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From page 135... ... Accessible Pedestrian Signals: A Guide to Best Practice 135 Chapter 7: Installation, Operation, and Maintenance CHAPTER SUMMARY Th is chapter provides guidance for signal technicians who will work directly on the installation of the APS units. In many places, this chapter refers to Chapter 6 illustrations, so readers should have access to both chapters. Read the entire page →
From page 136... ... 136 Chapter 7: Installation, Operation, and Maintenance Review of Design Guidance CURRENT GUIDANCE Th e MUTCD Section 4E.06 recommends: "Th e installation of accessible pedestrian signals at signalized intersections should be based on an engineering study, which should consider the following factors: • Potential demand for accessible pedestrian signals. • A request for accessible pedestrian signals. Read the entire page →
From page 137... ... Accessible Pedestrian Signals: A Guide to Best Practice 137 intersection and the side of the curb ramp. If at all possible, APS should be between 1.5 feet and 6 feet from the edge of the curb, shoulder, or pavement. Read the entire page →
From page 138... ... 138 Chapter 7: Installation, Operation, and Maintenance • Two APS on a single pole with speech messages for the WALK indication, and additional features required with speech messages • Use of pedhead-mounted speakers, possibly with mast arms or another provision in order to locate the WALK indication speakers as near to the associated crosswalk as possible Read the entire page →
From page 139... ... Accessible Pedestrian Signals: A Guide to Best Practice 139 Installation WIRING Wiring needs and availability should be considered before ordering devices because some devices and features require additional wires between the pedestrian signal head, the pushbutton, and the controller. APS typically require an additional control board in the pedestrian signal head or in the controller cabinet. Read the entire page →
From page 140... ... 140 Chapter 7: Installation, Operation, and Maintenance Traffi c signal controllers As stated earlier, APS devices work with current controllers used in the U.S. While Malfunction Management Unit (MMU) Read the entire page →
From page 141... ... Accessible Pedestrian Signals: A Guide to Best Practice 141 Vibrating surfaces Vibrotactile WALK indication should be provided during the associated WALK interval by each APS equipped with a vibrating surface. Th e vibrating surface (arrow) Read the entire page →
From page 142... ... 142 Chapter 7: Installation, Operation, and Maintenance Where speech messages are used for the WALK indication or where there is a pushbutton information message, installer should check that arrow direction and speech messages agree. APS have accidentally been installed with the message providing notiﬁ cation about the wrong street. Read the entire page →
From page 143... ... Accessible Pedestrian Signals: A Guide to Best Practice 143 location. In locations with audible beaconing, a speaker oriented toward the middle of the crosswalk is needed. Read the entire page →
From page 144... ... 144 Chapter 7: Installation, Operation, and Maintenance However, it is most critical that the WALK indication can be heard at the beginning of the crosswalk. Precise orientation of the APS speaker is especially critical at locations with audible beaconing. Read the entire page →
From page 145... ... Accessible Pedestrian Signals: A Guide to Best Practice 145 Setting and evaluating sound levels HOW TO ADJUST APS SOUND LEVELS Th e controls to adjust the settings of the APS vary among the diﬀ erent manufacturers. Th e settings may be adjusted by: • Screws on control board, which may be mounted in pedhead or in the APS speaker unit. Read the entire page →
From page 146... ... 146 Chapter 7: Installation, Operation, and Maintenance • Manufacturers typically set a default maximum and minimum output level on APS devices. Th e settings should be checked to ensure that it is set for 30 dB minimum and 89 dB maximum. Read the entire page →
From page 147... ... Accessible Pedestrian Signals: A Guide to Best Practice 147 • APS at intersections having channelized turn lanes must not be audible from the corners of the intersection. If an APS on the splitter island is too loud, pedestrians who are blind may believe the turn lane is signalized, or that the intersection crosswalk extends all the way to the corner. Read the entire page →
From page 148... ... 148 Chapter 7: Installation, Operation, and Maintenance Measuring sound where audible beaconing is needed At crosswalks where audible beaconing is needed, sound level should be evaluated from the middle of the street, when the loud WALK indication has been called, to be sure beaconing will be provided throughout the crossing. However, current MUTCD language limits the maximum output of APS to 89dB, and most manufacturers preset this maximum. Read the entire page →
From page 149... ... Accessible Pedestrian Signals: A Guide to Best Practice 149 Post-installation checklist CHECKLIST After installation is complete, the installer should perform the following steps (detailed in sections below) Read the entire page →
From page 150... ... 150 Chapter 7: Installation, Operation, and Maintenance AUTOMATIC VOLUME ADJUSTMENT Evaluate and set the sensitivity level of the automatic volume adjustment: • If volumes are adequate in quiet conditions, but do not increase enough or quickly enough when ambient noise increases, the microphone sensitivity, or automatic gain control, may need to be increased. • Increase the microphone sensitivity in 10-20% steps until the response is as desired. Read the entire page →
From page 151... ... Accessible Pedestrian Signals: A Guide to Best Practice 151 CHECK AUDIBLE BEACONING If the intersection requires audible beaconing, • Press the pushbutton for an extended button press and conﬁ rm that the sound is boosted during the following pedestrian phase for the WALK tone and for the locator tone. • Walk across the street during the pedestrian phase and evaluate placement and aim of devices to provide sound in the crosswalk area. Read the entire page →
From page 152... ... 152 Chapter 7: Installation, Operation, and Maintenance Maintenance WHEN AND HOW OFTEN THE APS INSTALLATION SHOULD BE CHECKED As with any complex device, an APS has many features that could malfunction or fail in the course of its operation. If features such as WALK indication, locator tone, or signal interaction fail to work correctly, the resulting lack of information or misinformation for pedestrians who are blind can be dangerous. Read the entire page →
From page 153... ... Accessible Pedestrian Signals: A Guide to Best Practice 153 wrong street (see Figure 7-13) Read the entire page →
From page 154... ... 154 Chapter 7: Installation, Operation, and Maintenance Lessons Learned from APS Installations NEW TECHNOLOGY Not unlike any new technology, the ﬁ rst installation of new types of APS devices does not always operate ﬂ awlessly. Th ere are issues to resolve with some of the devices. Read the entire page →
From page 155... ... Accessible Pedestrian Signals: A Guide to Best Practice 155 • At another location, wires from the parallel crosswalks were switched when attached to the control unit in the controller. Th ose units were programmed for the extended button press to call audible beaconing on the crosswalk, but the sound came from the APS on the parallel crosswalk, rather than from the other end of the called crosswalk. Read the entire page →
From page 156... ... 156 Chapter 7: Installation, Operation, and Maintenance One installation experienced a diﬀ erent problem in adjusting the volume of an APS unit. • Th ey had used the pushbutton control units that install in the cabinet (as opposed to those that install in the pedhead) Read the entire page →
From page 157... ... Accessible Pedestrian Signals: A Guide to Best Practice 157 TACTILE ARROW AND POSITION The tactile arrow is supposed to point in the direction of pedestrian travel on the crosswalk and the face of the device is supposed to be parallel to the crosswalk it controls. SOME INSTALLATION ISSUES: • If the pole is in a poor location, the arrow may be pointing at the street and crosswalk direction but may not be within the crosswalk area. Read the entire page →
From page 158... ... 158 Chapter 7: Installation, Operation, and Maintenance BRAILLE SIGNING AND LOCATION Braille indications on the pedestrian signals have sometimes been mounted backwards or with the braille label for the wrong street. • Manufacturers ship them with a label to clarify positioning for non-braillereaders. Read the entire page →

From page 135...

... Accessible Pedestrian Signals: A Guide to Best Practice 135 Chapter 7: Installation, Operation, and Maintenance CHAPTER SUMMARY Th is chapter provides guidance for signal technicians who will work directly on the installation of the APS units. In many places, this chapter refers to Chapter 6 illustrations, so readers should have access to both chapters.