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43 CHAPTER 7 Findings From the Field Study The field data provided information on several pedestrian · Young--consists of pedestrians between the ages of 13 and and motorist behaviors. This chapter summarizes those 60, and findings. · Old--includes pedestrians older than 60. For specific variables, the following data reduction proto- col was used. For pedestrians crossing in groups and clusters, The gender of the pedestrian was also recorded if the tech- observers only considered the leading pedestrian or the nician was able to determine the information from the field pedestrian closest to the oncoming traffic. All pedestrians in observation or later in the office during the video data reduc- a group or cluster were counted as a single pedestrian cross- tion effort. ing event. For the dataset of 3,155 crossings, 74 percent of the A total of 3,155 pedestrian crossings were recorded during observations represented crossings of individuals, 18 percent this study. Of that, 81 percent (2,552 pedestrians) were were groups (over three-fourths being groups of two), and 8 observed as "walking." The remaining 19 percent of the pedes- percent were clusters (most of which occurred at sites show- trians (603) were observed to be running, both walking and ing a red indication, i.e., pedestrians are restricted by pedes- running during the crossing, or using some form of assistance trian signal indications). (e.g., skates or bicycles). These 603 data points were not Non-staged (or general population) pedestrians were rep- included in the following analyses. Also not included in the resented in the descriptive statistics presented in this chapter. analyses were the 107 walking pedestrians whose ages could not For computing motorist compliance rates, the staged pedes- be estimated and the 6 pedestrians whose genders could not be trians were also used. determined. Table 18 lists walking speeds by age group and gender. The walking speed values for older pedestrians are lower than Walking Speed those for younger people. For young pedestrians, the 15th per- One of the pedestrian characteristics collected during field centile walking speed was 3.77 ft/s (1.15 m/s). Older pedestri- studies conducted as part of this TCRP/NCHRP study was ans had a slower walking speed with the 15th percentile being the time for the pedestrian to cross to the middle of the street 3.03 ft/s (0.9 m/s). The average walking speed was 4.25 and 4.74 or median and then to the other side of the street. Using the ft/s (1.3 and 1.45 m/s) for old and young pedestrians, respec- distances being traversed, the walking speeds of the pedes- tively. Figure 22 illustrates the distribution of the walking trians were determined. The walking speeds associated with speeds along with the current MUTCD walking speed and the different roadway conditions and pedestrian characteristics walking speed recommended by the U.S. Access Board (57). are available from the dataset. Various statistical analyses were used to better understand walking speed and to explore Age Group Comparison its relationship with the roadway environment and pedes- trian characteristics. Appendix N provides more details on An F test was used to find out if the walking speeds by gen- walking speed findings. This section provides a summary. der and age were statistically different. Table 19 shows the results of the tests. The male, female, and combined male and female older pedestrian groups had 15th percentile walking Pedestrian Walking Speed by Age Groups speeds that were statistically different from the 15th percentile To permit comparisons with other studies, the data were walking speeds of the younger pedestrians. For example, the grouped to reflect the following: 15th percentile walking speed of 3.03 ft/s (0.9 m/s) for older

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44 Table 18. Walking speed by gender and age group. Age Groups Walking Speed, ft/s (m/s) Sample Size 15th Percentile 50th Percentile Male Young 1434 3.75 (1.14) 4.78 (1.46) Old 75 3.11 (0.95) 4.19 (1.28) ALL 1509 3.67 (1.12) 4.75 (1.45) Female Young 890 3.79 (1.16) 4.67 (1.42) Old 31 2.82 (0.86) 4.41 (1.34) ALL 921 3.75 (1.14) 4.67 (1.42) Both Genders Young 2324 3.77 (1.15) 4.74 (1.45) Old 106 3.03 (0.92) 4.25 (1.30) ALL 2430 3.70 (1.13) 4.72 (1.44) pedestrians was statistically different from the 15th percentile young female group walked slightly slower (4.67 ft/s [1.4 walking speed of 3.77 ft/s (1.15 m/s) for younger pedestrians. m/s]) than the young male group (4.78 ft/s [1.5 m/s]). For the comparison done with the 50th percentile walking speeds, the female groups did not show a statistical difference. Comparison of TCRP/NCHRP Walking It is believed that this lack of difference was influenced by the Speed Findings with Previous Work small number of older women within the study set (only 31 older women pedestrians). As documented in Appendix M, several studies have exam- In most cases, the walking speeds of the male and female ined walking speed, including pedestrian groups were similar. The only statistical difference in gender among the age groups was for the 50th percentile · Manual on Uniform Traffic Control Devices for Streets and walking speed of the young group as shown in Table 19. The Highways (1), 100 Access Board Recommendation 90 80 70 Cumulative Percent (%) 60 50 40 30 20 10 MUTCD "Normal" Walking Speed 0 0 1 2 3 4 5 6 7 8 9 10 Walking Speed (ft/s) Young Old Access Board MUTCD Figure 22. Older than 60 (Old) and 60 and younger than 60 (Young) walking speed distribution.

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45 Table 19. F-test results for gender and age group walking speed comparisons. 15th 50th Comparison Walking F 15th P Walking F 50th P F1,n-1,0.05 Speed (ft/s) Speed (ft/s) Male, 3.11 3.75 22.59 0.0001 4.19 4.78 19.2 0.0001 3.85 Old & Young Female, 2.82 3.79 24.8 0.0001 4.41 4.67 1.78 0.1825 3.85 Old & Young Both Age Groups 3.67 3.75 2.91 0.0882 4.75 4.67 2.91 0.0882 3.84 Male & Female Old 3.11 2.82 2.67 0.1053 4.19 4.41 1.54 0.2174 2.91 Male & Female Young 3.75 3.79 0.70 0.4029 4.78 4.67 5.31 0.0213 3.84 Male & Female Both Genders 3.03 3.77 35.25 0.0001 4.25 4.74 14.96 0.0001 3.84 Old & Young Bold cells indicate the walking speeds are different between the comparison groups. · Public Rights-of-Way Access Advisory Committee draft Figure 23 summarizes the 15th percentile findings from sev- 2002 guidelines (57), eral studies. The figure also includes key characteristics of the · LaPlante and Kaeser (58), study, such as whether the data reflect old or young pedestri- · 1982 Transportation and Traffic Engineering Handbook (59), ans. As shown in Figure 23, previous work has identified or · Knoblauch et al. (14), recommended walking speeds as low as 2.2 ft/s (0.7 m/s) and · Guerrier and Jolibois (60), as high as 4.27 ft/s (1.3 m/s) for a 15th percentile value. Two · Milazzo et al. (61), studies with databases known to include over 2,000 pedes- · 2000 Highway Capacity Manual (23), trian crossings are the 1996 Knoblauch et al. study (14) with · 2001 Traffic Control Devices Handbook (62), data collected in 1993 and this TCRP/NCHRP study with · Guidelines and Recommendations to Accommodate Older data collected in 2003. Table 20 summarizes the findings for Drivers and Pedestrians (63), young, old, and all pedestrians from these two studies. · Dahlstedt (11) in a study in Sweden, Based on their findings, Knoblauch et al. suggested a value · Coffin and Morrall (12), of 4.0 ft/s (1.22 m/s) for younger pedestrians and 3.0 ft/s (0.9 · Dewar (8) in Human Factors in Traffic Safety, m/s) for older pedestrians for traffic signal design. The U.S. · Bennett et al. (9) in a 2001 Australian Institute of Trans- Access Board has recommended a walking speed of 3.0 ft/s portation study, and (0.9 m/s). LaPlante and Kaeser (58) in a September 2004 ITE · Akçelik & Associates (64) in a 2001 Australian study. Journal article recommended 3.5 ft/s (1.1 m/s) minimum walking speed for curb-to-curb for determining the pedes- Most of the studies have provided values at the 15th per- trian clearance interval and 3.0 ft/s (0.9 m/s) walking speed centile level. The 15th percentile level is frequently used to set from top of ramp to far curb for the entire walk plus pedes- policy for roadway design or traffic operations, but not in trian clearance signal phasing. every situation. The portion of the population to include in This TCRP/NCHRP study had a similar number of young calculating the 15th percentile value also varies. For example, pedestrians within the dataset as the 1993 study (over 2,000 in setting driver eye height values for use in stopping sight pedestrians). The TCRP/NCHRP study, however, found a distance, the question of whether to include the higher eye slower walking speed (3.77 ft/s [1.15 m/s], as compared with heights represented by trucks and by drivers in sport utility 4.02 ft/s [1.23 m/s]). Therefore, the findings do not support vehicles (SUVs) was debated. (For the final determination, the suggestion of a 4.0 ft/s (1.22 m/s) walking speed for traffic values for trucks and SUVs were not included in setting the signal design. If both older and younger pedestrians are con- design driver eye height; see NCHRP Report 400[65].) sidered, the TCRP/NCHRP study found 3.7 ft/s (1.13 m/s), A similar debate exists for walking speed. Should "walking while the larger 1993 study found 3.53 ft/s (1.08 m/s). Based speed" include all crossing maneuvers, even if the pedestrian on the larger number of older pedestrians included in the 1993 is running? Should those using some form of wheels, whether study, a recommendation of 3.5 ft/s (1.1 m/s) for the timing of it be in-line skates or a wheelchair, be considered? Should a traffic signal design seems more reasonable. If older pedes- design be based only on older pedestrians or a mix of older trians are a concern at the intersection, then a signal timing and younger pedestrians? design using a 3.0 ft/s (0.9 m/s) walking speed is suggested.