CMF / CRF Details
CMF ID: 10029
Change from 5-section "doghouse" protected/permissive left turn to flashing red arrow protected/permissive left turn
Description: Converting at left-turn traffic control on at least one approach from a 5-section "doghouse" protective/permissive left turn to a flashing red arrow with supplemental sign.
Prior Condition: 5-Section "Doghouse" Protected/Permissive Left-Turn Control
Category: Intersection traffic control
Study: Evaluating the Safety Impact of Flashing Red Arrow Protected-Permissive Left-Turn Signal Control in Maryland, Rao et al., 2019
| Star Quality Rating: |  [View score details] |
| Rating Points Total: | 100 |
| Crash Modification Factor (CMF) | |
|---|---|
| Value: | 0.63 |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 0.06 |
| Crash Reduction Factor (CRF) | |
|---|---|
| Value: | 37 (This value indicates a decrease in crashes) |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 6 |
| Applicability | |
|---|---|
| Crash Type: | Left turn |
| 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: | All |
| If countermeasure is intersection-based | |
| Intersection Type: | Roadway/roadway (not interchange related) |
| Intersection Geometry: | 3-leg,4-leg |
| Traffic Control: | Signalized |
| Major Road Traffic Volume: | Minimum of 12586 to Maximum of 42750 Annual Average Daily Traffic (AADT) |
| Minor Road Traffic Volume: | Minimum of 371 to Maximum of 21439 Annual Average Daily Traffic (AADT) |
| Average Major Road Volume : | 26183 Annual Average Daily Traffic (AADT) |
| Average Minor Road Volume : | 7995 Annual Average Daily Traffic (AADT) |
| Development Details | |
|---|---|
| Date Range of Data Used: | 2001 to 2017 |
| Municipality: | |
| State: | MD |
| Country: | United States |
| Type of Methodology Used: | Before/after using empirical Bayes or full Bayes |
| Sample Size (sites): | 23 sites before, 23 sites after |
| Sample Size (site-years): | 70 site-years before, 103 site-years after |
