CMF / CRF Details
CMF ID: 8334
Install an additional lane
Description: Use reducing lane and shoulder width to install additional lanes for urban freeway
Prior Condition: Freeway with fewer lanes
Category: Roadway
Crash Modification Factor (CMF) |
Value: |
0.76
|
Adjusted Standard Error: |
|
Unadjusted Standard Error: |
0.092 |
Crash Reduction Factor (CRF) |
Value: |
24 (This value indicates a decrease in crashes)
|
Adjusted Standard Error: |
|
Unadjusted Standard Error: |
9.2 |
Applicability |
Crash Type: |
All |
Crash Severity: |
K (fatal),A (serious injury),B (minor injury),C (possible injury) |
Roadway Types: |
Principal Arterial Other Freeways and Expressways |
Number of Lanes: |
2-5 |
Road Division Type: |
Divided by Median |
Speed Limit: |
>50 |
Area Type: |
Urban |
Traffic Volume: |
Minimum of 200 to Maximum of 281450 Average Daily Traffic (ADT)
|
Time of Day: |
All |
If countermeasure is intersection-based |
Intersection Type: |
|
Intersection Geometry: |
|
Traffic Control: |
|
Major Road Traffic Volume: |
|
Minor Road Traffic Volume: |
|
Development Details |
Date Range of Data Used: |
2010 to 2013 |
Municipality: |
Dallas, Houston, San Antonio |
State: |
TX |
Country: |
USA |
Type of Methodology Used: |
Regression cross-section |
Sample Size (crashes): |
407 crashes |
Sample Size (sites): |
536 sites |
Sample Size (site-years): |
2104 site-years |
Other Details |
Included in Highway Safety Manual? |
No |
Date Added to Clearinghouse: |
Jan-17-2017 |
Comments: |
CMF applies to adding one additional lane with 11 ft average lane width |