CMF / CRF Details
CMF ID: 10564
Roundabout geometry
Description: Various geometric elements of roundabout
Prior Condition: No Prior Condition(s)
Category: Intersection geometry
Study: Developing crash modification factors for roundabouts using a cross-sectional method, Al-Marafi et al., 2020
| Star Quality Rating: |  [View score details] |
| Rating Points Total: | 70 |
| Crash Modification Factor (CMF) | |
|---|---|
| Value: |  |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | |
| Crash Reduction Factor (CRF) | |
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| Value: | |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | |
| 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: | |
| 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: | Not specified |
| Traffic Volume: | |
| Average Traffic Volume: | |
| Time of Day: | |
| If countermeasure is intersection-based | |
| Intersection Type: | Roadway/roadway (not interchange related) |
| Intersection Geometry: | No values chosen. |
| Traffic Control: | Roundabout |
| Major Road Traffic Volume: | Minimum of 1288 to Maximum of 16071 Annual Average Daily Traffic (AADT) |
| Minor Road Traffic Volume: | Minimum of 1200 to Maximum of 10002 Annual Average Daily Traffic (AADT) |
| Average Major Road Volume : | 6966 Annual Average Daily Traffic (AADT) |
| Average Minor Road Volume : | 4341 Annual Average Daily Traffic (AADT) |
| Development Details | |
|---|---|
| Date Range of Data Used: | 2010 to 2015 |
| Municipality: | Toowoomba City |
| State: | notusa |
| Country: | Australia |
| Type of Methodology Used: | Regression cross-section |
| Sample Size (sites): | 49 sites |
| Other Details | |
|---|---|
| Included in Highway Safety Manual? | No |
| Date Added to Clearinghouse: | Dec 17, 2020 |
| Comments: | CMFunction for number of entering lanes on the major approach |
