CMF / CRF Details
CMF ID: 8490
Change in pavement roughness
Description: Effects of change in pavement roughness, often measured by International Roughness Index (IRI), on crashes
Prior Condition: International Roughness Index (IRI)=1.5m/km
Category: Roadway
Study: Investigation of the effect of pavement roughness on crash rates for rigid pavement, Elghriany et al., 2016
| Star Quality Rating: |  [View score details] |
| Rating Points Total: | 80 |
| Crash Modification Factor (CMF) | |
|---|---|
| Value: | 4.487 |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | |
| Crash Reduction Factor (CRF) | |
|---|---|
| Value: | -348.7 (This value indicates an increase in crashes) |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | |
| Applicability | |
|---|---|
| Crash Type: | All |
| Crash Severity: | All |
| Roadway Types: | Principal Arterial Interstate |
| 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: | Divided by Median |
| Minimum Speed Limit: | 60 |
| Maximum Speed Limit: | 65 |
| Speed Unit: | mph |
| Speed Limit Comment: | |
| Area Type: | Not specified |
| Traffic Volume: | |
| Average Traffic Volume: | |
| Time of Day: | |
| 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: | 2001 to 2012 |
| Municipality: | |
| State: | OH |
| Country: | USA |
| Type of Methodology Used: | Regression cross-section |
| Other Details | |
|---|---|
| Included in Highway Safety Manual? | No |
| Date Added to Clearinghouse: | Apr 10, 2017 |
| Comments: | Increase IRI from 1.5m/km to 2.5m/km. |
