Before and After Study of Safety Improvement Projects on State Highways Funded Through the Highway Safety Improvement Program

Hurwitz, David; Jashami, Hisham; Maharjan, Timila

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Before and After Study of Safety Improvement Projects on State Highways Funded Through the Highway Safety Improvement Program

2026-08-01
By Hurwitz, David ; Jashami, Hisham ; Maharjan, Timila

File Language:

English

Details

Creators:

Hurwitz, David ; Jashami, Hisham ; Maharjan, Timila
Corporate Creators:

Oregon State University. School of Civil and Construction Engineering
Corporate Contributors:

Oregon. Department of Transportation. Research Section ; United States. Department of Transportation. Federal Highway Administration
Subject/TRT Terms:

Before And After Studies Crash Modification Factors Data Analysis Flashing Beacons Four-way Stop Control Highway Safety Rectangular Rapid Flashing Beacon Road Improvements Road Shoulders Rumble Strips Shoulder Rumble Strip State Highways Stopping Two-way Stop Control
Publication/ Report Number:

FHWA-PL-27-01 ; 31896
Resource Type:

Tech Report
Geographical Coverage:

United States ; Iowa
Edition:

Final Report
Corporate Publisher:

Arizona. Dept. of Transportation. Research Center
Abstract:

This study develops a transferable framework for the analysis of three low-cost safety improvement projects installed on state highways in Oregon; specifically Rectangular Rapid Flashing Beacon (RRFB), Shoulder Rumble Strips (SRS), and Two-Way to Four-Way Stop Conversion. A before-after EB study was performed for RRFB and SRS. A cross-sectional analysis was conducted for stop control conversion in the absence of installation data. For RRFB, the Crash Modification Factor (CMF) for total pedestrian crashes was found to be 0.481. The total crashes and rear-end crashes were also found to have reduced by 27% and 14%, respectively. The CMF for total crashes and run-off-road crashes in the presence of SRS was found to be 0.72 and 0.73, respectively. The result from the cross-sectional analysis suggested that four-way stops are associated with approximately a 15.7% reduction in crashes compared to two-way stops.
Format:

PDF
Collection(s):

US Transportation Collection
Main Document Checksum:

urn:sha-512:a4712ca2baa2b9524149cc460ba68635695d8c2d110b24c75ca1652078339ed3313679e366cfa55f047bb1db56cf05c824a05850e3d50ffef4476a1d98aed77b
Download URL:

https://rosap.ntl.bts.gov/view/dot/93142/dot_93142_DS1.pdf
File Type:

[PDF - 5.10 MB ]

File Language:

English

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