I. PROBLEM NUMBER
II. PROBLEM TITLE
PEDESTRIAN ACCOMMODATION IN TRAFFIC SIGNAL SYSTEMS
III. RESEARCH PROBLEM STATEMENT
Increasing mobility and safety for pedestrians is a major issue on street systems, particularly in light of recent Federal focus on the Americans with Disability Act (ADA). In the near future, pedestrian timing requirements at all signalized intersections in the US are expected to increase due to upcoming revisions to the Manual on Uniform Control Devices for Streets and Highways (MUTCD; 1). The revised standards will reduce the assumed pedestrian travel speed to correspond more closely with observed walking speeds, yielding longer pedestrian crossing intervals. The changes may have trade-offs for both isolated and coordinated signal operations. While there are potential safety benefits for all intersection users, including pedestrians, bicyclists, and motor vehicles, there may be tradeoffs in terms of traffic congestion in some locations. Therefore, the modified guidelines highlight the importance of re-examining the concept of intersection efficiency. Today’s traffic signal systems need to provide safe and convenient operations for all types of roadway users, including pedestrians.
Specific issues that need to be addressed include but are not limited to the following, and are listed in two categories: pedestrian service and signal operations.
Pedestrian Service
- Overall pedestrian understanding of signal displays (WALK, FLASHING DON’T WALK [FDW]) and the relatively new countdown timer, and can their application be improved? Also, benefits in safety and efficiency of countdown timers.
- Under what conditions should pedestrian signals be actuated with push buttons, and do pedestrian signals always improve pedestrian safety?
- What is the potential for variable length ped crossing times for slower walkers using a “call extender” based on time the button is pushed, or other technologies?
- How might omission of a crosswalk on one leg affect pedestrian delay and safety?
- When should signalized mid-block crossings be provided along major arterials?
- Use of all-red signals for vehicles (exclusive pedestrian phases), and of pedestrian “head start” on concurrent walk intervals (leading pedestrian intervals).
- Conditions under which alternative pedestrian treatments may be more appropriate than providing a pedestrian phase at a traffic signal, such as underpasses.
- Special considerations for pedestrian crossings at intersections along elementary school walking routes and near senior centers or senior housing.
- Potential need for clearance time adjustments on streets with heavy bicycle volumes.
- Potential to include pedestrians in the on-going Vehicle-Infrastructure-Integration (VII) work, i.e., adding pedestrian sensing and treatment and changing the focus to “Vehicle-Infrastructure-Traveler-Integration.”
Signal Operations
- How will pedestrian timing changes impact users at intersections in terms of pedestrian access and delay, and traffic congestion? What percentage of intersections in an urban area will actually experience significant congestion due to timing adjustments, and how will systems of coordinated signals be affected? Impacts on motor vehicles, transit vehicles and pedestrians should be examined over a range of roadway types (from small intersections to large multi-lane intersections with turn lanes) in a variety of urban and suburban areas.
- What effects will pedestrian signal timing changes have on safety? Will there be more pedestrian crashes because of frustrated drivers, or will driver awareness increase and pedestrian safety improve? Will longer cycle lengths result in pedestrians crossing against the signal, or drivers running red lights thus increasing vehicle accidents?
- Pedestrian timing in coordinated signal timing plans, assuming: ped demand in all cycles and thus longer cycle lengths vs. no ped demand and taking a signal out of coordination when a ped call occurs (similar to a pre-emption call). Need to consider the trade-offs and develop application guidelines for the two approaches.
- Signal timing strategies and their effectiveness in mitigating pedestrian/vehicle conflicts, such as using a leading pedestrian interval, an exclusive (scramble) pedestrian phase, and dynamic protected/permitted left-turn signal displays.
- Full development of passive detection to cancel unnecessary calls, and to provide dynamic pedestrian clearance time yielding longer FDW for elderly, but shorter FDW for young (2).
- Ped timing with split phasing in a way that minimizes adverse effects on vehicle traffic.
IV. LITERATURE SEARCH SUMMARY
Current practice and most guidelines regarding pedestrian timing primarily focus on pedestrian speed and clearance time. In dealing with pedestrian timing and signal operations, practicing engineers have developed various techniques to address pedestrian needs. Some of the standard practice evolved during a time when controllers were much more limited in capabilities and flexibility than today. As an example of more recent research, Tian et al. (2000) demonstrated the advantages and disadvantages of the two basic timing approaches of assuming constant pedestrian demand vs. assuming only vehicle demands. The alternatives could impact coordination as described by the phenomena of early phase release with more stops for the first approach, and a signal going out-of-coordination and disrupted progression under the second approach.
Following are several references from a TRIS search. Complete citations are provided in Appendix A.
Pedestrian Operations and Safety
Misunderstanding of Right-Of-Way Rules at Various Pedestrian Crossing Types: Observational Study and Survey, 2007
Impact of Coordination Parameters on Pedestrian Operations in NEMA Controllers, 2007
New Methods to Identify and Rank High Pedestrian Crash Zones: An Illustration, 2007
Changes in Driver Behavior Resulting from Pedestrian Countdown Signals, 2007
Influence of Pedestrians' Entry Process on Pedestrian Delays at Signal-Controlled Crosswalks, 2006
Assessment of Pedestrian and Driver Behavior at Signalized Intersections with Countdown Pedestrian Signals, 2006
Safe Pedestrian Crossings for Children and Elderly, 2006
Development of Bicycle and Pedestrian Detection and Classification Algorithm for Active-Infrared Overhead Vehicle Imaging Sensors, 2006
Perceptions of Aggressive Driving Behavior Toward Non-vehicle Users, 2006
Crosswalk Confusion: Pedestrians and Drivers Need More Information, or Do They?, 2006
Is It Safe to Walk in the Sunbelt? Geographic Variation among Pedestrian Fatalities in the United States, 1999–2003, 2006
Intelligent Night Vision System: Nighttime Pedestrian Detection Assistance System, 2005
The Continuing Evolution of Pedestrian Walking Speed Assumptions, 2004
Challenges of Unfamiliar Signalized Intersections for Pedestrians Who Are Blind: Research on Safety, 2004
Bicycle and Pedestrian Detection, 2003
Time to Walk: Effectiveness of Educational Efforts about Pedestrian Signals, 2001
Young and Old -- A Study in Pedestrian Safety, 1989
Safety of Pedestrian Crossings at Signalized Intersections, 1987
Older Drivers and Pedestrians, 1986
Signal Timing with Pedestrians
Trade-Offs Between Vehicular and Pedestrian Traffic Using Micro-Simulation Methods, 2007
Recommended Walking Speeds for Timing of Pedestrian Clearance Intervals Based on Characteristics of the Pedestrian Population, 2006
Design and Performance Analysis of Pedestrian Crossing Facilities for Continuous Flow Intersections, 2005
Optimization for Pedestrian and Vehicular Delay in a Signal Network, 2005
Retiming an Arterial Street to Achieve Pedestrian Access and Safety Goals - We Don't Just Move Cars Anymore!, 2004
Managing Traffic in Minnesota: A Guide to Pedestrian Crossings, Traffic Signals, Signing and Speed Limits, 2003
Pedestrian Timing Alternatives and Impacts on Coordinated Signal Systems under Split-Phasing Operations, 2001
Pedestrian Clearance Intervals at Modern Intersections: Implications for the Safety of Pedestrians Who Are Visually Impaired, 2001
Pedestrian Head Start Signal Timing, 2000
Pedestrian Timing Treatment for Coordinated Signal Systems, 2000
Flexibility in Clearance-Interval Timing, 1999
Scramble and Crosswalk Signal Timing, 1998
Intersection Geometric Design and Operational Guidelines for Older Drivers and Pedestrians, Volume III: Guidelines, 1997
High-Volume Pedestrian Crosswalk Time Requirements, 1995
Safety Evaluation of School and Pedestrian Crossings, 1994
Evaluation of Innovative Pedestrian Signalization Alternatives, 1984
Effect of Pedestrian Signals and Signal Timing on Pedestrian Accidents, 1982
Urban Intersection Improvements for Pedestrian Safety--Volume III: Signal Timing for the Pedestrian, 1977
V. RESEARCH OBJECTIVE
The objective of this research is to document existing and develop new strategies for accommodating pedestrians at traffic signals and signalized arterials. The strategies should focus on balancing safety, pedestrian mobility and signal system efficiency. The effort will likely require consideration of safety impacts, field studies of both pedestrian and vehicle operations, and traffic simulation studies of various conditions. These will help identify key relationships and trade-offs. The result should be documentation and application guidelines for transportation agencies to better design and operate urban transportation systems, improving service quality for all road users.
VI. ESTIMATE OF PROBLEM FUNDING AND RESEARCH PERIOD
Recommended Funding:
$600,000
Research Period:
2-1/2 years
VII. URGENCY, PAYOFF POTENTIAL, AND IMPLEMENTATION
This research will address some of the urgent needs due to pending changes in the MUTCD for pedestrian accommodation policies at traffic signals. A clear understanding of the tradeoffs between safety, pedestrian mobility and signal efficiency can better guide transportation agencies in the design and operation of their urban transportation facilities. Results from the research should be directly implemented in the form of application guidelines to assist transportation engineers and policy makers in selecting best practices and strategies for pedestrian safety and access, plus system efficiency. The research may also improve methodologies used in analyzing signalized intersections and in developing coordinated signal timing plans with pedestrian considerations.
VIII. PERSON DEVELOPING THE PROBLEM
IX. PROBLEM MONITOR
X. DATE AND SUBMITTED BY
Date: September 14, 2007
REFERENCES
- A Notice of Proposed Rulemaking (Federal Register) is expected in October 2007 calling for formal change of MUTCD Section 4E.10 to reduce walking speed to 3.5 fps (with full crossing check @ 3.0 fps). See minutes of January 20, 2006 meeting, Attachment 1.
- Sandy Blvd, in Portland, OR has three intersections that have implemented (starting in 1998) pedestrian detection to lengthen/shorten ped time based on actual demand from pedestrian detection. Contact for details.
APPENDIX A - FULL REFERENCE CITATIONS
Pedestrian Operations and Safety
Misunderstanding of Right-Of-Way Rules at Various Pedestrian Crossing Types: Observational Study and Survey, 2007
Authors:Hatfield, Julie; Fernandes, Ralston; Job, R F Soames; Smith, Ken
Journal:Accident Analysis & Prevention, Vol. 39 No. 4
Corp. Authors/Publisher:Elsevier
Impact of Coordination Parameters on Pedestrian Operations in NEMA Controllers, 2007
Authors: Sunkari, Srinivasa R; Balke, Kevin N
Conference: Transportation Research Board 86th Annual Meeting
Corp. Authors/Publisher:Transportation Research Board
New Methods to Identify and Rank High Pedestrian Crash Zones: An Illustration, 2007
Authors:Pulugurtha, Srinivas S; Krishnakumar, Vanjeeswaran K; Nambisan, Shashi S
Journal:Accident Analysis & Prevention, Vol. 39 No. 4
Corp. Authors/Publisher:Elsevier
Changes in Driver Behavior Resulting from Pedestrian Countdown Signals, 2007
Authors:Huey, S. Brian; Ragland, David R
Conference:Transportation Research Board 86th Annual Meeting
Corp. Authors/Publisher:Transportation Research Board
Influence of Pedestrians' Entry Process on Pedestrian Delays at Signal-Controlled Crosswalks, 2006
Authors:Kruszyna, M; Mackiewicz, P; Szydlo, A
Journal:Journal of Transportation Engineering, Vol. 132 No. 11
Corp. Authors/Publisher: American Society of Civil Engineers
Assessment of Pedestrian and Driver Behavior at Signalized Intersections with Countdown Pedestrian Signals, 2006
Authors:Schattler, Kerrie L; Datta, Tapan K
Conference:ITE 2006 Technical Conference and ExhibitInstitute of Transportation Engineers
Corp. Authors/Publisher:Institute of Transportation Engineers
Safe Pedestrian Crossings for Children and Elderly, 2006
Authors:Leden, Lars; Garder, Per; Johansson, Charlotta
Journal:Accident Analysis & Prevention, Vol. 38 No. 2
Corp. Authors/Publisher:Elsevier
Development of Bicycle and Pedestrian Detection and Classification Algorithm for Active-Infrared Overhead Vehicle Imaging Sensors, 2006
Authors:Noyce, David A; Gajendran, Arunkumar; Dharmaraju, Raghuram
Journal:Transportation Research Record: Journal of the Transportation Research Board No. 1982
Corp. Authors/Publisher:Transportation Research Board
Perceptions of Aggressive Driving Behavior toward Non-vehicle Users, 2006
Authors:Sarkar, Sheila
Conference:Transportation Research Board 85th Annual Meeting
Corp. Authors/Publisher:Transportation Research Board
Crosswalk Confusion: Pedestrians and Drivers Need More Information, or Do They?, 2006
Journal:TrafficSafetyCenter Online Newsletter, Vol. 3 No. 4
Is It Safe to Walk in the Sunbelt? Geographic Variation among Pedestrian Fatalities in the United States, 1999–2003, 2006
Authors:Paulozzi, Leonard J
Journal:Journal of Safety Research, Vol. 37 No. 5
Corp. Authors/Publisher:Elsevier
Intelligent Night Vision System: Nighttime Pedestrian Detection Assistance System, 2005
Authors:Tsuji, Takayuki; Hashimoto, Hideki; Nagaoka, Nobuharu
Conference:12th World Congress on Intelligent Transport Systems
Corp. Authors/Publisher:ITS America
The Continuing Evolution of Pedestrian Walking Speed Assumptions, 2004
Authors:LaPlante, John N.; Kaeser, Thomas P.
Journal:ITE Journal, Vol. 74 No. 9
Corp. Authors/Publisher:Institute of Transportation Engineers
Challenges of Unfamiliar Signalized Intersections for Pedestrians Who Are Blind: Research on Safety, 2004
Authors:Bentzen, B L; Barlow, J M; Bond, T
Journal:Transportation Research Record No. 1878
Corp. Authors/Publisher:Transportation Research Board
Bicycle and Pedestrian Detection, 2003
Corp. Authors/Publisher: SRF Consulting Group, Incorporated; Federal Highway Administration; Minnesota Department of Transportation
Time to Walk: Effectiveness of Educational Efforts about Pedestrian Signals, 2001
Authors:Markowitz, F; Corbett, S
Conference:ITE 2001 Annual Meeting and Exhibit
Corp. Authors/Publisher:Institute of Transportation Engineers
Young and Old -- A Study in Pedestrian Safety, 1989
Journal:Forum Papers, Australasian Transport Research Forum, Vol. 2
Corp. Authors/Publisher:Queensland Department of Transport
Safety of Pedestrian Crossings at Signalized Intersections, 1987
Authors:Zaidel, D M; Hocherman, I
Journal:Transportation Research Record No. 1141
Corp. Authors/Publisher:Transportation Research Board
Older Drivers and Pedestrians, 1986
Authors:Anderson, R W G
Journal:Transafety Reporter, Vol. 4 No. 1
Corp. Authors/Publisher:TranSafety Incorporated; TranSafety, Incorporated
Signal Timing with Pedestrians
Trade-Offs between Vehicular and Pedestrian Traffic Using Micro-Simulation Methods, 2007
Authors:Ishaque, Muhammad Moazzam; Noland, Robert B
Journal:Transport Policy, Vol. 14 No. 2
Corp. Authors/Publisher:Elsevier
Recommended Walking Speeds for Timing of Pedestrian Clearance Intervals Based on Characteristics of the Pedestrian Population, 2006
Authors:Gates, Tim J; Noyce, David A; Bill, Andrea R; Van Ee, Nathanael
Journal:Transportation Research Record: Journal of the Transportation Research Board No. 1982
Corp. Authors/Publisher:Transportation Research Board
Design and Performance Analysis of Pedestrian Crossing Facilities for Continuous Flow Intersections, 2005
Authors:Jagannathan, Ramanujan; Bared, Joe G
Journal:Transportation Research Record: Journal of the Transportation Research Board No. 1939
Corp. Authors/Publisher:Transportation Research Board
Optimization for Pedestrian and Vehicular Delay in a Signal Network, 2005
Authors:Bhattacharya, Prabhati; Virkler, Mark R
Journal:Transportation Research Record: Journal of the Transportation Research Board No. 1939
Corp. Authors/Publisher:Transportation Research Board
Retiming an Arterial Street to Achieve Pedestrian Access and Safety Goals - We Don't Just Move Cars Anymore!, 2004
Authors:Kloos, W C; Peters, James M.; Rotich, W E
Conference:2004 Annual Meeting and Exhibit
Corp. Authors/Publisher:Institute of Transportation Engineers
Managing Traffic in Minnesota: A Guide to Pedestrian Crossings, Traffic Signals, Signing and Speed Limits, 2003
Corp. Authors/Publisher:Minnesota Department of Transportation
Pedestrian Timing Alternatives and Impacts on Coordinated Signal Systems under Split-Phasing Operations, 2001
Authors:Tian, Z Z; Urbanik, T; Engelbrecht, R; Balke, K
Journal:Transportation Research Record No. 1748
Corp. Authors/Publisher: Transportation Research Board
Pedestrian Clearance Intervals at Modern Intersections: Implications for the Safety of Pedestrians Who Are Visually Impaired, 2001
Authors:Barlow, J M; Franck, L; Bentzen, B L; Sauerburger, D
Journal:Journal of Visual Impairment & Blindness, Vol. 95 No. 11
Corp. Authors/Publisher: American Foundation for the Blind; American Foundation for the Blind
Pedestrian Head Start Signal Timing, 2000
Authors:Fleck, J
Conference:Compendium of Papers. Institute of Transportation Engineers 2000 District 6 Annual Meeting
Corp. Authors/Publisher:Institute of Transportation Engineers
Pedestrian Timing Treatment for Coordinated Signal Systems, 2000
Authors:Tian, Z.; Urbanik, T.; Kacir, K K; Vandehey, M A; Long, H
Conference: Proceedings of ICTTS 2000
Corp. Authors/Publisher:American Society of Civil Engineers (ASCE)
Flexibility in Clearance-Interval Timing, 1999
Authors:Parsonson, P S
Conference:Transportation Frontiers for the Next Millennium: 69th Annual Meeting of the Institute of Transportation Engineers
Corp. Authors/Publisher:Institute of Transportation Engineers
Scramble and Crosswalk Signal Timing, 1998
Authors:Virkler, Mark R
Journal:Transportation Research Record No. 1636
Corp. Authors/Publisher:Transportation Research Board
Intersection Geometric Design and Operational Guidelines for Older Drivers and Pedestrians, Volume III: Guidelines, 1997
Authors:Staplin, L; Harkey, D L; Lococo, K H; Tarawneh, M S
Corp. Authors/Publisher:Scientex Corporation; Federal Highway Administration
High-Volume Pedestrian Crosswalk Time Requirements, 1995
Authors:Virkler, Mark R; Elayadath, S; Saranathan, G
Journal:Transportation Research Record No. 1495
Corp. Authors/Publisher:Transportation Research Board
Safety Evaluation of School and Pedestrian Crossings, 1994
Authors:Mousssavi, M; Al-Turk, M; Ziettlow, L
Conference:Compendium of Technical Papers, 64th ITE Annual Meeting
Corp. Authors/Publisher:Institute of Transportation Engineers
Evaluation of Innovative Pedestrian Signalization Alternatives, 1984
Authors:Zegeer, C V; Cynecki, M J; Opiela, K S
Journal:Transportation Research Record No. 959
Corp. Authors/Publisher:Transportation Research Board
Effect of Pedestrian Signals and Signal Timing on Pedestrian Accidents, 1982
Authors:Zegeer, C V; Opiela, K S; Cynecki, M J
Journal:Transportation Research Record No. 847
Corp. Authors/Publisher:Transportation Research Board
Urban Intersection Improvements for Pedestrian Safety--Volume III: Signal Timing for the Pedestrian, 1977
Authors:Abrams, C M; Smith, S A
Corp. Authors/Publisher:JHK & Associates; Biotechnology, Incorporated
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