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Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010) (2011)

Chapter: Chapter 6 - Designing APS Installations

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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Suggested Citation:"Chapter 6 - Designing APS Installations ." National Academies of Sciences, Engineering, and Medicine. 2011. Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010). Washington, DC: The National Academies Press. doi: 10.17226/22902.
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Accessible Pedestrian Signals: A Guide to Best Practice 93 Chapter 6: Designing APS Installations CHAPTER SUMMARY Accessible Pedestrian Signal installations require engineering, including detailed drawings and specifi cations. Complex intersections require complex decisions and the use of engineering judgment. A number of factors must be considered in designing the installation. Th is chapter contains guidance on how to design an APS installation that works well for the user and the environment. CHAPTER CONTENTS Principles 94 Optimal APS Location 95 Signal Phasing Considerations 98 Intersection Geometry Considerations 103 APS Design in New Construction 105 APS Design at an Existing Intersection 109 Needs Assessment 110 Pole Location 112 Specifi cations 115 Mounting and Wiring Issues 117 APS Microphones and Speakers 122 Summary of Recommended Features and Installation Practice 131

94 Chapter 6: Designing APS Installations Principles GENERAL PRINCIPLES IN THE DECISION: • Provide pedestrian signal information to those who cannot see the pedestrian signal head across the street • Provide information to pedestrians about the presence and location of pushbuttons, if pressing a button is required to actuate pedestrian timing • Provide unambiguous information about the WALK indication and which crossing is being signaled • Use audible beaconing only where necessary o Put as little additional sound in the environment as possible o Avoid disturbance of neighbors o Allow pedestrians who are blind or visually impaired to hear the traffi c sounds, as well as the APS FEATURES In many cases, a municipality or state will wish to purchase one style of APS device for all installations. However, there are engineering and design decisions in the installation of APS, as well as in the choice of equipment. More latitude in specifi cations may be applied when the APS is an addition to an existing intersection. Th e Americans with Disabilities Act (ADA) typically requires new construction to meet ADA guidelines, while it requires additions or alterations to meet the guidelines to the maximum extent feasible. Understanding the basic considerations is necessary to designing usable installations in both new and retrofi t situations. In new construction or reconstruction, where the APS can be located consistently, it is likely possible to use standardized device features and mounting locations for all installations. When retrofi tting intersections with APS, it may be necessary to use diff erent features to provide unambiguous information at diff erent intersections. See Chapter 4 for a listing and description of APS features. DEVICE LOCATION Device location is critical to the functioning of the APS and needs to be planned. Th e APS may provide ambiguous information if located incorrectly, just as pedestrian or vehicular signal heads can provide ambiguous, or even dangerous, information if located incorrectly. Engineering judgment is required to determine the best way to install APS at a given intersection and crossing. Diff erences in curb radius, width of right-of-way, presence of a parkway (grass buff er), curb ramp design and location, and existing infrastructure on corners make each installation diff erent.

Accessible Pedestrian Signals: A Guide to Best Practice 95 Whenever possible, two poles should be installed for APS speakers to be located close to the pedestrian departure location and crosswalk, as described in detail below. Recommendations about location and WALK indication have been updated as a result of recent research (see Appendix C for research results). Optimal APS Location Th e optimal location for pushbutton-integrated APS is between the edge of the crosswalk line (extended) farthest from the center of the intersection and the side of the curb ramp. APS should be between 1.5 feet and 6 feet from the edge of the curb, shoulder, or pavement but no further than 10 feet from the edge of the curb, shoulder or pavement. Th ese distances are the same as those recommended for all pedestrian pushbuttons in the Proposed 2009 MUTCD, Section 4E.08.Th e control face and tactile arrow should be carefully aligned with the direction of travel on the associated crosswalk. In order to provide wheelchair users with access to the pushbutton, pushbuttons need to be located adjacent to a level all-weather surface. Pushbutton and speakers for the APS need to be less than 5 feet from the edge of the crosswalk line (extended) farthest from the center of the intersection. At corners of signalized locations where two pedestrian pushbutton and APS are provided, the pushbuttons should be separated by a distance of at least 10 feet (see Figure 6-1). A rapid tick WALK indication is recommended for installations following these guidelines for location. Figure 6-1. Optimal location of pushbutton- integrated APS (two pushbuttons on one corner, mounted on two separated poles — rapid tick WALK indication)

96 Chapter 6: Designing APS Installations When pushbuttons are precisely and consistently located in this way, identifi cation of which crossing is being signaled can be based solely on which pushbutton the WALK signal comes from. Th ere is no need to remember a code (such as cuckoo for a north/south crossing and rapid tick for an east/west crossing) or to understand speech messages. Figure 6-2 provides examples of pole arrangements that meet the requirements for corners having diff erent geometries. Figure 6-3 demonstrates acceptable APS placement at a corner with an improper ramp design. Figure 6-2. Examples of locations for APS on corners with various geometries 10 ft radius, 5 ft sidewalk, parallel ramps 10 ft radius, 5 ft sidewalk with parkway, perpendicular ramps 30 ft radius, 12 ft sidewalk, perpendicular ramps 30 ft radius, 12 ft sidewalk, perpendicular ramps 30 ft radius, 12 ft sidewalk, parallel ramps 30 ft radius, 5 ft sidewalk, parallel ramps 30 ft radius, 5 ft sidewalk with parkway, perpendicular ramps 30 ft radius, 5 ft sidewalk with parkway, perpendicular ramps 30 ft radius, 5 ft sidewalk, single ramp, APS poles separated by 10 ft 20 ft radius, 5 ft sidewalk, single ramp, APS on single pole with speech messages Right-angle right-of- way, 8 ft sidewalk, perpendicular ramps LEGEND Level space APS pole Detectable warning Parkway Ramp slope indication

Accessible Pedestrian Signals: A Guide to Best Practice 97 APS INSTALLATION WHERE TWO SEPARATED POLES ARE NOT POSSIBLE Where the only work being done is the addition of APS to existing poles, or where it is technically infeasible, because of limited right-of-way, topography, or locations of other essential equipment on corners, to install two APS on separate poles on the corner, it may be necessary to install two APS on a single pole. However, the APS features required for this situation are diff erent from those where APS and APS sounds are separated. When it is necessary to mount two pushbuttons on one pole without a separation of 10 feet or more: • speech WALK messages are recommended rather than tones • pushbutton information messages identifying the intersection and the street to be crossed are needed, to be sure users know the street name to listen for in the WALK message Research in Portland demonstrated that the participants’ identifi cation of which crosswalk had the WALK signal was signifi cantly more accurate when the APS provided speech WALK signals from both APS than when the APS used two diff erent tones — cuckoo and rapid tick (see Appendix C). NEED FOR AUDIBLE BEACONING Audible beaconing is the use of an audible signal in such a way that blind pedestrians can home in on the signal from the opposite corner to aid in alignment during the crossing. Th e need for audible beaconing may aff ect the type of device to be installed and the installation location. Not all manufacturers’ devices are capable of providing audible beaconing. Th e need for beaconing should be evaluated and considered early in the design of the installation. A minority of crossings is likely to require beaconing and not all crosswalks at an intersection may need beaconing. Beaconing may actually cause confusion if used at some locations. See Chapter 4 for suggested criteria for audible beaconing. Figure 6-3. Acceptable APS placement at location but inaccessible ramp design (no level space for passage on the sidewalk)

98 Chapter 6: Designing APS Installations Signal Phasing Considerations INTRODUCTION Some signalization schemes, such as exclusive pedestrian phasing and split phasing, need careful adjustment and consideration to avoid confusing pedestrians who are blind. Crossings with pedestrian signals that rest-in-WALK may need special treatment. Th ese issues must be considered in the design phase in determining type of device and location. In addition, careful adjustment of APS volume after installation is essential. SPLIT PHASING Split phasing is a signal design that gives a green phase for all vehicle movements of one direction (e.g., northbound through, right, and left) followed by a phase for all movements of the opposite direction (e.g., southbound through, right, and left). At a location with split phasing, an APS that can be heard from the parallel crosswalk may provide incorrect, confusing, and dangerous information. It is critical that the WALK indication be audible only from the ends of the crosswalk being signaled so pedestrians at other crosswalks do not begin to cross at a time when vehicles are turning across their path in a protected vehicular movement. Th is can be accomplished by locating the APS very close to the crossing location so pedestrians can readily determine which signal applies to their crosswalk. Careful adjustment of the APS volume at all times of the day and night, as well as careful aiming of the speakers is critical. Audible beaconing may not be appropriate at locations with split phasing, due to the possibility of confusion of signals. Possible strategies: • An APS mounted at the pushbutton location with carefully set volume and placement to be heard only at the crossing location (see photos and further discussion in Chapter 7). • A pushbutton that actuates the audible WALK indication only for the crosswalk that received the pedestrian call. ACTUATED TURN PHASING In some timing plans for actuated turn phasing, traffi c in one direction may be held longer to allow the opposing traffi c to complete left turning movements. In many such cases, the pedestrian phases on parallel crosswalks begin at diff erent times. An APS that can be heard from the parallel crosswalk provides incorrect, confusing, and dangerous information and could mislead a pedestrian to cross when vehicles are turning across their path in a protected vehicular movement. Possible Strategies:

Accessible Pedestrian Signals: A Guide to Best Practice 99 • An APS with speakers mounted at the pushbutton, or pedestrian signal head, with carefully set volume and very careful placement and adjustment, to be heard only at the crossing location (see photos and discussion in Chapter 7). • A pushbutton that actuates an audible WALK indication only for the crosswalk that received the pedestrian call. • Having the audible WALK indication sound only during that part of the WALK interval that is common to both of the parallel lanes, provided that the pedestrian clearance time remains long enough to enable pedestrians crossing with audible cues to complete their crossing before the end of the clearance interval. APS WHERE PEDESTRIAN TIMING IS PUSHBUTTON-ACTUATED Pushbutton-actuated pedestrian timing requires a pedestrian to locate the pushbutton and push it to request the pedestrian phase. A pedestrian who is blind needs to know a button-press is required to actuate a pedestrian timing, and needs to be able to fi nd the pushbutton easily. Th e most appropriate way to convey that information is with a locator tone at the pushbutton. Draft Public Rights-of-Way Accessibility Guidelines (Draft PROWAG) require APS with a pushbutton locator tone where there are pedestrian pushbuttons. Likewise, the MUTCD 4E.09 guidance states that “[APS] pushbuttons should be audibly locatable.” See Chapter 4 for a description of pushbutton locator tones. Location of APS pushbuttons for actuated signals To be useful to pedestrians who are visually impaired, pushbuttons must be installed as near to the crosswalk as possible, preferably on the sidewalk within the width of the crosswalk connection or adjacent to the crosswalk, and as close to the curb as possible. Pedestrians who are blind must locate and push the pushbutton, and then align to cross as discussed in Chapter 2. Even with an accessible signal, a pedestrian who is blind or visually impaired may not cross on the fi rst WALK indication, but may need to listen to traffi c and the accessible signal for a cycle to confi rm alignment, the signal functioning, and traffi c direction before pushing the pushbutton again, realigning and crossing on the following pedestrian phase. EXCLUSIVE PEDESTRIAN PHASING Exclusive pedestrian phasing (also known as scramble phasing) is a signal phase when all vehicle movements are stopped and all pedestrian crosswalks are given the WALK signal. Th is makes it diffi cult for pedestrians who are blind or visually impaired to recognize the onset of the WALK interval, particularly at locations where right on red is permitted. In addition, there is no vehicle fl ow to aid in crossing straight to the destination corner. In some locations, pedhead-mounted APS have been installed on all corners and two diff erent sounds for diff erent crossing directions have been set to sound during the

100 Chapter 6: Designing APS Installations WALK indication. Th is is not recommended, as it is confusing to all pedestrians, and pedestrians who are blind typically assume that the signals are broken. Possible Strategies: • Provide the same tone from all APS during the walk interval. • A pushbutton information message, followed by a WALK tone, was used in a pilot project in Morgantown, West Virginia, at an intersection with exclusive pedestrian phasing. Th e pushbutton information message was modeled after the phrase: “Wait to cross Howard at Grand. Wait for red light for all vehicles. Right turn on red permitted.” During the WALK interval, all pushbutton- integrated devices at the intersection emitted the same, rapidly repeating, tone. Only one APS was installed on some corners, with a tactile symbol, with arrows pointing in two directions, installed on the top of the device,. See the Morgantown case study in Chapter 9. • Where mixed exclusive and concurrent pedestrian phasing is used, pushbutton- integrated APS located beside each crosswalk can be used to provide the audible information. APS with speakers mounted at the pushbutton should have carefully set volume and placement to be heard only at the crossing location. REST-IN-WALK At locations where the pedestrian signal to cross the minor street rests-in-WALK, the WALK indication would sound constantly for that crossing. In many locations, that might prove to be irritating to neighbors. Possible strategy: • Some APS manufacturers provide a limit switch that limits the length of the audible WALK indication to seven or eight seconds, but allows recall of the audible and vibrotactile indications of the WALK, if the button is pressed when there is adequate clearance time remaining. Th e availability of that feature should be investigated in the installation planning. APS IN A DOWNTOWN AREA WITH PRETIMED SIGNALS Many agencies in large cities deal with the issue of how to handle APS in downtown areas. Th ese areas are characterized by closely spaced buildings, higher amounts of pedestrian traffi c, and pretimed traffi c signals that often work as part of a coordinated system. Engineers may be resistant to installing pushbutton-integrated APS in this environment for several reasons, such as poles not being located in the appropriate locations, concerns over the nuisance of the APS tones to the surrounding offi ces and shops, and an understandable unwillingness to install a pushbutton at a signal that does not require pushbutton actuation. It is tempting to use only pedhead-mounted APS. However, engineers should recognize that there are still many benefi ts to pushbutton-integrated APS in a downtown area.

Accessible Pedestrian Signals: A Guide to Best Practice 101 Benefi ts of pushbutton-integrated APS in a downtown area Engineers may wonder why they should install a pushbutton-integrated APS if pushing the button has no eff ect on a pretimed signal. Th e key is to realize that pushbutton-integrated APS have several features that are benefi cial to blind pedestrians, even if there is not a need to push the button: • Audible WALK indication — same as for any intersection, the audible WALK indication will let the blind pedestrian know that the walk interval has started so that they will not have to rely solely on traffi c noise. • Locator tone — though it is not necessary that the blind pedestrian fi nd the button to push it, the locator tone is helpful in guiding the blind pedestrian to the proper starting place for making the crossing. For this to be helpful, it is important that the pushbutton pole is located correctly (i.e., close to the pedestrian departure point). • Tactile arrow — the tactile arrow provides information about which crosswalk is being signaled and what is the location and direction of that crosswalk. • Vibrating surface — pedestrians with poor hearing can keep their hand on the vibrating surface and know when the walk interval has started. Sound issues in a downtown area Engineers and city offi cials may also be concerned about the amount of noise that pushbutton-integrated APS will introduce to the downtown area. It must be understood that APS are not intended to be loud devices, and they should not be confi gured as such. Refer to Chapter 7 for sound level specifi cations. Th ose installing APS should calibrate the sound carefully and be aware of the fact that sound will refl ect off the closely spaced buildings in a downtown area. Audible signals mounted on the pedestrian signal head When the addition of the APS is the only change planned at an intersection with pretimed signals, and a pushbutton absolutely cannot be installed in a location where the tactile arrow and vibrotactile information associated with the pushbutton is usable, it makes little sense to install an APS with those features. A pedhead-mounted APS without a pushbutton or locator tone may be appropriate in that situation. Th is suggestion does not apply at new or reconstructed intersections. An installation without the tactile arrow and vibrotactile WALK indication would not comply with the Draft PROWAG requirements for new construction. Such an installation Figure 6-4. The mast arm is used in this installation in Toronto, Canada to position pedestrian signal head and speaker closer to the crosswalk.

102 Chapter 6: Designing APS Installations might be considered to meet them to the maximum extent feasible, when existing conditions and structures prevent installation of additional poles to mount the APS beside the crosswalk. When an APS is mounted on pedestrian signal heads, the WALK message or tone and volume levels should be carefully determined to avoid confusion to pedestrians, and to prevent disturbance to neighbors. Unless audible beaconing is determined to be necessary, the APS speaker should be oriented down toward the waiting location of the pedestrian. Use of a small mast arm to locate the APS optimally over the crosswalk location might be appropriate (Figure 6-4).

Accessible Pedestrian Signals: A Guide to Best Practice 103 Intersection Geometry Considerations EFFECT ON APS An APS that is audible from the wrong crossing location may lead a visually impaired pedestrian to begin to cross at the incorrect time and place. Geometric features, such as unsignalized and signalized right turn lanes, have been recognized as situations of concern in language in the MUTCD. Th e type of APS may not be as important as the location of the sound source and volume of the WALK indication. Th ese issues must be considered in the design phase in determining type of device and location. Also, careful adjustment of APS volume after installation is essential. UNSIGNALIZED RIGHT TURN LANES AND SPLITTER ISLANDS An unsignalized right turn lane can pose a problem if the APS for crossing the signalized main through lanes of the intersection is too loud. Pedestrians who are unaware of the existence of an unsignalized right turn lane may reach the curb, hear the APS sounding and cross the unsignalized lane, thinking that it is signalized. Th is concern is the reason that MUTCD 4E.06 urges careful selection of tones at locations with free right turns. However, tone selection does not really provide a solution; volume of the sound and placement of the speaker are the important issues. Th e Proposed 2009 MUTCD has been revised to state that “the sound level of audible pedestrian indications should be adjusted to be low enough to avoid misleading pedestrians who have visual disabilities…” at locations with unsignalized right turn lanes. Th e APS must be adjusted so it is only heard from the location where the pedestrian is waiting to cross and only audible for the crosswalk being signaled. It is generally not appropriate to use audible beaconing where there are splitter islands because the volume cannot be controlled precisely enough. As discussed in the section on split phasing, volume and placement of the sound source are critical considerations in designing and installing the APS. In Figure 6-5, a pedestrian standing on the corner at location A should not be able to easily hear the APS that is located on the splitter island and intended for use by pedestrians crossing the through lanes. Figure 6-5. APS at channelized turn lane

104 Chapter 6: Designing APS Installations SIGNALIZED CHANNELIZED RIGHT TURN LANES Where crosswalks from corners to splitter islands are signalized, the signals to cross to the island might not be concurrent with traffi c movement parallel to the pedestrian who is blind, depending on the crossing location. APS should be located precisely next to the associated crosswalks with careful volume adjustment. Pedestrians waiting on the island must not confuse the WALK indication for the turn lane with the WALK indication for the through lanes of the intersection. Pedestrians approaching the corner can also be guided to the crosswalk by a locator tone in combination with curb ramp location. Because signalized right turn lanes can be confusing for pedestrians who are blind, installation of APS with pushbutton locator tones at signalized right turn lanes should be given high priority. MEDIANS If the pedestrian clearance time is suffi cient only to cross to a median having an additional pushbutton, it is very important that the pushbutton on that median be an APS with a locator tone. Th is may inform the pedestrian who is visually impaired that a second button press is needed to complete the crossing, and will aid in location of the median and the pushbutton. If only one APS device is on the median, the pushbutton should have a double-ended arrow. If pedestrian phases for the two halves of the street are timed separately, two pushbutton-integrated APS are needed on the median, separated by as much distance as possible, and located as close to each crossing departure location as possible. In addition to the locator tone of an APS, a fence and off set crosswalks are used in European and Australian cities to alert all pedestrians about the need to stop on the median and wait for the next pedestrian phase. At this median island in Ireland (Figure 6-6), an APS is provided for each crossing, and a fence prevents pedestrians from continuing straight across the street, requiring the pedestrian to turn and walk to the other crosswalk location and pushbutton. Figure 6-6. APS at median midblock crossing

Accessible Pedestrian Signals: A Guide to Best Practice 105 APS Design in New Construction DRAFT PROWAG Revised Draft Public Rights-of-Way Accessibility Guidelines (Draft PROWAG) were released on November 23, 2005. While Draft PROWAG has not been published as a fi nal rule, it should be considered as the best guidance available at this time (Isler memo, 2006). APS CHARACTERISTICS Th e Draft PROWAG requires APS with the following features in new construction and reconstruction where pedestrian signals are installed: • APS devices integral with the pushbutton • Audible and vibrotactile indications of the WALK interval • WALK indication by tone or speech message • Pushbutton locator tone wherever there is a pedestrian pushbutton • Pushbutton that is a minimum of 0.5 cm (2 in) across in one direction and that contrasts visually with its housing or mounting • Tactile arrow indicating the direction of travel on the crosswalk, and • Braille or verbal information about the name of the street. Optional features Th e Draft PROWAG states that an extended button press shall be permitted to activate additional features. However, no information is provided which specifi es what those features may include (see Chapter 4 for discussion of extended button press and possible features). Location in new construction Th e Draft PROWAG specifi es that APS devices shall be located as follows: • In such a way that the vibrotactile feature can be contacted from the level landing of a curb ramp, or from clear ground space in line with the crosswalk line adjacent to the vehicle stop line, • Within specifi ed reach ranges from a level landing, • 3 m (10 ft) minimum from other APS at the crossing, with an exception to that distance for devices installed on medians, and Figure 6-7. APS installation in new construction

106 Chapter 6: Designing APS Installations • With control face of the device installed facing the intersection, parallel to the direction of the crosswalk it serves. • Clear fl oor or ground space at the pushbutton shall connect to or overlap the pedestrian access route. MUTCD recommended locations MUTCD recommendations do not specify the locations for new construction in the same manner, but are substantially the same as locations required in new construction and reconstruction by Draft PROWAG. MUTCD 4E.09 states “Pushbuttons for accessible pedestrian signals should be located… as follows: • Adjacent to a level all-weather surface to provide access from a wheelchair, and where there is an all-weather surface, wheelchair accessible route to the ramp; • Within 1.5 m (5 ft) of the crosswalk extended; • Within 3 m (10 ft) of the edge of the curb, shoulder, or pavement; and • Parallel to the crosswalk to be used.“ In the Proposed 2009 MUTCD, Section 4E.09 states that APS detectors should be located close as possible to the crosswalk line furthest from the center of the intersection and as close as possible to the curb ramp. In Section 4E.08 of the Proposed 2009 MUTCD, the locations for all pushbuttons (pedestrian detectors) has been revised to require that all pushbuttons to be located within 5 feet of the crosswalk line extended and within six feet of the edge of the curb, except at locations “where there are constraints that make it impractical to place the pedestrian pushbutton between 0.45 m (1.5 ft) and 1.8 m (6 ft) from the edge of the curb, shoulder, or pavement.” In that case, it should not be farther than 3 m (10 ft) from the edge of curb, shoulder, or pavement.

Accessible Pedestrian Signals: A Guide to Best Practice 107 Figure 6-8. Ideal placement for pushbutton- integrated APS Figure 6-9. Acceptable placement for pushbutton- integrated APS

108 Chapter 6: Designing APS Installations Figure 6-10. The APS should be located on the intersection side of the pole, as shown in this photo Figure 6-11. The MUTCD states that the APS should be within 5 feet of the crosswalk line extended Figure 6-12. The APS should be within 10 feet of the curb Figure 6-13. APS installed in this reconstruction location are in accordance with the Draft PROWAG in that they are beside a level landing and separated from each other by at least 3 m. Both APS are located on the intersection side of their poles.

Accessible Pedestrian Signals: A Guide to Best Practice 109 APS Design at an Existing Intersection APPLICATION OF NEW CONSTRUCTION GUIDELINES In retrofi t situations, the ADA requires that new construction guidelines be followed to the maximum extent feasible, if compliance with the new construction guidelines is technically infeasible. Th e determination of technical infeasibility will vary depending on the scope of the project and the existing situation. Th e new construction guidelines, as described in the previous section, should be applied as much as possible given the constraints of the project and the site. Th e following sections provide guidance to assist the engineer/designer in understanding the eff ect of varying locations and diff erent actuation on the usability of the information provided by APS. AVOIDING AMBIGUITY Th e goal of the new construction location requirements and guidelines is to provide unambiguous information about which crosswalk has the WALK indication, and to make pushbuttons accessible to and usable by all pedestrians, including those with visual and mobility impairments. Poor location and installation can render APS unusable by a pedestrian who is blind or mobility impaired or can provide dangerously incorrect information. Pedhead-mounted and pushbutton-integrated APS in the U.S. have typically been mounted on the same pole as the pedestrian signals for that crosswalk, regardless of whether the pedhead is the one closest to that crosswalk. Th is does not always provide unambiguous audible WALK indications. In Australia and some European countries, it is common to install a separate stub pole to mount APS in a consistent location in relation to crosswalks. Th is consistent location makes it easy to determine which device the WALK indication is coming from, and, therefore, provides unambiguous information regarding which crosswalk has the WALK interval. Draft PROWAG implements this strategy in new construction in the U.S. ISSUES TO CONSIDER In designing retrofi t installations, an understanding of the eff ect of certain intersection features on APS use will be helpful in making decisions. Another factor that becomes critical when adding APS to an existing intersection is the location of existing poles and the possible need for new poles to position the APS close to the crosswalk. Details on these issues and recommended solutions are given in the following sections.

110 Chapter 6: Designing APS Installations Needs Assessment STRATEGIES 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. Th ose 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 modifi ed. 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 fi t within MUTCD and Draft PROWAG recommended locations? • Is existing wiring adequate for installation of the APS? Th e manufacturer’s devices may have diff erent wiring needs. Some require four wires to be available at the pushbutton where others require two wires. Th ere may be diff erent 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 suffi cient 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 should be used for the WALK indication)

Accessible Pedestrian Signals: A Guide to Best Practice 111 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 for suggested criteria) • Would audible beaconing create the potential for confusion? (possible at an intersection with channelized right turns or other free fl owing 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?

112 Chapter 6: Designing APS Installations Pole Location EXISTING POLE LOCATION When the only change is addition of APS at an intersection (usually in response to a request), the existing pole location at the intersection often restricts the location of the APS components (such as pushbuttons, speakers, and tactile arrows) which can aff ect the device features needed. • Th e 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 aff ect the type of WALK indication to be used. o Location of two APS on one pole requires either speech WALK indications, additional mast arms, or other provisions to separate the sounds. o APS speakers will usually be located at the pushbutton location. In some situations, they may be on the pedhead. Th e location of these speakers can be critical. Location of the tactile arrow 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. Th e installation shown in Figure 6-14 is far more than fi ve 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. THREE OPTIONS If there are no poles at the recommended locations, in retrofi t situations, options to consider, in order of decreasing desirability (from the standpoint of minimizing ambiguity), include: 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.

Accessible Pedestrian Signals: A Guide to Best Practice 113 1. Repositioning of pedestrian signals and poles, or the addition of stub pole(s) and associated conduit and wiring 2. Two APS on a pole with speech messages (see Chapter 4 for recommended wording of speech messages) 3. 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 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 diffi cult when the addition of the APS is part of the upgrading of the curb ramp. Th e 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. Diff erent jurisdictions have diff erent wiring requirements. Th e 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. Figure 6-15. Well-located pedestrian signal poles provide APS audible indications from the optimal location, close to the pedestrian waiting area 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.

114 Chapter 6: Designing APS Installations 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 diffi cult 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 fi t 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 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. 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. Th is 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. In most instances, the speakers may be aimed directly down toward the waiting area 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. 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.

Accessible Pedestrian Signals: A Guide to Best Practice 115 Specifi cations When ordering APS units from the manufacturer, practitioners will need to be specifi c concerning the features and settings that they desire or require. Th e level of detail required by the manufacturer varies depending on the company. Elements of a specifi cation sheet should inform the manufacturer of the characteristics of the location where the APS will be installed and which APS features will be required by the city or state. Th e following list contains suggested elements for a detailed specifi cation sheet. APS units do not necessarily need to have all these features, but the practitioner should be sure to consider the appropriateness of all features and specify which ones are required for the selected APS installation. • Type of WALK indication required (tone or speech message) • Text and name of street if speech WALK indication is used • Requirement for “extended button press” function and specifi cation as to what this function would need to do (e.g., provide pushbutton information message, provide louder WALK indication, etc.) • Requirement for vibrotactile arrow • Requirement for pushbutton information message • Text for pushbutton information message (if used) • Requirement for audible, visual, and/or tactile feedback of pushbutton activation • Orientation of tactile arrow for each unit • Text to be encoded into Braille for imprinting on pushbutton or informational sign • Anticipated mounting (wood or metal pole) • Required location of control unit (ped head or cabinet) • Required factory settings for o WALK indication volume (minimum and maximum and amount over ambient) o Locator tone volume (minimum and maximum and amount over ambient) • Electrical operating requirements (e.g., voltage, etc) • Wiring requirements (e.g., number of wires, gauge) • Required operating temperature range • Requirement for built-in WALK/DONT WALK confl ict detection • Warranty duration and coverage • Follow-up support and assistance available from the manufacturer

116 Chapter 6: Designing APS Installations It is also useful to include an intersection diagram showing: • crosswalks to be controlled • pushbutton locations • speaker locations and angle (if pedhead-mounted speakers are desired)

Accessible Pedestrian Signals: A Guide to Best Practice 117 Mounting and Wiring Issues LOCATION OF CONTROLLER BOARDS AND WIRING Wiring Pushbutton-integrated APS may require an extra set of wires to the pushbutton to power the audible indications. APS with actuation indicators may need to receive an actual signal from the controller that the call has been accepted. If the conduit is not adequate for extra wiring, plans for installation may require conduit and wiring replacement. However, some manufacturers now provide devices that can replace typical pushbuttons and require only two wires and an additional control unit in the controller cabinet. Some APS manufactured abroad initially required 110 volt AC power to the push button rather than DC power. Th ese manufacturers now supply APS models to the U.S. market that are adapted to provide DC power to the pushbutton. It may be necessary to specify that devices meet U.S. requirements. Traffi c signal controllers APS devices work with current controllers used in the U.S. In installations from 2000 – 2003, some controller confl icts were reported, mainly related to a change in voltage that leads to the Malfunction Management Unit (MMU) override. Th ese have been addressed by the manufacturers and seem to be resolved. In 2002, the Access Board funded a project to investigate problems that found that many issues that had been reported were due to incorrect installation or sound adjustment problems. Th e fi nal project report is available on the access board website at www. access-board.gov. Mounting APS controller boards Some APS have a control board that is completely contained within the pushbutton. Other APS require a separate control board that is mounted in the pedhead (see Figure 6-18), while still others require a control unit mounted in the controller cabinet. Th e control board often includes voice or sound chips and switches to control volume, microphone response and other features. Some types of pedheads do not have adequate space to mount APS control boards. For example, incandescent, 12 inch over/under pedheads may not have adequate space. Th ese pedestrian signal heads can be replaced. Other options may include: Figure 6-18. APS device with control board in pedhead-mounted speaker (speaker opened for illustration)

118 Chapter 6: Designing APS Installations • Manufacturers may be able to supply a separate case for the APS control board (see Figure 6-19). • APS control boards may be mounted in the signal controller. However, the correct gauge wires must be calculated to drive the speakers when wiring is extended across the street/intersection. Included wiring is usually only adequate to drive the speakers when run from the pedhead. If an area typically experiences high winds, it may be necessary to mount the APS speaker on a strong surface. Engineers in Nova Scotia found that speakers mounted on the plastic pedhead were prone to cracking off during times of high wind. Th eir solution was to mount the speakers directly to the metal pole, as shown in Figure 6-21. Vibrating surfaces Vibration-only devices are not recommended. However, pushbutton-integrated APS should have a vibrotactile arrow that vibrates during the WALK interval. The vibrotactile arrow can be useful in confirming the audible WALK indication and providing WALK signal information to individuals with impaired hearing. Designers/engineers and installers must remember that the vibrating surface will be usable only if they are installed within the width of the crosswalk or very near the crosswalk, and near the curb line. Pedestrians must be in an appropriate position to begin their crossing while waiting with their hand on the vibrating surface. Orientation of tactile arrow Th e tactile arrow must be oriented parallel to the direction of travel on the crosswalk controlled by the pushbutton. Arrows on several manufacturers’ devices are positioned by the installer; however, with some devices, the direction of arrow is specifi ed when Figure 6-19. External mount for controller board is visible on the left side of the pedestrian signal head Figure 6-20. Controller Board mounted inside 18- inch pedestrian signal head Figure 6-21. APS speaker mounted directly to the metal pole for more support during high wind

Accessible Pedestrian Signals: A Guide to Best Practice 119 ordering the units. Th e pole location in relation to the crosswalk can aff ect the direction of the arrow. Wooden poles In areas where pushbuttons are installed on wooden poles, the wiring usually runs within a conduit on the outside of the pole. A mounting bracket is needed on some devices for wiring the pushbutton. Th is bracket needs to be ordered with the APS. Pedestrians who are blind have expressed concerns about nails and staples that are common on wooden poles and which present a hazard for their hands when locating the button (see Figure 6-26). Innovative solutions include the use of a shield for the pole area near the pushbutton to solve this problem, as shown in Figure 6-27. Stub poles Th e use of stub poles for mounting pedestrian pushbuttons is common in some areas of the U.S. Th ey provide an opportunity to locate the pushbutton where it is most usable to pedestrians and may improve pedestrian compliance with pushbutton use. Stub pole examples Braille labels and signs Before ordering APS with Braille labels on the faceplate, you must know: • Th e location of the pole, and • Which side of the pole the APS will be mounted on Th e direction of the face plate and associated arrow is determined when the raised dots of Braille are added. Braille is generally just punched into the metal plate. Figure 6-22. The direction of the cast-in-place arrow on this device must be specifi ed when ordering Figure 6-23. Mounted on a wooden pole, an additional mounting bracket is installed to allow the wires to run from the conduit into the top of the pushbutton- integrated device. Figure 6-24. Typical installation without extra mounting plate, with wire running from inside the metal pole into the back of the device

120 Chapter 6: Designing APS Installations Figure 6-25. This APS is mounted on a wooden pole by drilling a hole through the pole and running wires through the back of the device Figure 6-26. Wooden pole with nails and staples that are typical and a source of concern Figure 6-27. Coated canvas shield used in Charlotte, NC Figure 6-28. A stub pole is used to locate the pushbutton beside the sidewalk Figure 6-29. Stub pole example Figure 6-30. Stub pole installed near sidewalk signal box simplifi es wiring and locates ped pushbutton by the crosswalk

Accessible Pedestrian Signals: A Guide to Best Practice 121 Figure 6-31. Stub pole example Figure 6-32. Braille label is below the raised print street name

122 Chapter 6: Designing APS Installations APS Microphones and Speakers MICROPHONE LOCATION Some APS require installation of microphones to monitor the ambient sound; this is part of the automatic sound adjustment feature. Th e microphones measure the sound levels to adjust the volume at the waiting location. If the microphone is mounted too far from the intersection, it will not adequately sample and adjust the volume levels, and the WALK indication is likely to be too quiet for a pedestrian at the curb to hear above the sound of traffi c. APS SPEAKERS Th is Guide focuses on pushbutton-integrated APS, due to the fact that this is the emerging state-of-the-art technology for APS and Draft PROWAG and the Proposed 2009 MUTCD require APS to be integrated with pushbuttons. However, the authors recognize that many agencies may still be using APS that are pedhead- mounted only. Such pedhead-mounted APS are typically equipped with a standard pedestrian pushbutton (not enabled with raised arrow or vibrotactile function) and an overhead speaker which provides an audible indication of when the walk interval begins. Even if an agency is using pushbutton-integrated APS, some manufacturers also provide the option of having a speaker at the pedhead in addition to a speaker at the pushbutton location. Th is may be particularly useful where audible beaconing is installed, to focus the audible beaconing signal. Th ere are diff erent issues to be considered for the APS installation design, depending on the speaker location. Th e following sections will provide guidance for each of the two general speaker locations. PUSHBUTTON-INTEGRATED SPEAKERS Sound dispersion from pushbutton-integrated speakers While the speaker is usually built into the pushbutton-integrated device, diff erent devices have slightly diff erent speaker locations, and this aff ects the volume settings and the mounting of the device. If possible, particularly in a location with audible beaconing, the devices should have speakers oriented toward the street, as well as the sidewalk and pedestrian waiting location. Beaconing is unlikely to be successful when provided by a device without speaker openings on the curb side. Th e addition of a pedhead-mounted speaker may need to be considered in a situation requiring beaconing. Some manufacturers sell optional add-on speakers or baffl es to control direction of sound, when needed.

Accessible Pedestrian Signals: A Guide to Best Practice 123 H-frame for pushbuttons An H-frame is used for mounting pushbuttons in some northwestern states. Some APS devices will not work properly when mounted in this confi guration. Th e type of device and location of speaker components should be considered before ordering. Th e arrow of the APS is often part of the pushbutton and may not be oriented properly in the H-frame. In addition, the design of the frame makes it diffi cult to hear the sound of the locator tone from both the approach direction and the crossing direction. It can be helpful for pedestrians who are blind to hear the locator tone as they complete their street crossings (the WALK indication is seldom still sounding by that time). In this type of mounting, the pushbutton locator tone is not audible from the street because the speaker is aimed back toward the building line. If two pushbutton-integrated APS in H-frames are mounted on a single pole, they will provide ambiguous WALK indications because the APS closest to each crosswalk will be indicating the perpendicular crosswalk, not the closest crosswalk. Th e speaker for the locator tone in Figure 6-36 is oriented toward the building line, rather than toward the street (in the location shown in the photo, the WALK indication comes from an overhead speaker). One of the arrows points toward the pole and the other device, as well as toward the street, but it would be hard to use the arrow for direction when standing on the sidewalk side of the pole. Illustrations of ideal, acceptable, and unacceptable locations of pushbutton-integrated devices and speakers Th e drawings on the following pages illustrate proper and improper positioning of pushbutton-integrated devices and speakers. In the following captions, “retrofi t” refers to the installation of APS at existing intersections. A retrofi t might involve some constraints on the installation process, such as the inability to have two separate poles on a single corner. It is assumed that the sidewalk beside the pushbutton is fi rm and level as required by Draft PROWAG. Figure 6-33. Speaker grille on side of APS Figure 6-34. Speaker grille on front and side of APS Figure 6-35. Example of H-frame pushbutton Figure 6-36. H-frame APS mounted to pole

124 Chapter 6: Designing APS Installations Figure 6-38. Acceptable placement for pushbutton- integrated APS Figure 6-39. Acceptable placement for pushbutton- integrated APS, only when installing in a retrofi t situation on an existing pole (if APS cannot be separated, there will need to be a speech pushbutton information message and speech WALK message to prevent ambiguity)

Accessible Pedestrian Signals: A Guide to Best Practice 125 Figure 6-40. Acceptable placement for pushbutton- integrated APS, only when installing in a retrofi t situation on an existing pole (if APS cannot be separated, there will need to be a speech pushbutton information message and WALK message to prevent ambiguity). Additionally, the face of the APS does not face the intersection, as is required in the Proposed 2009 MUTCD. Figure 6-41. Unacceptable placement for APS speakers (the positioning provides ambiguous information)

126 Chapter 6: Designing APS Installations PEDHEAD-MOUNTED SPEAKERS Sound from pedhead-mounted speakers Th e sound from pedhead-mounted speakers is not very useful for providing guidance about the location of the opposite curb. Unless audible beaconing is required, speakers should be aimed down toward the pedestrian waiting location. Speakers may be aimed toward the center of the street at crosswalks where beaconing is needed. For pedhead- mounted speakers, sound will travel farther the more nearly horizontal the radiation pattern of the speaker is. • Where beaconing is not needed, speakers should be pointed down toward the location of pedestrians waiting to cross the associated crosswalk, which will also minimize noise in neighborhoods. • Where beaconing is needed, the speaker must be pointed toward the middle of the associated crosswalk (centerline of the road). A side eff ect of this design is that the APS will produce more noise in the neighborhood. Figure 6-42. Unacceptable placement for pushbuttons and tactile arrows of APS (not reachable from level all-weather surface) Figure 6-43. This photo shows a view from below of a speaker attached to the pedhead support and aimed straight down

Accessible Pedestrian Signals: A Guide to Best Practice 127 Speaker location While the direction of the speaker does make a diff erence, it is common for overhead speakers that are attached to pedheads to provide ambiguous information. Figure 6-44 illustrates such a speaker and pedhead placement. In both cases, the mounting is problematic because the speakers are mounted on a pedhead that is not over the departure location of the crosswalk they signal. Th e speaker in Figure 6-44 is located on the side of the pedhead and sounds for the north/south crosswalk. It is situated directly over the waiting area to cross to the east and some distance from the north/south departure point. Th is confi guration can be very confusing to pedestrians who are blind. Acceptable and Unacceptable Locations of pedhead-mounted speakers Th e drawings on the following pages illustrate proper and improper positioning of pedhead-mounted devices and speakers. Figure 6-44. The pedhead and APS speaker for the north/south crosswalk is located over the pushbutton for the east/ west crosswalk Figure 6-45. Possible placement for APS speakers mounted on the pedestrian signal head at pretimed signals; no beaconing

128 Chapter 6: Designing APS Installations Figure 6-46. Recommended placement for pedhead- mounted speakers where beaconing is needed Figure 6-47. Possibly acceptable placement for pedhead-mounted APS on the outside of the pedheads. Provide as much separation as possible.

Accessible Pedestrian Signals: A Guide to Best Practice 129 Figure 6-48. Possibly acceptable placement for pedhead-mounted APS using mast arms to provide additional separation Figure 6-49. Unacceptable placement for pedhead- mounted speakers, regardless of how speakers are aimed

130 Chapter 6: Designing APS Installations Figure 6-50. These APS speaker placements are unacceptable, regardless of how speakers are aimed Figure 6-51. These APS placements are unacceptable, regardless of how speakers are aimed

Accessible Pedestrian Signals: A Guide to Best Practice 131 Summary of Recommended Features and Installation Practice APS INSTALLATION IN NEW CONSTRUCTION Recommended features • Rapid tick WALK indication, no more than 2-5dBA above ambient sound • Vibrotactile WALK indication • Speaker and vibrotactile indication located at pushbutton • Pushbutton locator tone • Tactile arrow on each device aligned in direction of travel on the crosswalk • Braille or audible street name Recommended installation • Precise location of the APS is very important to prevent ambiguity about which crosswalk is being signaled • APS should be reachable from the level landing of the curb ramp for the crossing or from a level surface with an accessible path to the ramp • APS should be within 5 feet of the extension of the crosswalk lines and within 10 feet of the curb • Tactile arrow should be aligned with the direction of travel on the crosswalk • Face of the device oriented toward the intersection (APS should be located on the intersection side of the pole) • Th e APS on the same corner should be a minimum of 3 m (10 ft) apart • Pushbutton should be located within reach range for wheelchair users APS INSTALLATION AT EXISTING LOCATIONS (NOT NEW CONSTRUCTION) New construction guidelines should be met to the maximum extent feasible. • Pushbutton-integrated APS must be located close to the crosswalk (see Optimal APS Location, pages 6-4 through 6-8) • If it is not possible to mount two APS on the same corner a minimum of 10 feet apart, an APS providing a speech message during the walk interval, as well as a pushbutton message, is recommended • If a pedhead-mounted APS speaker is used, it must be above the waiting location of the crosswalk being signaled (see Pedhead-mounted speakers, pages 6-52 through 6-61)

132 Chapter 6: Designing APS Installations CONFIGURATION-SPECIFIC RECOMMENDATIONS Below are listed some specifi c situations in which there are installation recommendations in addition to the ones listed above for new construction and existing construction. Th e recommendations listed for each situation below are only the areas where they diff er from the general recommendations listed above. Unless otherwise specifi ed, all other above recommendations apply to each situation. APS installations where beaconing is needed APS at intersections where beaconing is needed should have certain features and installation, whether they are used in connection with pretimed or actuated signals. • Loud locator tone during the fl ashing DONT WALK of the subsequent pedestrian phase only, in response to an extended button press, from speakers at the pushbutton or pedestrian signal head. If mounted high, speakers should be aimed diagonally down and out into the center of crosswalk indicated by that APS. If possible, beaconing sound should come from the far side speaker only (this requires special equipment and wiring). • Sound should be increased only for the requested crosswalk • Location of all speaker components of the APS within the width of the crosswalk is essential, as users will direct their travel toward the source of the sound (see Figures 6-46 through 6-51 for example drawings) APS at pretimed intersections where beaconing is not needed (not new construction) • If pushbutton-integrated APS cannot be located at the pedestrian waiting area, pedhead-mounted APS (which do not provide vibrotactile indications) must be above the waiting location of the crosswalk being signaled and should be aimed down toward the waiting location APS at corners where two pushbuttons must be mounted on the same pole (not new construction) • Speech WALK indication, two to fi ve dBA above ambient sound • Pushbutton information message to provide intersection and crosswalk identifi cation information • Speech messages should follow the recommendations for wording, and the APS should be positioned within 10 feet of the curb (see page 6-29 and Figures 6-39, 6-40, 6-41, 6-47, and 6-48)

Accessible Pedestrian Signals: A Guide to Best Practice 133 Figure 6-52. Example of pushbutton information messages and speech WALK messages for two APS located on the same pole

134 Chapter 6: Designing APS Installations

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TRB’s National Cooperative Highway Research Program (NCHRP) Web-Only Document 150: Accessible Pedestrian Signals: A Guide to Best Practices (Workshop Edition 2010) provides an introduction to accessible pedestrian signals (APS) and highlights issues related to the design, installation, operation, and maintenance of APS.

The report also addresses public education, U.S. case studies, and international practice related to APS. In addition, the report explores issues related to travel by pedestrians who are blind or who have low vision, and examines traffic signals and modern intersection design.

NCHRP Web-Only Document 150 is designed to serve as a companion resource document to a one-day training course on accessible pedestrian signals. For information on the training program, contact Stephan Parker of TRB at SAParker@nas.edu.

NCHRP Web-Only Document 150 is a reformatted edition of and replaces NCHRP Web-Only Document 117A: Accessible Pedestrian Signals: A Guide to Best Practice.

On July 20, 2011, TRB co-sponsored a web briefing or "webinar" that explored information about the project. As a part of the webinar, panelists provided information about how to host a free APS workshop offered through NCHRP. Details about the webinar can be found on our website.

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