Pedestrian Signal Safety - AAA Foundation for Traffic Safety

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DISCUSSION
SUMMARY OF STUDY FINDINGS
Observational Study of Pedestrians
Walking Speeds
• Older pedestrians walked slightly faster at intersections equipped with pedestrian countdown
(PCD) signals at most of the sites in the study. Mean walking speed (MWS) in the six
jurisdictions ranged from 3.98 feet/second (ft./sec.) to 4.60 ft./sec. at traditional signals
compared to 4.20 to 4.80 ft./sec. at PCD signals.
• Younger pedestrians also walked slightly faster at intersections equipped with PCD signals,
although comparisons at individual jurisdictions varied. MWS ranged from 4.85 ft./sec. to 5.30
ft./sec. at traditional signals compared to 5.00 to 5.30 ft./sec. at PCD signals.
• Walking speeds for older pedestrians were generally slower than for younger pedestrians by
about 0.80 ft./sec., although this varied by jurisdiction and type of intersection. Differences in
MWS between the two age groups were statistically significant at the 95-percent confidence
level for both traditional and PCD signals.
• Pedestrians with mobility impairments and without wheelchairs had appreciably slower walking
speeds—their mean was 3.30 ft./sec. when averaged across all six jurisdictions.
• The 15th-percentile speeds for younger pedestrians varied from 4.10 to 4.60 ft./sec. at
traditional signals and from 4.10 to 4.70 ft./sec. at PCD signals.
• The 15th-percentile speeds for older pedestrians varied from 3.40 to 3.80 ft./sec. at traditional
pedestrian signals (TPS) and similarly from 3.40 to 4.00 ft./sec. at PCD signals.
Start-Up Times
• Older pedestrians had slower start-up times, but this varied by intersection and leg of
intersection. The mean start-up times varied from 1.60 sec. to 2.90 sec. for older pedestrians.
Signal Compliance
• The differences in pedestrian signal compliance at the two signal types were difficult to
interpret and may have been a result of other factors at the intersection, such as pedestrian
actuation, street width, and availability of gaps. Older pedestrians generally had a higher rate
of compliance than their younger counterparts at the same intersections.
• As with signal compliance, the differences in the percentage of young pedestrians left in the
intersection at the onset of the DON’T WALK (DW) interval for the two signal types varied by
jurisdiction. The percentage of older pedestrians left in the intersection was negligible for both
signal types.