CMF / CRF Details
CMF ID: 4676
Decrease freeway ramp spacing from infinity to S (ft) with/without auxiliary lane
Description: Decreasing ramp spacing (painted gore to painted gore) on freeway segments from infinity to S (ft) with or without exisiting auxiliary lane
Prior Condition: Ramp spacing approaching infinity, which represents a basic freeway segment with no ramps.
Category: Access management
Study: Safety Evaluation of Geometric Design Criteria for Entrance-Exit Ramp Spacing and Auxiliary Lane Use, Le, T. Q., and Porter, R. J., 2012
Image: View the countermeasure image.
| Star Quality Rating: |  [View score details] |
| Rating Points Total: | 115 |
| Crash Modification Factor (CMF) | |
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| Applicability | |
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| Crash Type: | Multiple vehicle |
| Crash Severity: | All |
| Roadway Types: | Principal Arterial Interstate |
| 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: | |
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| Area Type: | Not specified |
| Traffic Volume: | Minimum of 5,134 to Maximum of 153,500 Average Daily Traffic (ADT) |
| Average Traffic Volume: | 43,158 Average Daily Traffic (ADT) |
| Time of Day: | Not specified |
| If countermeasure is intersection-based | |
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| Development Details | |
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| Date Range of Data Used: | 2006 to 2008 |
| Municipality: | |
| State: | CA,WA |
| Country: | USA |
| Type of Methodology Used: | Regression cross-section |
| Sample Size (site-years): | 1212 site-years |
