by Mark Greenwood, City of Palm Desert, CA.
The City of Palm Desert has implemented an innovative installation of Americans with Disabilities Act (ADA) compliant design pedestrian push buttons (PPB's). The Public Works Department was contacted in 1996 by a quadriplegic college student, notifying us of his difficulty in actuating the PPB's at a signalized intersection. The student travelled by bus daily to an intersection which is adjacent to the College of the Desert, but because of the severity of his condition, needed assistance to push the PPB in order to cross from the bus stop to the college campus.
Although video detection of pedestrians and wheelchair detector loops in the sidewalk were considered, they were rejected as impractical in this case. Since the City had recently retrofitted high pedestrian activity intersections with ADA design PPB's, a creative application of these buttons was suggested.
It was determined that mounting a supplemental button at 6" above the finished surface would be an appropriate height which allowed the button to be actuated by grazing it with the wheelchair. This application has only recently become a possibility since the ADA button does not have the protective shroud of the standard button, which would interfere in this use. The supplemental PPB is mounted on a standard housing and is wired to the same phase as the standard PPB on each signal pole and is oriented to allow a wheelchair to manoeuvre to easily actuate the button.
This demonstration installation is intended to determine if this solution adequately satisfies a need. Although the student has indicated that the supplemental button functions as intended, no other input has been received. While this may not entirely resolve the issue of detection of disabled pedestrians, this demonstration seems to have been successful. While the potential for vandalism was a concern, there has been no damage in the year since the installation was completed.
For information contact Mark Greenwood, Transportation Engineer, at 760-776-6450.