October 24, 2002
I would like to offer the following comments on the draft regulations and thank
the committee for its considerable efforts. I am blind and am particularly
interested in tactile warnings.
Detectable Warnings (1104.3.2)
Detectable warnings should only be required where the ramp slope was 1:15 or
less. To provide warnings for a greater slope is unnecessary and may even be
In reference to sections as cited below:
Detectable warnings shall consist of a surface of truncated domes aligned in a
square grid pattern and shall comply with 1108.
1108.1.1 Dome Size.
Truncated domes in a detectable warning surface shall have a base diameter of
0.9 inches (23 mm) minimum to 1.4 inches (36 mm) maximum, a top diameter of 50%
of the base diameter minimum to 65% of the base diameter maximum, and a height
of 0.2 inches (5 mm).
The above listed specifications would seem to eliminate or at least not
acknowledge parallel tactile warnings that would act as wayfinding as well as
warning. I am blind and consider wayfinding in some cases an important safety
issue as well.