Functioning of pedestrian signals

Pedestrian signals

Pedestrian signal timing

Intersection Geometry

Figure 10-6. Signalized left turn lane with APS mounted close to the crosswalk locations. Three APS are on the splitter island, one for each crossing.

Streets can be wide and complex, sometimes having narrow medians and channelized turn lanes, which were signalized in some locations.

Roundabouts are used extensively and orientation and mobility specialists and blind travelers state that roundabouts are a barrier to travel.

Detectable warnings or "TWSI's" (tactile walking indicators) are used to define the edge of the street on the curb ramp, but not consistently installed from state to state. The edge of the TWSI is intended to be aligned perpendicularly to the crosswalk direction; this is intended to provide additional directional information to blind pedestrians.

Number of APS

Each state is responsible for its own area.

Overall number was not available.

APS have been fairly extensively installed in areas where there is pedestrian traffic since the 1980s.

APS functioning

Figure 10-7. This APS has a tactile arrow within a larger visible arrow. A raised bar on the tactile arrow indicates that this is an APS. Other features include a locator tone and audible and vibrotactile WALK indication.

Pushbutton integrated type of signal is used. The pushbutton and sound are standardized nationally.

There are several APS manufacturers in the Australian market but the pole mounted control box overhead was the only visible difference. All pushbuttons looked identical, whether they had APS or not, except that those with APS features had an additional raised bar on the arrow to indicate that they had APS. All pushbuttons with audio-tactile features functioned identically.

Locator tone

Locator tone has a repetition rate of once every 2 seconds.

WALK indicator:

Alert tone: "Alert tone" at the beginning of the WALK indication is set to sound at 14 db above ambient.

Additional information


Figure 10-8. Typical APS location in relation to the crosswalk and sidewalk. Australian curb ramp standards allow a steeper slope than allowed by US standards.

Figure 10-9. Installation of tactile arrows was not consistent and provided misleading information in some cases

The standard location of the pushbutton, with each pushbutton located beside the waiting location for the crossing, provided a clear indication of which crossing the APS was indicating. There was no need for different sounds for different directions of travel. Even on pork chop type islands with three devices sounding, it was possible to distinguish the location and crossing being signaled.

Sources of information

George Carnazolla, Transport SA, Adelaide

Gayle Clark, Orientation and Mobility Specialist, Guide Dogs Association of SA and NT, Inc., Adelaide

Susan Lockhart, Orientation and Mobility Specialist, Sydney

Murray Mountain, Access Design Solutions, Melbourne

Bob and Jelena Panich, Bob Panich Consultancy, Ryde (Sydney)

Stephen Purtill, Specifications and Standards, VIC Roads, Melbourne

John Samperi, Signal Engineer

Roley Stuart, Client Services Manager, Guide Dogs Association of SA and NT, Inc., Adelaide

Jack Vankuyk, Traffic Signals Supervisor, RTA Operations, Sydney

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