October 24, 2002
Reference: Audible Traffic Signals and Detectable Warnings.
· Most intersections do not require an ATS for the accessibility and safety of
· Only those intersections with complex geometry, complex signalization, or
varied signalization for each lane may be appropriate for an ATS.
· Vibrotactile indicators should be used in preference to audible signals in
order to minimize noise distractions and better promote safety.
· Locator tones should not be included in the final guidelines and may be
subject to further research.
· At most intersections the built environment provides ample accessible cues to
determine the difference between the sidewalk and the street.
· A slope of less than 1:15 in crossing from the sidewalk to the street
(including medians and islands) may not be detectable and should be identified
with a detectable warning.
I urge the Access Board to reconsider the recommendations made in the recent