Study Details

Study Title: Crash Reduction Factors for Traffic Engineering and ITS Improvements

Authors: Harkey et al.

Publication Date: 2008

Abstract:

Study Citation: Harkey, D.L., R. Srinivasan, J. Baek, B. Persaud, C. Lyon, F.M. Council, K. Eccles, N. Lefler, F. Gross, E. Hauer, J. Bonneson, "Crash Reduction Factors for Traffic Engineering and ITS Improvements", NCHRP Project 17-25 Final Report, Washington, D.C., National Cooperative Highway Research Program, Transportation Research Board, (2008)


CMFs Associated With This Study

Category: Access management

Countermeasure: 10-ft to 100-ft conversion (median width)

CMF CRF(%) Quality Crash Type Crash Severity Roadway Type Area Type
0.25 75 5 Stars Cross median Not Specified Not specified Rural
0.22 78 5 Stars Cross median Not Specified Not specified Rural
0.36 64 5 Stars Cross median Not Specified Not specified Urban
0.35 65 5 Stars Cross median Not Specified Not specified Urban
0.3 70 5 Stars Cross median Not Specified Not specified Urban

Countermeasure: 10-ft to 20-ft conversion (median width)

CMF CRF(%) Quality Crash Type Crash Severity Roadway Type Area Type
0.86 14 5 Stars Cross median Not Specified Not specified Rural
0.84 16 5 Stars Cross median Not Specified Not specified Rural
0.89 11 5 Stars Cross median Not Specified Not specified Urban
0.89 11 5 Stars Cross median Not Specified Not specified Urban
0.87 13 5 Stars Cross median Not Specified Not specified Urban

Countermeasure: 10-ft to 30-ft conversion (median width)

CMF CRF(%) Quality Crash Type Crash Severity Roadway Type Area Type
0.74 26 5 Stars Cross median Not Specified Not specified Rural
0.71 29 5 Stars Cross median Not Specified Not specified Rural
0.8 20 5 Stars Cross median Not Specified Not specified Urban
0.79 21 5 Stars Cross median Not Specified Not specified Urban
0.76 24 5 Stars Cross median Not Specified Not specified Urban

Countermeasure: 10-ft to 40-ft converstion (median width)

CMF CRF(%) Quality Crash Type Crash Severity Roadway Type Area Type
0.63 37 5 Stars Cross median Not Specified Not specified Rural
0.6 40 5 Stars Cross median Not Specified Not specified Rural
0.71 29 5 Stars Cross median Not Specified Not specified Urban
0.71 29 5 Stars Cross median Not Specified Not specified Urban
0.67 33 5 Stars Cross median Not Specified Not specified Urban

Countermeasure: 10-ft to 50-ft conversion (median width)

CMF CRF(%) Quality Crash Type Crash Severity Roadway Type Area Type
0.54 46 5 Stars Cross median Not Specified Not specified Rural
0.51 49 5 Stars Cross median Not Specified Not specified Rural
0.64 36 5 Stars Cross median Not Specified Not specified Urban
0.63 37 5 Stars Cross median Not Specified Not specified Urban
0.59 41 5 Stars Cross median Not Specified Not specified Urban

Countermeasure: 10-ft to 60-ft conversion (median width)

CMF CRF(%) Quality Crash Type Crash Severity Roadway Type Area Type
0.46 54 5 Stars Cross median Not Specified Not specified Rural
0.43 57 5 Stars Cross median Not Specified Not specified Rural
0.57 43 5 Stars Cross median Not Specified Not specified Urban
0.56 44 5 Stars Cross median Not Specified Not specified Urban
0.51 49 5 Stars Cross median Not Specified Not specified Urban

Countermeasure: 10-ft to 70-ft conversion (median width)

CMF CRF(%) Quality Crash Type Crash Severity Roadway Type Area Type
0.4 60 5 Stars Cross median Not Specified Not specified Rural
0.36 64 5 Stars Cross median Not Specified Not specified Rural
0.51 49 5 Stars Cross median Not Specified Not specified Urban
0.5 50 5 Stars Cross median Not Specified Not specified Urban
0.45 55 5 Stars Cross median Not Specified Not specified Urban

Countermeasure: 10-ft to 80-ft conversion (median width)

CMF CRF(%) Quality Crash Type Crash Severity Roadway Type Area Type
0.34 66 5 Stars Cross median Not Specified Not specified Rural
0.31 69 5 Stars Cross median Not Specified Not specified Rural
0.46 54 5 Stars Cross median Not Specified Not specified Urban
0.45 55 5 Stars Cross median Not Specified Not specified Urban
0.39 61 5 Stars Cross median Not Specified Not specified Urban

Countermeasure: 10-ft to 90-ft conversion (median width)

CMF CRF(%) Quality Crash Type Crash Severity Roadway Type Area Type
0.29 71 5 Stars Cross median Not Specified Not specified Rural
0.26 74 5 Stars Cross median Not Specified Not specified Rural
0.41 59 5 Stars Cross median Not Specified Not specified Urban
0.4 60 5 Stars Cross median Not Specified Not specified Urban
0.34 66 5 Stars Cross median Not Specified Not specified Urban

Category:Roadway

Countermeasure: Increased pavement friction

CMF CRF(%) Quality Crash Type Crash Severity Roadway Type Area Type
0.76 24 5 Stars All All All All
0.43 57 5 Stars Wet road All All All
0.83 17 5 Stars Rear end All All All
0.58 42 4 Stars Rear end All All All
0.7 30 5 Stars Single vehicle All All All

Countermeasure: Road diet (Convert 4-lane undivided road to 2-lanes plus turning lane)

CMF CRF(%) Quality Crash Type Crash Severity Roadway Type Area Type
0.71 [B] 29 5 Stars All All Minor Arterial Urban