CMF / CRF Details
CMF ID: 4234
Decrease inside paved shoulder width from 4ft to 2ft (outside paved shoulder width = 8ft)
Description: Interchange influence area on urban four-lane freeway with a 2-ft inside paved shoulder and a 8-ft outside paved shoulder with warning device.
Prior Condition: 4-ft paved inside shoulder and 8-ft paved outside shoulder within interchange influence area
Category: Shoulder treatments
Study: Developing Crash Modification Factors for Interchange Influence Areas on Urban Four-Lane Freeways Using Multivariate Adaptive Regression Splines, Haleem, Gan, and Lu, 2012
Star Quality Rating: | [View score details] |
Rating Points Total: | 105 |
Crash Modification Factor (CMF) | |
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Value: | 0.749 |
Adjusted Standard Error: | |
Unadjusted Standard Error: | 0.1 |
Crash Reduction Factor (CRF) | |
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Value: | 25.1 (This value indicates a decrease in crashes) |
Adjusted Standard Error: | |
Unadjusted Standard Error: | 10 |
Applicability | |
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Crash Type: | All |
Crash Severity: | All |
Roadway Types: | Principal Arterial Other Freeways and Expressways |
Street Type: | |
Minimum Number of Lanes: | 4 |
Maximum Number of Lanes: | 4 |
Number of Lanes Direction: | |
Number of Lanes Comment: | |
Crash Weather: | Not specified |
Road Division Type: | Divided by Median |
Minimum Speed Limit: | |
Maximum Speed Limit: | |
Speed Unit: | |
Speed Limit Comment: | |
Area Type: | Urban |
Traffic Volume: | |
Average Traffic Volume: | |
Time of Day: | Not specified |
If countermeasure is intersection-based | |
Intersection Type: | |
Intersection Geometry: | |
Traffic Control: | |
Major Road Traffic Volume: | |
Minor Road Traffic Volume: | |
Average Major Road Volume : | |
Average Minor Road Volume : |
Development Details | |
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Date Range of Data Used: | 2005 to 2008 |
Municipality: | |
State: | FL |
Country: | United States |
Type of Methodology Used: | Regression cross-section |
Sample Size (crashes): | 12078 crashes |