reinfurt, F. Council, C. Zegeer, and C. Popkin | FHWA-RD-94-119 |
| Development of Severity Indices for Roadside Objects: Resource Materials | Sep-95 | Forrest M. Council and J. Richard Stewart | FHWA-RD-95-165 |
| Capacity and Operational Effects of Mid-Block left Turn Lanes | Jan-97 | James A. Bonneson and Patrick T. McCoy | NCHRP-295 |
| Small Target Visibility | Jan-97 | Doug Mace | |
| An Investigation of Older Driver Freeway Needs and Capabilities | May-97 | R. Knoblauch, M. Nitzburg, and R. Seifert | FHWA-RD-95-194 |
| Safety Effects of Cross-section Design on Rural Multi-lane Highway | May-98 | Jun Wang, Warren E. Hughes, Richard Stewart | FHWA-RD-98-071 |
| Accident Models for Two-Lane Rural Segments and Intersections | Oct-98 | Andrew Vogt and Joe Bared | FHWA-RD-98-133 |
| Prediction of the Expected Safety Performance of Rural Two-Lane Highways | Dec-00 | D. W. Harwood, F. M. Council, E. Hauer, W. E. Hughes, and A. Vogt | FHWA-RD-99-207 |
| Implementation of GIS-Based Highway Safety Analyses | Jan-01 | Richard C. Smith, David L. Harkey, and Bobby Harris | FHWA-RD-01-039 |
| Overview of Current Intersection Safety Conditions: Phase I Result | Nov-01 | D.W. Harwood, D.J. Torbic, K.R. Richard, and Y.R. Mohamedshah |
The safety effects of horizontal curves and grades on rural two-lane highways have been quantified in the American Association of State Highway and Transportation Officials (AASHTO) Highway Safety Manual (HSM), but it was not previously known whether and how the safety performance of horizontal curves and grades interact. Furthermore, there are no established safety effects for crest and sag vertical curves, and it is unknown whether and how the safety performance of crest or sag vertical curves is affected by the presence of horizontal curves.
The objective of this study was to quantify the combined safety effects of horizontal curves and grade combinations and express the results as crash modification factors (CMFs) that can be considered for use in the AASHTO HSM.
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Across the Nation, many agencies have been replacing conventional incandescent light bulbs in traffic signals with light-emitting diodes (LED). LEDs are primarily installed to reduce energy consumption and decrease maintenance. In addition, LEDs are expected to last much longer compared with incandescent bulbs and tend to age gradually. However, a recent study revealed several potential problems with LEDs, including their inability to melt snow and issues related to visual discomfort caused by glare at night.
During late-night flash (LNF) mode (from late night to early morning hours), traffic signals flash yellow for one road (typically, the major road), requiring caution but no stopping, and flash red for the other road (typically, the minor road), requiring drivers to stop and then proceed through the intersection after yielding to the traffic on the major road. The intent of LNF is to reduce energy consumption and delay during periods of low traffic demand. However, in recent years, many agencies have begun replacing LNF with normal phasing operation because of safety concerns.
