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17 · Pedestrian signs to encourage looking behavior, crosswalk compliance, and pushbutton activation; · In-pavement warning lights with advance signing to inform drivers of the crossing; and · "Countdown signals" with a pedestrian (Walk/Don't Walk) signal if appropriate for the treatment (e.g., high-intensity activated crosswalk [HAWK] signal or other pedestrian traffic control signals). Streets with lower speeds or traffic volumes may not require multiple treatments to be safe and effective. In these less complex street environments, single treatments may be just as safe and effective as multiple treatments. Traffic Signal and Red Beacon Displays Figure 7. HAWK signal in Tucson, Arizona. Pedestrian devices that include a red signal indication vary. These devices include traffic signals and displays with solid or and/or high-speed streets. For example, several studies flashing red beacons. There is limited experience with inter- (28-30), including the study done for this TCRP/NCHRP section pedestrian signals (commonly known as "half project (see Appendix L), have documented driver yielding in signals") because their current operation is limited to a few the 90 to 100 percent range. The steady red signal indication cities (e.g., Seattle and Portland). They are also used in some provides a clear regulatory message that typically receives a provinces of Canada (British Columbia being the most more uniform control response than warning signs or flash- notable). ing beacons. Critics of the concept have suggested that vehi- For vehicle control, these pedestrian signals typically use a cle crashes will increase because of signalization on the major traditional traffic signal head on the major street and a Stop street or conflicting control messages from the signal and sign on the minor street (if applicable). Midblock pedestrian Stop sign. However, crash analyses in the city of Seattle have signals are used in Europe (as well as Canada and the United documented that, with consistent operation, the half signals States), where they are referred to as pedestrian crossovers can actually reduce vehicle-vehicle crashes and pedestrian- (Toronto) or pelicans or puffins (Europe). Pedestrian move- vehicle conflicts (31-34). Inconsistent and somewhat confus- ments across the major street are controlled by traditional ing operation (e.g., flashing green) of half signals in British pedestrian Walk/Don't Walk signals for red signal indication Columbia has generated poor compliance with Stop signs on devices. the minor street (35). The signal display sequences for these pedestrian signals In summary, devices with a red signal indication show vary among installations. Half signals in the city of Seattle promise as a pedestrian-crossing treatment for high-volume, dwell in steady green and then cycle to steady yellow and then high-speed arterial streets. The field studies conducted in steady red when activated by a pedestrian. The HAWK signals this project indicated that these red signal or beacon devices in Tucson (see Figure 7) are modeled after emergency vehicle were most effective at prompting motorist yielding (all sites beacons and are dark until activated by a pedestrian; then had motorist compliance greater than 90 percent) on high- they cycle through flashing yellow, steady yellow, steady red, volume, high-speed streets. It may be necessary to determine and then flashing red. Half signals in the Vancouver area of the most effective signal indication display sequence, as well British Columbia dwell in flashing green and, on activation, as the traffic conditions that would accommodate the use steady green (for some installations), steady yellow, and then of minor street Stop sign control and major street signal steady red. The midblock pedestrian signal in Los Angeles control. shows a green arrow, cycles to a steady yellow, and then cycles to steady red during the walk interval. During the flashing Flashing Beacons Don't Walk interval, drivers see a flashing red indication and, after stopping, may proceed if the crosswalk is not occupied. The use of flashing beacons for pedestrian crossings is Despite differences in signal operation, the pedestrian or prevalent in the United States (see Figure 8). In some half signals have been documented as successful in encourag- instances, there are concerns that the overuse of flashing bea- ing motorists to yield to pedestrians along high-volume cons or the continuous flashing at specific locations has