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|Federal Highway Administration > Publications > Public Roads > Vol. 63· No. 2 > Rural Road Safety: A Global Challenge|
Rural Road Safety: A Global Challenge
by Patrick Hasson
International Road Research at OECD
Each year, there are as many as 500,000 deaths and 15 million injuries worldwide as a result of road traffic crashes. This represents 1,400 fatalities and 41,000 injuries per day, and one-quarter of these are in the most highly developed countries. Depending upon the methodology used, the economic losses associated with these traffic fatalities and injuries can amount to anywhere between 1 percent and 4 percent of the gross domestic product in the developed countries. These numbers indicate that traffic safety remains an important public and social issue as well as an economic challenge.
Traffic safety has been a major theme of the road research program of the Organisation for Economic Co-operation and Development (OECD) for more than 30 years. OECD is an international organization of 29 of the world's most developed nations. OECD provides a setting in which to discuss and develop economic and social policy. The members compare experiences, seek answers to common problems, and work to coordinate domestic and international policies.
In 1968, OECD created the Road Transport Research (RTR) Program to provide regular interaction and exchange among national road researchers from OECD member countries. For the past 30 years, the program has operated on three-year cycles, having been renewed 10 consecutive times by the OECD Council. The most recent renewal occurred in December 1997. At that time, the title was changed to the Program of Research in Road Transport and Intermodal Linkages to better reflect a strategic framework in which roads are an integral part of the entire transport system with integrated seamless transport; however, the program title abbreviation RTR was retained. Road safety has been a long-standing feature of the RTR, and it remains central to the research program because of its worldwide significance.
Every three-year program of work includes "activity centers" to focus the RTR research effort. The activity centers have changed gradually over time to reflect the members' priorities. These focus areas are identified by the RTR Steering Committee, which is composed of senior road research and policy officials from the OECD countries. The 1998-2000 program of work has three activity centers:
Detailed descriptions of the current and past RTR program can be found on the OECD Web site (www.oecd.org).
Rural Road Safety Is a Global Concern
For each of these activity centers, the RTR Steering Committee elects to undertake specific research projects that address issues of relevance to a majority of the countries. Within this framework, the committee created an expert group, composed of representatives from 14 countries, to examine the rural road safety problems in the OECD countries and to propose strategies to reduce deaths and injuries resulting from traffic crashes on these roads.
One of the first tasks of the expert group was to quantify the rural road safety problem. Unfortunately, data documenting the rural road safety problem is inconsistent and, in some cases, unreliable among the OECD countries. Thus, it was not possible to make a clear assessment of injuries on rural roads; however, using data from the International Road Traffic Accident Database (IRTAD), the International Road Federation, and other sources, the group was able to determine that more than 75,000 people are killed each year on rural roads in OECD countries.
As figure 1 shows, rural road crashes result in more than 60 percent of all road fatalities in OECD countries. The socio-economic costs of rural road fatalities are approximately $120 billion per year. It is likely that personal injuries in rural road crashes are equally staggering in their number and cost.
Figure 2 shows the results of a similar analysis for the United States. As seen in this figure, rural roads that are not part of the Interstate Highway System have traditionally accounted for about 50 percent of the total fatalities on our nation's highways. In 1996, about 21,000 people lost their lives in rural road crashes. However, in the last five years, there has been some modest improvement. Although these statistics show that the situation in the United States is better than generally found in other OECD countries, they mask the fact that in the United States, the fatality rate per 100 million vehicle-miles traveled in rural areas is more than twice the rate in urban areas. This fact corresponds to the OECD findings that the risk of being killed on rural roads is generally higher per kilometer driven than on urban roads and four to six times higher than on freeways.
Rural road crashes are generally more severe than crashes on urban roads due to differences in operating speeds, road geometry, functionality, enforcement levels, and other factors. This accounts for the high proportion of rural road fatalities in relation to total road crash fatalities. In fact, the OECD countries have generally experienced an increase in the relative proportion of rural road fatalities as the total number of road crash fatalities during the same period has decreased. It can, therefore, be concluded that freeway and urban road safety improvements have been more successful and/or been given a higher priority than those on rural roads.
Fortunately, in the United States, urban and rural road safety improvements have been more balanced. Unfortunately, considering the overall relative risk of dying in a traffic crash, the number of fatalities on rural roads is still higher than should be expected given the relatively low level of traffic. This, in turn, implies that progress has not been as rapid as the situation dictates.
Another troublesome characteristic of the rural road safety situation in the United States is that 75 percent of the drivers involved in fatal crashes on rural roads are rural and small-town residents. Because one can surmise that the drivers in these crashes are generally familiar with the roads on which they are driving, this percentage drives home the important fact that the rural road safety problem is very much a local problem that deserves much greater attention by local public officials and residents.
The expert group concluded that the rural road safety problem is very serious and that all road safety indicators (size, risk, development over time) clearly call for decision-makers and the road safety community to give more attention to rural road safety problems. The group also found that explicit safety policies or targets designed for rural roads were generally lacking in most OECD countries, including the United States. Given this state of affairs, the rural road safety problem deserves a higher priority in future road safety policies without reducing the efforts directed at reducing crashes in urban areas.
Characteristics of Rural Road Safety
To ensure clear communication and consistency in its report, the expert group chose to define rural roads as those roads that are both outside urban areas and are neither freeways nor unpaved roads. The wide variety of principles and implementation practices used in road classification schemes obscures a clear representation of the size and nature of road safety problems and makes it difficult to compare rural road safety between countries.
In spite of these differences, it is apparent that at the international level as much as 75 percent of all crashes on rural roads fall into three categories: single-vehicle crashes (especially running off the road), head-on collisions, and collisions at intersections. This number is completely consistent with figures for the United States, which indicate that these three crash types account for as much as 79 percent of rural crashes.
Single-vehicle crashes constitute 35 percent (46 percent in the United States) or more of all fatal rural road crashes. This type of crash is the most prevalent because all three elements of the family of hazardous factors - driver behavior, the vehicle, and the road (infrastructure) - contribute to these crashes and increase their severity.
Head-on collisions make up nearly 25 percent (18 percent in the United States) of all fatal crashes on rural roads. Driver behavior and the infrastructure are the principal factors in these crashes.
Collisions at intersections account for about 20 percent (15 percent in the United States) of all fatal rural road crashes. Again, driver behavior and infrastructure are the key contributing factors to these types of crashes.
Rural road crashes are scattered over the entire rural road network. Under these circumstances, a pressing challenge for safety professionals is to understand their causes and the contributing factors. A main conclusion from the OECD analysis is that the rural road system itself has inherent characteristics that significantly contribute to the high number of crashes and the high risks associated with rural road travel.
In addition, crashes on rural roads do not generally possess the features that catch the attention of the general public or the media. In this regard, there is widespread belief that preventing rural road crashes is extremely complex by nature because rural road crashes are incidental, far-away events that are caused by unsafe individual behavior that cannot be influenced by proper road design or effective police enforcement. In other words, the scattered nature of rural road crashes leads many to believe that "the lonely driver is to blame." Although this might correctly describe what people think, the expert group identified substantial evidence to refute this view and to urge strong new actions to reduce the rural road safety problem.
Inappropriate and excessive speeds are important contributing factors in rural road crashes because rural roads generally have inconsistent design characteristics over their total length as well as problems in individual design elements. These inconsistencies occur on roads whose alignment and use evolved over time rather than roads specifically designed for their current use. Because of these inconsistencies, drivers must constantly adapt their speed to account for regularly changing situations and circumstances that increase the opportunities for human error and lead to higher risks for crashes. Therefore, the expert group concluded that the keys to improved road safety are driving at an appropriate speed and safe road and roadside design.
Speed variation caused by the presence of buses, heavy trucks, agricultural vehicles, mopeds, and bicyclists also generates higher crash risks on rural roads than on other types of roads. Aside from this, fatigue and alcohol/drug use are also key factors in rural safety.
Rural Road Safety Strategy
After considering the characteristics of rural road safety, the expert group agreed that rural road safety is completely different than freeway or urban road safety and thus requires a separate management approach. Such an approach is almost non-existent in OECD countries. Knowledge about safe rural road design is developing rapidly although it is still incomplete. A systematic research approach with generally accepted research methodologies and tools would markedly increase the speed of knowledge development as well as the reliability and usefulness of the results. Specific attention to safety as a basic design element in university-level road engineering courses would also help speed knowledge dissemination.
The expert group recommended that every OECD country should develop a rural road safety improvement strategy. They also recommended that each country should develop short-term, short- to medium-term, and long-term programs that are based on a sound analysis of the problems. Such plans must pay special attention to raising awareness about rural road safety within the general public and within the organizations of all key participants - government, peer groups, and others.
For short-term programs, it is advisable to develop and implement a speed management program in which speed-limit setting and speed enforcement (combined with a publicity campaign) are key components. Also, a trauma management system could be installed in the short term.
In the short- and medium-term programs, traditional infrastructure measures that emphasize investment in the quality of the rural road infrastructure must be chosen. Low-cost, effective, and efficient infrastructural measures - such as upgrading edge and center lines, installing reflective pavement markers and roadside delineation, providing advance warning, installing rumble strips, and facilitating safety knowledge transfer and training - that preferably fit into existing road maintenance programs are recommended. Targeted high-hazard or "black spot" programs have proved very effective in this regard.
Long-term programs should include intelligent transportation systems (ITS) among other measures.
Individual Safety Measures
Based on research and practices in the OECD countries, the expert group identified nearly 50 measures that can improve rural road safety. The report of the group provides extensive references for all of the suggested measures. A considerable number of these are low-cost measures.
Although a structural networkwide approach is required, there is a clear understanding that individual low-cost measures can contribute substantially to the safety of the rural road network. For example, individual safety measures that address infrastructure offer the most plentiful opportunities for safety enhancement on rural roads. Table 1 shows a variety of infrastructure-related measures that can be applied to address the most likely crash types on rural roads.
The experts strongly recommend that safety should receive explicit attention at every level of the process - from the decision to build or rebuild a road and through the planning, design, and construction stages to the operation and maintenance phases. The basis of a safe road design is a consistent, hierarchical road network in which each road category has a particular function to fulfill. Therefore, rural roads should be assigned a specific function rather than trying to cater to a varying mix of functions. Also, the design of the road should be consistent with the function and in accordance with the lowest functional use of the road.
"Forgiving" roadside concepts and roadside improvements in general were stressed because they can significantly reduce the severity of crashes. There is very high potential for improving overall safety by treating or removing roadside obstacles. Obstacle-free zones of between 4 and 10 meters are desirable if the road geometry and right-of-way will allow it. Finally, roadside safety information and training for local road managers and engineers contribute to better and more timely treatment of roadside hazards.
Because physically separating opposing traffic is a rather drastic and often impractical approach, the concept of conflict-free overtaking opportunities is one advantageous alternative. In addition, the combination of increasing lane width and shoulder width is the most effective approach for preventing a variety of crash types.
To reduce the number of intersection collisions, roundabouts are generally a safe solution. However, because roundabouts can be a relatively expensive alternative, the decision to install roundabout intersections must be based on a thorough analysis of the cost-effectiveness of this solution in comparison to others. Channelization as a remedial measure at existing ordinary intersections can be a cost-effective means - as can road lighting at intersections - to reduce the number of nighttime collisions.
The expert group suggests a number of ways to separate slow and fast traffic in order to address the issue of speed variance on rural roads.
As a final comment on infrastructure, safety assessments and safety audits should be undertaken when planning, designing, building, or maintaining roads to prevent crashes rather than respond to those that have already happened.
Police enforcement is especially important to deter inappropriate and excessive speed, which is a major contributor to rural road crashes. Effective enforcement with appropriate penalties, remedial driver training, and publicity can bring about long-term behavior modification of drivers. However, due to the vastness of the rural road network, enforcement using conventional means has very limited potential. Publicity campaigns in conjunction with targeted enforcement can increase the enforcement effects and contribute to a change in driving norms. Likewise, repeated enforcement creates a longer "halo effect" than a blitz campaign. Also, some randomness in enforcement can increase effectiveness and produce a longer halo effect. In addition, automated enforcement technologies that target the causes of the rural road crashes should be considered. Finally, the expert group suggests that a portion of the funds generated by enforcement should be earmarked for rural road safety enhancements.
Although intelligent transportation systems are promising, the full safety potential of ITS can be realized only through research that addresses the costs of these systems, specific technical issues, the human-machine interface, and institutional and political constraints. Nevertheless, a host of low-cost ITS measures that will be ready for deployment within the next three years could help to reduce the principal crash types on rural roads. Table 2 lists various ITS technologies and the time frames in which they will be available.
Because excessive speed is a major contributor to rural road crashes, the paramount ITS solutions are speed control technologies such as speed advisory systems and adaptive cruise control. Other near-term, low-cost measures include guiding lights and systems to monitor the driver and to warn of an upcoming intersection. Applications such as smart seat belts, smart air bags, and vehicle data recorders will be broadly available and can lessen the rural road safety problem. Decisions to apply higher cost measures must be made on a case-by-case basis.
Identifying the location of a crash is one of the key problems in responding to rural road crashes. The group cited several options to improve the situation. These options include improving road and milestone identification schemes, expanding the use of the global positioning system, and exploring possibilities for automated crash detection. A driver, passenger, or observer with a cellular telephone can help emergency response units by providing information about the crash and by directing the units more rapidly to the crash location.
Publicity campaigns that better inform the public about how to react at the scene of a crash in conjunction with more widespread first aid training can also help to improve trauma treatment onsite at the rural road crash. The group also recommends some common guidelines and standard procedures that local hospitals could adopt to improve trauma treatment.
The available information about rural road safety problems is inadequate to support appropriate policy and investment decisions. To improve rural road safety, unified methods are required for collecting and reporting crash data, identifying exposure measures and intervention levels, monitoring and evaluating countermeasures, and estimating cost-effectiveness and benefit-cost ratios of these countermeasures. With these unified methods, it would possible to build a sound basis for rational rural road safety policies.
The group highlighted the role and importance of valid and reliable data for the systematic evaluation of countermeasures. Research and the necessary dissemination of research findings can help to improve data quality and reliability. Benchmarking of rural road strategies may also help to improve effectiveness, but research is required to identify the appropriate benchmarks to examine and the means for measuring such benchmarks. The group also called for further research in safety strategies and several individual safety measures to rapidly improve safety on rural roads.
Rural road safety is a significant, ongoing problem. However, for many years, safety on rural roads has "taken a back seat" to the attention paid to the traffic safety problems in urban areas even though the fatality rate per mile (or kilometer) driven is greater on rural roads - in some OECD countries, as much as four to six times greater than the fatality rate on freeways. More than 60 percent of all road crash fatalities in the 29 OECD countries occur on rural roads. The loss of human life (about 75,000 people die on rural roads in these countries each year) and other socio-economic costs (approximately $120 billion per year) are staggering. That's why OECD convened an expert group to examine rural road safety problems and to suggest possible solutions to lessen the social and economic consequences of rural road crashes.
Because the rural road safety situation in the United States is much the same as in the other OECD countries, the recommendations of the expert group are relevant to the United States.
The expert group recommended that each country should establish a specific rural road safety strategy that includes short-term, medium-term, and long-term actions. Such a strategy should ensure that safety is considered at every stage of road development - from planning through design and construction to operations and maintenance. To ensure that the strategy is comprehensive in its vision and approach, the development and implementation of the strategy should involve all organizations and individuals who address road hazard factors, including the road, the driver, and the vehicle.
The expert group also identified and recommended nearly 50 individual safety measures in four areas - infrastructure, enforcement, trauma management, and ITS - that can make a difference in improving rural road safety. These safety measures should be included in action plans developed in the OECD countries.
The recommendations of the expert group are in line with some actions already taking place in the United States. The development of the Interactive Highway Safety Design Model (IHSDM), the Highway Safety Information System (HSIS), and the Advanced Rural Transportation System (ARTS) program are prime examples. However, it is still useful to ask some questions related to rural road safety in the United States.
How one answers these questions will reveal how well we have addressed safety on rural roads in the United States. The expert group felt that rural road safety has not always received the attention it deserves. However, if the recommendations of the expert group are adopted by the road safety organizations in the OECD countries, including the United States, and implemented in conjunction with national programs, they can bring about needed changes and save lives.
Members of the Expert Group Tasked to Examine Rural Road Safety Problems in OECD Countries
Copies of the final Expert Group report, entitled Safety Strategies for Rural Roads, are available and can be purchased from OECD. Either visit the OECD home page at www.oecd.org or contact Wolfgang Hübner, Head, Transport Division, OECD, 2 rue André Pascal, 75775 Paris, CEDEX 16, France (e-mail: email@example.com).
Patrick Hasson is the safety engineer in the Midwestern Resource Center of the Federal Highway Administration (FHWA). Hasson spent two years in the Road Transport Research Program at the Organisation for Economic Co-operation and Development (OECD) in Paris, France. At OECD, he was involved in a variety of international research projects focused on safety, infrastructure, and transport operations. Prior to these assignments, he worked in the FHWA Office of International Programs. He has a bachelor's degree in engineering from the University of Maryland and a master's degree in engineering from Cornell University.
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