Pedestrian Signal Safety - AAA Foundation for Traffic Safety

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All surveyed pedestrians were asked to explain the meaning of the PCD indication. All of the
pedestrians provided a satisfactory explanation of the countdown indication—either that the
countdown was the time remaining to cross or the time until the light turns red. Twenty-three of the
pedestrians had a preference regarding the use of TPS or PCD signals, all of whom preferred PCD
signals. Similarly, all but one of the surveyed pedestrians indicated that the PCD signal was helpful in
crossing the street safely.
EFFECT OF CHANGING WALKING SPEEDS ON PEDESTRIAN CLEARANCE TIMES
Table H-11 displays the required pedestrian clearance time and the pedestrian clearance time plus
a 7-sec. WALK time. For the case study intersection in Orange County, the available green time was
not provided by the agencies and, therefore, analysis of the adequacy of the pedestrian interval could
not be undertaken.
Table H-11. Pedestrian WALK and clearance time durations for case study intersection in Orange
County, California.
Approach/
crosswalk
Northbound/
south
Southbound/
north
Eastbound/
west
Length
(ft.)
Clearance time (sec.)
3.00
ft./sec.
3.50
ft./sec.
4.00
ft./sec.
Clearance time with 7-sec.
WALK (sec.)
[total WAL K time]
3.00 3.50 4.00
ft./sec. ft./sec. ft./sec.
Available
green
(sec.)
115 38 33 29 45 40 36 N/A*
110 37 31 28 44 38 35 N/A*
71 24 20 18 31 27 25 N/A*
Westbound/
east
58 19 17 15 26 24 22 N/A*
* Note: Available green time not provided.
TRAFFIC OPERATIONS ANALYSIS
Table H-12 shows the intersection operational and geometric characteristics for the Orange County
case study intersection. Because volume data were not available from the jurisdiction, existing
volumes were estimated based on the operational and geometric characteristics of the intersection.
Total intersection volume was estimated at 6,500 peak-hour vehicles, with 2,000 vehicles and 1,250
vehicles on the major and minor street approaches, respectively. This approach produced more
of a saturated/lower level of service (LOS) condition at a “base” level scenario similar to the base
condition LOS at the Montgomery County, Maryland case study intersection.
The modeled peak-hour volumes at the Orange County case study intersection ranged from a
decrease of 10 percent to an increase of 15 percent of existing (modeled) peak-hour volumes.
Comparatively, as the White Plains, New York case study intersection had the lowest total intersection
traffic volume range analyzed (1,611 to 2,059 peak-hour vehicles), the Orange County case study
intersection had the greatest total intersection traffic volume range analyzed (5,850 to 7,475 peakhour
vehicles).