Under the auspices of the TRANSED 2004 Steering Committee, ECOMO Foundation

 Sunday, May 23, 9:45-12:30

　

Commentator: Dr. Akihiro Mihoshi, Kinki University, Japan

　

Billie Louise Bentzen, COMS, Ph.D. and Janet M. Barlow, COMS, M.Ed.

Boston College, U.S.A.

　

 Research was conducted at two unfamiliar, complex, signalized intersections in each of three U.S. cities to obtain objective data on safety, orientation and independence of pedestrians who are blind as they make crossings. The intersections did not have accessible (audible) signals. Sixteen proficient blind travelers crossed streets at both intersections in each city.

　

 Measures included where participants were standing when they began crossing, where they were headed as they began crossing, where they were when they completed the crossing, when they initiated the crossing (in relation to the signal cycle) and when they completed the crossing (in relation to the signal cycle). Participant requests for assistance with any part of the crossing task, and the occasional need for experimenter intervention for safety were also recorded.

　

 Results demonstrate that pedestrians who are blind have considerable difficulty locating crosswalks, aligning to cross, determining the onset of the walk interval, maintaining a straight crossing path, and completing crossings before the onset of traffic perpendicular to their path of travel.

　

 Pedestrians who are blind or visually impaired often travel in unfamiliar areas and cross at signalized intersections. This research documents safety, orientation and independence of pedestrians who are blind, crossing at unfamiliar, complex, signalized intersections. Data was collected, in three cities, with 16 participants who were unable to see crosswalk lines, pushbutton poles, or pedestrian signals, on the following variables: participants' location in relation to the crosswalk at the beginning of the street crossing; crossing alignment; travel within the crosswalk; location in relation to the crosswalk at the end of the crossing; delay after the onset of the walk interval (or parallel straight-ahead traffic); pedestrian signal status at onset of crossing; vehicular signal status at end of crossing; finding and use of pushbuttons; and requests for assistance or need for intervention for safety at any part in the sequence of crossing tasks. All participants were accustomed to crossing independently at signalized intersections using a long cane or dog guide.

　

 The three cities were Portland, OR, Cambridge, MA, and Charlotte, NC. The six intersections (two in each city) had the following types of geometric and signalization complexity: skewed crosswalk; median; splitter island; right turn lane; more than one left turn lane; offset intersection; leading left turn interval; pedestrian phase on recall; pushbutton actuated pedestrian phase; split phasing; concurrent pedestrian phasing; exclusive pedestrian phasing; mixed exclusive and concurrent pedestrian phasing; and leading pedestrian interval. (See Fig. 1 for two of the intersections used.)

　

　

 Blind participants were tested individually in sessions lasting approximately 1.5 hours during which they traveled two routes at each of two intersections, each route requiring the crossing of two streets. They were accompanied at all times by one of the researchers who communicated instructions for the experimental procedure, and who was responsible for their safety. The other researcher obtained data. Both researchers were Certified Orientation and Mobility Specialists.

　

 Participants used their usual travel aid (long cane or dog guide) and techniques to approach the intersection, determine where to begin crossing, align for crossing (face the destination corner); determine when to start crossing; and complete the crossing, either independently or by requesting assistance from the researcher, with all or any part of the crossing task.

　

 Researchers intervened while participants were locating the crosswalk and aligning when the starting location and alignment participants identified would result in their crossing the wrong street, or at a clearly hazardous location or direction, such as mid-block where there was no crosswalk. Intervention occurred while crossing the street when participants were in the path of moving vehicles. As long as participants were not directly threatened by moving vehicles, they were allowed to start crossing using a wrong cue, to start from an alignment toward the diagonally opposite corner, or to cross outside the crosswalk.

　

Safety: The longer pedestrians delay starting crossing, the more likely they are to still be in the street after the onset of opposing (perpendicular) traffic. The mean starting delay across all three cities was 6.41 seconds after the onset of the WALK signal or, if participants crossed without actuating the pedestrian timing (and WALK signal) and actuation was required, the number of seconds after the onset of straight-ahead traffic on the street parallel to the participant's direction of travel. Mean starting delay by city was: Portland-5.21 sec.; Charlotte-6.03 sec.; and Cambridge-8.06 sec. The pedestrian interval during which pedestrians begin crossing is also indicative of safety. Pedestrians should begin crossing during WALK, not during flashing or steady DON'T WALK. When they completed crossings after the onset of perpendicular traffic, they were at risk during the end of those crossings. (See Table 1.)