CMF / CRF Details
CMF ID: 5457
Convert an open median to a directional median
Description: Convert a full median opening to a directional median opening
Prior Condition: Roadway with full median openings
Category: Access management
Study: Safety Effects of Median Treatments Using Longitudinal Channelizers: Empirical Bayesian Before-and-After Study, Zhou et al., 2013
| Star Quality Rating: |  [View score details] |
| Rating Points Total: | 85 |
| Crash Modification Factor (CMF) | |
|---|---|
| Value: | 0.93 |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 0.1095 |
| Crash Reduction Factor (CRF) | |
|---|---|
| Value: | 7 (This value indicates a decrease in crashes) |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 10.95 |
| Applicability | |
|---|---|
| Crash Type: | All |
| Crash Severity: | All |
| Roadway Types: | Principal Arterial Other |
| Street Type: | |
| Minimum Number of Lanes: | 4 |
| Maximum Number of Lanes: | 6 |
| Number of Lanes Direction: | |
| Number of Lanes Comment: | |
| Crash Weather: | Not specified |
| Road Division Type: | Divided by Median |
| Minimum Speed Limit: | 40 |
| Maximum Speed Limit: | 55 |
| Speed Unit: | mph |
| Speed Limit Comment: | |
| Area Type: | Urban and suburban |
| Traffic Volume: | Minimum of 27000 to Maximum of 96000 Annual Average Daily Traffic (AADT) |
| 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 | |
|---|---|
| Date Range of Data Used: | 2003 to 2010 |
| Municipality: | Tampa |
| State: | FL |
| Country: | |
| Type of Methodology Used: | Before/after using empirical Bayes or full Bayes |
| Sample Size (crashes): | 1159 crashes before, 463 crashes after |
