Pedestrian Signal Safety - AAA Foundation for Traffic Safety

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For younger pedestrians, the mean walking speed (MWS) was 4.90 feet/second (ft./sec.) at traditional
intersections and 5.00 ft./sec. at countdown signals. As presented in Table D-3, the difference in MWS
was significant at the 95-percent confidence level. The median walking speeds were comparable to
MWS. The 15th-percentile walking speed represents the slower pedestrians at the intersection. The
15th-percentile speed was slightly slower at traditional signals (4.20 ft./sec.) than at PCD signals
(4.40 ft./sec).
Based on the combined approaches, a walking speed of 4.00 ft./sec. would accommodate the 15thpercentile
pedestrian who was under 65 years of age. However, one intersection approach, the minor
approach of University and Hamline, had a 15th-percentile speed lower than 4.00 ft./sec.
Table D-3. Significance testing of difference in mean walking speed at traditional and pedestrian
countdown signals for two age groups.
Subjects
Pedestrians
under 65
Pedestrians
65 and older
Intersection
type
Mean
Standard
deviation
Traditional 4.85 0.67
Countdown 5.03 0.62
Traditional 3.98 0.66
Countdown 4.31 1.10
Tcalc
-3.659
-1.855
Outcome
The difference
between means is
significant at 95
percent.
The difference
between means is not
significant at 95
percent.
For older pedestrians, MWS at PCD signals was 4.00 ft./sec., slightly slower than the MWS of 4.30 ft./
sec. at TPS. This relationship is opposite the relationship seen in the walking speeds of their younger
counterparts. However, as presented in Table D-3, this difference was not significant at the 95-percent
confidence level.
The 15th-percentile speed also was slightly slower at countdown intersections (3.70 ft./sec.)
compared to traditional signals (3.40 ft./sec.). Note that this was based on very small sample sizes.
When the approaches are considered together, a walking speed of 4.00 ft./sec. would accommodate
older pedestrians at these intersections. It would not accommodate the 15th-percentile speed.
Table D-4 presents the results of significance testing of the difference in MWS for younger
pedestrians and older pedestrians. As would be expected, the walking speed of older pedestrians
was significantly slower than the walking speed of younger pedestrians, regardless of the type of
pedestrian signal.