CMF / CRF Details
CMF ID: 6670
Install shoulder rumble strips and widen shoulder
Description:
Install shoulder rumble strips in combination with widening existing shoulder.
Prior Condition: Original shoulder width 4-6 ft
Category: Shoulder treatments
| Crash Modification Factor (CMF) |
|---|
| Value: | 0.451 |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 0.109 |
| Crash Reduction Factor (CRF) |
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| Value: | 54.9 (This value indicates a decrease in crashes) |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 10.9 |
| Applicability |
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| Crash Type: | All |
| Crash Severity: | K (fatal),A (serious injury),B (minor injury),C (possible injury) |
| Roadway Types: | Not specified |
| Street Type: | |
| Minimum Number of Lanes: | 3 |
| Maximum Number of Lanes: | |
| Number of Lanes Direction: | Both Directions |
| Number of Lanes Comment: | Multi Lane |
| Crash Weather: | Not specified |
| Road Division Type: | |
| Minimum Speed Limit: | |
| Maximum Speed Limit: | |
| Speed Unit: | |
| Speed Limit Comment: | |
| Area Type: | Rural |
| Traffic Volume: | Minimum of 2000 to Maximum of 50000 Annual Average Daily Traffic (AADT) |
| Average Traffic Volume: | |
| Time of Day: | |
| 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 |
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| Date Range of Data Used: | 2003 to 2012 |
| Municipality: | |
| State: | FL |
| Country: | |
| Type of Methodology Used: | Other before/after |
| Sample Size (sites): | 75 sites before |
| Other Details |
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| Included in Highway Safety Manual? | No |
| Date Added to Clearinghouse: | Jun 22, 2015 |
| Comments: | Before condition shoulder width between 4-6 ft. Study method was either EB or CG, the authors chose the method that had the lowest SE. 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. |
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