Accessible Pedestrian Signals

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Accessible Pedestrian Signals

• Presented by
• Joe Couples, P.E.
• Valerie Lee, P.E.

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Legacy devices remain...but mostly new
technology.
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Seattle APS
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Accessible Pedestrian Signals(APS)

• MUTCD 4E.06
• Both audible and vibro-tactile modes identified
  for walk indication.
• Locator tone identified in support section.
• Provides guidance for factors that should be
  considered in study of when to install an
  Accessible Pedestrian Signal.
• APS cannot be by TOD operation.

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Study Factors to Consider

• Potential demand (needs) for APS.
• Requests.
• Traffic Volumes, and turning movements.
• Signal complexity.
• Intersection complexity

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Potential Demand

• High Volume Transit facilities such as Streetcar
  and LRT stations.
• Transit hubs and transfer points.
• Libraries or other facilities for the blind.
• Recreation facilities.

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Requests

• In Seattle
• Until LINK Light Rail and the South Lake Union
  Streetcar, almost all of the APS installations
  were based upon requests.
• Almost all requests were to meet transit,
  shopping, and employment needs of individual(s).

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Traffic Volumes

• Pedestrians may be present at any time.
• Low Volumes.
• High turning volume percentage.

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Traffic Signal Complexity

• Split-Phasing.
• Protected Left or Right-Turns.
• Leading Pedestrian Intervals (LPI).
• Exclusive pedestrian phase.
• Other complicated signal operation.

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Split Phasing
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Intersection Complexity

• Skewed intersection geometry.
• Median islands.
• Free right-turn islands.
• Signal complexity.
• Intersection complexity

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Intersection Skew
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Traffic island
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APS Design Best Practice
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Design Complications

• Underground utilities, MH JB's.
• Curb ramps.
• Decorative poles.
• Light and heavy rail adjacent or in ROW.

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Design Complications
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Median Island APS
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Over-Engineering?
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Errors or Design Standards?
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Which is Correct?
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Office Engineering?
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APS in Operation

• Actuated operation.
• Pre-timed/recall operation.
• APS Controller Unit.

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Actuated Operation

• Pedestrian pushes button to activate.
• Audible and vibro-tactile activate with Walk
  indication.
• Returns to holding mode with Flashing Don't
  Walk.

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Pre-timed Operation in Seattle

• Walk interval comes on automatically without
  the audible vibro-tactile.
• Some devices able to activate audible
  vibro-tactile if adequate clearance time.
• Returns to holding mode with Flashing Don't
  Walk, PBS indicator light goes on.

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APS Settings

• Locator tone is used.
• Audible and locator tone volume settings are
  independently adjustable.
• Volume adjusts to ambient noise so as to be
  quieter at night and other periods.

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Noise Complaints

• Few complaints regarding audible indications.
• Complaints regarding audible mostly by
  multi-story condo or apartment dwellings.
• Many complaints regarding locator tone in
  residential areas.

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APS Prioritization
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Post InstallationCheck List
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APS Sign Message
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Web Resources

• NCHRP Web Document 117A, Accessible Pedestrian
  Signals A Guide to Best Practices. June 2007
• MUTCD 2009

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Questions?