CMF / CRF Details
CMF ID: 4073
Replace Incandescent Traffic Signal Bulbs with Light Emitting Diodes (LEDs)
Description: At urban signalized intersections, incandescent traffic signal bulbs are replaced by light emitting diodes (LEDs) to improve signal visibility
Prior Condition: All signal heads at a 4-legged intersection had incandescent traffic signal bulbs
Category: Intersection traffic control
Study: LED traffic signal retrofits: Implications for intersection safety, N. Jami, S. Ivey, M. Lipinski, M.M. Golias, 2012
| Star Quality Rating: |  [View score details] |
| Rating Points Total: | 105 |
| Crash Modification Factor (CMF) | |
|---|---|
| Value: | 1.47 |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 0.042 |
| Crash Reduction Factor (CRF) | |
|---|---|
| Value: | -47 (This value indicates an increase in crashes) |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 4.2 |
| Applicability | |
|---|---|
| Crash Type: | All |
| Crash Severity: | All |
| 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: | Urban |
| Traffic Volume: | |
| Average Traffic Volume: | |
| Time of Day: | All |
| If countermeasure is intersection-based | |
| Intersection Type: | Roadway/roadway (not interchange related) |
| Intersection Geometry: | 4-leg |
| Traffic Control: | Signalized |
| Major Road Traffic Volume: | Minimum of 14681 to Maximum of 68433 Annual Average Daily Traffic (AADT) |
| Minor Road Traffic Volume: | Minimum of 2843 to Maximum of 33412 Annual Average Daily Traffic (AADT) |
| Average Major Road Volume : | 32926 Annual Average Daily Traffic (AADT) |
| Average Minor Road Volume : | 16914 Annual Average Daily Traffic (AADT) |
| Development Details | |
|---|---|
| Date Range of Data Used: | 2000 to 2008 |
| Municipality: | Memphis |
| State: | TN |
| Country: | USA |
| Type of Methodology Used: | Before/after using empirical Bayes or full Bayes |
| Sample Size (crashes): | 1180 crashes before, 1229 crashes after |
| Other Details | |
|---|---|
| Included in Highway Safety Manual? | No |
| Date Added to Clearinghouse: | Nov 01, 2012 |
| Comments: | |
