CMF / CRF Details
CMF ID: 10246
Change right-turn lane geometry to increase line of sight (approach level)
Description: Changes made to study approaches include: sharpening the flat approach angle typical in the traditional design, reducing the radius, adjusting the stop/yield bar position, and/or modifying the corner island to improve safety by increasing the line of sight of approaching through traffic.
Prior Condition: Conventional right turn channel.
Category: Intersection geometry
Study: Safety Effect of Smart Right-Turn Design at Intersections, Barua, U., 2018
| Star Quality Rating: |  [View score details] |
| Rating Points Total: | 65 |
| Crash Modification Factor (CMF) | |
|---|---|
| Value: | 0.53 |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | |
| Crash Reduction Factor (CRF) | |
|---|---|
| Value: | 47 (This value indicates a decrease in crashes) |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | |
| Applicability | |
|---|---|
| Crash Type: | Right turn |
| Crash Severity: | All |
| Roadway Types: | Principal Arterial Other |
| Street Type: | |
| Minimum Number of Lanes: | |
| Maximum Number of Lanes: | |
| 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: | All |
| If countermeasure is intersection-based | |
| Intersection Type: | Roadway/roadway (not interchange related) |
| Intersection Geometry: | 4-leg |
| Traffic Control: | Signalized |
| Major Road Traffic Volume: | |
| Minor Road Traffic Volume: | |
| Average Major Road Volume : | |
| Average Minor Road Volume : | |
| Development Details | |
|---|---|
| Date Range of Data Used: | 2011 to 2018 |
| Municipality: | Austin |
| State: | TX |
| Country: | |
| Type of Methodology Used: | Before/after using empirical Bayes or full Bayes |
| Sample Size (crashes): | 54 crashes before, 3 crashes after |
| Sample Size (sites): | 1 sites before, 1 sites after |
| Sample Size (site-years): | 6 site-years before, 1 site-years after |
| Other Details | |
|---|---|
| Included in Highway Safety Manual? | No |
| Date Added to Clearinghouse: | Dec 07, 2019 |
| Comments: | |
