CMF / CRF Details

CMF ID: 2843

Installation of fixed speed cameras

Description: Installation of fixed speed cameras on arterials limited access freeways

Prior Condition: Ring/beltway highway without speed cameras

Category: Speed management

Study: Effectiveness of speed enforcement through fixed speed cameras: a time series study, Novoa et al., 2009

 
Star Quality Rating: 2 Stars   [View score details]
Rating Points Total: 50
Crash Modification Factor (CMF)
Value: 0.7
Adjusted Standard Error:
Unadjusted Standard Error: 0.0459
Crash Reduction Factor (CRF)
Value: 30   (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error: 4.59
Applicability
Crash Type: All
Crash Severity: All
Roadway Types: Principal Arterial Other Freeways and Expressways
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: 50
Maximum Speed Limit: 50
Speed Unit: mph
Speed Limit Comment: 80 km/h converted to mph
Area Type: Urban
Traffic Volume:
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: 2001 to 2007
Municipality: Barcelona
State:
Country: Spain
Type of Methodology Used: Simple before/after
Sample Size (site-years): 4 site-years before, 4 site-years after
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Mar-21-2011
Comments: Used time series analysis along with poisson regression The number of crashes in the after period were not reported in this study, however, they have been recorded as 300 to give 10 points as a beneift of doubt for one or more of the following: (1) number of miles/sites in the reference/treatment group, (2) number of crashes in the references/treatment group, (3) reporting AADTs for the aggregate dataset but not for the disaggragate dataset used for CMF development.