CMF / CRF Details

CMF ID: 10456

Increase speed limit from 55 mph to 60 mph

Description:

Prior Condition:  Posted speed limit of 55 mph

Category: Speed management

Study: Speed Limit Change (55 mph to 60 mph) Safety Evaluation, Saleem et al., 2020

 
Star Quality Rating:4 Stars  [View score details]
Rating Points Total:130
Crash Modification Factor (CMF)
Value:1.039
Adjusted Standard Error:
Unadjusted Standard Error:0.047
Crash Reduction Factor (CRF)
Value:-3.9  (This value indicates an increase in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:4.7
Applicability
Crash Type:Run off road
Crash Severity:All
Roadway Types:All
Street Type:
Minimum Number of Lanes:2
Maximum Number of Lanes:2
Number of Lanes Direction:
Number of Lanes Comment:
Crash Weather:Not specified
Road Division Type:Undivided
Minimum Speed Limit:60
Maximum Speed Limit:60
Speed Unit:mph
Speed Limit Comment:
Area Type:Rural
Traffic Volume:
Average Traffic Volume:2348 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:2012 to 2018
Municipality:
State:MN
Country:
Type of Methodology Used:Before/after using empirical Bayes or full Bayes
Sample Size (crashes):588 crashes after
Sample Size (sites):5739 sites before, 5739 sites after
Sample Size (miles):1909.11 miles before, 1909.11 miles after
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Aug 14, 2020
Comments: