[il-talk] Audible Pedestrian Signals

[Kelly Pierce]

I finally evaluated the current round of audible pedestrian signals
being installed in Chicago. I understand about 20 intersections have
already been outfitted with the technology. I evaluated in the report
below the first installation in my neighborhood and on the north
lakefront. In a nutshell, the walk message is too quiet, environmental
noise is not measured to ensure the audio is louder than surrounding
sound, commonly used street names are not used, and the city fails to
use alert tones in noisy locations. As seen in the report below,
Chicago fails to follow national standards on APS. It seems the City
of Chicago has little connection with other cities that have installed
APS successfully like Boston and San Francisco. I would like to get in
touch with blind leaders who have worked on APS in other cities. I am
highly interested in learning how high quality accessibility was
achieved. Clearly this technology cannot be unboxed and installed.
Some level of customization needs to happen.

Kelly




This is a follow-up communication about my comments regarding the
accessible pedestrian signals at Roscoe and Lake Shore Drive
introduced at an event with city officials on October 9, 2018. I am
blind and have been a Lakeview resident in the 44th Ward for more than
30 years. I have assisted in creating audio interfaces for ATM
machines for major banks, the Cook County and City of Chicago
accessible voting machines and the audible bus announcement system for
the Chicago Transit Authority.  These organizations have received
numerous awards for their accessibility and have served as
international models for superior access for the blind.

Traffic noise at this intersection is among the highest experienced at
Chicago intersections. Yet, the spoken walk announcements cannot be
understood or in some instances heard at all over the noise from the
traffic, when the installation was evaluated during the event. If
accessible pedestrian walk signals are too quiet, they cannot provide
the access they were intended to offer, creating a complete waste of
taxpayer resources and keeping the intersection dangerous for blind
pedestrians.

In an interview with the project’s lead traffic engineer, David
Gleasen, he stated that the City of Chicago currently does not use
decibel meters to ensure the volume of the spoken walk announcement
exceeds traffic noise. In fact, he stated installers have no protocol
whatsoever to ensure blind pedestrians standing at the crosswalk can
actually hear the walk announcement. Further, the APS installation
does not follow federal guidelines and best practices for APS
installation and operation. This includes a walk announcement that
does not meet federal guidelines on spoken walk announcement
construction and a street name in the walk announcement whose
variation is not used by major map providers or the local transit
agency.

The 2009 Manual on Uniform Traffic Control Devices issued by the
Federal Highway Administration in the United States Department of
Transportation offers some guidance on the matter. Section 4E.11.09
states “The volume of audible walk indications and pushbutton locator
tones (see Section 4E.12) should be set to be a maximum of 5 dBA
louder than ambient sound, except when audible beaconing is provided
in response to an extended pushbutton press.” The guideline suggests
the volume expectation should meet or slightly exceed the ambient
traffic sound. The next section states the sound of APS messages
cannot be louder than 100 Db. Because the City of Chicago does not
measure either the environmental sound or the sound of the APS
messages at intersections in installing accessible pedestrian signals,
it is impossible to know whether the signals can be heard above
traffic noise.

Section 4E.11.12 offers the option of “An alert tone, which is a very
brief burst of high-frequency sound at the beginning of the audible
walk indication that rapidly decays to the frequency of the walk tone.
[It] may be used to alert pedestrians to the beginning of the walk
interval.” Subsection 13 follows with “An alert tone can be
particularly useful if the walk tone is not easily audible in some
traffic conditions.”

Section 4E.11.18 sets the standard of how speech walk messages should
be spoken. “Speech walk messages that are used at intersections having
pedestrian phasing that is concurrent with vehicular phasing shall be
patterned after the model: "Broadway. Walk sign is on to cross
Broadway." The messages at Lake Shore Drive and Roscoe do not speak
the name of the street at the beginning of the message. Blind persons
find this important because they cannot read street signs visually and
need to know clearly what street they are walking across not just when
the walk sign is on. When the street name is only at the end of the
message, it likely is not heard by the blind person as traffic begins
to cross the street creating extra environmental noise.  Finally, the
spoken walk announcement calls the street “Local Lake Shore Drive. The
Chicago Transit Authority refers to it as “Inner Lake Shore Drive” in
the name of the 146 bus. Both Apple Maps and Google Maps use “North
Lake Shore Drive.” Open Street Maps uses the name “North Inner Lake
Shore Drive.” It is confusing to blind persons when commonly used
street names are not used and other names for streets not in
widespread usage are used instead.

Based on my evaluation of the intersection along with a review of
federal guidelines and best practices, I make the following
recommendations:

1. Raise the volume on the walk announcement at Roscoe and Lake Shore
Drive so it meets or exceeds environmental traffic sounds at peak
travel times when the listener is standing on the wheelchair ramp at
the crosswalk, unless doing so would exceed 100 db.

2. Place an attention tone at the beginning of the walk announcement
at the Roscoe and Lake Shore Drive intersection so blind pedestrians
can know when to cross without hearing every word of the walk
announcement.

3. Change the spoken walk message at Roscoe and Lake Shore Drive to
add the street name at the beginning of the walk announcement, as
described in federal guidelines.

4. Change the street name in the walk message from “Local Lake Shore
Drive” to Inner Lake Shore Drive” or “Inner North Lake Shore Drive.”

5. Establish a citywide protocol for walk announcement construction
and APS installation so Chicago APS follow federal guidelines and best
practices. The protocol would include testing noise levels with
decibel meters to determine environmental noise levels at peak travel
times and adjusting APS to meet or exceed these noise levels, up to
100 Db.

6. Modify existing APS installations in Chicago to match the
requirements of the protocol.