After an engineering study determines that APS should be installed at an existing signal, strategies for integrating the APS into the sidewalk environment need to address certain issues and/or questions. Those in charge of installing APS at an intersection must conduct a needs assessment to determine which features are suitable in order to develop detailed installation plans. It is important that the installation designer visit the intersection to understand the particular issues that must be dealt with. Some manufacturers require detailed information about the location and infrastructure of the intersection where the APS will be installed in order to send equipment with appropriate arrows or other features (such as speech WALK or pushbutton information messages, if needed).
Pushbutton and pole locations
A high-priority part of the needs assessment is to determine how much of the existing infrastructure can be used and how much will have to be installed or modified. It is essential to look at each crossing and the anticipated location of the pushbutton in relation to the departure location.
Questions to consider:
- Does the pushbutton and pole location fit within MUTCD and Proposed PROWAG recommended locations?
- Is existing wiring adequate for installation of the APS? The manufacturer's devices may have different wiring needs. Some require four wires to be available at the pushbutton where others require two wires. There may be different requirements where audible beaconing is used.
- Is it possible to separate the pushbuttons for two crossings on the same corner by at least 3 m (10 feet)?
- Is the speaker closer to the crosswalk it signals than it is to the other crosswalk?
- Are the pushbuttons located adjacent to a level all-weather surface, free of hazards or obstacles?
- Is there sufficient turning room for a wheelchair if the pedestrian must turn to push the button and then return to the crosswalk?
- If the existing pole is in a "poor" location, can a stub pole be installed? Or, are there other poles nearby that are more appropriately located than the signal pole (e.g., utility poles or lamp posts)?
- Depending upon the pushbutton or pole location, should tones or speech messages be utilized? (if two pushbuttons must be installed on the same pole, speech messages are required for the WALK indication)
Intersection geometry and need for audible beaconing
Audible beaconing is not needed at many intersections, although APS in the United States have traditionally been installed with beaconing.
Questions to consider:
- Is audible beaconing needed at the intersection? (See discussion of audible beaconing in chapter 4 and paragraphs 5 and 6 of MUTCD Section 4E.13 for suggested criteria)
- Would audible beaconing create the potential for confusion? (possible at an intersection with channelized right turns or other free flowing lanes)
Preference and requests
Questions to consider when installation is in response to a request:
- Have the needs of individual requesting the APS been addressed?
[ back to top ]