CMF / CRF Details

CMF ID: 3629

Install shoulder rumble strips on roadways with a shoulder width less than 5 feet

Description:

Prior Condition: Roadway with no rumble strips and a shoulder width less than 5 feet

Category: Shoulder treatments

Study: NCHRP Report 641: Guidance for the Design and Application of Shoulder and Centerline Rumble Strips, Torbic et al., 2009

 
Star Quality Rating: 3 Stars   [View score details]
Crash Modification Factor (CMF)
Value: 0.66
Adjusted Standard Error:
Unadjusted Standard Error: 0.1163
Crash Reduction Factor (CRF)
Value: 34   (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error: 11.63
Applicability
Crash Type: Run off road
Crash Severity: K (fatal),A (serious injury),B (minor injury),C (possible injury)
Roadway Types: Principal Arterial Other Freeways and Expressways
Number of Lanes:
Road Division Type: Divided by Median
Speed Limit:
Area Type: Urban
Traffic Volume: Minimum of 11254 to Maximum of 92757 Average Daily Traffic (ADT)
Average Traffic Volume:
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: 1997 to 2006
Municipality:
State: PA
Country: U.S.A.
Type of Methodology Used: Regression cross-section
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Mar-21-2011
Comments: The authors collected data on thru lanes and speed limits but did not provide those data in the report (see p. 50).