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

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Accessible Pedestrian Signals: A Guide to Best Practice 13 Chapter 2: Travel by Pedestrians Who are Blind or Who Have Low Vision CHAPTER SUMMARY Th is chapter provides demographic information about individuals who are blind or who have low vision, and information about types of vision loss. Travel techniques are explained and the eff ect of changes in traffi c control and signalization on the travel of pedestrians who are blind or visually impaired is discussed. CHAPTER CONTENTS Blindness and Vision Loss 14 Travel Tools and Techniques of People Who are Blind or Who Have Low Vision 18 How People Who are Blind or Visually Impaired Cross Streets 21 Changes in the Travel Environment 24

14 Chapter 2: Travel by Pedestrians Who are Blind or Who Have Low Vision Blindness and Vision Loss DEFINITIONS Visual impairment: a functional limitation in seeing, including both those with: • “non-severe limitation” (“diffi culty seeing words and letters”) and • those with “severe limitation” (“unable to see words and letters”). Legal blindness: a level of visual impairment that has been defi ned by law to determine eligibility for benefi ts. Legal blindness refers to central visual acuity of 20/200 or less in the better eye with the best possible correction, as measured on a Snellen vision chart, or a visual fi eld of 20 degrees or less. Vision correctable to 20/20 with at least 180-degree fi eld is considered ‘normal vision’. A simplifi ed example of visual acuity is that a person who is legally blind with 20/200 vision sees at approximately 20 feet what a person with 20/20 vision sees at 200 feet. A person with a visual fi eld of 20 degrees or less is able to see no more than a 20-degree fi eld without scanning. TYPES OF VISION LOSS General types of vision loss • Reduced acuity • Restricted fi elds (central or peripheral) • Combination of reduced acuity and restricted fi elds • Total blindness or light perception only Reduced acuity can refer to a large range of functional vision from vision tested as 20/20 to totally blind. Lighting and contrast aff ect functional vision and are not refl ected in the clinical measurements. Th e general category of restricted fi elds can be further divided into central fi eld loss and peripheral fi eld loss.

Accessible Pedestrian Signals: A Guide to Best Practice 15 REDUCED ACUITY Th e picture below represents a street crossing as it might be seen by a person with general reduced visual acuity. An overall loss of acuity, sensitivity to glare, and loss of contrast sensitivity is common in the elderly population. CENTRAL FIELD LOSS Individuals with a central fi eld loss usually will have diffi culty seeing pedestrian signals, some signs, and details directly in front of them. Central fi eld loss is typical of macular degeneration, the leading cause of blindness in those over 60. Figure 2-1. A street crossing as might be seen by a person with general reduced visual acuity Figure 2-2. The same street crossing as might be seen by a person with central fi eld loss

16 Chapter 2: Travel by Pedestrians Who are Blind or Who Have Low Vision PERIPHERAL FIELD LOSS Individuals with peripheral fi eld loss, sometimes referred to as tunnel vision, may see details directly in front of them clearly, but have diffi culty with objects and signs off to the side. In addition, depth perception is often impaired. Glaucoma and retinitis pigmentosa are the main causes of peripheral fi eld loss. DECREASE IN ATTENTIONAL FIELD Research by Brabyn, Haegerström-Portnoy, Schneck, and Lott (Brabyn et al., 2000), demonstrated that over age 60-65 the prevalence of problems detecting objects in the peripheral visual fi eld increases dramatically. Th is is known as a decrease in attentional fi eld, and it may be present with or without other types of visual impairment. By age 90, 40% of people have an attentional fi eld of less than 10 degrees left and right. Th us, if they are looking at a pedestrian signal head, they are unlikely to be visually aware of vehicles that may be turning across their path of travel, until it is too late to take appropriate action. TOTAL BLINDNESS OR LIGHT PERCEPTION Individuals who are considered totally blind usually cannot see any diff erence in light and dark. Individuals who have light perception may be able to tell if it is dark or light and the direction of a bright light source, but do not have vision that is useable for discerning objects or the travel path. Figure 2-3. The same street crossing as might be seen by a person with peripheral fi eld loss

Accessible Pedestrian Signals: A Guide to Best Practice 17 PREVALENCE OF BLINDNESS Diff erent sources provide diff erent estimates of the prevalence of blindness in the U.S. Th ere is no registry of individuals with vision loss in the U.S. and diff erent methodologies are used to derive these estimates. Adams, Hendershot, & Marano (1999) estimate that some degree of vision impairment aff ects 8.3 million (3.1%) Americans of all ages. Centers for Disease Control and Prevention (CDC) states that more than one million Americans are legally blind and 12 million are visually impaired. It is projected that the number of blind and visually impaired people will double by 2030 (CDC, 2003). Th e Lighthouse National Survey reports that 8.7 million (9%) Americans age 45 and older report a severe vision impairment, defi ned as an inability to recognize a friend at arm’s length even when wearing corrective lenses; an inability to read ordinary newspaper print with corrective lenses; poor or very poor vision even when wearing corrective lenses; or blindness in both eyes. (Th e Lighthouse Inc., 1995). A Health and Activity Limitations post-censal survey (HALS) by Statistics Canada reported that 635,000 Canadians identifi ed themselves as having a “seeing disability” (HALS, 1995). Of the 635,000 Canadians with a seeing disability: • 511,000 were adults living in households • 94,000 were adults living in institutions • 30,000 of these were children aged 14 years and under AREA OF RESIDENCE Of people with vision impairments, 33% live in cities, 37% live in suburbs, 28% live in non-metropolitan areas (e.g., small towns) and 1% live in farm areas (Schmeidler & Halfmann, 1998). In comparison to the general population, persons who are visually impaired are somewhat under-represented in the suburbs (i.e., 48% of general population live in suburbs vs. 37% of visually impaired) and over-represented in cities.

18 Chapter 2: Travel by Pedestrians Who are Blind or Who Have Low Vision Travel Tools and Techniques of People Who are Blind or Who Have Low Vision SEVERAL CHOICES People who are blind or visually impaired make choices when it comes to traveling. At any given time, they can travel using a human guide, which involves holding onto someone’s arm; using a long, white cane to identify and avoid obstacles or elevation changes; using a dog guide; using special optical or electronic aids; or using no additional aid. Th e choice of tools depends on the extent and nature of visual impairment, personal preference, lighting, and familiarity with the area. In order to travel independently, people with visual impairments use whatever vision they have, auditory and tactual information, and any gathered knowledge of an area to keep track of their location and make travel decisions. HUMAN GUIDE (SOMETIMES REFERRED TO AS SIGHTED GUIDE) At one time or another, most people who are blind will make use of the human guide technique, in which a person with sight serves as a guide to a person who is blind or visually impaired. LONG WHITE CANE Many individuals who are blind or visually impaired use a long white cane as a mobility device. In the most common technique, the cane is extended and swung back and forth across their body in rhythm with their steps to provide information about the environment directly in front of them, such as elevation changes or obstacles. In another technique often used by people with low vision, the cane is held diagonally across their body, with the tip about an inch above the ground. When those individuals are unsure about what they are seeing, they usually check the object or sidewalk surface with their cane. DOG GUIDE Dog guides are carefully trained service animals used as travel tools by approximately 2% of people who are blind. Th e dog responds to the commands of its handler, such as right, left and forward. Th e dog guides the handler around obstacles and stops at curbs or stairs. However, the handler must know where they are going and make decisions about the proper time to begin a street crossing. Dog guides move in response to directions from their handlers but may disobey commands to avoid danger.

Accessible Pedestrian Signals: A Guide to Best Practice 19 NO AID Not all persons considered blind use a long white cane or dog guide. People who are visually impaired often rely on their remaining sight and auditory and tactile cues in their surroundings for orientation and travel. Some may also use aids such as telescopes for specifi c tasks. ORIENTATION AND MOBILITY TRAINING Many pedestrians who are visually impaired or blind have received orientation and mobility training, provided by an Orientation and Mobility (O&M) Specialist. O&M Specialists usually have an undergraduate or graduate degree in teaching travel skills to persons who have visual impairments. Figure 2-4. Pedestrian with long white cane Figure 2-5. Pedestrian with dog guide

20 Chapter 2: Travel by Pedestrians Who are Blind or Who Have Low Vision Orientation is the ability to understand where one is located in space and Mobility refers to being able to travel through that space safely. Th e goal of most O&M training is to prepare a person who is visually impaired to travel in a variety of environments, both familiar and unfamiliar, and to assess new intersections and travel new routes. It is important to note that orientation training and assistance is not provided for every route that a person who is blind needs to travel. Figure 2-6. Visually impaired pedestrian crossing street with Orientation and Mobility Specialist

Accessible Pedestrian Signals: A Guide to Best Practice 21 How People Who are Blind or Visually Impaired Cross Streets TRADITIONAL TECHNIQUES Techniques and cues used in crossing streets are diverse and vary by the type of location and by the individual and his or her level of vision. Individuals who are blind or visually impaired often travel to unfamiliar areas and intersections and gather information from available sources in order to do so safely. Th e discussion of techniques below describes typical techniques used at unfamiliar intersections, although most travel by pedestrians who are blind is probably on routes with which they are familiar. However, it is also not uncommon for bus drivers or taxi drivers to provide incorrect information about the location or drop off a person at a slightly diff erent location than expected, so it is necessary to regularly confi rm information using nonvisual techniques described below. Once pedestrians who are blind are familiar with an intersection, they do not usually need to analyze the intersection and traffi c control system at length every time. However, they still may need to listen long enough to determine that they are at the correct location and that the signal is functioning as usual. Pedestrians who are blind will still need to detect the street, align to cross, identify the WALK interval, and maintain alignment while crossing. APS can particularly assist with the task of identifying the WALK interval at familiar and unfamiliar locations. DETECTING THE STREET Th e fi rst information needed by pedestrians who are blind is “Have I arrived at a street?” People who are blind or visually impaired use a combination of cues to recognize the street edge. Th ese may include: • Curb or the slope of the ramp • Truncated dome detectable warnings, if available • End of building line and open sound of the intersection • Sound of traffi c on the street beside them (the parallel street) • Sound of traffi c stopping on the street they are approaching (the perpendicular street) • Presence of pedestrians • Presence of an intersecting sidewalk IDENTIFYING THE STREET Th e next information needed for decision-making at unfamiliar intersections is: “Which street is this?”

22 Chapter 2: Travel by Pedestrians Who are Blind or Who Have Low Vision • Th is information is only occasionally provided in any accessible format. • 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. • Where necessary, and available, assistance may be sought from other pedestrians. ANALYZING INTERSECTION GEOMETRY Th e next information needed is: “What is the geometry of this intersection?” including: • Is my destination curb straight in front of me, or must I angle to the left or right to reach it? • How many streets intersect here? • How wide is this street? • Should I expect to encounter any islands or medians as I cross this street? • Am I standing within the crosswalk? Th is information may be immediately available to pedestrians having full vision, but it may not be possible for pedestrians who are blind to determine this information by listening to traffi c patterns. Incorrect or missing information for any of these questions may result in missing the destination curb or median. ANALYZING THE TRAFFIC CONTROL SYSTEM Next, pedestrians with visual impairments need to know: “What is the type of traffi c control system at this intersection?”, including: • Is this a signalized intersection? • Do I need to push a button to actuate the WALK interval? If so, where is the button? • Is the button close enough to the crosswalk that I will have time to push the button, position myself correctly at the crosswalk, and reestablish my alignment facing the destination curb before the onset of the WALK interval? • Which button controls the WALK interval for the street I want to cross? • Does it stop traffi c on one street, or all traffi c? • Do cars still turn during the WALK interval? • Is there a second button on the median or crossing island that I must push? • Will there be a surge of parallel traffi c telling me the WALK interval has begun? Will I be able to hear it over other, concurrent traffi c sounds? Techniques for gathering this information include listening to traffi c patterns through several signal cycles and searching the sidewalk area for poles with

Accessible Pedestrian Signals: A Guide to Best Practice 23 pushbuttons. Missing information for any of these questions may result in failure to use pedestrian pushbuttons, not beginning the crossing during the WALK interval, not completing the crossing before perpendicular traffi c begins moving, and crossing at times other than the pedestrian phase. ALIGNING TO CROSS Before starting to cross, the pedestrian must align to cross or choose a heading for the crossing. Typical techniques for this task include maintaining the alignment used on the approach to the intersection and listening to parallel traffi c through a signal cycle to confi rm alignment to parallel traffi c. Th e need to use pedestrian pushbuttons often prevents the use of parallel traffi c for alignment. After pushing the button, the pedestrian must cross on the next pedestrian phase, which is usually the next time that traffi c begins moving parallel to the pedestrian’s crosswalk. IDENTIFYING THE WALK INTERVAL 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 need to know: “When does the WALK interval begin?” In the most common technique utilized for crossing at signalized intersections, pedestrians who are blind or visually impaired begin to cross the street when there is a surge of traffi c on the street parallel to their direction of travel. Th is technique is dependent upon the presence of traffi c and consistent signal phasing. Various types of phasing and intermittent or low volumes of traffi c traveling parallel to the pedestrian may aff ect the reliability of that technique. MAINTAINING CROSSING ALIGNMENT Once the pedestrian who is blind has begun to cross the street, the next question is: “Am I headed straight towards my destination curb?” • Traffi c going in the same direction on the parallel street provides helpful auditory guidance to many persons if it is present. In addition, pedestrians who are blind may use traffi c waiting on the perpendicular street as a partial alignment cue. • Turning traffi c can make it diffi cult to hear and align with the traffi c traveling straight through the intersection. In the absence of traffi c on the parallel street, pedestrians who are blind are more likely to veer toward or away from the intersection.

24 Chapter 2: Travel by Pedestrians Who are Blind or Who Have Low Vision Changes in the Travel Environment TYPES OF CHANGES 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 use the above-mentioned techniques. INTERSECTION DESIGN CHANGES AND THEIR EFFECT ON TRAVEL TECHNIQUES • Wider streets require more precise alignment. • Large radius corners make alignment more diffi cult and increase crosswalk length. • Curb ramps and depressed corners make street detection and alignment diffi cult. • Medians and islands complicate wayfi nding and alignment. • Presence of slip lanes and splitter islands requires crossing in gaps in traffi c even at signalized intersections. • Crosswalk alignment is not consistent. • Curb extensions, also called bulb-outs or intersection chokers, sometimes complicate wayfi nding. • Raised crosswalks and tabled intersections may obliterate the sidewalk/ street boundary. DRIVER BEHAVIOR AND TECHNOLOGY OF AUTOS • Aggressive and inattentive drivers are moving faster and less likely to stop for pedestrians. • Th e technology of cars, including hybrid and electric cars, has become quieter, making them harder for pedestrians who are visually impaired to hear. • In many areas there is less pedestrian traffi c and drivers are less aware of pedestrians. SIGNALIZATION CHANGES Intersection signalization has become more complex. Details on signalization and the eff ect on travel by pedestrians who are blind are provided in Chapter 3.