Existing pole location
When the only change is addition of APS at an intersection, the existing pole location at the intersection often restricts the location of the APS components (such as pushbuttons, speakers, and tactile arrows) which can affect the device features needed.
- The location of pushbuttons and tactile arrows and the location of speakers must be carefully engineered to provide accessible and usable information to pedestrians with disabilities.
- Consideration of these issues in designing the installation and ordering devices is needed to avoid providing ambiguous information. Before ordering devices, the designer needs to look at the poles available and determine locations where devices will be installed.
- Pole location may affect the type of WALK indication to be used.
- Location of two APS on one pole requires speech WALK indications.
- APS loudspeakers may be located at the pushbutton location or on the pedhead. The location of these speakers can be critical.
Location of the tactile arrow
Figure 6-14. If pedestrians proceed directly to the curb from the pushbutton in this photo, they will be well outside the crosswalk area when beginning their crossing.
If poles are located too far away from the center of the intersection, outside the extension of the crosswalk lines, the pedestrian who is blind may attempt to cross at a location that is not within the crosswalk area. As discussed in chapter 4, pedestrians may align with the tactile arrow and proceed to the curb from that location.
The installation shown in Figure 6-14 is far more than five feet outside the crosswalk lines extended. While the arrow does clarify which street the device controls, it provides misleading and dangerous information to pedestrians who cannot see.
Figure 6-15. Well-located pedestrian signal poles provide APS audible indications from the optimal location, close to the pedestrian waiting area
If there are no poles at the recommended locations, in retrofit situations, options to consider, in order of decreasing desirability (from the standpoint of minimizing ambiguity), include:
- Repositioning of pedestrian signals and poles, or the addition of stub pole(s) and associated conduit and wiring
- Two APS on a pole with speech messages (see Chapter 4 and Section 4E.11, P13 of the 2009 MUTCD for required wording of speech messages)
- Use of speakers mounted on the pedestrian signal head, possibly with mast arms or other provisions in order to locate the WALK tone speakers as near to the associated crosswalk as possible
Figure 6-16. APS are positioned appropriately at this intersection by the addition of a stub pole for one crosswalk. The stub pole holding the APS for the crosswalk at right is simply bolted to the sidewalk. The other APS is mounted on the pole that supports the pedhead.
1. Repositioning pedestrian signals and poles or adding stub poles
Repositioning poles may be considered a major change in some renovation projects, but may be less difficult when the addition of the APS is part of the upgrading of the curb ramp. The optimal choice is positioning speakers and pushbuttons on poles that are located close to the crosswalk. Possible ways to accomplish this should be strongly considered before other options are explored.
In some locations, the addition of stub poles may be fairly simple. Different jurisdictions have different wiring requirements. The wires to pushbuttons are low voltage wires and it may be possible to run the wires in a saw cut to a pushbutton pole that is surface-mounted to the sidewalk with bolts. Looking at the wiring and the use of stub poles in unconventional ways may provide acceptable solutions to the problems.
2. Installing two APS on one pole
Many jurisdictions use a standard design of two pedestrian signal heads and pushbuttons on one pole. In new or reconstructed intersections, separate poles should be provided at the end of each crosswalk, for the pushbutton to provide unambiguous APS information, and to be maximally useful to all pedestrians. Where two APS pushbuttons are mounted on two separate poles at a corner, their arrows can be readily aligned with each crosswalk. Correct alignment can be difficult to accomplish with two APS on the same pole, particularly at larger radius intersections.
However, if two pushbuttons must be on the same pole, it is essential that speakers be located as close as possible to the pedestrian waiting location and fit the recommendations below for installations of two APS on one pole.
- A speech WALK message is needed, so the user can determine which street has the WALK indication (see discussion of WALK indications in Chapter 4).
- A pushbutton information message and tactile arrow are also needed so that pedestrians can know the direction of the crosswalk served by that pushbutton and the name of the street to be crossed. Without the pushbutton message, the name of the street in the WALK message may still be ambiguous to pedestrians who are unfamiliar with the intersection.
Figure 6-17. Two pedhead-mounted speakers, aimed at right angles to each other are separated by the width of the pedheads and the mounting pole. More distance is preferred and careful aiming and volume control is important.
3. Positioning pedhead mounted speakers near crosswalk
If the available pole is not close enough to the crosswalk location, pedhead mounted speakers may be mounted to extend from the pole to provide the appropriate separation of sounds (see Figure 6-4). Provision of the WALK information at the proper crossing location, even when pushbutton and poles cannot be relocated, may provide some auditory guidance to the pedestrian who is blind about the crosswalk location. This type of installation may not provide the best location for tactile arrows and signs, so if a pushbutton is used, the pushbutton should also provide a locator tone and tactile arrow.
In Figure 6-17, the speakers are positioned on the outside of the pedheads, which somewhat separates the sounds, although more separation is preferred. In these photos the speakers are aimed across the street. The speakers may be aimed directly down in most instances for communication of the beginning of the WALK phase to the pedestrian who actuated the signal. When audible beaconing is needed, the speaker may be aimed toward the center of the street.
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