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From page 115... ... 113 APPENDIX B Detailed Synthesis of Literature Review of Treatments Roadway Design Features The following tables provide summaries of individual studies as follows: Treatment descriptions, location types where studied, study type, and the measured safety effects, which may include crashes, or behavioral/operational measures such as motorist speed, motorist yielding to pedestrians in crosswalks, pedestrian delay, pedestrian compliance with crosswalks, and other safety indicators. Narrow Lane Width Narrow Lane Width Location Type Study Type Measured Safety Effects Citation 1- Projects that increased the total number of through lanes by narrowing lanes 2- Projects to provide space for installation of center two-way left-turn lane -Urban arterial streets with posted speed limits of 45 mph or less -Roads with twolane undivided cross sections to roads with eight through lanes Observational evaluation of 35 improvement projects that used lane widths of 10 ft or less 1- Intersection crashes increased. Read the entire page →
From page 116... ... 114 Harwood, D.W., NCHRP Report 330: Effective Utilization of Street Width on Urban Arterials, Transportation Research Board, National Research Council, Washington, D.C., 1990, 55 pp. Road Diet Road Diet Location Type Study Type Safety Effects Citation -Most sites had reductions from four to three lanes. Read the entire page →
From page 117... ... 115 Knapp, K., B Chandler, J Read the entire page →
From page 118... ... 116 Raised Medians/Median Islands Location Type Study Type Safety Effects Citation Pedestrian refuge islands Two signalized intersections in urban San Francisco, CA Observational before and after analysis of behavioral effects -No significant impacts of pedestrian refuges on driver yielding, on pedestrian–vehicle conflicts, nor on the proportion of trapped pedestrians at two urban, signalized intersections -An increase in crossing delay at one of the two intersections studied Pécheux et al. Read the entire page →
From page 119... ... 117 References for Raised Medians and Pedestrian Median Islands Bacquie, R Read the entire page →
From page 120... ... 118 References for Raised Crosswalk/Speed Table Huang, H.F. Read the entire page →
From page 121... ... 119 van Hengel, D., "Build It and They Will Yield: Effects of Median and Curb Extension Installations on Motorist Yield Compliance," Transportation Research Board 92nd Annual Meeting Compendium of Papers, Paper No. Read the entire page →
From page 122... ... 120 Thomas, L., R Srinivasan, M Read the entire page →
From page 123... ... 121 Enhanced Illumination at Crossings Enhanced Illumination Location Type Study Type Safety Effects Citation Adding intersection illumination U.S. sites Meta-analysis on multiple studies -42% reduction in pedestrian nighttime crashes -This countermeasure is included in the Highway Safety Manual, with a caution that the adjusted standard error measurement is from 0.2 to 0.3. Read the entire page →
From page 124... ... 122 Traffic Control Devices High-Visibility Crosswalks High-Visibility Crosswalk Markings Location Type Study Type Safety Effects Citation High-visibility crosswalk markings Urban -- 72 sites, New York City Two-group pretest/ posttest using ANCOVA modeling to account for regression to the mean effect Before -- 5 years before crash data After -- 2 years after crash data After adjusting for comparison group (to account for potential regression to the mean) : -Statistically significant reduction of 48% in pedestrian crashes (CMF of 0.52; 0.17 s.e.) Read the entire page →
From page 125... ... 123 High-Visibility Crosswalk Markings Location Type Study Type Safety Effects Citation Strong yellow green (SYG) crosswalk markings; SYG plus speed feedback: "The school safety program elements included school crossing warning signs on the approach to and at every intersection, 20 mph during School Hours When Children Are Present speed limit signs on every surrounding street, speed humps on the local streets around the school (at least in the 660-ft blocks) Read the entire page →
From page 126... ... 124 Iragavarapu, V., K Fitzpatrick, and S.T. Read the entire page →
From page 127... ... 125 Advance Stop/Yield Location Type Study Type Safety Effects Citation Flashing beacons. Advance yield line markings with white background "Yield Here to Pedestrians" signs, fluorescent yellow-green "Yield Here to Pedestrian" signs (no markings) Read the entire page →
From page 128... ... 126 Van Houten, R Read the entire page →
From page 129... ... 127 Advance Stop/Yield Location Type Study Type Safety Effects Citation "Yield-to-Pedestrian" channelizing devices placed on the centerline of a roadway in advance of marked crosswalks Five locations each in four community types in Pennsylvania: urban, suburban, small city, and college town. Sites included both unsignalized intersections and midblock locations. Read the entire page →
From page 130... ... 128 Advance Stop/Yield Location Type Study Type Safety Effects Citation In combination with PHB Same study as above, but at two sites at suburban and urban locations in Detroit that had a PHB and in-street sign Same as above, but with PHB comparison At the suburban site, motorist yielding was 1% in the crosswalk-only condition. The addition of one in-street sign was associated with motorist yielding of 37%, and the use of the gateway treatment was associated with motorist yielding of 72%. Read the entire page →
From page 131... ... 129 Pedestrian Warning Signs Ped Warning Signs Treatments Location Type Study Type Safety Effects Citation Pedestrian warning signs Sites in central North Carolina Pre/post-treatment study of observational behavioral effects The use of this new sign was associated with increased numbers of cars that slowed down or stopped for pedestrians, although there was no decrease in conflict events following sign installation Clark et al. Read the entire page →
From page 132... ... 130 Van Houten, R., K Healey, J.E.L. Read the entire page →
From page 133... ... 131 Overhead or Roadside-Mounted Flashing Beacons Overhead/Roadside Beacons Location Type Study Type Safety Effects Citation Pedestrian-activated flashing beacons Two crosswalks; urban and suburban sites in Dartmouth, Nova Scotia Experimental: two strategies for increasing the percentage of motorists yielding to pedestrians at crosswalks equipped with pedestrianactivated flashing beacons. One strategy involved adding an illuminated sign, with the standard pedestrian symbol next to the beacons. Read the entire page →
From page 134... ... 132 References for Overhead or Roadside-Mounted Flashing Beacons Hua, J., N Gutierrez, I Read the entire page →
From page 135... ... 133 RRFB Location Type Study Type Safety Effects Citation RRFB One four-lane site at the intersection of Pinellas trail crossing in St. Petersburg, FL. Read the entire page →
From page 136... ... 134 RRFB Location Type Study Type Safety Effects Citation RRFB Six locations in Calgary, Canada. Traffic volumes ranged from 4,800 to 14,600 vpd, and streets had from one to five lanes. Read the entire page →
From page 137... ... 135 Van Houten, R., R Ellis, and E Read the entire page →
From page 138... ... 136 References for Pedestrian Hybrid Beacon Fitzpatrick, K., et al., TCRP Report 112/NCHRP Report 562; Improving Pedestrian Safety at Unsignalized Crossings, Transportation Research Board of the National Academies, Washington, D.C., 2006, 109 pp. Fitzpatrick, K., M Read the entire page →
From page 139... ... 137 References for Install Traffic Signal Without Pedestrian Countdown Timer Chen, L., C Read the entire page →
From page 140... ... 138 Traffic Signal with PCS Location Type Study Type Safety Effects Citation Traffic signal with pedestrian countdown signal Reanalysis of Camden et al. Read the entire page →
From page 141... ... 139 Traffic Signal with PCS Location Type Study Type Safety Effects Citation Increased pedestrian crossing time Implemented at 244 intersections in New York City; 1,173 untreated comparison intersections 5 years of before period crashes and 2 years of after period crashes were analyzed. Same methods as Chen, Chen, and Ewing (2014) Read the entire page →
From page 142... ... 140 Traffic Signal with PCS Location Type Study Type Safety Effects Citation Impact of PCS (pedestrian countdown timers) Eight large intersections in south Florida (19,000– 65,000 vehicles per day) Read the entire page →
From page 143... ... 141 References for Install Traffic Signal with Pedestrian Countdown Signal (PCS) Camden, A., R Read the entire page →
From page 144... ... 142 Leading Pedestrian Interval (LPI) LPI Location Type Study Type Safety Effects Citation Leading pedestrian interval Multiple sites in New York City Evaluation of the LPI on pedestrian crash statistics. Read the entire page →
From page 145... ... 143 King, M.R., "Calming New York City Intersections," Transportation Research Circular E-C019: Urban Street Symposium Conference Proceedings, Dallas, Tex., June 28–30, 1999, I-3, pp. Read the entire page →
From page 146... ... 144 NTOR Location Type Study Type Safety Effects Citation "No Turn on Red" Restrictions 26 sites in the Province of Quebec where RTOR was authorized for a period of 9 months Two-part pilot study: Part 1 -- observing driver behavior; Part 2 -- collecting data from a number of U.S. and Canadian agencies concerning the effect that RTOR had on safety and on traffic operations -In most cases, RTOR does not pose a danger to motorists, cyclists, or pedestrians. Read the entire page →
From page 147... ... 145 References for "Right Turn on Red" (RTOR) Restrictions Clark, J.E., S Read the entire page →
From page 148... ... Abbreviations and acronyms used without deﬁnitions in TRB publications: A4A Airlines for America AAAE American Association of Airport Executives AASHO American Association of State Highway Officials AASHTO American Association of State Highway and Transportation Officials ACI–NA Airports Council International–North America ACRP Airport Cooperative Research Program ADA Americans with Disabilities Act APTA American Public Transportation Association ASCE American Society of Civil Engineers ASME American Society of Mechanical Engineers ASTM American Society for Testing and Materials ATA American Trucking Associations CTAA Community Transportation Association of America CTBSSP Commercial Truck and Bus Safety Synthesis Program DHS Department of Homeland Security DOE Department of Energy EPA Environmental Protection Agency FAA Federal Aviation Administration FAST Fixing America's Surface Transportation Act (2015) FHWA Federal Highway Administration FMCSA Federal Motor Carrier Safety Administration FRA Federal Railroad Administration FTA Federal Transit Administration HMCRP Hazardous Materials Cooperative Research Program IEEE Institute of Electrical and Electronics Engineers ISTEA Intermodal Surface Transportation Efficiency Act of 1991 ITE Institute of Transportation Engineers MAP-21 Moving Ahead for Progress in the 21st Century Act (2012) Read the entire page →
From page 149... ... TRANSPORTATION RESEARCH BOARD 500 F ifth S treet, N .W . W ashing to n, D .C . Read the entire page →

From page 115...

... 113 APPENDIX B Detailed Synthesis of Literature Review of Treatments Roadway Design Features The following tables provide summaries of individual studies as follows: Treatment descriptions, location types where studied, study type, and the measured safety effects, which may include crashes, or behavioral/operational measures such as motorist speed, motorist yielding to pedestrians in crosswalks, pedestrian delay, pedestrian compliance with crosswalks, and other safety indicators. Narrow Lane Width Narrow Lane Width Location Type Study Type Measured Safety Effects Citation 1- Projects that increased the total number of through lanes by narrowing lanes 2- Projects to provide space for installation of center two-way left-turn lane -Urban arterial streets with posted speed limits of 45 mph or less -Roads with twolane undivided cross sections to roads with eight through lanes Observational evaluation of 35 improvement projects that used lane widths of 10 ft or less 1- Intersection crashes increased.