January 11, 2007
Vaughan W. Inman
Science Applications International Corporation
Gregory W. Davis
Federal Highway Administration, RD&T
6300 Georgetown Pike
McLean, VA 22101
The primary objective of this paper is to review the key issues in signalization of roundabouts, where the purpose of the signals is to provide pedestrian access, with particular attention to access for persons with severe vision loss. Although roundabouts are infrequently signalized to provide access to pedestrians, roundabouts crosswalks have been signalized where heavy pedestrian flow would otherwise cause long vehicle delays, where unbalanced traffic volumes require metering to create gaps for entering vehicles, and where signals were needed to accommodate rail transit. This report summarizes topic areas that address issues of signalization of roundabouts to provide pedestrian access. These topic areas include:
- Pedestrian crosswalk types.
- Crosswalk location.
- Traffic signals configurations at roundabout pedestrian crossings.
- Crossing requirements of blind pedestrians.
- Accessible pedestrian signals.
- Pedestrian signal warrants.
- The effect of traffic signals on roundabout operations.