CMF / CRF Details
CMF ID: 9108
Provide passing lane or climbing lane
Description:
Provide passing lane or climbing lane
Prior Condition: Rural, 2-lane roads without passing lanes.
Category: Roadway
| Crash Modification Factor (CMF) |
|---|
| Value: | 0.68 |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 0.08 |
| Crash Reduction Factor (CRF) |
|---|
| Value: | 32 (This value indicates a decrease in crashes) |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 8 |
| Applicability |
|---|
| Crash Type: | All |
| Crash Severity: | All |
| Roadway Types: | Not specified |
| Street Type: | |
| Minimum Number of Lanes: | 2 |
| Maximum Number of Lanes: | 2 |
| Number of Lanes Direction: | |
| Number of Lanes Comment: | |
| Crash Weather: | Not specified |
| Road Division Type: | Undivided |
| 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: | |
| 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: | 1997 to 2013 |
| Municipality: | |
| State: | WY |
| Country: | USA |
| Type of Methodology Used: | Before/after using empirical Bayes or full Bayes |
| Sample Size (sites): | 4 sites before, 4 sites after |
| Sample Size (site-years): | 32 site-years before, 28 site-years after |
| Sample Size (miles): | 26 miles before, 26 miles after |
| Sample Size (miles): | 208 mile-years before, 182 mile-years after |
| Other Details |
|---|
| Included in Highway Safety Manual? | No |
| Date Added to Clearinghouse: | Jan 17, 2018 |
| Comments: | Applies to entire corridor with and without added passing lanes. Excluding crashes related to animals, intersections and driver impairments. The number of crashes in the after period were not reported in this study, however, they have been recorded as 300 to give 10 points as a beneift of doubt for one or more of the following: (1) number of miles/sites in the reference/treatment group, (2) number of crashes in the references/treatment group, (3) reporting AADTs for the aggregate dataset but not for the disaggragate dataset used for CMF development. |
[View score details]