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

Chapter: Appendix D - Prioritization Tool Instructions and Forms

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Suggested Citation:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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:"Appendix D - Prioritization Tool Instructions and Forms ." 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 D - 299 Appendix D: Prioritization Tool Instructions and Forms Purpose of the Prioritization Tool D-2 Understanding How Blind Pedestrians Cross at Signalized Intersections D-2 Overview of Prioritization Tool Worksheets D-4 Scoring System D-4 Intersection Worksheet Sketch D-5 Intersection Worksheet Variables D-5 Confi guration D-5 Signalization D-7 Transit Facilities within a Block (~ 1/8 mile) of Intersection — Any Leg D-9 Distance to Facility Providing Services to the Blind or Visually Impaired D-9 Distance to Major Pedestrian Attractions D-10 Crosswalk Worksheet Variables D-10 Crosswalk Width D-10 Speed Limit (street being crossed) D-10 Approach/Crosswalk Geometrics D-11 Pedestrian Signal Control D-14 Vehicle Signal Control D-16 Off -Peak Traffi c Presence D-19 Distance to Alternative APS Crossing D-20 Pedestrian Pushbutton Location (either corner) D-20 Requests for APS D-21 Blank Prioritization Tool Worksheets D-22 Examples of Completed Prioritization Tool Worksheets D-27 References D-34

D - 300 Appendix D: Prioritization Tool Instructions and Forms Purpose of the Prioritization Tool Municipalities responsible for the installation and operation of traffi c signals are often required to make decisions about the use of accessible pedestrian signals. In many cases, there is a need to prioritize existing signalized intersections for APS installations. Two such cases include: 1) where the number of requests exceeds the funding available in a given fi scal year, and 2) where transition plans for making intersections accessible are being completed and decisions must be made about the order of installations. Th is prioritization tool provides practitioners with the means to take observable characteristics of a pedestrian crosswalk and produce a score that refl ects the relative crossing diffi culty for pedestrians who are blind or visually impaired. Th is scoring system enables a prioritization of APS installations within a jurisdiction. Th e information regarding prioritizing intersections for installation of APS is not intended for application to new or reconstructed intersections. In new construction or reconstruction projects, it is appropriate to consider the Draft PROWAG as the best guidance available at this time. Th is guidance states that in new construction, APS should be installed wherever pedestrian signals are installed. Understanding How Blind Pedestrians Cross at Signalized Intersections Before discussing how intersection and crosswalk characteristics aff ect the travel of blind pedestrians, it is important to understand how blind and low vision pedestrians travel. Th is section gives an overview of this issue. At any given time, people who are blind or visually impaired can travel and cross streets using a human guide, using a long, white cane to identify and avoid obstacles, using a dog guide, using special optical or electronic aids, or using no additional aid. Whatever aid is used, street crossing is comprised of a number of tasks. 1) Locating the Street — First, pedestrians who are blind must determine when they reach a street. Th is is typically accomplished using a combination of cues, including the curb or slope of the ramp, traffi c sounds and detectable warnings. 2) Street Recognition — Next, blind pedestrians recognize or determine which street they have come to. Th is information is only occasionally provided in any accessible format, so pedestrians who are visually impaired develop a mental map and keep track of where they are within that map, usually by counting blocks and street crossings. Assistance may be sought from other pedestrians. 3) Intersection Assessment — Next, pedestrians who are blind obtain critical information about intersection geometry, including the location of the crosswalk, the

Accessible Pedestrian Signals: A Guide to Best Practice D - 301 direction of the opposite corner, the number of intersecting streets, the width of the street to be crossed, and whether there are any islands or medians in the crosswalk. Vehicular sounds, where there is a stream of traffi c on each street at the intersection, are used to infer intersection geometry. Pedestrians with visual impairments also need to identify the type of traffi c control system at an intersection. Th is may be determined by listening to traffi c patterns through several light cycles, and searching the sidewalk area for poles with pushbuttons. However, it has become diffi cult or impossible to determine the type of traffi c control at many intersections by listening. Th e inability to determine whether a crosswalk is pedestrian actuated may result in failure to use pedestrian push buttons and crossing at times other than the pedestrian phase. 4) Cross the Roadway — After determining the geometry of the intersection, aligning to face towards the destination curb, determining that the intersection is signalized, and having pushed a button (where necessary), pedestrians who are blind must recognize the onset of the walk interval. In the most common technique utilized for crossing at signalized intersections, pedestrians who are blind begin to cross the street when there is a surge of through traffi c on the closest side of the street parallel to their direction of travel. Once pedestrians who are blind have begun to cross the street, they must maintain a heading toward the opposite corner. Turning traffi c can make it diffi cult to establish a correct initial heading, and in the absence of traffi c on the parallel street, pedestrians who are blind may veer toward or away from the intersection. Optimal crossing conditions occur when crossing right angle signalized intersections with a moderate but steady fl ow of traffi c through the intersection on each leg with a minimum of turning movements. Pedestrian actuation requires blind pedestrians to locate and push a pushbutton, then cross on the next pedestrian phase to be assured of having enough time to cross. Blind pedestrians have three types of problems at these locations: 1) Th ey cannot wait through a light cycle to assess and refi ne their heading by listening to vehicular trajectories, before crossing at the next pedestrian phase because they have to locate and push the button again (and re- establish their heading). 2) At a location with little vehicular traffi c, even if pedestrians who are blind know there is a pushbutton and use it, they may not be able to detect the onset of the walk interval if there is no through traffi c on the street parallel to their crossing. 3) Blind pedestrians may not be aware that there is a pushbutton and/or they may be unable to locate the pushbutton. In addition, some locations do not include a pedestrian phase, and at times when vehicular volume is low, there may not be enough time to cross the street. In the past twenty years, signifi cant changes in intersection geometry, signalization, driver behavior, and the technology of automobiles have aff ected the ability of blind travelers in the United States to obtain the information they need to cross streets independently and safely. Traffi c clearing the intersection also commonly overlaps

D - 302 Appendix D: Prioritization Tool Instructions and Forms the pedestrian phase by as many seconds as the duration of the walk interval. In such cases, blind pedestrians will fi rst perceive the pedestrian phase, and initiate crossing, after the onset of the pedestrian change interval. Th ese changes have increased the requests for APS by blind pedestrians. Municipalities and states need a documented procedure to respond to such requests as required by the program access requirements of the Americans with Disabilities Act. Overview of Prioritization Tool Worksheets Th e prioritization tool includes three separate worksheets that should be used for rating each intersection (blank forms included on pages D-21 through D-24). Th e fi rst worksheet is the Intersection Worksheet and is used for describing characteristics of the intersection as a whole, including space for a sketch of the intersection. Th e second worksheet is the Crosswalk Worksheet and is used for describing the features associated with each crosswalk at the intersection. A separate crosswalk worksheet should be completed for each crosswalk at the intersection. Each of these forms includes variables that either provide an assessment of level of diffi culty that may be present for pedestrians who are blind or provide an indicator of the level of pedestrian activity in the vicinity of the intersection. Th e variables are further defi ned in the latter sections of this document. Each form also includes space for additional comments to be provided. Finally, a Supplemental Form is provided for those locations where more drawings or additional notes may be required. Scoring System Th e APS Prioritization Tool provides a score for an individual crosswalk. Higher scores indicate a greater priority for APS installation. Lower scores indicate a lower priority for APS. Th ere is no particular score that indicates whether APS should be installed or not. Th e scores are intended to provide a relative prioritization scheme among a group of crosswalks. Th e system of scoring is based on the premise that it is the individual crosswalk that is critical, as opposed to the intersection as a whole. Th erefore, priorities for installation should be established on the basis of individual crosswalks, rather than complete intersections. Jurisdictions may choose to install APS at all crosswalks of an intersection when installing them at one crosswalk. However, the intent is to rank and consider each crosswalk separately. If a scoring system were used that is based on the combined score of all crosswalks at an intersection, a very diffi cult crosswalk for blind pedestrians combined with three crosswalks that are relatively easy could result in low ranking for the intersection as a whole. Such an intersection-based system could result in critical crosswalks being missed on a priority list. Th e total score for a crosswalk is calculated as the sum of the individual crosswalk score and the intersection score. Th e Intersection Worksheet includes the Intersection

Accessible Pedestrian Signals: A Guide to Best Practice D - 303 Worksheet Score in the bottom right corner. Th e total crosswalk scores are found in the bottom right corner of each of the Crosswalk Worksheets. Each Crosswalk Worksheet includes the Crosswalk Worksheet Score and the Intersection Worksheet Score (transferred from the Intersection Worksheet), which are added together to get the resulting Total Crosswalk Score. Th e Total Crosswalk Scores can be listed on the Cover Sheet for quick reference. Intersection Worksheet Sketch Th e Intersection Worksheet includes space for a simple sketch of the intersection being rated. At a minimum, the sketch should capture the following: 1) Crosswalk location and orientation, including skew and any change in direction (each one should be labeled (e.g., A, B, C, and D) for correct reference to the Crosswalk Worksheets. 2) Location of pushbuttons and other signal features. 3) Geometrics, such as islands and lane confi guration. Additional sketches and notes, as required, should be recorded on the Supplemental Worksheet. Intersection Worksheet Variables CONFIGURATION Pedestrians who are blind or visually impaired use the sound of traffi c moving beside them as an alignment cue and as a cue for determining when the traffi c signal changes. Th erefore, the number of approaches to an intersection and the geometric confi guration aff ects the diffi culty of crossing. A standard 4-leg intersection with perpendicular approaches is the easiest confi guration. If those approaches are off set while still controlled by the same signal, the crossing becomes more diffi cult as it becomes harder to recognize the parallel traffi c fl ow from the minor street. T-intersections are more diffi cult for similar reasons. Crossing the top of a T-intersection can be problematic due to the fact that the simultaneous traffi c fl ow is from the stem of the T and is either turning right or left. Intersections with more than 4 legs can also result in ambiguous traffi c fl ow cues for pedestrians with visual impairments. Mid-block signalized locations are most diffi cult for blind pedestrians because there is no traffi c stream parallel to the crosswalk to provide an audible cue. Given this, signalized mid-block crosswalks receive the highest point value in the Confi guration category (14 points). Since completing the remainder of the worksheets for a mid- block crossing may prove confusing, the categories that apply to a mid-block crossing have been listed in Table 1 below.

D - 304 Appendix D: Prioritization Tool Instructions and Forms INTERSECTION WORKSHEET VARIABLE CAN APPLY TO MID-BLOCK CROSSING? Confi guration Yes Signalization Yes, Actuated Transit Facilities Yes Distance to Facilities for Visually Impaired Yes Distance to Major Ped Attraction Yes CROSSWALK WORKSHEET VARIABLE CAN APPLY TO MID-BLOCK CROSSING? Crosswalk width Yes Posted Speed Limit Yes Curb radius > 25 feet No Islands or medians Yes Transverse slope No Apex curb ramp No Channelized right turn island No Skewed crosswalk No Pushbutton actuation required Yes Non-concurrent WALK interval No Leading Pedestrian Interval No Timed for crossing to median island Yes RTOR permitted No Leading protected left turn No Protected right turn overlap No Channelized right turn under signal No Off -Peak Traffi c Presence Yes Pushbutton location Yes Requests for APS Yes SIGNALIZATION Th e sequence of phases at a signalized intersection and other features of the signal operation, such as interval lengths and actuation-only phases, aff ects the ability of a blind pedestrian to determine when it is appropriate to cross. Th is information is captured in two places. Th e Signalization variable captures information about the general signal operation that may aff ect the diffi culty of crossing any or all streets. Table 1. Applicable Variables for Mid-Block Crossings

Accessible Pedestrian Signals: A Guide to Best Practice D - 305 Th e Crosswalk Signalization variable on the crosswalk worksheet captures details about the signal operation that impact a particular crosswalk. Th e following signalization options are given on the form. Th e user should select the option that has the highest point value AND applies to the intersection of interest. For example, if an actuated intersection has an exclusive pedestrian phase, then the user should select only “exclusive pedestrian phase”, since that option has a higher point value than actuation. Pre-timed — Pre-timed signalized intersections are the easiest for a blind pedestrian to understand, since the phase sequence and intervals remain the same in every cycle. Actuated — Actuated signals are more diffi cult for blind pedestrians since the interval timing may change or phases may be skipped on each cycle. In addition, some actuated signals require the pedestrian to fi nd and push a pushbutton to obtain a WALK interval. Note: Th is intersection signalization variable is intended to capture actuation associated with vehicular traffi c. Pedestrian actuation is captured within the Crosswalk Signalization variable on the Crosswalk Worksheet. Split phasing (on either street) — Th e auditory cues of split phasing can provide confusing information. Split phasing on the street parallel to the crosswalk can lead a blind pedestrian to believe they have the WALK interval because the cross street traffi c is stopped and they hear a surge on the parallel street, not knowing that left- turning vehicles may be present. In the image on the left in Figure D-1, a pedestrian going north on the east crosswalk (bottom right corner) will have the WALK indication. A pedestrian going north on the west crosswalk (bottom left corner) will have DON’T WALK, since the northbound left turning traffi c has a protected turn. Without APS, if a blind pedestrian on the bottom left corner hears the northbound through traffi c, they might assume that they have the WALK indication and cross the street — presenting a potentially dangerous confl ict with northbound left-turning traffi c which has a protected turn. Split phasing on the street to be crossed can also be confusing in that the left-turning traffi c onto the parallel street may be mistaken for the parallel street traffi c surge. Th is variable does not include leading protected left turns; that signal feature is covered as a crosswalk-level variable. Exclusive pedestrian phase — An exclusive pedestrian phase forces all vehicular traffi c at an intersection to stop. It is much more diffi cult for a blind pedestrian to determine the onset of a WALK interval when there is no vehicular movement and thus no surge of traffi c. A lull in traffi c fl ow may be perceived as the onset of the WALK. However, a lull in traffi c may also be perceived as gaps in traffi c or changes between phases, rather than the onset of an exclusive pedestrian phase. Where RTOR is permitted in combination with exclusive pedestrian phasing, an intersection may never be quiet enough for pedestrians who are blind to be sure that the pedestrian interval has begun. If they cross at such intersections independently, they are likely to begin crossing well into the pedestrian clearance interval. Additional points should be added for RTOR (separate variable described below) when present.

D - 306 Appendix D: Prioritization Tool Instructions and Forms TRANSIT FACILITIES WITHIN A BLOCK (~ 1/8 MILE) OF INTERSECTION — ANY LEG Th e availability of transit facilities within close proximity to an intersection will increase the likelihood of blind pedestrians, as well as sighted pedestrians, crossing at that intersection. Th e probability increases as the number of stops and routes increases, with the greatest probability occurring when there is a major transfer facility present, such as a transit mall or rail station. Th e levels on the prioritization tool account for transit activity by recording the number of routes that have stops within a block of the intersection. A single route will most likely be on the major street of an intersection. Multiple routes may include multiple major-street routes or a combination of major- and minor-street routes. DISTANCE TO FACILITY PROVIDING SERVICES TO THE BLIND OR VISUALLY IMPAIRED Th e closer a facility for persons who are visually impaired is to an intersection, the more likely it is that pedestrians who are blind or visually impaired will need to cross at that intersection. Facilities that fall into this category include an adult rehabilitation center, library for the blind, residential school for the blind, offi ces of rehabilitation counselors, and other centers providing services for people who are blind or visually impaired. Figure D-1. Split Phase Illustration

Accessible Pedestrian Signals: A Guide to Best Practice D - 307 Knowing the locations of these facilities will be diffi cult for any transportation department without good communication with the blind community. It is the responsibility of the department and the blind community to maintain a working relationship with each other. Organizations such as regional associations for the blind would be able to inform the department of any new schools or facilities that provide services to persons who are blind or visually impaired. DISTANCE TO MAJOR PEDESTRIAN ATTRACTIONS Th e intent of this variable is to serve as a surrogate measure for pedestrian usage at the intersection without having to make pedestrian counts. Most agencies simply do not have such counts or the resources to acquire such. Major pedestrian attractions include, but are not limited to major shopping areas, major cultural venues, educational campuses, recreational areas and medical facilities. Th e designation of “major attraction” will depend on the characteristics of the municipality. Th e idea behind this variable is that higher pedestrian activity will increase the chance of blind or visually impaired pedestrians crossing at the intersection, which would increase the need for APS. Crosswalk Worksheet Variables CROSSWALK WIDTH Crosswalk width is defi ned as the curb-to-curb measurement taken at the midpoint of the crosswalk. A longer crosswalk increases the potential that pedestrians who are blind will veer out of the crosswalk, as well as making it more critical for the blind pedestrian to start as quickly as possible after the onset of the WALK interval. In the case of a channelized right turn island, the crosswalk length should be measured from curb to island (Figure D-2). Widths less than 40 ft receive no points. Figure D-2. Diagram A demonstrates the crosswalk width measurement of a standard crosswalk. Diagram B demonstrates crosswalk width measurement of a crosswalk at a channelized right turn lane.

D - 308 Appendix D: Prioritization Tool Instructions and Forms SPEED LIMIT (STREET BEING CROSSED) Th e higher the speed of the vehicles on the street being crossed, the lower the probability of avoiding an incident should a visually impaired pedestrian mistakenly step into the street and the higher the probability of injury should a crash occur. Since operating speeds are not always available, the posted speed limit can be used as a surrogate measure. Speed limits of 20 mph and lower receive no points. APPROACH/CROSSWALK GEOMETRICS Th ere are several geometric factors at a crosswalk that can negatively impact upon the ability of a blind pedestrian to safely cross the street. Each of the factors on the form under this heading is defi ned below. Curb radius > 25 ft (either corner) It is more diffi cult to establish an initial correct heading where curb radii are wide. Incorrect headings can result in pedestrians who are blind walking toward the center of the intersection. Islands or medians Raised or painted crossing islands and medians can confuse blind pedestrians during their crossing, slow or delay their crossing, aff ect crossing alignment, and generally make the crossing more diffi cult. Points should be added for any median or island, painted, raised, or cut-through, that crosses the crosswalk, particularly when the crosswalk changes direction at the island. Islands that are present for channelized right turns are taken into account in the “Channelized right turn island” factor. Transverse slope on crosswalk (cross slope) Crosswalks with a severe cross slope (> 5 %) can lead to veering toward the downhill side by a blind pedestrian during the crossing. Depending on the direction of the cross slope, they could either veer into the intersection or into the approach leg. A beaconing APS may counter this tendency to veer. Apex (diagonal) curb ramp (either corner) Where the slope of the curb ramp is not aligned with the direction of travel on the crosswalk, blind pedestrians may misalign for the crossing and walk into the fl ow of parallel traffi c. Th is misalignment most commonly occurs with “apex” curb ramp confi gurations (Figure D-3). Th is apex confi guration occurs when the corner only has one ramp that points toward the center of the intersection, usually for the purpose of serving two perpendicular crosswalks. If the corner has two ramps that each serves one crosswalk, the corner has a perpendicular ramp confi guration (Figure D-4).

Accessible Pedestrian Signals: A Guide to Best Practice D - 309 Channelized right-turn lane island Crossings at a channelized right-turn lane normally require the pedestrian to cross to the island in one direction, reorient themselves, and then complete the crossing in a diff erent direction (see Figure D-5). Th is direction change is potentially confusing to blind pedestrians. Most of the right-turn lanes where such islands are present are unsignalized. Th erefore, an APS will not be installed for the right-turn lane crossing unless a traffi c signal is being added. Th e APS installation that should be considered at these locations is on island for the crosswalks that cross the through travel lanes. Th e locator tones, as well as the WALK interval tones and speech messages, on an APS device under these conditions may assist the visually-impaired pedestrian with the reorientation that is required to fi nd the correct crosswalk. Note: Islands and medians separating traffi c lanes in the middle of the road are taken into account by the “Islands or medians” variable. If the right-turn lane is signalized, refer to the “Channelized right turn lane under signal control” variable. Figure D-3. Photo and sketch of an apex ramp confi guration Figure D-4. Photo and sketch of a perpendicular ramp confi guration

D - 310 Appendix D: Prioritization Tool Instructions and Forms Skewed crosswalk If the direction of travel on a crosswalk is diff erent from the direction of travel on the approaching sidewalk (is skewed), the consequence of failure to establish a heading toward the opposite corner is often that blind pedestrians will walk toward the center of the intersection and into the path of parallel traffi c. Th e degree of skew can vary from crosswalk to crosswalk. Skew, in this case, is not defi ned by the angle at which the streets intersect. If a blind pedestrian walking a straight line from the approaching sidewalk is headed toward parallel traffi c lanes, the crosswalk is skewed (see crosswalk A in Figure D-6). If the blind pedestrian would end up deviating from the crosswalk but would still arrive at the opposite corner, the crosswalk is not defi ned as skewed for this rating tool (see crosswalk B in Figure D-6). Figure D-5. Crosswalks at a channelized turn island Figure D-6. Crosswalk A is defi ned as skewed because a pedestrian following the sidewalk line is headed toward the parallel traffi c Crosswalk B is not skewed because a pedestrian following the sidewalk line is headed toward the opposite corner.

Accessible Pedestrian Signals: A Guide to Best Practice D - 311 Skewing can also occur at crosswalks where the pedestrian walk signal only gives enough time for the pedestrian to reach a median. In this case, the blind pedestrian must be able to fi nd the median to wait for the next signal cycle. A skewed or bent crosswalk may cause the pedestrian to miss the median. In this situation, the crosswalk is defi ned as skewed (Figure D-7). Determination of skew should not consider the island of a channelized right turn (Figure D-5). Although crossing from curb to curb may involve a crooked path due to a direction change at the island, this disadvantage is already accounted for in the fi elds relating to channelized turn islands. PEDESTRIAN SIGNAL CONTROL Th e ability of a pedestrian who is visually impaired to safely cross at a crosswalk can be impacted by the WALK interval timing and other pedestrian signal control features. Each of these factors is defi ned below. Push button actuation required for WALK At unfamiliar intersections, pedestrians who are blind have no way to know pedestrian actuation is required unless there is an APS with a locator tone. Th erefore pedestrians who are blind are unlikely to use pushbuttons at unfamiliar intersections and are more likely to cross relying only on the cue of traffi c surge, whether or not it corresponds to the onset of the walk interval. Even if the parallel traffi c surge is interpreted correctly, the green phase timing may not be suffi cient to allow a pedestrian to safely cross the street. Th e problem is compounded when the pushbutton is not right beside the probable location of a pedestrian who is waiting to cross; this may require pedestrians who are blind or visually impaired to repeatedly leave their chosen starting location and heading and push the button again, and then return to their chosen starting location and re-establish their heading. Figure D-7. This crosswalk is defi ned as skewed because it is timed for median crossing (two-stage) and a blind pedestrian might miss the median due to the bent crosswalk.

D - 312 Appendix D: Prioritization Tool Instructions and Forms Non-concurrent WALK interval Some signal timing plans at multi-leg intersections display the pedestrian WALK signal at a diff erent time than the green phase for adjacent parallel traffi c (Figure D-8). Pedestrians who are blind or visually impaired will typically assume that the WALK interval will begin with the onset of through traffi c on the parallel street. Without an APS, they will not know the appropriate time to cross at such locations. Leading Pedestrian Interval — LPI (with parallel street green) Th e LPI permits pedestrians parallel to a traffi c stream to move prior to the vehicles receiving a green signal, with a goal of allowing pedestrians to “claim” the crosswalk space prior to vehicles that may be turning right (Figure D-9). Unfortunately, this treatment creates a scenario in which blind pedestrians are unable to detect the beginning of the walk interval if there is no audible indication. Subsequently, they may begin crossing only when the parallel traffi c starts, which may be too late in the pedestrian phase and at a time when drivers are not expecting them. Timed for crossing to median island On wide streets with medians or crossing islands, blind pedestrians cannot easily determine whether the WALK signal is intended to allow them to cross the entire street or only to the mid-point. Without an APS providing an audible cue at the median, blind pedestrians are unable to recognize that they must stop there, which may place them in a high-risk situation. Th e MUTCD states: “Where the pedestrian clearance time is suffi cient only for crossing from the curb or shoulder to a median of suffi cient width for pedestrians to wait, additional measures should be considered, such as median- mounted pedestrian signals or additional signing.” (MUTCD 2003) Figure D-8. Pedestrian crosswalk with non-concurrent WALK interval

Accessible Pedestrian Signals: A Guide to Best Practice D - 313 Vehicle Signal Control Th e types of signal phases available for vehicle traffi c can greatly impact upon the ability of the pedestrian who is visually impaired to understand the audible cues from the traffi c surges of various movements and make correct decisions about when it is appropriate to cross the street. Each type of signal phasing that may lead to this ambiguity is defi ned below. Right-Turn-On-Red (RTOR) permitted (on parallel street) Th e allowance of RTOR on the parallel street may create a false audible cue for the blind pedestrian (Figure D-10). Vehicles turning right after stopping may be interpreted as indicating the onset of the parallel green phase, and pedestrians who are blind or visually impaired may begin to cross the street at the wrong time. RTOR vehicles also make it harder to audibly recognize the onset of the parallel traffi c movement. Figure D-9. Leading Pedestrian Interval (source: Insurance Institute for Highway Safety) Figure D-10. Right turns on red can mislead blind pedestrians

D - 314 Appendix D: Prioritization Tool Instructions and Forms Th e allowance of RTOR during an exclusive pedestrian phase also sends mixed signals. If vehicles are turning, blind pedestrians may not be aware that they have a WALK interval. If they do recognize it, there may be a delayed initiation of crossing which means they may not begin crossing on the WALK interval and may still be in the street during the DONT WALK interval. Leading protected left-turn phase (on parallel street) It can be diffi cult for a blind pedestrian to audibly distinguish between the surge of traffi c at the beginning of a protected left-turn phase and the beginning of the through traffi c phase (Figure D-11). Th e moving cars of the leading left-turn phase may also mask the sounds of the parallel through traffi c beginning to move, particularly if the protected left-turn interval is followed by a permissive left-turn interval. Note: Points are not given for lagging left-turn phases, which are much better for a blind pedestrian. With a lagging left-turn interval, the through traffi c on the parallel street is the fi rst vehicular maneuver after traffi c stops on the cross street. Th e onset of the WALK interval usually occurs at the same time and allows all pedestrians, including blind pedestrians to initiate the crossing. Th e pedestrians are then typically clear of the intersection by the time the lagging left-turn interval begins. Protected right-turn-only phase (on parallel street) Th e surge of traffi c by right-turning vehicles using a protected right-turn phase may be incorrectly interpreted as the beginning of the parallel through traffi c surge and the simultaneous onset of the WALK interval (Figure D-12). Channelized right-turn lane under signal control Figure D-11. Leading protected left turns can mislead blind pedestrians

Accessible Pedestrian Signals: A Guide to Best Practice D - 315 Turning vehicles at channelized turns are typically under yield control. Th ey must stop only if there is traffi c approaching intersection the cross street, or if a pedestrian is in the crosswalk. However, at some channelized right-turn lanes, vehicles are controlled by a signal that prohibits turns if the signal is red (Figure D-13). Without an audible indication, a blind pedestrian will not know that traffi c at the channelized turn lane is under signal control and may attempt to cross when the traffi c has a green signal. Th is confusion of priorities may lead to an unsafe crossing. Note: Th e point values for this factor are for the “signalization” component only. A channelized right-turn lane that is signalized will also receive points under “Channelized right turn island”. Figure D-12. Protected right turn phase can mislead blind pedestrians Figure D-13. Channelized turn lane under signal control

D - 316 Appendix D: Prioritization Tool Instructions and Forms OFF-PEAK TRAFFIC PRESENCE Traffi c fl ow that is very light or erratic (which most often occurs in off -peak periods) makes it diffi cult to use traffi c sound to recognize signal changes. In such cases, audible signals can help to determine the onset of the walk interval. While many municipalities may have turning movement counts or average daily traffi c counts, it is not a simple or uniform process to translate these numbers into a meaningful measure for assessing off -peak traffi c presence. Instead, this variable is scored on the basis of the proportion of time that at least two vehicles are present at the beginning of a green phase in through lanes that are parallel to the path of the pedestrian. Note that traffi c presence in this category refers to traffi c that is parallel to the crosswalk and passes straight through the intersection. If there is no through traffi c at the intersection (no lanes continuing straight), there is no reliable traffi c available for the blind pedestrian to use as a cue that the walk interval has begun, and the crosswalk would get a rating of “None” and receive the maximum number of points. An example of such a confi guration is a T-intersection (Figure D-14). Noting the number of signal cycles with 2 or more through vehicles over 5 to 10 cycles during the off -peak should be suffi cient for determining the percentage for scoring this variable. Th e levels provided on the worksheet refl ect the results that may be acquired in such an exercise. DISTANCE TO ALTERNATIVE APS CROSSING If there is another signalized crosswalk with APS in close proximity to the intersection being rated, the intersection should receive a lower score (lower priority for APS) than a similar intersection where there is no nearby crossing alternative. Figure D-14. Crosswalks A and B, across top of the T, at a T-intersection, have no parallel through traffi c. In contrast, Crosswalk C has parallel through traffi c.

Accessible Pedestrian Signals: A Guide to Best Practice D - 317 If an alternative accessible crossing is present and scored as such, care must be taken to ensure that the alternative crossing meets the need of the blind traveler by getting them to/from the destination. Just because a crossing is close, it may not always be in a location that helps get the person to their destination. A local Orientation & Mobility Specialist or a pedestrian who has requested an APS can assist with making this determination. PEDESTRIAN PUSHBUTTON LOCATION (EITHER CORNER) Section 4E.09 of the MUTCD provides guidance on where pedestrian pushbuttons with APS should be located as follows: a) 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; b) Within 1.5 m (5 ft) of the crosswalk extended; c) Within 3 m (10 ft) of the edge of the curb, shoulder, or pavement; and d) Parallel to the crosswalk to be used. (MUTCD 2003) Th e Crosswalk Worksheet provides for points to be added if the location of pedestrian push buttons on either side of a crosswalk does not meet either B or C above. In essence, this variable will give an intersection with poorly located pushbuttons a higher priority for the installation of APS over an intersection with properly located pushbuttons (assuming all other characteristics of the two intersections are the same). Poorly located pushbuttons create much greater diffi culty for blind pedestrians in terms of being easily accessible, being positioned in a manner to provide alignment cues, and being located close enough to the curb to be pushed and then cross on the same cycle. REQUESTS FOR APS Requests for an APS may come from a pedestrian who is visually impaired or from an Orientation and Mobility professional. Th ese requests are usually very specifi c – the individual needs to travel from their home to their workplace and needs to cross this street using this crosswalk. Such requests should increase the priority for APS.

D - 318 Appendix D: Prioritization Tool Instructions and Forms Blank Prioritization Tool Worksheets On the following pages are blank forms that may be reproduced for use in the fi eld when evaluating intersections and crosswalks. Th ere are three separate forms to be used at all intersections — an Intersection Worksheet, Crosswalk Worksheet, and Supplemental Form — as well as a cover sheet for easy reference of the crosswalk scores.

Accessible Pedestrian Signals: A Guide to Best Practice D - 319 Figure D-15. Cover Sheet of APS Prioritization Tool

D - 320 Appendix D: Prioritization Tool Instructions and Forms Figure D-16. Intersection Worksheet of APS Prioritization Tool

Accessible Pedestrian Signals: A Guide to Best Practice D - 321 Figure D-17. Crosswalk Worksheet of APS Prioritization Tool

D - 322 Appendix D: Prioritization Tool Instructions and Forms Figure D-18. Supplemental Worksheet of APS Prioritization Tool

Accessible Pedestrian Signals: A Guide to Best Practice D - 323 Examples of Completed Prioritization Tool Worksheets Th e following two examples show how the Prioritization Tool would be used to rate two crosswalks. Th e fi rst example is a crosswalk that would be relatively easier for pedestrians who are blind or visually impaired. Th e second example is a crosswalk that would be relatively diffi cult. EXAMPLE CROSSWALK #1 Th is example uses the APS Prioritization Tool to rate a crosswalk at an intersection in a dense urban area. Both streets of the intersection are fairly narrow and have 35 mph speed limits. Th e signal is pretimed. Figure 5-1 shows an overhead view of the intersection, with the crosswalk of interest outlined. Th e fi rst worksheet deals with the intersection characteristics (Figure D-20). Th e total intersection score was zero, since the intersection was a simple 4-legged confi guration with a pretimed signal and was not located near transit facilities, facilities for the visually impaired, or major pedestrian attractions. Figure D-19. Overhead view of Example Crosswalk #1 (Google Earth © 2005)

D - 324 Appendix D: Prioritization Tool Instructions and Forms Th e second worksheet deals with the crosswalk (Figure D-21). Points were given for the following reasons: • Th e crosswalk width is 50 feet. Th e worksheet range of 40-59 feet earns one point. • Th e posted speed limit on Prospect (the street being crossed) is 35 mph. Th is earns three points. • Th e traffi c on Broadway (the parallel street) is constant, thereby giving constant audible cues for the pedestrian. Th is variable earns only one point. • Th ere is another APS-equipped crosswalk within one-quarter mile. Th us, the crosswalk being rated earns 2 points in this category. Th ere are no characteristics of this crosswalk that would qualify under the sections for “Approach/Crosswalk Geometrics,” “Pedestrian Signal Control,” or “Vehicle Signal Control.” In addition, the pushbutton poles are located close to the curb and within the crosswalk lines extended and there have been no requests for APS at this crosswalk; both receive zero points on the prioritization scheme. Figure D-20. Intersection Worksheet for Example Crosswalk #1

Accessible Pedestrian Signals: A Guide to Best Practice D - 325 Th e crosswalk worksheet score is 7 points. When added to the intersection score of zero points, this yields a total crosswalk score of 7 points. In practice, this score of 7 points would be compared to other crosswalks under consideration for APS installations. Th ose crosswalks with the highest scores would have the highest priority for APS. EXAMPLE CROSSWALK #2 Th is example rates a crosswalk at a large intersection of a major arterial and a minor side street. Th e crosswalk of interest is on the east leg (highlighted in Figure D-22; shown at street level in Figure D-23). Figure D-21. Crosswalk Worksheet for Example Crosswalk #1

D - 326 Appendix D: Prioritization Tool Instructions and Forms Figure D-22. Overhead view of Example Crosswalk #2 (Google Earth © 2005) Figure D-23. Street view of Example Crosswalk #2

Accessible Pedestrian Signals: A Guide to Best Practice D - 327 Th e fi rst worksheet deals with the intersection characteristics (Figure D-24). Points were given for the following reasons: • Th e signal is actuated but also uses split phasing, which is a higher point value than actuation, so the intersection gets the six points for split phasing. Split phasing is a less commonly used signal design, and the typically heavy turning movements make it harder to eff ectively use the traffi c movement cue to determine signal changes. APS would provide a defi nitive cue to the onset of the WALK interval for pedestrians who are unable to see the pedestrian signal. • Th ere is a single bus route on the main street, which earns another point. Th e presence of public transit increases the likelihood that visually impaired pedestrians will travel at this intersection, thereby increasing the priority for APS. Th ere are no facilities specifi cally providing services for individuals who are visually impaired or major pedestrian attractors within one-half mile, so no points are given for those categories. Th e total intersection score is seven points. Figure D-24. Intersection Worksheet for Example Crosswalk #2

D - 328 Appendix D: Prioritization Tool Instructions and Forms Th e second worksheet deals with the crosswalk (Figure D-25). Points were given for the following reasons: • Th e crosswalk width of 110 feet and speed limit of 45 mph on the main street earn the crosswalk four and fi ve points, respectively. Wider crosswalks and faster traffi c increase the crossing diffi culty and risk to visually impaired pedestrians, and APS may help expedite their crossing. • Th e curb radius on one of the corners bordering the crosswalk is greater than 25 feet, so one point is given in the geometrics category. Larger curb radii create orientation problems for visually impaired pedestrians that may be decreased with the use of an APS. • Th e signal requires push button actuation for the pedestrian WALK signal, so four points are given for the pedestrian signalization category. An APS locator tone would help a pedestrian who is visually impaired recognize that there is a pushbutton at that crosswalk and help in locating the pushbutton. • Right-turn-on-red (RTOR) is permitted at the crosswalk, so two points are given in the vehicle signal control category. RTOR may produce misleading traffi c cues, and an APS would provide a defi nitive cue of the appropriate time to cross. • During off -peak hours, there was enough parallel traffi c to provide audible cues (2 or more vehicles per cycle) about 75% of the time. Th is earns two points. • Th ere is not an alternative APS crosswalk within one-half mile, so four points are given towards the prioritization of an APS installation at this crosswalk. • Th e pedestrian push button at one end of the crosswalk is located more than 10 feet from the curb, which is contrary to the recommendations in Section 4E.09 of the MUTCD. Th ree points are given for this drawback, since a correctly installed APS would position the push button closer to the curb which facilitates orientation alignment for blind and visually impaired pedestrians. Th e crosswalk worksheet score is 25 points. When added to the intersection score of seven points, this yields a total crosswalk score of 32 points. In practice, this score of 32 points would be compared to other crosswalks under consideration for APS installations. Th ose crosswalks with the highest scores would have the highest priority for APS.

Accessible Pedestrian Signals: A Guide to Best Practice D - 329 Figure D-25. Crosswalk Worksheet for Example Crosswalk #2

D - 330 Appendix D: Prioritization Tool Instructions and Forms References Manual on Uniform Traffi c Control Devices, 2003 Edition, (with Revision No. 1 incorporated), Federal Highway Administration, Washington, DC, November 2004.

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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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