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4.50
4.00
Walking Speed (ft/s) 3.50
3.00
2.50
2.00
1.50
1.00
0.50
0.00
1950 all ages (58)
1950 older (58)
1998 Guerrier, younger (60)
Dahlstedt, older (11)
2001 Akcelik, w/walking difficulties,
1998 Guerrier, older (60)
1982 Engineering Handbook (59)
1982 Engineering Handbook (59)
2001 Bennett, w/walking difficulties,
2001 Bennett, w/walking difficulties,
2001 Bennett, w/o walking difficulties,
2001 Bennett, w/o walking difficulties,
1993 data, Knoblauch, younger, design
2001 Bennett, for design (9)
2004 LA, problem intersections (58)
2003 data, Fitzpatrick, older, 106 data
2003 data, Fitzpatrick, younger, 2,335
1995 Coffin, older, midblock (12)
1993 data, Knoblauch, older, 2,378 data
2001 Older Pedestrian Handbook, less
2001 Traffic Control Devices Handbook
1993 data, Knoblauch, older, design (14)
1993 data, Knoblauch, younger, 2,081
1995 Coffin, older, intersection (12)
midblock signal (64)
midblock signal (9)
midblock signal (9)
intersection (9)
data points (14)
intersection (9)
data points
capable (63)
points (14)
points
(62)
(14)
Figure 23. Comparison of findings from previous studies for 15th percentile walking speed
(labels contain year of study or year data were collected if known, authors or abbreviation
of title, characteristics of study if relevant, and reference number in parentheses).
Conclusions as required by law). This section also describes an analysis of
street and traffic characteristics (e.g., speed limit, number of
Comparing the findings from this TCRP/NCHRP study with lanes, and traffic volumes) that influence motorist compliance
previous work resulted in the following recommendations: at marked crosswalks at unsignalized intersections. More
details are included in Appendix M.
· 3.5 ft/s (1.1 m/s) walking speed for the general population;
and
· If older pedestrians are a concern, use a 3.0 ft/s (0.9 m/s)
Summary of Motorist Yielding Rates
walking speed.
Tables 21 and 22 summarize the measured motorist yield-
ing data from both types of pedestrian crossings (general
Motorist Compliance
population and staged), including comparable evaluation
This section presents the study findings on the effectiveness data from the literature where available. The results are
of pedestrian crossing treatments at unsignalized intersections grouped into the three basic categories of pedestrian crossing
as measured by motorist compliance (yielding or stopping treatments used in the study. The range column in the table
Table 20. Walking speed by age groups for Knoblauch et al. and
TCRP/NCHRP studies.
Age Group Walking Speed (ft/s)
Knoblauch et al. TCRP/NCHRP
th
Sample 15 50th Sample 15th 50th
Size Percentile Percentile Size Percentile Percentile
Young 2081 4.02 4.79 2335 3.77 4.74
Old 2378 3.10 3.94 106 3.03 4.25
All 4459* 3.53* 4.34* 2441 3.70 4.72
*Calculated using values provided in Knoblauch et al. paper (14).
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Table 21. Summary of motorist yielding compliance from three sources
for red signal or beacon and active when present.
TCRP D-08/NCHRP 3-71 Study Other Studies
Compliance Staged Compliance General Compliance Literature
Pedestrian Crossing Population Pedestrian Review (from Table L-1)
Crossing
Crossing # of Range Average # of Range Average # of Range Average
Treatment Sites (%) (%) Sites (%) (%) Sites (%) (%)
Red Signal or Beacon
Midblock Signal 2 97 to 99% 4 91 to 95% NA NA NA
100 98
Half Signal 6 94 to 97% 6 96 to 98% 1 99 99%
100 100
HAWK Signal 5 94 to 97% 5 98 to 99% 1 93 93%
Beacon 100 100
Active When Present
In-Roadway NA NA NA NA NA NA 11 8 to 66%
Warning Lights 100
Overhead 3 29 to 47% 4 38 to 49% 10 13 to 52%
Flashing Beacon 73 62 91
(Pushbutton
Activation)
Overhead 3 25 to 31% 3 61 to 67% NA NA 74%
Flashing Beacon 43 73
(Passive
Activation)
Pedestrian 6 46 to 65% 4 72 to 74% NA NA NA
Crossing Flags 79 80
Notes: "NA" indicates that data were not collected or available in the literature.
The "Range" column represents the range of motorist yielding for all sites with the
treatment.
The "Average" column represents the average value of motorist yielding for all sites with
the treatment.
Table 22. Summary of motorist yielding compliance from three
sources for enhanced and/or high-visibility treatments.
TCRP D-08/NCHRP 3-71 Study Other Studies
Compliance Staged Compliance General Compliance
Pedestrian Crossing Population Pedestrian Literature Review (from
Crossing Table L-1)
Crossing # of Range Average # of Range Average # of Range Average
Treatment Sites (%) (%) Sites (%) (%) Sites (%) (%)
Enhanced and/or High-Visibility
In-Street
Crossing Signs
(25 to 30 mph 82 to 84 to 44 to
3 87% 3 90% 7 77%
[40 to 91 97 97
48 km/h]
Speed Limit)
High-Visibility
Signs and
Markings 10 to
2 17% 2 4 to 35 20% NA NA NA
(35 mph 24
[55 km/h]
Speed Limit)
High-Visibility
Signs and
Markings
1 61 61% 1 91 91% 1 52 52%
(25 mph
[40 km/h]
Speed Limit)
Median
6 7 to 75 34% 7 7 to 54 29% NA NA NA
Refuge Islands
Notes: "NA" indicates that data were not collected or available in the literature.
The "Range" column represents the range of motorist yielding for all sites with the
treatment.
The "Average" column represents the average value of motorist yielding for all sites with
the treatment.
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represents the range of average compliance values for the sites compliance rates as shown in Tables 21 and 22. The
with that treatment. If a site had less than 10 general popula- research team concluded that other factors (e.g., traffic
tion pedestrians crossing the street during data collection, the volume, roadway width, and street environment) were
compliance values were not included in summary statistics. affecting compliance rates. These factors are discussed in
The average column represents the average compliance rate more detail in Appendix L.
for all sites with that treatment.
The research team prepared these findings from Tables 21
and 22: Significant Differences in Treatment
Effectiveness
· The motorist compliance rates for staged pedestrians and As indicated in the previous section, many crossing treat-
general population pedestrians were in relatively close ments had wide ranges in the measured compliance rate (see
agreement for most crossing treatments. Only two crossing Figure 24). Thus, even though the average compliance may
treatments (total of four study sites) had motorist yielding be greater for some treatments, the wide range in compliance
rates with a greater than 10 percent difference between does not mean that one treatment is statistically more effec-
general population and staged pedestrians. At three Los tive than others. The research team tested statistical differ-
Angeles sites, the research team attributed the differences ences of compliance rates between the crossing treatments
to general population pedestrians who routinely stepped using two different methods:
off the curb while waiting, whereas staged pedestrians did
not step off the curb until motorists yielded. At a single
· Analysis of variance--determines whether the mean com-
Tucson site, the general population pedestrian flow was
pliance rates of the crossing treatments are statistically dif-
fairly heavy, which could lead to two possible explanations:
ferent and
(1) motorists were more likely to yield to larger groups
· Multiple comparisons test--uses Tukey's "honestly signif-
of pedestrians than the single staged pedestrian and (2) the
icant differences" (HSD) test to find out which crossing
larger groups of pedestrians could have been more
treatments have statistically similar mean compliance
assertive in claiming the crosswalk right-of-way. Because
rates.
the behavior of the staged pedestrians was consistent
among all sites, these compliance rates are used in further
analyses. The findings of the statistical analyses are summarized as
· Red signal or beacon treatments consistently perform well, follows:
with compliance rates above 94 percent. The research team
concluded that these treatments are effective because they · The three devices designated as red signal or beacon had
send a clear regulatory message (a red signal means "Stop") statistically similar mean compliance rates. These devices
to motorists that they must stop for pedestrians. Nearly all include the midblock signal, half signal, and HAWK signal
the red signal or beacon treatments evaluated were used on beacon. All three devices had average compliance rates
busy, high-speed arterial streets. greater than 97 percent. These statistical results validate the
· Pedestrian crossing flags and in-street crossing signs also research team's approach of grouping these devices into the
were effective in prompting motorist yielding, achieving 65 same "red signal or beacon" category.
and 87 percent compliance, respectively. However, many of · Many crossing treatments in the "active when present" and
these crossing treatments were installed on lower-volume, "enhanced and/or high-visibility" categories had compli-
two-lane roadways. It has been suggested that motorists are ance rates that were not statistically different than other
more likely to yield to pedestrians crossing narrow, low- treatments. Only three treatments were statistically differ-
volume and low-speed roadways. This is supported by the ent from others in these categories. The compliance rate for
difference in compliance for high-visibility signs and in-street crossing signs was statistically different than com-
markings. On streets with a 35-mph (55-km/h) speed pliance rates for high-visibility signs and markings and
limit, the average compliance rate was 17 percent; however, overhead flashing beacons (pushbutton activation). The
on streets with a 25-mph (40-km/h) limit, the average research team concluded that it may still be appropriate to
compliance rate was 61 percent (although only a single site differentiate between the "active when present" and
had this speed limit). "enhanced and/or high-visibility" treatments when dis-
· The measured compliance rates for many crossing treat- cussing function. However, the statistical results indicated
ments varied considerably among sites. For example, that nearly all treatments in these two categories did not
treatments in the "active when present" and "enhanced have statistically significant differences between the mean
and/or high-visibility" categories have a wide range of compliance rates.
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100%
90%
80%
70%
Motorist Yielding (%)
60%
50%
40%
30%
20% Maximum site value
Average of all sites
10%
Minimum site value
0%
Msig Half Hawk InSt Flag OfPb Refu HiVi OfPa
Treatment Type
Abbreviations: Msig=midblock signal; Half=half signal; Hawk=HAWK signal beacon; InSt=in-
street crossing signs; Flag=pedestrian crossing flags; OfPb=overhead flashing beacons (pushbutton
activation); Refu=median refuge island; HiVi=high-visibility signs and markings; OfPa=overhead flashing
beacons (passive activation)
Figure 24. Site average and range for motorist yielding by crossing treatment.
Street Characteristics That Influence Pedestrian crossing flags did not show a statistically differ-
Treatment Effectiveness ent mean compliance for locations with a different number of
lanes. The flags on two-, four-, and six-lane highways had sta-
Because of the wide range in measured compliance rates tistically similar compliance rates. Median refuge islands were
among sites, the research team hypothesized that other vari- the only treatment with statistically different compliance val-
ables were influencing the treatment effectiveness. For exam- ues based on the number of lanes.
ple, an in-street crossing sign installed on a wide, high-speed The bottom chart in Figure 25 regroups the data in the
arterial would likely produce a lower compliance rate than if top chart of Figure 25 by number of lanes. As seen in the
installed on a narrow, lower-speed collector street. The bottom chart of Figure 25 for four-lane highways, the red
research team performed a qualitative analysis and a statisti- devices have a much higher compliance rate than the other
cal analysis of covariance to find those factors that most non-red devices. All but one of the devices on a two-lane
affected the range in compliance rates. roadway performed at better than a 60-percent compliance
rate.
Effect of Number of Lanes The statistical analysis of covariance also indicated that the
number of lanes crossed was a statistically significant variable
The top chart in Figure 25 shows the motorist yielding by (at the 0.05 level) in predicting motorist yielding at treatments.
treatment type (major grouping) and number of lanes. For the
"red signal or beacon" devices, the number of lanes did not
affect performance. Within the study set, red devices were on
Effect of Speed Limit
two-, four-, and six-lane roadways. A compliance rate above 94
percent exists, regardless of the number of lanes on the facil- Figure 26 shows motorist yielding by treatment type and
ity. The half signal treatment had statistically the same com- speed limit.As seen in the top chart of Figure 26, in-street pedes-
pliance rate for both two and four lanes. The same result was trian crossing signs and overhead flashing beacons (pushbutton
true for the HAWK treatment on four- and six-lane roads. activation) appear to have an increase in compliance with an
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Grouped by Treatment Type
100%
90%
80%
70%
Motorist Yielding (%)
60%
50%
40%
30%
20% Maximum site value
Average of all sites
10%
Minimum site value
0%
OfPa (2)
OfPa (4)
OfPb (4)
HiVi (4)
Msig (4)
Flag (2)
Flag (4)
Flag (6)
Hawk (4)
Hawk (6)
Refu (2)
Refu (4)
Half (2)
Half (4)
InSt (2)
Treatment Type (Number of Lanes)
Grouped by Number of Lanes
100%
90%
80%
70%
Motorist Yielding (%)
60%
50%
40%
30%
20% Maximum site value
Average of all sites
10%
Minimum site value
0%
OfPa (2)
OfPa (4)
OfPb (4)
Flag (2)
Flag (4)
Flag (6)
HiVi (4)
Msig (4)
Refu (2)
Refu (4)
Hawk (4)
Hawk (6)
Half (2)
Half (4)
InSt (2)
Treatment Type (Number of Lanes)
Abbreviations: Msig=midblock signal; Half=half signal; Hawk=HAWK signal beacon; InSt=in-street
crossing signs; Flag=pedestrian crossing flags; OfPb=overhead flashing beacons (pushbutton activation);
Refu=median refuge island; HiVi=high-visibility signs and markings; OfPa=overhead flashing beacons
(passive activation)
Figure 25. Motorist yielding by crossing treatment and number of lanes.
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Grouped by Treatment Type
100%
90%
80%
70%
Motorist Yielding (%)
60%
50%
40%
30%
Maximum site value
20%
Average of all sites
10%
Minimum site value
0%
HiVi (25)
HiVi (35)
Half (35)
OfPa (30)
OfPa (35)
Msig (35)
Flag (25)
Flag (30)
Flag (35)
InSt (25 )
InSt (30 )
OfPb (30)
OfPb (35)
Refu (25)
Refu (30)
Refu (35)
Hawk (35)
Hawk (40)
Treatment Type (Speed Limit)
Grouped by Speed Limit
100%
90%
80%
70%
Motorist Yielding (%)
60%
50%
40%
30%
20% Maximum site value
Average of all sites
10%
Minimum site value
0%
OfPa (30)
OfPa (35)
OfPb (30)
OfPb (35)
HiVi (25)
HiVi (35)
Refu (25)
Refu (30)
Refu (35)
Hawk (35)
Hawk (40)
Msig (35)
Half (35)
Flag (25)
Flag (30)
Flag (35)
InSt (25)
InSt (30)
Treatment Type (Speed Limit)
Abbreviations: Msig=midblock signal; Half=half signal; Hawk=HAWK signal beacon; InSt=in-street
crossing signs; Flag=pedestrian crossing flags; OfPb=overhead flashing beacons (pushbutton activation);
Refu=median refuge island; HiVi=high-visibility signs and markings; OfPa=overhead flashing beacons
(passive activation)
Figure 26. Motorist yielding by crossing treatment and posted speed limit.
