CMF / CRF Details
Install Box Span Signal
Countermeasure ID: 8723
Description:
Prior Condition: Intersections with diagonal span signal configurations
Category: Advanced technology and ITS
Study: Safety Evaluation of Box Span Signal Configuration, Yassin et al., 2017
| Star Quality Rating: |  [View score details] | 
| Rating Points Total: | 110 | 
| Crash Modification Factor (CMF) | |
|---|---|
| Value: | 0.975 | 
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 0.04 | 
| Crash Reduction Factor (CRF) | |
|---|---|
| Value: | 2.5 (This value indicates a decrease in crashes) | 
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 4 | 
| Applicability | |
|---|---|
| Crash Type: | Other | 
| Crash Severity: | All | 
| Roadway Types: | Not specified | 
| Street Type: | |
| Minimum Number of Lanes: | |
| Maximum Number of Lanes: | 4 | 
| Number of Lanes Direction: | |
| Number of Lanes Comment: | < = 4 Lanes | 
| Crash Weather: | Not specified | 
| Road Division Type: | All | 
| 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: | Not specified | 
| Intersection Geometry: | 3-leg,4-leg | 
| Traffic Control: | Signalized | 
| Major Road Traffic Volume: | Minimum of 3220 to Maximum of 66316 Annual Average Daily Traffic (AADT) | 
| Minor Road Traffic Volume: | Minimum of 471 to Maximum of 53080 Annual Average Daily Traffic (AADT) | 
| Average Major Road Volume : | 18476 Annual Average Daily Traffic (AADT) | 
| Average Minor Road Volume : | 7094 Annual Average Daily Traffic (AADT) | 
| Development Details | |
|---|---|
| Date Range of Data Used: | 2006 to 2011 | 
| Municipality: | |
| State: | MI | 
| Country: | USA | 
| Type of Methodology Used: | Before/after using empirical Bayes or full Bayes | 
| Sample Size (crashes): | 1164.8 crashes before, 1064 crashes after | 
| Sample Size (sites): | 117 sites before, 117 sites after | 
| Other Details | |
|---|---|
| Included in Highway Safety Manual? | No | 
| Date Added to Clearinghouse: | Nov 17, 2017 | 
| Comments: | The CMF is for intersection crashes for people at all ages | 

