Study Details

Study Title: Safety Evaluation of Centerline Plus Shoulder Rumble Strips

Authors: Persaud et al.

Publication Date: JAN, 2015

Abstract: The combined application of centerline and shoulder rumble strips was selected for evaluation under the Federal Highway Administration (FHWA) Evaluation of Low-Cost Safety Improvements Pooled Fund Study. This strategy is intended to reduce the frequency of crashes by alerting drivers that they are about to leave the travelled lane. To date, this combination treatment has not been rigorously evaluated with a multi-state database. Geometric, traffic, and crash data were obtained at treated two-lane rural road locations in Kentucky, Missouri, and Pennsylvania. To account for potential selection bias and regression-to-the-mean, an Empirical Bayes (EB) before-after analysis was conducted, utilizing reference groups of untreated two-lane rural roads with similar characteristics to the treated sites. The analysis also controlled for changes in traffic volumes and time trends in crash counts unrelated to the treatment. The combined results for all states indicate statistically significant crash reductions for all crash types analyzed. The crash type with the smallest crash modification factor (CMF) (i.e., the greatest crash reduction) is head-on with a CMF of 0.632. Run-off-road and sideswipe-opposite-direction crashes have estimated CMFs of 0.742 and 0.767, respectively. For run-off-road, head-on and sideswipe-opposite direction crashes combined (i.e., lane departure crashes), the estimated CMF is 0.733. For all crash types combined, CMFs of 0.800 for all severities and 0.771 for fatal+injury were estimated. Benefit-cost (B/C) ratios were estimated to range from 28.2 to 67.7, depending on the treatment cost and service life assumption, which varied by state.

Study Citation: Lyon, Craig; Bhagwant Persaud; and Kimberly Eccles. "Safety Evaluation of Centerline Plus Shoulder Rumble Strips." Federal Highway Administration, Report FHWA-HRT-15-048 (June 2015).

Related Citations: 1) Persaud, B., C. Lyon, K. Eccles, and J. Soika. "Safety Evaluation of Centerline Plus Shoulder Rumble Strips". Presented at the 94th Annual Meeting of the Transportation Research Board, Paper No. 15-4996, Washington, D.C. (2015). 2) Persaud, B., C. Lyon, K. Eccles, and J. Soika. "Safety Effectiveness of Centerline Plus Shoulder Rumble Strips on Two-Lane Rural Roads". Journal of Transportation Engineering, Vol. 142, No. 5, (2016).

Study Report: Download the Study Report Document


CMFs Associated With This Study

Category: Roadway

Countermeasure: Install centerline and shoulder rumble strips

CMF CRF(%) Quality Crash Type Crash Severity Roadway Type Area Type
0.8 20 5 Stars All All Not specified Rural
0.771 22.9 5 Stars All K,A,B,C Not specified Rural
0.742 25.8 5 Stars Run off road All Not specified Rural
0.632 36.8 5 Stars Head on All Not specified Rural
0.767 23.3 5 Stars Sideswipe All Not specified Rural
0.842 15.8 4 Stars All All Not specified Rural
0.812 18.8 4 Stars All K,A,B,C Not specified Rural
0.613 38.7 4 Stars Run off road All Not specified Rural
0.48 52 3 Stars Head on All Not specified Rural
0.891 10.9 3 Stars Sideswipe All Not specified Rural
0.653 34.7 4 Stars All All Not specified Rural
0.558 44.2 4 Stars All K,A,B,C Not specified Rural
0.758 24.2 4 Stars Run off road All Not specified Rural
0.506 49.4 4 Stars Head on All Not specified Rural
0.628 37.2 4 Stars Sideswipe All Not specified Rural
0.975 2.5 4 Stars All All Not specified Rural
1.019 -1.9 4 Stars All K,A,B,C Not specified Rural
0.92 8 4 Stars Run off road All Not specified Rural
1.021 -2.1 3 Stars Head on All Not specified Rural
0.907 9.3 3 Stars Sideswipe All Not specified Rural
0.851 14.9 5 Stars Run off road All Not specified Rural
0.702 29.8 5 Stars Run off road All Not specified Rural
0.679 32.1 3 Stars Head on,Sideswipe All Not specified Rural
0.817 18.3 3 Stars Head on,Sideswipe All Not specified Rural