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Bike ISI Calculator

 

The following documents accompany this Pedestrian and Bicyclist Intersection Safety Indices (ISI) Calculator:

Pedestrian and Bicyclist Intersection Safety Indices: User Guide (Publication No. FHWA-HRT-06-130)
Pedestrian and Bicyclist Intersection Safety Indices: Final Report (Publication No. FHWA-HRT-06-125)

Download Excel Version

Approach 1 Approach 2 Approach 3 Approach 4
 
Name of approach leg
        
MAINADT
 Main Street ADT        
MAINHISPD
 Main street speed limit ≥ 35 mph (1=yes, 0=no)        
TURNVEH
 Presence of turning vehicle traffic across the path of through cyclists (1=yes, 0=no)        
RTLANES
 Number of right turn traffic lanes on main street approach        
BL
 Bike lane present (1=yes, 0=no)        
CROSSADT
 Cross street traffic volume        
SIGNAL
 Traffic signal at intersection (1=yes, 0=no)        
PARKING
 On-street parking on main street approach (1=yes, 0=no)        
RTCROSS
 Number of traffic lanes for cyclists to cross to make a right turn        
CROSSLNS
 Number of through lanes on cross street        
LTCROSS
 Number of traffic lanes for cyclists to cross to make a left turn        

 

Safety Index Through Value =
        
Safety Index Right Turn Value =
        
Safety Index Left Turn Value =
        

The image shows an overhead view of an intersection with crosswalk lines. The left-right street is labeled Main Street and the up-down street is labeled Cross Street. The Main Street approach leg on the right side is labeled as the approach of interest. The point is that 'main' street does not refer to the street with the higher traffic volume, but rather the street that on which the approach leg of interest lies.

 
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