CMF / CRF Details

CMF ID: 5188

Change intersection skew angle

Description: Skew angle is defined as the absolute value of the difference between 90 degrees and the actual intersection angle (see illustration).

Prior Condition: No Prior Condition(s)

Category: Intersection geometry

Study: Prediction of the Expected Safety Performance of Rural Two-Lane Highways, Harwood et al., 2000

Image: View the countermeasure image.

Star Quality Rating: Cannot Be Rated (HSM)
Rating Points Total:
Crash Modification Factor (CMF)
Value: Equation
Adjusted Standard Error:
Unadjusted Standard Error:
Crash Reduction Factor (CRF)
Adjusted Standard Error:
Unadjusted Standard Error:
Crash Type: All
Crash Severity: All
Roadway Types: Minor Arterial
Number of Lanes: 2
Road Division Type:
Speed Limit:
Area Type: Rural
Traffic Volume:
Average Traffic Volume:
Time of Day:
If countermeasure is intersection-based
Intersection Type: Roadway/roadway (not interchange related)
Intersection Geometry: 3-leg
Traffic Control: Stop-controlled
Major Road Traffic Volume:
Minor Road Traffic Volume:
Average Major Road Volume :
Average Minor Road Volume :
Development Details
Date Range of Data Used:
Type of Methodology Used:
Other Details
Included in Highway Safety Manual? Yes
Date Added to Clearinghouse: Dec-01-2009
Comments: A related form of this equation is found in the HSM 1st Ed, page 14-17. The HSM form is presented with an assumption that the existing skew angle (base condition) is 90 degrees. The formula has been rearranged for presentation on the CMF Clearinghouse to allow the user to input the existing and proposed skew angles in a single equation.