ITE Journal - May 2020 - 49

Acknowledgements
The author appreciates helpful comments from colleagues on early
versions of the tables and support from the NCDOT administration. The author also appreciates the engineers in North Carolina
and elsewhere who put their careers and reputations on the line
to get alternative designs built so that we might be able to develop
CMFs from them. The views and opinions in this paper are the
author's and do not necessarily represent the views, opinions,
policies, or practices of the NCDOT.

References
1.	 FHWA, "Crash Modification Factor Clearinghouse" website, accessed
December 30, 2019, http://www.cmfclearinghouse.org/.
2.	 Lovell, J. and E. Hauer, "The Safety Effect of Conversion to All-Way Stop
Control," Transportation Research Record 1068, 1986, pp. 103-107.
3.	 Simpson, C.L. and J.E. Hummer, "Evaluation of the Conversion from TwoWay Stop Sign Control to All-Way Stop Sign Control at 53 Locations in
North Carolina." Journal of Transportation Safety and Security, Vol. 2, No. 3,
2010, pp. 239-260.
4.	 Pernia, J.C., J.J. Lu, M.X. Weng, X. Xie, and Z. Yu, "Development of Models
to Quantify the Impacts of Signalization on Intersection Crashes," Florida
DOT, 2002.
5.	 McGee, H., S. Taori, and B.N. Persaud, "NCHRP Report 491: Crash Experience
Warrant for Traffic Signals," Transportation Research Board, 2003.
6.	 Davis, G.A. and N. Aul, "Safety Effects of Left-Turn Phasing Schemes at HighSpeed Intersections," Minnesota DOT, Report No. MN/RC-2007-03, 2007.
7.	 Srinivasan, R., B. Lan, and D. Carter, "Safety Evaluation of Signal Installation
With and Without Left Turn Lanes on Two Lane Roads in Rural and
Suburban Areas," Report No. FHWA/NC/2013-11, NCDOT, October 2014.
8.	 Wang, J.H. and M.A. Abdel-Aty, "Comparison of Safety Evaluation
Approaches for Intersection Signalization in Florida," Presented at the
93rd Annual Meeting of the Transportation Research Board, Paper No.
14-0374, Washington, DC, 2014.
9.	 Sacchia, E., T. Sayed, and K. El-Basyouny, "A Full Bayes Before-After Study Accounting for Temporal and Spatial Effects: Evaluating the Safety Impact of New
Signal Installations," Accident Analysis and Prevention, Vol. 94, 2016, pp. 52-58.
10.	 Persaud, B. N., R.A. Retting, P.E. Garder, and D. Lord, "Observational BeforeAfter Study of the Safety Effect of U.S. Roundabout Conversions Using the
Empirical Bayes Method," Transportation Research Record 1751, 2001.
11.	 Rodegerdts, L. A., M. Blogg, E. Wemple, E. Myers, M. Kyte, M. Dixon, G. List,
A. Flannery, R. Troutbeck, W. Brilon, N. Wu, B. Persaud, C. Lyon, D. Harkey,
and D. Carter, "NCHRP Report 572: Applying Roundabouts in the United
States," Transportation Research Board, 2007.
12.	 Qin, X., A. Bill, M. Chitturi, and D. Noyce, "Evaluation of Roundabout
Safety," Presented at the Transportation Research Board 92nd Annual
Meeting, Paper No. 13-2060, Washington, DC, 2013.
13.	 Abdel-Aty, M.A., C. Lee, J. Park, J.Wang, M. Abuzwidah, and S. Al-Arifi,
"Validation and Application of Highway Safety Manual (Part D) in Florida,"
Florida DOT, May 2014.

14.	 Hummer, J. E., R.L. Haley, S.E. Ott, R.S. Foyle, and C.M. Cunningham,
"Superstreet Benefits and Capacities," Report No. FHWA/NC/2009-06,
NCDOT, 2010.
15.	 Inman, V.W. and R.P. Haas, "Field Evaluation of a Restricted Crossing U-Turn
Intersection," Report No. FHWA-HRT-11-067, 2012.
16.	 Edara, P., C. Sun, and S. Breslow, "Evaluation of J-turn Intersection Design
Performance in Missouri," Missouri DOT, December 2013.
17.	 Gross, F., C. Lyon, B. Persaud, and R. Srinivasan, "Safety Effectiveness of
Converting Signalized Intersections to Roundabouts," Presented at the
91st Annual Meeting of the Transportation Research Board, Paper No.
12-1658, Washington, DC, 2012.
18.	 Zhao, Y., J. Andrey, and P. Deadman, "Whether Conversion and Weather
Matter to Roundabout Safety," Accident Analysis and Prevention, Vol.
66, 2018, pp. 151-159.
19.	 Hummer, J.E., and S. Rao, "Safety Evaluation of a Signalized Restricted
Crossing U-Turn," Report No. FHWA-HRT-17-082, December 2017.
20.	 Reid, J., L. Sutherland, B. Ray, A. Daleiden, P. Jenior, and J. Knudsen, "Median
U-Turn Informational Guide," Report No. FHWA-SA-14-069, August 2014.
21.	 Zlatkovic, M., "Development of Performance Matrices for Evaluating
Innovative Intersections and Interchanges," Report No. UT-15.13, Utah
DOT, September 2015.
22.	 FHWA, "CAP-X: Capacity Analysis for Planning of Junctions," FHWASA-18-067, Version 3.0, October 2018.
23.	 Rodegerdts, L., J. Bansen, C. Tiesler, J. Knudsen, E. Myers, M. Johnson, M.
Moule, B. Persaud, C. Lyon, S. Hallmark, H. Isebrands, R.B. Crown, B. Guichet,
and A. O'Brien, "NCHRP Report 672: Roundabouts: An Informational Guide,
Second Edition," Transportation Research Board, 2010.
24.	 Hummer, J., B. Ray, A. Daleiden, P. Jenior, and J. Knudsen, "Restricted
Crossing U-turn Informational Guide," Report No. FHWA-SA-14-070,
August 2014.
25.	 Warchol, S., N. Rouphail, C. Vaughan, and B. Kerns, "Guidelines for
Signalization of Intersections with Two or Three Approaches," Report No.
NCDOT/NC/2017-11, NCDOT, December 2017.
26.	 Lee, T., T. Chase, C. Cunningham, and S. Warchol, "Movement-Based Safety
Performance Functions for Signalized Intersections," Presented at 99th
Annual Meeting, Transportation Research Board, Washington, DC, 2020.

Joseph E. Hummer, P.E., Ph.D. (M) is the state traffic
management engineer with the North Carolina
Department of Transportation Mobility and Safety
Division. He specializes in alternative intersection and
interchange designs. Joe began researching the designs
in 1990, has published numerous articles about them, and has
invented several new designs. His two-part series in the ITE Journal
in 1998 helped create momentum in this area. He has a bachelor of
science and a master of science in civil engineering from Michigan
State University and a Ph.D. in civil engineering from Purdue
University. Joe is currently vice president of the North Carolina
Section of ITE.
w w w .i t e.or g

May 2020

49
http://www.cmfclearinghouse.org/ http://www.ite.org
ITE Journal - May 2020

Table of Contents for the Digital Edition of ITE Journal - May 2020
