The Bicycle and Pedestrian Data Subcommittee of the Transportation Research Board (TRB) hosted a Workshop entitled Factoring Bicycle and Pedestrian Data on Sunday, January 13. Krista Nordback spoke on the topic of estimating Annual Average Daily Bicyclists (AADB) and how long should bicyclists be counted in order to minimize error. The analysis resulted in specific recommendations:
- Install more than 5 permanent bicycle counters per factor group.
- Short-term counts:
Are best collected May through October in northern climates.
Optimal length is 7 days (24 hrs per day), but shorter counts can still be useful.
Her complete presentation may be downloaded below.

how_many_hours_do_i_need_to_count2.pdf |
On Monday, January 14, Dr. Nordback presented on the topic of bicyclist safety at urban intersections and presented the first bicyclist safety performance function for a city in the United States. The analysis shows that individual bicyclist risk of collision with a motorist is substantially lower at intersections with more than 250 bicyclist per day (AADB) passing through the intersection in the study city, Boulder, Colorado. In other words, cyclists are safer in numbers. The presentation can be downloaded below.

bikespfforuscity.pdf |