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APS home go to front of Accessible Pedestrian Signals
Go to Front page Background section Travel by Blind
 Research
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Technologies and Features section Types
Pedhead-mounted
Pushbutton-integrated
Vibrotactile
Receiver-based
Walk Indications
Other Features
Choosing and Installing section Where to Install
Designing Installations
New Construction or Reconstruction
Retrofitting an Intersection with an APS
Installation Specifications
Field Adjustments
State of Practices section Case Studies
International Practice
Devices section Manufacturers
Selection Tool
Product Matrix
Downloads section Full Guide
Rating Scales
Field Adjustments
Glossary
 
Pedhead-mounted APS
APS unit mounted on top of pedhead.
Prevalence
The type of APS that has been most commonly installed in the U.S. has a speaker mounted inside or in the vicinity of the pedhead.

Function
Typical functioning of pedhead-mounted devices:
  • The APS emits a sound such as a bell, buzz, birdcall (typically a chirp or cuckoo), speech message, or some other tone during the Walk interval of the signal only.
  • Sound is directly audible, that is, it is heard by everyone in the vicinity; users do not require receivers to hear the sound.
  • May include automatic volume adjustment.
WALK indication
Sound, usually a cuckoo, chirp, or beep, is emitted during the Walk interval only

Vibrotactile information
Not available, except as a separate component sold by one manufacturer

Locator tone
Not typically available; some manufacturers sell the locator tone speakers as a separate component

Installation
As typically installed in the US, pedhead-mounted APS are attached to the pedestrian signal head and aimed toward the opposite curb.
  • Intended to act as a beacon across the street
  • Relatively loud as a consequence
  • Sound from both ends of the crosswalk simultaneously
Pedhead speakers may be aimed in various directions; some cities in California have experimented with aiming the speaker down toward the waiting location and reducing the volume.

Installation examples
Example of Pedhead - mounted APS speaker aimed at pedestrian waiting location. Example of Pedhead- mounted APS speaker aimed toward center of crosswalk.

Tone volume
While pedhead-mounted APS have typically been installed with volume adjusted to be heard across the street, tone volume and speaker alignment can be adjusted so WALK indications are audible only from the vicinity of the waiting area for the associated crosswalk. In most installations, louder signals are a disadvantage. Loud WALK indications coming simultaneously from both ends of a crosswalk are of little or no value in providing beaconing information.

Options
Additional options include:
  • Audible beaconing
  • Locator tone speaker or pushbutton with vibrotactile indications are available from one manufacturer of pedhead-mounted speakers.
Limitations
Speakers must be carefully located so that they are above the end of the crosswalk they signal, or they provide ambiguous information about which crosswalk has the Walk interval.

Recommendations
Devices should be responsive to ambient sound (automatic volume adjustment feature); some devices sold in the US are not.

Draft Public Rights-of-Way Accessibility Guidelines require locator tones at pushbuttons.

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Selection Tool
Audio examples
Audio icon
Mallory chirp
Audio icon
Novax walk tone + message


Campbell
Mallory
Novax
Prisma
US Traffic
Wilcox

Case Studies used in


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