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23 especially with false (unused) pedestrian actuations. Also, tional splitter island. The location of the distal crosswalk because the signals rest in green the majority of the time, requires a median refuge island to be utilized if a two-stage it is possible that drivers may react slowly (or not at all) to crossing is necessary. the red stop indication. Pedestrian hybrid beacon one or two stage: The PHB Grade-Separated Crossing or HAWK signal aims to be more efficient than a conven- tional signal by allowing vehicular traffic to move during the Grade separation allows pedestrians to cross the road with- pedestrian "Flashing Don't Walk" phase. During that phase out affecting the movement of vehicles. Grade-separated facil- a flashing red indication for drivers allows traffic to proceed ities must accommodate all persons, including those with after stopping if no pedestrian is in the crosswalk. This phas- vision and mobility impairments. To accommodate all users, ing scheme allows for less vehicular delay while providing these treatments may require ramps or elevators. Grade sep- similar pedestrian-related benefits to a regular signal. aration is typically used in cases where pedestrians must cross Distal pedestrian-actuated signal one or two stage: very busy streets or freeways, and where pedestrian volumes Entry-lane and exit-lane pedestrian-activated signals used are extraordinarily high. Grade-separated facilities should not at a distal crosswalk location or in a zigzag configuration be considered where opportunities for crossing at the street could be used to establish a one- or two-phased pedestrian level are available on a regular basis because this discourages crossing that maximizes the storage capacity of the exit use of the facility. lane during a vehicle red phase. If a two-phase crossing is used, a median refuge island would be necessary. Depend- Pedestrian overpass: Overpasses are the more common ing on pedestrian route patterns, these configurations may form of grade separation in the United States and are acces- result in an increase in the travel time for pedestrians com- sible via stairs, ramps, or elevators. Overpasses should be pared to a crossing at the traditional splitter island. designed so that they provide the ability for multiple users Distal/zigzag PHB one or two stage: The PHB could also to pass by or around each other. be used at a distal location or in a zigzag arrangement, com- Pedestrian underpass: Pedestrian underpasses are most bining the advantage of the extra queue storage capacity at easily accounted for and installed during the design and the exiting approach of the roundabout with more efficient construction process. Underpasses installed as a retrofit signal phasing. Depending on pedestrian route patterns, require costly underground construction. Underpasses may these configurations may result in an increase in the travel be difficult to keep clean and safe, but with proper design time for pedestrians compared to a crossing at the tradi- and lighting these challenges can be overcome.