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25 Table 12. Reproduction of HCM Exhibit 18-13: LOS criteria for pedestrians at unsignalized intersections. (23) LOS Average Likelihood of Risk-Taking Delay/Pedestrian(s) Behavior a A <5 Low B 5 to10 C > 10 to 20 Moderate D > 20 to 30 E >30 to 45 High F > 45 Very High a Likelihood of acceptance of short gaps. Findings From the Workshop ipants came from the West Coast, one came from the North- west, one came from the East Coast, and two came from the The MUTCD traffic signal warrants were developed with Midwest. "a careful analysis of traffic operations, pedestrian, and bicy- Each participant was provided with traffic/pedestrian data, clist needs, and other factors at a large number of signalized photographs, and a sketch of the eight intersections. The traf- and unsignalized intersections, coupled with engineering fic volumes were provided both in numeric format and plot- judgment." Research projects are periodically conducted to ted on a chart with the relevant curves for Signal Warrant 2 ensure that the traffic signal warrants reflect current opera- (4-hour vehicular volume) and Warrant 3 (peak hour). Tables tional and safety needs for the different user groups. In addi- were also provided listing the pedestrian volume (per hour tion to researching operational and safety needs, periodic and per street), intersection characteristics, and preliminary reviews of engineers' judgment toward the traffic signal war- results from an analysis using the eight warrants. rants (or toward proposed revisions to the traffic signal war- The group then drove to each site and reviewed the condi- rants) are needed. tions in the field. While in the field, the participants com- A study (55) in Texas recruited six DOT representatives, pleted a questionnaire for each site. After visiting the eight seven city representatives, and one consultant representative sites, the tour concluded at the original hotel with a 1-hour (all from Texas) to assess the appropriateness of installing a discussion. The discussion included comments on specific traffic signal because of pedestrian concerns at five loca- sites as well as general discussion on the pedestrian signal tions. The Texas study provided interesting findings; how- warrant. The participants were also asked to complete a gen- ever, only using engineers from one state was a concern. For eral questionnaire on the pedestrian signal warrant. this TCRP/NCHRP study, the timing and location of the 2004 Institute of Transportation Engineers Spring Confer- ence provided an opportunity to host a workshop on engi- Workshop Observations neering judgment evaluations of pedestrian signal warrants Details on the workshop and findings are included in that could include a more diverse geographic representa- Appendix J. Observations from the workshop are summa- tion. The workshop was held March 28, 2004, in southern rized below California. The workshop's objectives were to obtain opin- ions on The revised pedestrian signal warrant should consider the width of roadway being crossed. The width could either be The traffic signal warrants; the number of lanes or width of the roadway; however, if the How they related to specific locations; and number of lanes is being used, then a method to factor in the Potential treatments, including signalization, for the presence of bike lanes, parking lanes, and/or center turn lane selected intersections. needs to be included (given that all represent extra distance that a pedestrian must consider and cross). The judgment decision and gap determination become more difficult when Workshop Procedures a pedestrian is crossing a wider street. The Signal Warrant Engineering Judgment Evaluation Work- The pedestrian signal warrant needs to consider the shop was held March 28, 2004. Two tours were conducted as number of vehicles on the roadway along with the num- part of the workshop. In the first tour, seven engineers partici- ber of pedestrians. When there are many pedestrians and pated; six participated in the second. Each tour included an few cars, the pedestrians can "control" the crossing by engineer who was very familiar with the area and could answer becoming a steady stream of pedestrians with insufficient questions about local practices. Of the 13 participants, 9 partic- gaps for vehicles to enter (for example, a site where there