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7 Table 2. Purposes for pedestrian trips. (3) Purpose Percent Walking Percent of all Modes for That Purpose Traveling for That Purpose Personal/Family Business 43 46 Social/Recreational 34 25 School/Church/Civic 14 9 Earning a Living 7 20 Other 2 0 · Concerns for personal safety, Walking Speed · Failure to provide facilities to and from popular origins and destinations, Pedestrians have a wide range of needs and abilities. The · Inclement weather, MUTCD (1) includes a speed of 4.0 ft/s (1.2 m/s) for calcu- · Poor lighting, and lating pedestrian clearance intervals for traffic signals. The · Lack of facilities separated from the roadway. MUTCD also includes a comment that, where pedestrians routinely walk more slowly than normal or use wheelchairs in the crosswalk, a walking speed of less than 4.0 ft/s (1.2 m/s) Pedestrian Settings should be considered in determining the pedestrian clearance times. Other research studies have identified pedestrian Urban Areas walking speeds ranging from 2.0 to 4.3 ft/s (0.6 to 1.3 m/s) as Americans tend to walk more in urban cities with large pop- discussed in the following sections. The Institute of Trans- ulations occupying a small area, such as New York City, a city in portation Engineers (ITE) Design and Safety of Pedestrian which 70 percent of the population does not even own a car. Facilities cited walking speeds up to 8 ft/s (2.4 m/s) (7). Heavy traffic flow on roadways and limited or expensive park- ing facilities in these towns make walking seem the easier, faster, Pedestrians with Walking Difficulty and cheaper choice. In addition, many large cities with higher pedestrian populations (such as Boston; Washington, D.C.; A significant proportion (as much as 35 percent) of Chicago; and San Francisco) also offer access to efficient public pedestrians--children, older pedestrians, and persons with transportation systems such as subways that attract pedestrian disabilities--travels at a slower pace (8). Therefore, the users. Other cities (such as Portland, Oregon; Seattle, Washing- slower walking speeds of these groups could be considered ton; and Boulder, Colorado) have increased pedestrian popula- when determining pedestrian clearance intervals for traffic tions because of rigorous efforts by lawmakers and police signals in locations with a high percentage of pedestrians officials to make and enforce laws to encourage and protect with walking difficulties. An Australian Institute of Trans- pedestrian activity. Following are further explanations for why portation (9) study of intersection signalized crossing sites urban areas have high pedestrian use (4): identified the walking speeds of "pedestrians with walking difficulty" (irrespective of age) including older persons, · Traffic congestion is high. people with disabilities, and parents pushing a baby stroller · Origin and destination points are more numerous and and/or paying attention to a young child walking alongside, denser in concentration. a group which constituted 6 percent of the total sample size. · Shopping and services are more accessible to pedestrians. The summary of results is reproduced in Table 3. · Average trip distances are shorter. · Parking is too costly or unavailable. · Transit service is more readily available. Older Pedestrians · More pedestrian facilities are available. In the Guidelines and Recommendations to Accommodate Older Drivers and Pedestrians report (10), an assumed walking speed of 2.8 ft/s (0.9 m/s) is recommended for less capable Suburban and Rural Areas (15th percentile) older pedestrians with shorter strides, slower Pedestrian travel is higher in urban areas, but pedestrians gaits, and exaggerated "start-up" times before leaving the curb. can also be found in suburban and rural areas. Suburban and Mean start-up time (from the start of the Walk signal to the rural pedestrian trips are often associated with walking to moment the pedestrian steps off the curb and starts to cross) schools, school bus stops, or transit bus stops or for recre- was 2.5 s for older pedestrians, compared with 1.9 s for ational and leisure purposes. Fewer people walk to run younger ones (8). A study in Sweden (11) found that pedestri- errands and shop or to reach community services (4). ans aged 70 or older, when asked to cross an intersection very
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8 Table 3. Intersection crossing speeds of pedestrians with and without walking difficulty. (9) Average Standard 15th 50th 85th Speed, ft/s Deviation, Percentile, Percentile, Percentile, (m/s) ft/s (m/s) ft/s (m/s) ft/s (m/s) ft/s (m/s) Pedestrians with Walking 4.42 0.25 3.74 4.23 5.34 Difficulty (1.35) (0.08) (1.14) (1.29) (1.63) Pedestrians without Walking 5.58 0.50 4.27 5.25 6.69 Difficulty (1.70) (0.15) (1.31) (1.60) (2.04) All Pedestrians 5.35 0.48 4.07 5.12 6.43 (1.63) (0.15) (1.24) (1.56) (1.96) fast, fast, or at normal speed, considered fast to be less than (14). The presence of snow, ice, or slush on sidewalks and 4.3 ft/s (1.3 m/s). The comfortable speed was 2.2 ft/s (0.7 m/s) roads leads to ill-defined curbs, hidden potholes and obsta- for 15 percent, well below the standard often used. cles, greater amounts of glare and visual difficulties, and a A design walking speed of 3.3 ft/s (1.0 m/s) has been rec- greater chance of a slip or fall by a pedestrian (especially an ommended by Coffin and Morrall (12) at crossings used by older one) (8). All these conditions lead to reduced walking large numbers of seniors, on the basis of their observations of speeds during the winter (14). speeds of older pedestrians at three types of crossings. Speeds were greater at unsignalized intersections than where there Pedestrians at Signalized Midblock were signals. The older people in their study reported diffi- Crossings culty negotiating curbs and judging speeds of oncoming vehi- cles, as well as confusion with pedestrian walking signal A study of pedestrians with walking difficulty at pedestrian- indications (8). Results from other studies suggest that a actuated midblock signalized crossings on four-lane undi- design speed of 3.3 ft/s (1.0 m/s) may be too high. vided roads found an average crossing speed of 4.2 ft/s (1.3 m/s) and a 15th percentile speed of 3.3 ft/s (1.0 m/s), equal to the design speed of 3.3 ft/s (1.0 m/s) recommended by Pedestrians with Disabilities Australian and U.S. design guides for sites with higher popu- According to a study done in the United Kingdom in the lations of slower pedestrians (15). 1980s, about 14 percent of individuals over 15 years of age Table 5 summarizes crossing speeds for pedestrians with had physical, sensory, or mental handicaps (13). This popu- and without difficulty at midblock signalized crossing sites. lation has become much more mobile in recent decades, and Comparison of data in Tables 3 and 5 indicates that crossing increasing efforts have been made to meet their transporta- speeds are higher at signalized intersections, possibly because tion needs. As expected, the walking speeds for pedestrians of a perception of a less safe environment, especially as a with disabilities are lower than the average walking speed result of turning vehicle conflicts (9). assumed for the design of pedestrian crosswalk signal timing The authors noted that the results of all data for intersection (8). Table 4 shows some average walking speeds for those with and midblock crossing sites combined indicate that the design various disabilities and assistive devices. speed of 4.0 ft/s (1.2 m/s), commonly used for signal timing pur- poses, represents the 15th percentile crossing speed, with the cor- responding average crossing speed being 4.9 ft/s (1.5 m/s) (9). Weather Conditions A similar Australian study that investigated pedestrian Walking speeds would likely be slowed even further under movement characteristics at pedestrian-actuated midblock winter conditions resulting from snow and heavy footwear signalized crossings on four-lane undivided roads found the Table 4. Mean walking speeds for pedestrians with disabilities and users of various assistive devices. (8) Disability or Assistive Device Mean Walking Speed, ft/s (m/s) Cane or Crutch 2.62 (0.80) Walker 2.07 (0.63) Wheel Chair 3.55 (1.08) Immobilized Knee 3.50 (1.07) Below Knee Amputee 2.46 (0.75) Above Knee Amputee 1.97 (0.60) Hip Arthritis 2.24 to 3.66 (0.68 to 1.16) Rheumatoid Arthritis (Knee) 2.46 (0.75)