CMF / CRF Details
CMF ID: 2211
Single-lane exit ramp without taper (right ramp only)
Description: Investigated the effects of freeway exit ramp type on safety in Florida. Parallel to tangent single-lane exit ramp without a taper compared with single-lane exit ramp.
Prior Condition: 1 lane, parallel from tangent ramp with ramp with taper
Category: Interchange design
Study: Impacts of Exit Ramp Type on the Safety Performance of Freeway Diverge Areas, Chen et al., 2008
| Star Quality Rating: |  [View score details] |
| Rating Points Total: | 105 |
| Crash Modification Factor (CMF) | |
|---|---|
| Value: | 1.128 |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 0.1136 |
| Crash Reduction Factor (CRF) | |
|---|---|
| Value: | -12.8 (This value indicates an increase in crashes) |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 11.36 |
| 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: | |
| Minimum Speed Limit: | |
| Maximum Speed Limit: | |
| Speed Unit: | |
| Speed Limit Comment: | |
| Area Type: | |
| Traffic Volume: | |
| Average Traffic Volume: | |
| Time of Day: | All |
| 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: | 2004 to 2006 |
| Municipality: | |
| State: | FL |
| Country: | |
| Type of Methodology Used: | Regression cross-section |
| Sample Size (sites): | 1269 sites |
| Other Details | |
|---|---|
| Included in Highway Safety Manual? | No |
| Date Added to Clearinghouse: | Dec 01, 2009 |
| Comments: | |
