Pedestrian Clearance Intervals at Modern Intersections: Implications for the Safety of Pedestrians who are Visually Impaired

Blind Pedestrians and the Changing Technology and Geometry of Signalized Intersections: Safety, Orientation, and Independence

“…The pedestrian interval during which pedestrians begin crossing is indicative of safety. Traffic engineers time pedestrian signals with the expectation that pedestrians will begin crossing when the Walk signal is on, and the length of the pedestrian phase is based on that assumption (Barlow, Franck, Bentzen, & Sauerburger, 2001;McKinley, 2001). The percentage of crossings that were initiated during each interval of the pedestrian phase and the percentage that were completed after the onset of perpendicular traffic are presented for each city and across all cities in Table 1.…”

Street Crossings: Analyzing Risks, Developing Strategies, and Making Decisions

“…Today, the task of crossing streets is complex. Intersections and traffic signals are unpredictable (Barlow, Franck, Bentzen, & Sauerburger, 2001), right-turn-on-red and other features require adaptations to the standard street-crossing procedure (Sauerburger, 1998), cars are quieter, and vehicular sounds are no longer reliably present (Barlow, Bentzen, & Tabor, 2003;Bentzen, Barlow, & Franck, 2000;Carroll & Bentzen, 1999;Sauerburger, 1989Sauerburger, , 1995Sauerburger, , 1999. The population of independent travelers with visual impairments who cross streets now includes people with additional considerations (such as elderly people; children; and people with cognitive, mobility, and/or hearing disabilities in addition to visual impairment) that require adaptations to the standard street-crossing techniques,.…”

Crossroads: Modern Interactive Intersections and Accessible Pedestrian Signals

“…At interactive actuated intersections, pedestrians are expected to press a button that tells the intersection controller (a type of computer) to allow sufficient time for a pedestrian to cross the street. At a wide street with low volumes of traffic on side streets, the pedestrian timing can be as much as 20 seconds more than the time allowed for vehicles (Barlow, Franck, Bentzen, & Sauerburger, 2001;McKinley, 2001). The expectation of interaction between pedestrians and signals is commonly misunderstood even by sighted pedestrians, resulting in pedestrian pushbuttons that are accompanied by paragraphs of instructions (see Figure 1).…”

“…In Part 4, Section E.06, engineers are specifically encouraged to consult with pedestrians who are blind and O&M instructors when considering installations of APS. Before they provide such consultation, O&M instructors, other blindness professionals, and consumers who are blind should understand the typical functioning of actuated intersections and pedestrian signals, as described by Barlow et al (2001) and Barlow and Franck (1999), know what kinds of APS are available, and understand the features of the APS. Vision professionals who are involved in such consultation need to be aware of their role in installation decisions, regulations pertaining to the installation of APS, and potential problems and solutions.…”

“…Modern APS provide the same information that is provided by visual pedestrian signals in both quiet audible and vibrotactile formats and respond to levels of ambient noise, so they are not unnecessarily loud. Barlow et al (2001) and Barlow and Franck (1999), know what kinds of APS are available, and understand the features of the APS. Vision professionals who are involved in such consultation need to be aware of their role in installation decisions, regulations pertaining to the installation of APS, and potential problems and solutions.…”