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68 C H A P T E R 6 This chapter provides a methodology for assessing wayfinding and alignment challenges for pedestrians who are blind. The most important underlying principle in the design of pedestrian crosswalks is that the design should be intuitive for its users. Many pedestrians who are blind or who have low vision have received orientation and mobility instruction and training for independent travel, but their training may not have covered roundabouts and intersections with CTLs, particularly if they received the training several years ago. Furthermore, pedestrians likely did not receive training at the specific location they may be trying to cross. An intuitive design of the crosswalk therefore is critical to make sure that pedestrians understand the purpose of the crosswalk and the rules governing the interaction between pedestrians and drivers. As discussed in Chapter 3, pedestrians who are blind or who have low vision may not be aware of the presence of a roundabout where two roads intersect or of a CTL at the intersection. If the design and wayfinding features of the sidewalk do not guide them to the correct crossing location, or provide cues to the proper crosswalk heading, they may cross at a location where crossing is not intended, or veer out of the crosswalk and possibly along the vehicular travel lanes or into the roundabout circulatory roadway. Itâs important to evaluate each crossing from each approach direc- tion in light of the three wayfinding tasks outlined in Chapter 3, determining the crossing location (or locating the crossing), aligning to cross, and maintaining correct heading while crossing. 6.1 Determining the Appropriate Crossing Location The first task of the pedestrian is to determine the appropriate crossing location or to locate the crosswalk. Sidewalks, curb ramps, and other features should guide pedestrians to the point where the designer wants them to cross the roadway and to discourage or prevent pedestrians from crossing at other locations. This should also be considered in the design of islands. As shown in Figures 6-1 and 6-2, the zone discussed is on the approach to the roundabout or CTL as pedestrians walk toward the crossing location from either direction, including crossing from islands to the sidewalk. In evaluating wayfinding features for determining the crossing location, six basic questions should be considered by designers, as presented in Table 6-1. Each question is discussed further with additional details and graphics provided in Chapters 4 and 5. 6.1.1 Do the Sidewalks Lead to the Crosswalks? Sidewalks should lead to the crosswalks, particularly in designs where the sidewalks are not beside the roadway. On islands, the walkway should be defined to give clear guidance to all pedestrians about the appropriate crossing location (see Chapter 6.4). Wayfinding Assessment
Wayfinding Assessment 69 Figure 6-1. Illustration of zone to determine the crossing location at roundabouts. Figure 6-1 shows a drawing of a single-lane roundabout. Yellow shaded zones are seen on the sidewalk approach- ing the crosswalk on both entry and exit sides, denoting the region where wayfinding features to assist in deter- mining the crossing location should be considered. Yellow shaded zones are also seen on the splitter island. Figure 6-2 shows a drawing of a CTL. Yellow shaded zones are seen on the sidewalk approaching the crosswalk on both curb and island sides, denoting the region where wayfinding features to assist in determining the crossing location should be considered. Figure 6-2. Illustration of zone to determine the crossing location at CTLs.
70 Crossing Solutions at Roundabouts and Channelized Turn Lanes for Pedestrians with Vision Disabilities: A Guidebook 6.1.2 Is Separation Provided Between the Sidewalk and the Curb (required by PROWAG-NPRM)? Sidewalks should be separated from the curbs by a landscape strip, except at the crosswalks. A landscape strip at least 2 ft wide should be provided between the sidewalk and the curb on each side of the curb ramp, and should be a surface that is detectable under foot, such as grass, gravel, pebbles, or small shrubs. Bricks, cobblestone-type pavers, or colored paved surfaces do not provide sufficient cue to prevent blind pedestrians from crossing into the circulatory roadway. This should be provided on the approach to the crosswalk from either direction (see Figure 6-1). If there is insufficient right-of-way to provide a landscape strip as described above, fencing or bollards and chain should be provided on either side of the crosswalk to prevent crossing into the circulatory roadway. PROWAG-NPRM requires a lower edge or chain that is not more than 15 in. above the walking surface; a higher chain or fence may be needed to avoid tripping by sighted pedestrians. If bollards are used, they must be connected by chains or other material to prevent pedestrians from walking between them. 6.1.3 Is the Edge of the Street Clearly Defined (required by the Department of Transportationâs ADA Regulations and PROWAG-NPRM)? A detectable warning surface (truncated domes) should be provided for the width of the ramp or for the area that is level with the street. The surface must be a minimum of 2 ft deep in the direction of pedestrian travel covering the entire area that is level with the street so that a pedes- trian does not easily step over or around the surface. When a raised crosswalk is installed that brings the crosswalk up to sidewalk level, the detectable warning surface is the only indication of the street or sidewalk boundary to a blind pedestrian. 6.1.4 Are There Other Features that Could be Mistaken for Curb Ramps? If bike ramps are planned, they must be carefully designed to avoid misleading pedestrians. The ramp should be angled at a more than 45-degree angle toward the roadway rather than Question Notes 1. Do the sidewalks lead to the crosswalks? See Chapters 4.1 and 5.1 for details. 2. Is separation provided between the sidewalk and the curb? See Chapters 4.1 and 5.1 for details. This is required by PROWAG-NPRM at round- abouts and is considered a good practice at CTLs. 3. Is the edge of the street clearly defined by detectable warning surfaces? See Chapters 4.1 and 5.1 for details. This is required by the Department of Transportationâs ADA regulations and PROWAG-NPRM. 4. Are there other features that could be mistaken for curb ramps? See Chapters 4.1 and 5.1 for details. 5. Are traffic control devices accessible? See Chapters 4.2 and 5.2 for details. This is required by PROWAG-NPRM. The specifications are in MUTCD 4.E. 6. Are other treatments needed or desired to assist with locating the crosswalk? See Chapters 4.2 and 5.2 for details. Table 6-1. Considerations for determining the crossing location.
Wayfinding Assessment 71 parallel to the sidewalk. Detectable warning surfaces should be installed at the top of the ramp and at the junction with the sidewalk and aligned with the edge of the sidewalk to alert blind pedestrians of the presence of the ramp. 6.1.5 Are Traffic Control Devices Accessible (required by PROWAG-NPRM and specifications in MUTCD 4.E)? If a pedestrian signal is present, an APS with an appropriate audible pushbutton locator tone has to be provided. Pedestrians need to be able to locate and use a pedestrian pushbutton without having to deviate far from the path of travel or the crosswalk. Audible indications, including a pushbutton locator tone to assist blind pedestrians in locating a pushbutton, should be provided even on devices such as RRFBs, which do not provide a walk indication. The sound of the push- button locator tone can also provide information about the location of the crosswalk. 6.1.6 Are Other Treatments Needed or Desired to Assist with Locating the Crosswalk? Bar tiles or guidance tiles are used in other countries to notify pedestrians of the location of the crosswalk at roundabouts and CTLs. These types of surfaces provide information about the crosswalk location to pedestrians who use dog guides or long canes but are not trailing the edge of the sidewalk with their canes. Pilot research suggested that bar tiles may work well to address concerns of wheelchair users while helping pedestrians who are blind locate crosswalks and align to cross. 6.2 Aligning to Cross and Establishing the Correct Heading Aligning to cross is the necessary task after finding the crosswalk. The technique most com- monly used by blind pedestrians at a typical intersection is aligning with traffic traveling parallel to the crosswalk. At roundabouts and CTLs this technique is generally not available since there is no parallel traffic. Blind pedestrians must use a combination of sidewalk and curb ramp features and the movement of traffic (perpendicular to their path) as primary cues to the direction of travel on the crosswalk. A mistake in alignment may put pedestrians who are blind outside the crosswalk area, or headed toward the circulatory roadway, and could be a dangerous, as well as confusing, mistake. Figure 6-3 shows the areas where this task takes place and where the designer needs to focus in considering alignment cues. In evaluating wayfinding features for the task of aligning to cross and for establishing the cor- rect heading, six basic questions should be considered by designers, as presented in Table 6-2. Each question is discussed further, with additional details provided in Chapters 4 and 5. 6.2.1 Is the Curb Ramp Width the Same as the Crosswalk Width? The width of the curb ramp and the sidewalk leading to the crosswalk should be the same width as the crosswalk. If the sidewalk on either end of the crosswalk is wider than the crosswalk, pedestrians who are blind may cross outside the crosswalk area. If the ramp or cut-through area is narrower than the crosswalk, the curb can be a tripping hazard and can cause confusion as pedestrians who are blind may think that they have veered outside the crosswalk when they have not. Detectable warning surfaces must also be the full width of the area that is level with the street, so it also must be the full width of the crosswalk.
72 Crossing Solutions at Roundabouts and Channelized Turn Lanes for Pedestrians with Vision Disabilities: A Guidebook 6.2.2 Are the Curb Ramp Slopes Aligned with the Crossing? All curb ramps should be oriented so that the running slope is in the same direction as the direction of travel on the crosswalk. The slope of the ramp can influence the direction of travel of blind pedestrians on the crosswalk, so it should align with the direction of the crosswalk. The greater the slope, the more potential influence there is. In addition, it can be difficult for wheel- chair users to make a turn at the base of the curb ramp and stay within the crosswalk; at best, it slows them and distracts them as they enter the street. Curb ramps and crosswalks should further be aligned perpendicular to the curb, gutter, and the travel lanes. To prevent tipping problems for wheelchair users, it is essential that the base Figure 6-3. Illustration of zone for aligning to cross at roundabouts. Figure 6-3 shows a drawing of a single-lane roundabout. Yellow shaded zones are seen on the crosswalk landing on both entry and exit sides, as well as on the curb and island. The shaded areas denote the regions where wayfinding features to assist in aligning to cross should be considered. Question Notes 1. Is the curb ramp width the same as the crosswalk width? See Chapters 4.1 and 5.1 for details. 2. Are the curb ramp slopes aligned with the crossing? See Chapters 4.1 and 5.1 for details. 3. Are the ramp edges aligned with the crossing? See Chapters 4.1 and 5.1 for details. 4. Is the detectable warning surface aligned with the slope of the curb ramp? See Chapters 4.1 and 5.1 for details. This is required by PROWAG-NPRM. 5. Are the push buttons in correct locations? See Chapters 4.2 and 5.2 for details. 6. Is there a need for additional treatments? See Chapters 4.2 and 5.2 for details. Table 6-2. Considerations for aligning to cross and establishing a correct heading.
Wayfinding Assessment 73 of the ramp be square to the gutter or grade break at the base of the ramp. Pedestrians who are blind also tend to use the gutter and curb line as an alignment cue and will often travel across the roadway on a path that is perpendicular to the curb line. On islands, both at roundabouts and CTLs, when the island is not a cut-through, the curb ramp slope can provide help with the detection of the crossing location and with the alignment for the crossing. See Chapter 6.4 for a detailed discussion. 6.2.3 Are the Ramp Edges Aligned with the Crossing? Returned edges on the curb ramp should be aligned with the direction of the crosswalk. If there are returned edges on the curb ramps, they may serve as a cue to blind pedestrians and should be in line with the crosswalk. Returned curbs should not be used in locations without landscaping or other features where they may be a tripping hazard to pedestrians walking across the ramp area. Flares (sloped areas beside the ramp) are not needed if there is landscaping beside the ramp. The ramp should be the width of the entire crosswalk, and the flares, if needed, can be outside the crosswalk area. 6.2.4 Is the Detectable Warning Surface Aligned with the Slope of the Curb Ramp (required by PROWAG-NPRM)? The domes of the detectable warning surface should be aligned with the slope of the ramp (required by PROWAG-NPRM). This is to make it easier for wheelchair users to travel between the domes on the slope of the ramp. The alignment of the detectable warning surface is not intended to be a cue for the direction of travel on the crosswalk, but some pedestrians who are blind will try to align with it, nonetheless. It is not possible for most people who are blind to accurately align themselves with the truncated dome surface. Nonetheless, aligning the detect- able warning surface edges, the curb/gutter, and the ramp slope with the direction of travel on the crosswalk can provide consistency that can lead to better alignment. 6.2.5 Are the Pushbuttons in Correct Locations? When a pedestrian pushbutton is used, either with a pedestrian signal, a PHB, or an RRFB, it should be next to the crossing and beside a level area to allow access for wheelchair users. Most pushbutton devices include a tactile arrow that must be aligned with the direction of travel on the crosswalk. That arrow must be located within 5 ft of the crosswalk line and should be no further than 6 ft from the curb, if possible. Audible devices, either APS or audible information devices, provide a pushbutton locator tone and that tone may be audible across a short crossing and may help with alignment and maintaining the correct heading when crossing. The push- button locator tone is supposed to be audible no more than 12 ft from the pushbutton, so it may not provide alignment help on longer crossings. 6.2.6 Is There a Need for Additional Treatments? For approaches that do not meet the above criteria, additional treatments may be needed to assure that a blind pedestrian is able to correctly align with the crossing. A tactile bar tileâtype surface perpendicular to the direction of travel on the crosswalk was found in pilot research to lead to better initial alignment. There is a need for more research on the appropriate placement of such surfaces and the potential effect on wheelchair users.
74 Crossing Solutions at Roundabouts and Channelized Turn Lanes for Pedestrians with Vision Disabilities: A Guidebook 6.3 Maintaining the Correct Heading While Crossing Staying within the crosswalk area while crossing can be critical to safety, driver expectation, and orientation. Critical zones for this task are the area of the crosswalk within the street as shown in the Figure 6-4. In evaluating wayfinding features for the task of maintaining the correct heading while cross- ing and staying within the crosswalk, four basic questions should be considered by designers, as presented in Table 6-3. Each question is discussed further, with additional details provided in Chapters 4 and 5. Figure 6-4. Illustration of zone for maintaining the correct heading at roundabouts. Figure 6-4 shows a drawing of a single-lane roundabout. A yellow shaded zone is shown across the entire crosswalk for both entry and exit sides, denoting the region where wayfinding features to assist in maintaining the correct heading should be considered. Question Notes 1. Is the crossing configured at the shortest distance practical? See Chapters 4.1 and 5.1 for details. 2.Is the crossing aligned perpendicular to the curb and splitter edges? See Chapters 4.1 and 5.1 for details. 3. Are markings clearly visible? See Chapters 4.1 and 5.1 for details. 4. Is there need for additional treatments? See Chapters 4.2 and 5.2 for details. Required by PROWAG-NPRM. Table 6-3. Considerations for maintaining the correct heading while crossing and staying within the crosswalk.
Wayfinding Assessment 75 6.3.1 Is the Crossing Configured at the Shortest Distance Practical? The shorter the crossing, the less exposure and less opportunity there is for the pedestrian to veer outside the crosswalk area. 6.3.2 Is the Crossing Aligned Perpendicular to the Curb and Splitter Edges? Good initial alignment makes it more likely that blind pedestrians will complete their crossing within the crosswalk. As noted in the alignment discussion, the crossing and the crosswalk need to be aligned with the edge of the street. 6.3.3 Are Markings Clearly Visible? For low-vision pedestrians, crosswalk markings provide critical information to assist them in staying within the crosswalk. Ladder markings with both longitudinal and transverse lines are preferred by individuals with low vision. 6.3.4 Is There a Need for Additional Treatments? For approaches that do not meet the above criteria, additional treatments may be needed to assure that a blind pedestrian is able to maintain correct heading during crossing. Raised cross- walks provide additional cues to assist blind pedestrians in staying within the crosswalk if they recognize the slope on the edges of the crosswalk. Detection is dependent on the steepness of that slope but slight changes in cross slopes are detectable by many pedestrians who are blind. As a pedestrian is crossing, the pushbutton locator tone of an APS or audible information device may provide a cue to the end of the crosswalk and heading direction. Tactile guide strips are used in some countries and have been experimented with in the United States to provide guidance, particularly if the crossing is more than two lanes. 6.4 Crossings from Channelization and Splitter Islands The second half of the crossing from triangular islands at CTLs or splitter islands of round- abouts can be problematic if the island does not provide crossing and alignment cues as noted above. Additional principles also need to be considered for the island environment. Figures 6-5 and 6-6 show the channelization island zone for a roundabout and a CTL, respectively. In general, the same wayfinding features that were discussed in the previous sections also apply to channelization islands. In addition, the following four questions should be considered by designers, as presented in Table 6-4. Each question is discussed further, with additional details provided in Chapters 4 and 5. 6.4.1 Are Islands Wide Enough to Provide Safe Refuge? The minimum width of an island (length in direction of pedestrian travel) should be 6 ft. The minimum width of cut-through areas should also be 6 ft (or the same width as the crosswalk if the crosswalk is wider than 6 ft). For areas with heavier pedestrian traffic (greenways, shared use paths, etc.), consider larger islands to provide adequate storage. 6.4.2 Are Transitions to the Roadway Clearly Defined? Detectable warning surfaces that denote street/sidewalk boundaries are needed on all edges of the islands where it is level with the street. All islands should be raised to clearly separate them
76 Crossing Solutions at Roundabouts and Channelized Turn Lanes for Pedestrians with Vision Disabilities: A Guidebook Figure 6-5. Illustration of zone for island crossings at a roundabout. Figure 6-5 shows a drawing of a single-lane roundabout. A yellow shaded zone is shown covering the island, denot- ing the region where wayfinding features to assist in navigating the splitter island should be considered. Figure 6-6 shows a drawing of an intersection with a channelized right turn lane. A yellow shaded zone is shown covering the island, denoting the region where wayfinding features to assist in navigating the splitter island should be considered. Figure 6-6. Illustration of zone for island crossings at a channelized turn lane.
Wayfinding Assessment 77 from the vehicular right-of-way. Painted islands are inaccessible (not detectable) to blind users and should not be used. The island size should be large enough to be visible to approaching drivers, and as required by AASHTO. 6.4.3 Are Paths Through the Island Clearly Identifiable? To define the path through the island and prevent disorientation, if a blind pedestrian veers from the crosswalk on approach to the island, it is most desirable to have landscaping outside of the walkway that is detectable under foot such as gravel, grass, or shrubs. Detectable landscaping clearly directs pedestrians to stay on the planned path through the island rather than take a dif- ferent path or shortcut. Completely paved islands, even with rough pavers or bricks, can result in confusion and disorientation for pedestrians who are blind. If the island is cut-through, the approach to the curb line of the cut-through areas needs to be aligned with the direction of travel on the crosswalk. If the island is not cut-through, atten- tion should be paid to the alignment of curb ramps, detectable warnings, and gutters to provide alignment cues. 6.4.4 Are Pushbuttons Accessible? There are somewhat different location needs for APS at signalized intersection than there are for audible information devices at unsignalized crosswalks. MUTCD 4E.08 requires pushbuttons and APS to be installed within 5 ft of the crosswalk line furthest from the center of the intersec- tion. There are no specific requirements in MUTCD for audible information devices, such as those installed at RRFBs. However, it is desirable for the device to be close to the crosswalk and to be downstream from the crosswalk to avoid having the device sounds between blind pedestrians and the vehicles they need to hear. In addition, devices also must be separated by at least 10 ft to allow pedestrians to distinguish which one is sounding. On small islands, that can be challenging to design and may require additional stub poles. Pushbutton information messages, a type of speech message provided when the pushbutton is held for more than one second, can be configured to provide street name information. This could be a very helpful orientation aid on islands at CTLs to differentiate the main street crossings. Question Notes 1. Are the islands wide enough to provide safe refuge? See Chapters 4.1 and 5.1 for details. 2. Are transitions to the roadway clearly defined? See Chapters 4.1 and 5.1 for details. 3. Are paths through the islands clearly defined? See Chapters 4.1 and 5.1 for details. 4. Are pushbuttons accessible? See Chapters 4.2 and 5.2 for details. Table 6-4. Considerations for crossings from channelization and splitter islands.
