CMF / CRF Details
CMF ID: 2764
Install offset right turn lane
Description:
Install offset right turn lane to improve sight distance for vehicles on minor road
Prior Condition: No Prior Condition(s)
Category: Intersection geometry
| Crash Modification Factor (CMF) |
|---|
| Value: | 1.02 |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 0.42 |
| Crash Reduction Factor (CRF) |
|---|
| Value: | -2 (This value indicates an increase in crashes) |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 41.8 |
| Applicability |
|---|
| Crash Type: | All |
| Crash Severity: | All |
| Roadway Types: | Principal Arterial Other Freeways and Expressways |
| 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: | Rural |
| 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: | Stop-controlled |
| Major Road Traffic Volume: | Minimum of 10000 to Maximum of 11300 Annual Average Daily Traffic (AADT) |
| Minor Road Traffic Volume: | Minimum of 2305 to Maximum of 2450 Annual Average Daily Traffic (AADT) |
| Average Major Road Volume : | |
| Average Minor Road Volume : | |
| Development Details |
|---|
| Date Range of Data Used: | 2000 to 2005 |
| Municipality: | Muscatine |
| State: | IA |
| Country: | USA |
| Type of Methodology Used: | Simple before/after |
| Sample Size (crashes): | 15 crashes before, 11 crashes after |
| Other Details |
|---|
| Included in Highway Safety Manual? | No |
| Date Added to Clearinghouse: | Mar 21, 2011 |
| Comments: | For 2 approaches. Authors note that the increase in crashes may be attributed to the horizontal curvature of the road near the site and very narrow median width which does not profivde sufficient space for one-stage crossing maneuvers |
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