CMF / CRF Details
CMF ID: 4911
Install a "Vehicles Entering When Flashing" (VEWF) system (overhead signs at intersection on minor and loops on major)
Description:
Safety effectiveness of "Vehicle Entering When Flashing" (VEWF) intersection conflict warning systems at stop-controlled intersections
Prior Condition: stop-controlled
Category: Signs
Crash Modification Factor (CMF) |
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Value: | 0.95 |
Adjusted Standard Error: | |
Unadjusted Standard Error: | 0.084 |
Crash Reduction Factor (CRF) |
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Value: | 5 (This value indicates a decrease in crashes) |
Adjusted Standard Error: | |
Unadjusted Standard Error: | 8.4 |
Applicability |
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Crash Type: | All |
Crash Severity: | All |
Roadway Types: | Not specified |
Street Type: | |
Minimum Number of Lanes: | 2 |
Maximum Number of Lanes: | 2 |
Number of Lanes Direction: | |
Number of Lanes Comment: | |
Crash Weather: | Not specified |
Road Division Type: | |
Minimum Speed Limit: | 45 |
Maximum Speed Limit: | 55 |
Speed Unit: | mph |
Speed Limit Comment: | |
Area Type: | All |
Traffic Volume: | |
Average Traffic Volume: | |
Time of Day: | |
If countermeasure is intersection-based |
Intersection Type: | Roadway/roadway (not interchange related) |
Intersection Geometry: | 4-leg |
Traffic Control: | Stop-controlled |
Major Road Traffic Volume: | Minimum of 3000 to Maximum of 30000 Annual Average Daily Traffic (AADT) |
Minor Road Traffic Volume: | |
Average Major Road Volume : | |
Average Minor Road Volume : | |
Development Details |
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Date Range of Data Used: | 1996 to 2010 |
Municipality: | |
State: | NC |
Country: | |
Type of Methodology Used: | Before/after using empirical Bayes or full Bayes |
Sample Size (crashes): | 264 crashes after |
Other Details |
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Included in Highway Safety Manual? | No |
Date Added to Clearinghouse: | Aug 01, 2013 |
Comments: | A linear assumption was used to account for changes in traffic volume at the treatment sites (instead of SPFs). |