CMF / CRF Details
CMF ID: 6171
Lower posted speed from 160 km/h to 140 km/h
Description: Reducing the speed limit from 160 km/h to 140 km/h
Prior Condition: Speed Limit 160 km/h
Category: Speed management
Study: A Study of the Safety Impact of Speed Limit Reduction on Abu Dhabi Freeways, Abdelany et al., 2014
| Star Quality Rating: |  [View score details] |
| Rating Points Total: | 110 |
| Crash Modification Factor (CMF) | |
|---|---|
| Value: | 1.066 |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 0.4142 |
| Crash Reduction Factor (CRF) | |
|---|---|
| Value: | -6.6 (This value indicates an increase in crashes) |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 41.42 |
| Applicability | |
|---|---|
| Crash Type: | All |
| Crash Severity: | K (fatal) |
| Roadway Types: | Principal Arterial Other Freeways and Expressways |
| Street Type: | |
| Minimum Number of Lanes: | 4 |
| Maximum Number of Lanes: | 4 |
| Number of Lanes Direction: | |
| Number of Lanes Comment: | |
| Crash Weather: | Not specified |
| Road Division Type: | Divided by Median |
| Minimum Speed Limit: | 160 |
| Maximum Speed Limit: | 160 |
| Speed Unit: | km/h |
| Speed Limit Comment: | |
| Area Type: | Not specified |
| Traffic Volume: | |
| Average Traffic Volume: | 43934 Annual Average Daily Traffic (AADT) |
| Time of Day: | All |
| 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 | |
|---|---|
| Date Range of Data Used: | 2006 to 2011 |
| Municipality: | Abu Dhabi |
| State: | notusa |
| Country: | United Arab Emirates |
| Type of Methodology Used: | Before/after using empirical Bayes or full Bayes |
| Sample Size (sites): | 29 sites before, 29 sites after |
| Sample Size (site-years): | 116 site-years before, 29 site-years after |
| Sample Size (miles): | 99 miles before, 99 miles after |
| Sample Size (miles): | 396 mile-years before, 99 mile-years after |
