October 29, 2002
I realize that I am writing after the end of the comment period, so this message
may be ignored. However, I have been reviewing the comments that have been
posted on your web page, and have been dismayed to read the messages from blind
persons who oppose the implementation of audible traffic signals.
A few years ago I spent three weeks in New South Wales where almost all traffic
signals used audible push buttons. These devices in no way masked surrounding
traffic noises for me, a seeing person. I am sure that blind persons, accustomed
to a more discriminating hearing process, would have even less problem
separating the chirps from the push button from the sounds of surrounding
A few comments about pedestrian push buttons.
In the US today push buttons are frequently not activated, or pedestrians
activate the signal only after waiting 30 seconds for the signal to change. I
have observed attendees of the TRB Convention in Washington regularly fail to
activate the pedestrian phase when crossing the streets surrounding the Marriott
and Sheraton hotels, and this is a population of transportation experts, many of
whom are engineers. If they don't use push buttons, why should we expect more
from the general public?
As a traffic consultant, it has been my experience that most persons have no
concept regarding the intent of push buttons. They expect the push button to
immediately provide them with a pedestrian phase, while in fact pushing the
button only initiates a request for a phase. When the cycle does not quickly
change, these people assume the button is broken.
The public also does not understand that at some signals a pedestrian clearance
time is not introduced unless the button is pushed. They see a car waiting at
the intersection and assume that activation has been signaled and therefore
don't push the button.
I had thought from the literature that chirping pedestrian signal devices were
intended to benefit blind persons. In Australia I discovered that they were a
great benefit for everyone. When approaching a signal, one gently but quickly
becomes aware of the presence of the pushbutton -- it almost invites one to push
it. When pushed, the audible devices provide instant notification that a request
has been initated, increasing confidence in the signal change process.
My other lesson from Australia is that the change in the tone when the walk
cycle commences was a marvelous way of alerting the waiting pedestrian that its
time to cross. Especially when walking with others, but even when walking alone,
I find it easy to become distracted from the exercise of crossing the street and
have even missed the entire ped phase on occaision. In Australia I found that
the change of tone immediately brought me back to the task at hand and I began
crossing the street.
Finally, when I cross a street I seldom spend a lot of time watching the
pedestrian signal head to see if it has entered its warning phase. Instead I am
watching out for turning motor vehicles, the surface of the crosswalk and other
pedestrians. Or if these issues are not a major concern, I enjoy looking at what
is interesting to look at. The change in the audible signal however quickly
alterted me to the fact that I had better start hustling if I wanted to reach
the curb before the cycle ended.
So if the NFB does not want audible signals to be installed to assist blind
persons, I for one wish to express my support for their installation for the
benefit of sighted pedestrians. It may not be a disability issue, but it does
reflect good design practice.