Signalized Intersection Safety In Europe
Printable version of this report (2.1 mb)
List of Figures and Tables
1-1. Map of Europe.
1-2. Scan team members
1-3. Jake Almborg of American Trade Initiatives.
2-1. Pedestrian and bicycle traffic at signalized intersection in Stockholm, Sweden.
2-2. Pedestrian and bicycle crossings in Germany.
2-3. Responsibilities of Germany's accident commissions.
2-4. The Netherlands' primary principles to achieve sustainable safety.
2-5. Vehicle simulator to test extended amber timing in the United Kingdom.
3-1. Signalized intersection in Stockholm, Sweden.
3-2. Signalized intersection layout in Frankfurt, Germany.
3-3. Audible pedestrian signal head in Germany.
3-4. Distribution of signal cycle lengths used in the Netherlands.
3-5. Nearside signals in the Netherlands.
3-6. Diagram in controller cabinet at a four-leg intersection in the Netherlands.
3-7. Actuated signal layout for intersections with approach speeds under 35 miles per hour.
3-8. Layout of speed discrimination and extension configuration for speeds over 45 miles per hour.
3-9. Microprocessor optimized vehicle actuation (MOVA) traffic model.
3-10. Features of a fully signalized roundabout in the United Kingdom.
4-1. Detector layout and relationship for LHOVRA system.
4-2. Summary of before-and-after studies of implementation of LHOVRA system.
4-3. Report summarizing conversion to LED lighting in Stockholm, Sweden.
4-4. Pedestrian push button equipped with acoustic locator tone in Sweden.
4-5. Virtually raised crosswalks in Sweden.
4-6. Traffic signal with back plate in Germany.
4-7. Supplemental signal warning right-turning motorists about pedestrians.
4-8. Pole-mounted audible signal in Germany.
4-9. "Signal ahead" warning sign in the Netherlands.
4-10. Signal poles with high-contrast stripes.
4-11. Large back plate bordered by white stripe.
4-12. Colored pavement used to distinguish bike lanes in the Netherlands.
4-13. Photo enforcement camera for red-light running in the Netherlands.
4-14. Photo enforcement warning signs in the Netherlands.
4-15. Effectiveness of photo enforcement in Utrecht, Netherlands.
4-16. Variable message signs on approaches to high-speed intersections in the Netherlands.
4-17. Advance warning signs and speed tables at intersections in the Netherlands.
4-18. Nearside bicycle signals in the Netherlands.
4-19. Supplemental signing identifying bicycle and pedestrian crossings.
4-20. Countdown indicator for bicycle crossing.
4-21. Pedestrian countdown indicator on push button.
4-22.Zigzag pavement markings to warn motorists of a pedestrian crossing.
4-23. PUFFIN crossing in the United Kingdom.
4-24. Schematic layout of a PUFFIN crossing in the United Kingdom.
4-25. Schematic layout for a staggered PUFFIN crossing in the United Kingdom.
4-26. Yellow crosshatched intersection in the United Kingdom.
4-27. Restricted-turn sign.
5-1. Pedestrian refuge island in Germany.
5-2. Staggered pedestrian crossing in Germany
5-3. Dog bone roundabout in the Netherlands.
5-4. Turbo roundabout configuration in the Netherlands.
5-5. Comparison of conflict points between traditional and turbo roundabouts.
5-6. Delineated bicycle and pedestrian paths at roundabouts in the Netherlands.
5-7. Speed table in right-turn lane.
5-8. Schematic layout of a through-about intersection.
5-9. Schematic layout of a double through-about intersection.
5-10. Schematic of a high-capacity intersection.
6-1. MAAP GIS-based software to target high-accident locations
6-2. MAAP stick diagram used to graphically summarize accident statistics
Office of International Programs FHWA/US DOT (HPIP)
400 Seventh Street, SW
Washington, DC 20590
The contents of this report reflect the views of the authors, who are responsible for the facts and accuracy of the data presented herein. The contents do not necessarily reflect the official policy of the Department of Transportation.
The metric units reported are those used in common practice by the persons interviewed. They have not been converted to pure SI units because in some cases, the level of precision implied would have been changed.
The United States Government does not endorse products or manufacturers. Trademarks or manufacturers' names appear herein only because they are considered essential to the document.
The publication of this document was sponsored by the U.S. Federal Highway Administration under contract number DTFH61-99-C00005. awarded to American Trade Initiatives, Inc. Any opinions, options, findings, conclusions, or recommendations expressed herein are those of the authors and do not necessarily reflect those of the U.S. Government, the authors' parent institutions, or American Trade Initiatives, Inc.
This report does not constitute a standard, specification, or regulation
1. Report No.
2. Government Accession No.
3. Recipient's Catalog No.
4. Title and Subtitle
Signalized Intersection Safety In Europe
5. Report Date
6. Performing Organization Code
|7.Gene Fong, James Kopf, Philip Clark, Rick Collins, Richard Cunard, Ken Kobetsky, Nazir Lalani, Fred Ranck, Robert Seyfried, Kevin Slack, James Sparks, Rudolph Umbs, Stephen Van Winkle||8. Performing Organization Report No.|
9. Performing Organization Name and AddressAmerican Trade Initiatives
P.O. Box 8228
Alexandria, VA 22306-8228
10. Work Unit No.(TRAIS)
11. Contract or Grant No.
12. Sponsoring Agency Name and AddressOffice of International Programs
Office of Policy
Federal Highway Administration
U.S. Department of Transportation
13. Type of Report and Period Covered
|14. Sponsoring Agency Code|
15. Supplementary Notes
FHWA COTR: Hana Maier, Office of International Programs
More than a third of the intersection-related fatal crashes in the United States occur at signalized intersections. The Federal Highway Administration, American Association of State Highway and Transportation Officials, and National Cooperative Highway Research Program sponsored a scanning study of Sweden, Germany, the Netherlands, and the United Kingdom to review innovative safety practices in planning, designing, operating, and maintaining signalized intersections.
The delegation observed that highway safety improvements are a priority in the European countries visited, with an emphasis on reducing fatalities. Programs for intersection safety focus on reducing vehicle speed through innovative methods, using computerized signal timing optimization programs, and providing road users with consistent information.
The scanning team's recommendations for U.S. implementation include developing a model photo enforcement program to reduce red-light running, enhancing dilemma-zone detection at high-speed rural intersections, and promoting roundabouts as alternatives to signalized intersections. The team also recommends controlling vehicle speed through intersections with such techniques as speed tables, pavement markings, and changeable message signs.
17. Key Words
Signalized intersection, traffic control device, dilemma zone, actuated signal, roundabout, automated photo enforcement, speed table, PUFFIN crossing, geometric design, pedestrian safety
18. Distribution Statement
No restrictions. This document is available to the public from the Office of International Programs
FHWA-HPIP, Room 3325
19. Security Classif.
20. Security Classif.
21. No. of Pages
Form DOT F 1700.7 (8-72) Reproduction of completed page authorized
Signalized Intersection Safety in Europe
Prepared by the International Scanning Study Team:
Stephen Van Winkle
Center for Public Safety
American Trade Initiatives, Inc.
LGB& Associates, Inc.
Federal Highway Administration
U.S. Department of Transportation
American Association of State Highway
and Transportation Officials
National Cooperative Highway Research Program
of the Transportation Research Board
FHWA INTERNATIONAL TECHNOLOGY EXCHANGE PROGRAM
The Federal Highway Administration's (FHWA) International Technology Exchange Program accesses and evaluates innovative foreign technologies and practices that could significantly benefit U.S. highway transportation systems. This approach allows for advanced technology to be adapted and put into practice much more efficiently without spending scarce research funds to recreate advances already developed by other countries.
The main channel for accessing foreign innovations is the International Technology Scanning Program. The program is undertaken jointly with the American Association of State Highway and Transportation Officials (AASHTO) and its Special Committee on International Activity Coordination in cooperation with the Transportation Research Board's National Cooperative Highway Research Program Project 20-36 "Highway Research and Technology – International Information Sharing," the private sector, and academia.
FHWA and AASHTO jointly determine priority topics for teams of U.S. experts to study. Teams in the specific areas being investigated are formed and sent to countries where significant advances and innovations have been made in technology, management practices, organizational structure, program delivery, and financing. Scan teams usually include representatives from FHWA, State departments of transportation, local governments, transportation trade and research groups, the private sector, and academia.
After a scan is completed, team members evaluate findings and develop comprehensive reports, including recommendations for further research and pilot projects to verify the value of adapting innovations for U. S. use. Scan reports, as well as the results of pilot programs and research, are circulated throughout the country to State and local transportation officials and the private sector. Since 1990, FHWA has organized more than 50 international scans and disseminated findings nationwide on topics such as pavements, bridge construction and maintenance, contracting, intermodal transport, organizational management, winter road maintenance, safety, intelligent transportation systems, planning and policy.
The International Technology Scanning Program has resulted in significant improvements and savings in road program technologies and practices throughout the United States. In some cases, scan studies have facilitated joint research and technology-sharing projects with international counterparts, further conserving resources and advancing the state of the art. Scan studies have also exposed transportation professionals to remarkable advancements and inspired implementation of hundreds of innovations. The result: large savings of research dollars and time, as well as significant improvements in the nation's transportation system.
For a complete list of International Technology Scanning Program topics and to order free copies of the reports, please see the list contained in this publication, as well as Web site: www.international.fhwa.dot.gov or e-mail: email@example.com
FHWA International Technology Exchange Reports
International Technology Scanning Program:
Bringing Global Innovations to U.S. Highways
Signalized Intersection Safety in Europe (2003)
Managing and Organizing Comprehensive Highway Safety in Europe (2003)
European Road Lighting Technologies (2001)
Commercial Vehicle Safety Technology and Practice in Europe (2000)
Innovative Traffic Control Technology and Practice in Europe (1999)
Road Safety Audits – Final Report and Case Studies (1997)
Speed Management and Enforcement Technology: Europe and Australia (1996)
Safety Management Practices in Japan, Australia, and New Zealand (1995)
Pedestrian and Bicycle Safety in England, Germany, and the Netherlands (1994)
Planning and Environment
European Right-of-Way and Utilities Best Practices (2002)
Wildlife Habitat Connectivity Across European Highways (2002)
Sustainable Transportation Practices in Europe (2001)
National Travel Surveys (1994)
European Intermodal Programs: Planning, Policy, and Technology (1994)
Policy and Information
European Practices in Transportation Workforce Development (2003)
Emerging Models for Delivering Transportation Programs and Services (1999)
Acquiring Highway Transportation Information from Abroad (1994)
International Guide to Highway Transportation Information (1994)
Freight Transportation: The Latin American Market (2003)
Intelligent Transportation Systems and Winter Operations in Japan (2003)
Traveler Information Systems in Europe (2003)
Meeting 21st Century Challenges of System Performance Through Better Operations (2003)
Freight Transportation: The European Market (2002)
Methods and Procedures to Reduce Motorist Delays in European Work Zones (2000)
European Winter Service Technology (1998)
European Traffic Monitoring (1997)
Traffic Management and Traveler Information Systems (1997)
Snowbreak Forest Book – Highway Snowstorm Countermeasure Manual (Translated from Japanese) (1996)
Winter Maintenance Technology and Practices – Learning from Abroad (1995)
Advanced Transportation Technology (1994)
Contract Administration: Technology and Practice in Europe (2002)
Geometric Design Practices for European Roads (2001)
International Contract Administration Techniques for Quality Enhancement (1994)
Pavement Preservation Technology in France, South Africa, and Australia (2002)
Recycled Materials In European Highway Environments (2000)
South African Pavement and Other Highway Technologies and Practices (1997)
Highway/Commercial Vehicle Interaction (1996)
European Concrete Highways (1992)
European Asphalt Technology (1990)
Performance of Concrete Segmental and Cable-Stayed Bridges in Europe (2001)
Steel Bridge Fabrication Technologies in Europe and Japan (2001)
European Practices for Bridge Scour and Stream Instability Countermeasures (1999)
Geotechnical Engineering Practices in Canada and Europe (1999)
Advanced Composites in Bridges in Europe and Japan (1997)
Asian Bridge Structures (1997)
Bridge Maintenance Coatings (1997)
Northumberland Strait Crossing Project (1996)
European Bridge Structures (1995)
Geotechnology—Soil Nailing (1992)
All publications are available on the Internet at www.international.fhwa.dot.gov
About 25 percent of fatal crashes in the United States are intersection related. Of these, more than one-third occur at signalized intersections. Given this fact, increasing safety at signalized intersections is a priority for the Federal Highway Administration (FHWA), the American Association of State Highway and Transportation Officials (AASHTO), the Institute of Transportation Engineers (ITE), and many State departments of transportation (DOTs). Indeed, FHWA has identified intersection safety as one of three priority areas for attention, and AASHTO's Strategic Highway Safety Plan includes improving the design and operation of highway intersections as one of its 22 key emphasis areas.
To this end—improving signalized intersection safety—FHWA and AASHTO sponsored a scanning study in May 2002 to focus on innovative signalized intersection safety practices in Europe. The scanning team visited four countries: Sweden, Germany, the Netherlands, and the United Kingdom. The objective of the study was to identify safety practices and evaluate their applicability to the United States. Through meetings with representatives from each country, site visits, and field observations, the team identified programs and strategies that could work in the United States and potential barriers to their success. This report presents the scan team's observations, findings, and recommendations.
AREAS OF INTEREST
To provide the European hosts with an understanding of the scanning study's objectives and team members' interests in signalized intersections, the team identified six major areas of interest and developed questions accordingly:
Selecting, designing, installing, operating, and maintaining traffic control devices
Innovative traffic control devices
Innovative geometric designs
Processes and procedures for identifying problems and evaluating and selecting countermeasures
Low-cost safety improvements
Research projects focusing on safety
The team sent the questions to the host countries' officials in advance so they could conduct research.
GENERAL FINDINGS AND OBSERVATIONS
Overall traffic safety in Sweden is directed by a national policy called "Vision Zero," which has a goal of 50 percent reduction in highway fatalities. The Vision Zero concept is rooted in the belief that preventing highway fatalities is the responsibility of all agencies and entities involved in transportation, including engineers, highway officials, police, and others.
Safety—particularly of pedestrians and bicyclists—is of primary importance, while vehicle mobility is secondary. Traffic safety efforts focus on eliminating fatalities and irreversible-injury accidents and protecting vulnerable road users instead of just reducing overall accident rates. The focus is on reducing crash severity, not frequency. On the basis of this principle, the Swedish National Road Administration (SNRA) converted some signalized intersections to roundabouts, expecting that though the frequency of accidents may increase, the severity of those accidents may decrease, and sought to reduce intersection speed, especially where pedestrians, bicycles, and vehicles share the same space.
An intersection safety technique of note is a system called LHOVRA, in which a series of detectors line an intersection's approach. The detectors determine vehicle type and speed at various points along the approach and adjust the signal timing by increasing the yellow change and all red clearance intervals to minimize the number of vehicles caught in the dilemma zone. In other words, the strategy looks for an opportunity to transition when the dilemma zone is unoccupied. LHOVRA is most effective at high-speed rural intersections, particularly where heavy truck traffic is a safety concern. SNRA has completed before-and-after studies at intersections where LHOVRA has been implemented, and the results are promising. The studies showed that LHOVRA reduced conflicts by one third and cut red-light running from 4 percent of drivers to 1 percent.
Highway safety improvements are a priority in Germany and, as a result, the number of highway fatalities since the 1990 reunification has decreased dramatically. Safety priorities in Germany are similar to those in Sweden. Goals include the following:
Safety with an emphasis on reducing the severity rather than the number of crashes
Mobility throughout the network, including transit
Intersection and roadway traffic flow and operations
Traffic safety in Germany is a coordinated effort among local and national organizations. The country has about 500 federal and local accident commissions (called KEBU in Frankfurt) made up of local traffic authorities, civil engineering departments at universities, police, and traffic security wardens. These commissions are responsible for identifying high-accident locations, completing studies, implementing solutions, and monitoring the solutions for effectiveness.
Like other European countries, Germany places a high priority on bicycle and pedestrian traffic safety. In some cases, pedestrians and bicyclists are given priority over motorists.
Germany has successfully applied photo enforcement techniques to slow traffic
and reduce red-light running. German officials identified two key conditions
for successful application: First, the public must be aware that photo enforcement
measures are being used. Second, disobeying the posted speed or running a red
light must carry a substantial penalty. German speed-enforcement cameras are
highly visible, signs warn of photo enforcement, and public messages are broadcast
to make motorists aware that the equipment is being used. Germany's fine
structure varies for red-light running in a photo-enforced intersection, depending
on how late the motorist enters the intersection. If the motorist is only one
second late, he is fined $175 (considered low). Progressively later times mean
progressively larger fines. Preliminary observations and studies of photo enforcement
suggest a dramatic decrease in both the number and severity of accidents.
Other intersection-safety strategies include using highly visible signal back plates, changeable-message signs, audible crossing signals, and flashing warning lights to identify high-accident locations.
National safety goals guide the Netherlands' approach to intersection
safety. The National Traffic and Transport Plan has set goals of a 30 percent
reduction in fatalities and a 25 percent reduction in serious injuries by 2010.
The plan is based on three principles: First, the form of a traffic system
should be designed to follow the intended function and prevent unintended uses.
Second, the system should be homogeneous. And third, the system should be predictable
even to unfamiliar road users.
As in other European countries visited, heavy pedestrian and bicycle traffic is common at most signalized intersections in the Netherlands. The Dutch use special advanced indicators to warn pedestrians, bicyclists, and motorists of potential conflict situations. A noteworthy practice in the Netherlands, unlike in the United States, is to operate signals at a local, vehicle-actuated level. This limits the maximum signal cycle lengths and accommodates pedestrians, bicycles, and public transport. Occasionally, motorized traffic congestion issues are treated as secondary. Signal synchronization is easily compromised if demand exists for bicycles, pedestrians, or public transport on other approaches to the signal.
The Dutch program for intersection safety focuses on reducing vehicle speed and providing road users with clear, consistent information. Speed is controlled by several methods, including geometric design, speed-warning signs, speed tables, and an extensive and conspicuous use of photo enforcement.
The Dutch spend a sizable amount of money on traffic control, much more than the United States and the other three countries visited spend. They have three Freeway Management Centers in the Randstad that monitor freeways in Amsterdam, Rotterdam, The Hague, and Utrecht, with detectors in and variable message signs over each lane nearly every quarter of a mile. Nearly every spot near complex freeway interchanges is viewable by cameras, and each variable message sign can be controlled remotely. Two other Freeway Management Centers are located elsewhere in the country. The countrywide Traffic Information Center and Freeway Incident Management Center is located in Utrecht. In contrast, because of the local approach to traffic control, major cities like Amsterdam and Rotterdam do not employ an urban traffic management center.
The Dutch promote safety and focus on skilled driving from the start by setting the following requirements for obtaining a diver's license:
An average of 30 hours of hands-on training, with lessons costing the equivalent of U.S. $30 per hour.
A 50-question written exam on information taken from a 500-page driver's manual.
A 35-minute driving test that costs the equivalent of U.S. $163 to take. The test has a 70-percent failure rate, and applicants must take another 10 lessons before retaking the test.
The Dutch, like the Swedes and Germans, prefer roundabouts to signals. If an intersection is already signalized, they look first at converting it to a roundabout. To better accommodate pedestrians and bicyclists, roundabouts are designed with a single lane around the center island and the approaches are not flared. Vehicles approach at 90 degrees to the roundabout so they will slow down to 15 miles per hour or less, and a center refuge island is installed to allow pedestrians and bicyclists to cross the roadway in separate halves. In many cases, roundabouts are not able to deal with the heavy traffic streams.
Enforcement tolerance is set to 7 kilometers per hour for speed limits below 100 kilometers per hour, and 8 kilometers per hour at higher speeds. In urban areas with a speed limit of 50 kilometers per hour, a tolerance of 14 percent is used. On motorways with a speed limit of 120 kilometers per hour, speeding up to 6.7 percent is tolerated with no penalties.
The United Kingdom's national safety plan, "Tomorrow's Roads—Safer for Everyone," calls for a 40 percent reduction in total roadway fatalities and serious injuries, a 50 percent reduction in the number of children killed or seriously injured, and a 10 percent reduction in the slight-casualty rate. As in the other countries visited, the emphasis in the United Kingdom is on reducing accidents with serious consequences. National authorities are implementing the plan in partnership with local authorities, police, health services, industry, government departments, and road users.
The United Kingdom, like the United States, faces significant traffic congestion in metropolitan areas. It faces the challenge of maintaining a delicate balance among safety, mobility, and congestion in the design and operation of signalized intersections. The British have developed and implemented a number of computerized signal-timing-optimization software packages, such as microprocessor optimized vehicle actuation (MOVA) and optimized signal capacity and delay (OSCADY), to increase intersection capacity, reduce delay and queuing, and improve safety.
Pedestrian safety at signalized intersections is a high priority. To this end, a number of specialized pedestrian crossings such as PUFFIN (pedestrian user-friendly intelligent) and TOUCAN ("two can" cross) have been developed. And technologies such as passive infrared and microwave detection optimize both motorized and nonmotorized traffic operations at signalized intersections.
The United Kingdom uses photo enforcement extensively. At one field site 25 miles outside of London, the scan team was told that a motorist could encounter 16 cameras while driving from the site into London, each camera capable of issuing a violation. Theoretically, one speeding driver could receive 16 citations from a single trip.
The United Kingdom also has a point system, with 12 points in three years resulting in banning of a driver. Speed camera violations usually result in three points, though exceptional speed may result in more. Red-light camera violations result in three points.
The United Kingdom uses a uniform three-second yellow clearance at signals and displays a "starting yellow" of two seconds. The starting yellow comes on simultaneously with the red at the end of the red to indicate that the right-of-way is about to change. Conventional wisdom holds that the starting yellow helps drivers begin moving promptly on the green signal, maximizing junction capacity. Because the time is part of the safety inter-green time, omitting a starting yellow would increase the all-red time. The actual benefits of the starting yellow are being researched.
While not directly related to signals, the United Kingdom is using painted offset crosswalks in lieu of signals to force gaps in traffic. The offset crosswalk is designed to enable and force pedestrians to cross a two-way street one-half at a time, reducing the required gap and decision making in half. Since under some conditions signalization increases crashes, this strategy holds substantial promise.
On the basis of observations and findings in Sweden, Germany, the Netherlands, and the United Kingdom, the scan team developed five primary recommendations and several secondary ones. The primary recommendations include the following:
Develop a model photo enforcement program to reduce red-light running and control speed at high-accident signalized intersections.
Enhance dilemma-zone detection at high-speed rural intersections using MOVA, LHOVRA, and similar technologies.
Control vehicle speed through intersections using a combination of practices such as speed tables, pavement markings, automated photo enforcement, and changeable-message signs.
Promote roundabouts as alternatives to signalized intersections where traffic volumes allow as a way to manage the severity of collisions (taking into consideration that bicyclists are more vulnerable at roundabouts and that roundabouts make providing controlled pedestrian crossings more difficult).
Develop guidelines for improving pedestrian safety at signalized intersections using strategies such as PUFFIN and TOUCAN crossings, countdown indicators, and audible pedestrian signals.
Several scan team members also identified practices and programs that relate to their respective areas of expertise. These practices form the basis of the team's secondary recommendations, including introducing wider pavement markings, requiring a standard interval for all amber signals, and using countdown indicators for pedestrians and bicyclists.