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Public Roads - Winter 2022

Winter 2022
Issue No:
Vol. 85 No. 4
Publication Number:
Table of Contents

Applying a Safe System Approach Across the Globe

by Matts-Åke Belin, Anders Hartmann, Mari Svolsbru, Blair Turner, and Michael S. Griffith
"Country maps of Sweden, Australia, and Norway, with Oslo pinpointed, against a road background with a double yellow line and a single white line. Photo illustration by FHWA. Highway image: © Andrey Kuzmin / Country images: © daboost /"
International countries and cities have successfully incorporated the Safe System Approach to improve road safety, including Sweden, Australia, and Oslo, Norway.

The United States can benefit from examining how other countries and international cities have incorporated the Safe System Approach to improve road safety. The following are success stories, insights, and lessons learned from two countries—Sweden and Australia—and one city—Oslo, Norway—in advancing the Safe System Approach.

Vision Zero in Sweden: A Road Safety Policy Innovation 

In 1997, the Swedish Parliament adopted Vision Zero. Since then, its success has spread internationally. Vision Zero has not only attracted interest in the transportation sector but in other sectors of Swedish society such as fire safety, patient safety, occupational accidents, and suicide prevention. Although many associate the Swedish version of Vision Zero with a strong ethical imperative and the long-term goal to eliminate fatalities and serious injuries, the strategy is much broader than that.

Vision Zero is a public policy that offers a new perspective on road safety problems and their causes, appropriate overall solutions that need to be implemented, and a new division of responsibilities in order to create a safe system. In short, the Swedish Vision Zero is both a new long-term goal and a new overall strategy that has forced Sweden to substantially transform its daily road safety business through the implementation of the Safe System Approach.

Control for Harmful Energy 

According to Vision Zero, the principal reason that people die or are seriously injured on the roads is that the kinetic energy to which people are exposed to in a crash exceeds the energy that the human body can withstand. The Vision Zero strategy rests on the research that well-known American road safety expert William Haddon conducted in the 1960s. Knowledge about energy forces and tolerance has largely served as a basis for the development of the passive safety characteristics of vehicles and for the development of different protection systems such as child safety seats, helmets, and seat belts.

The adoption of Vision Zero as a public policy has increased scientific knowledge about kinetic energy, which has provided an important foundation to develop a sub-component in the transportation system—namely the vehicle. Based on this design parameter, many transportation professionals suggest that the risk for different crash types should set the maximum speed limit. For example, in a situation in which risks exist for crashes with cars and vulnerable, unprotected road users such as pedestrians and bicyclists, the speed limit should not be higher than 20 miles (approximately 30 kilometers) per hour, and for risks of head-on collisions (such as cars to cars), at a speed not higher than 50 miles (approximately 80 kilometers) per hour.

From Policy to Implementation 

To paraphrase a quote from social scientist Kurt Lewin, “There is nothing more practical than a good [policy] theory.” The “policy” of Vision Zero must be translated into concrete actions. However, to go from policy intentions to sound policy outcomes in a complex world is difficult. Fortunately, Sweden put theory to action and based daily road safety work on Vision Zero. The nation adopted Vision Zero as a national policy focus throughout its entire transportation system. Vision Zero has influenced vehicle safety, road environment in cities, highways, and road user behavior. Vision Zero has also changed the way that Sweden organizes and governs transportation projects in both rural and urban settings.

Urban Environment 

In urban areas in Sweden, transportation safety is largely concerned with conflicts between protected and unprotected road users in which the most important determining factor is the unprotected road users’ tolerance level against impact forces. Although the knowledge is still not definitive, when new published research emerges, Sweden plans to adjust its recommended speed limits. So far, 20 miles (approximately 30 kilometers) per hour for unprotected road users seems to be an appropriate tolerance level. If the road owners plan for conflicts between protected and unprotected road users, they need to strive for energy levels less than 20 miles (approximately 30 kilometers) per hour. This tolerance level could become an international standard.

There are two main types of interventions within urban areas: physical separation and speed controlling. Physical separation through sidewalks, bridges, tunnels, bicycle lanes, and special areas only for pedestrians and cyclists eliminates conflicts between unprotected road users and vehicles. This type of intervention is appropriate when the motorized traffic demands high mobility. In areas where pedestrian and cyclist mobility constitute a priority and in areas with mixed traffic, the interventions need to control the speeds below 20 miles (approximately 30 kilometers) per hour. Several traffic-calming interventions such as speed bumps and roundabouts have proved effective. Promising vehicle technologies include intelligent speed adaption systems and automatic pedestrian detection and braking systems.

"A 3D rendering of a pedestrian positioned in front of a parked van attempting to cross a road as a vehicle stops alongside the parked van due to its pedestrian detection system. Photo Source: © Chesky /"
Promising vehicle technologies include automatic pedestrian detection and braking systems.

Rural Area: The 2+1 Roads

Sweden contains a large rural road network. Parts of the road network with high-traffic volume have been rebuilt over the years to become modern motorways. Because of the nation’s small population, Sweden built roads 43 feet (approximately 13 meters) wide, a type of “cheap” motorway, during the 1970s and 1980s. These roads were straight with high visibility, and the risk for crashes calculated per mile driven was low. The roads were also built with grade-separated intersections. Although deemed not justifiable to convert to motorways, these rural roads accommodated heavy traffic volume with a speed limit of 70 miles (approximately 110 kilometers) per hour. Even though the risk of crashes was small on these kinds of roads, those that did happen were typically severe. The traditional approach to this problem meant dissemination of information to the public about the risks, enhancing driver education, and to some extent increasing police enforcement—the perception being that a change in motorist behavior was the solution. But these strategies didn’t work.

When Sweden adopted Vision Zero, these rural parts of the road network came under scrutiny. A small proportion of the Swedish road network represented a large percentage of the number of fatalities and serious injuries, so action needed to be taken. Upgrading roads to motorways would address the problem of head-on collisions but would be expensive. At that time—the late 1990s—in Sweden, it was estimated that building a motorway would cost approximately 1 billion Swedish krona (approximately U.S. $116 million) per saved life.

Another alternative was to lower the speeds. Just as unprotected road users have a certain tolerance against external violence, so does a belted passenger in a modern car—about 50 miles (approximately 80 kilometers) per hour. However, it would likely be impractical to get Swedish road users to comply with that speed limit on high standard roads, and these roads are important from a mobility perspective.

Consequently, Sweden came up with a new solution, an innovation called “2 + 1 roads.” Basically, a 2 + 1 road is a three-lane road that consists of two lanes in one direction and one lane in the other, alternating every few kilometers to enable passing. This plan, especially in the beginning stages of implementation, proved to be a cost-effective solution to a major road safety problem, estimated to cost 30 million Swedish krona (about U.S. $3.5 million) per saved life. After some initial resistance, especially among the road builders, the country carried out a 2 + 1 road program. Today, Sweden contains about 2,000 miles (more than 3,000 kilometers) of these roads, and the number of fatalities decreased by 79 percent on approximately 1120 miles (or 1,800 kilometers) of these 2 + 1 roads built that were evaluated with data from 1998 to 2007. The 2 + 1 road illustrates a successful application of a Vision Zero approach.

"A 2 + 1 road in Sweden which is a three-lane road consisting of two lanes in one direction and one lane in the other, alternating every few kilometers to enable passing. Photo Source: © Lars Ekman."
This is an example of a 2+1 road in Sweden.

From Implementation to Result 

The number of road fatalities per million inhabitants has declined overall in Sweden over the past two decades. In 1999, the Swedish government launched an 11-point program for Vision Zero, and further implemented several interventions including traffic calming in urban areas, 2 + 1 roads, a new speed limit system, and traffic safety camera programs. In 2009, Sweden initiated a large organizational reform work in the transportation sector, guided by at least three important principles: an integrated transportation system, strict government mandate, and privatization of certain functions such as maintenance and infrastructure construction. In 2009, Sweden formed the Swedish Transport Agency (STA), which regulates and carries out inspection activities of all transport modes. The STA oversees plans for the whole transportation system and established the building and maintaining of road and railway infrastructure beginning in 2010.

"A line graph depicting the number of deaths in road traffic crashes per 100,000 population in Sweden from 1997–2020, from a high of almost seven to a low of two. Image Source: © Matts-Åke-Belin. Graphic created by FHWA."

Because road safety showed continuous improvement in Sweden through Vision Zero efforts, safety was no longer on the reform agenda. However, since 2010, the data showed that the downward trend in road safety was plateauing, so the Swedish government decided to draft a new policy document, renewing its commitment to Vision Zero. In 2016, Sweden announced its decision to relaunch Vision Zero as an intensified initiative. Based on this policy document, the government also commissioned the Swedish Transport Administration to lead the road safety effort. Sweden is back on track again: the number of fatalities per 100,000 inhabitants decreased from 6.7 road fatalities in the year 2000 to 1.8 fatalities in 2020, a 73-percent reduction.

“Vision Zero is important milestone in road safety because it emphasizes system safety and the need for many stakeholders to work together to deliver a safe system for all users,” says Swedish infrastructure minister Tomas Eneroth.

"A speed hump in an urban area in Sweden. Photo Source: © Lars Ekman."
This is an example of traffic calming feature in an urban area in Sweden.

The Safe System Approach in Australia

Australia has achieved success in reducing road deaths since a peak in the early 1970s. Road deaths decreased from around 3,800 per year (about 30 deaths per 100,000 population) in 1970 to around 2,000 deaths in the early 1990s (about 11 deaths per 100,000). However, despite these safety gains, the improvements plateaued throughout the 1990s. To renew efforts and achieve even greater road safety outcomes, Australia adopted the Safe System Approach as the guiding principle for road safety. This approach was based on the Swedish Vision Zero and Dutch Sustainable Safety strategies.

In 2003, Eric Howard, then the head of road safety for the Australian state of Victoria, was invited to Sweden to learn about the implementation of the Vision Zero approach. Upon his return, he says, “I presented to the Vicroads management team. The presentation was very warmly received and Vicroads decided to adopt Safe System thinking.” Other road agencies also became interested in this approach around this time.

The Australian road and transport ministers adopted the Safe System Approach in 2004 and embedded it at the federal level as part of the 2005/2006 National Road Safety Action Plan produced by the Australian Transport Council in 2005.

Early Implementation Period 

The early discussion by road agencies focused on ways to provide environments where the human tolerance to impact forces is not exceeded when road users make errors. Management of vehicle speeds and provision of forgiving roads and roadsides seemed to be the best way forward. However, early guidance on appropriate speed limits for different road environments based on Safe System principles and survivability were met with political opposition.

Several states experienced early successes to scale up investment in safe road infrastructure through the provision of forgiving roads and roadsides (such as roadside barrier protection systems). This period in the early to mid-2000s also saw the adoption of some new approaches to help meet Safe System objectives, including a focus on fatal as well as serious injury outcomes, the importance of road safety metrics, attempts to identify infrastructure requirements to achieve Safe System outcomes, and evolving assessment approaches that quantified fatal and serious injury risk.

"Photo of cable barrier used along a roadside in Gunnison County, Colorado, to prevent vehicles from going down into a ditch or from hitting fixed objects. Photo Source: FHWA."
Cable barrier used along a roadside in Gunnison County, Colorado.

However, 5 years after the formal adoption of the Safe System Approach in Australia, researchers noted a lack of tangible commitment to actions required for Safe System implementation. The country needed a revised approach to road infrastructure that embedded Safe System principles, funding for infrastructure, a requirement for motorists to drive at safer speeds, vehicle improvements, and the necessity for the community to accept a “no harm” road system.

A full decade after the adoption of the Safe System Approach, the vision for the Safe System strategy was clearer, but the steps required to reach these objectives were less understood. For example, there was no clear, practical guidance on embedding Safe System principles into the provision of new infrastructure or the upgrading of existing infrastructure. In the first years of Australia’s Safe System Approach, a lot of time was spent trying to define what was meant by a “Safe System,” and many debates occurred about the theoretical interpretation (for example, the role of road user responsibility).

Implementation of Safe System Approach Activity

More recently, around 2015, Australia entered a new era of Safe System Approach implementation. Although not consistent in all locations, realization grew about how to bring about substantive change—which builds on early successes but appears to have accelerated Safe System implementation for several reasons.

The critical importance of speed management is becoming more apparent to road managers and the public—that without effective management of speed and energy there will be no significant reduction in deaths and serious injury. A number of locations now have speed limits of 20 miles (approximately 30 kilometers) per hour to protect vulnerable roads users, while speed limits are increasingly being reduced on low-quality, high-risk rural roads, from the default 60 miles (approximately100 kilometers) per hour to 50 miles (approximately 80 kilometers) or even less. Political understanding is growing on the safety and wider community benefits of this approach, and also on the level of public acceptance of these lower speeds. However, the understanding and response on this issue are not universal, and more political support is needed from the policymakers.

As for road infrastructure, the emergence of tools to help assess Safe System impacts from projects as part of design has been beneficial, including the Safe System Assessment Framework (SSAF), and the Extended Kinetic Energy Management Model for Intersections framework (X-KEMM-X). SSAF provides information about whether road design options are aligned with Safe System outcomes, guidance on ways to improve the design, and impact of this improvement on death and serious injury. This tool is now compulsory for certain projects in several Australian states.

X-KEMM-X calculates the chance of death and serious injury at each conflict point at an intersection based on different design options. Changes in this risk can be determined based on changes in design. Both X-KEMM-X and SSAF provide clear information to designers on the safety implications from their decisions, and led to changes in policies, including the use of alternative intersection designs such as raised platforms.

Also, innovation provided new solutions to fill some of the gaps in Australia’s toolbox of road safety interventions. These new tools are providing better ways to manage speed and energy at critical locations, including through the use of raised pedestrian crossings, platforms at intersections, and vehicle-activated speed limit signs at high-speed intersections.

"A street with a raised platform prior to a roundabout in Australia. Photo Source: © Blair Turner."
This high-speed roundabout in Victoria, Australia, uses a raised platform to manage speed.

Australia has now set a national target with the objective of reaching zero deaths and serious injuries by 2050. This is significant because it paves the way for long-term, sustainable road safety improvements that are more likely to meet this ambitious target. Shorter-term (10-year) strategies work towards this ultimate Safe System objective, and the new draft road safety strategy currently sets a target of a 50-percent reduction in deaths per capita by 2030.

The new strategy emphasizes the use of outcome measures and safety performance targets. These items are also important because they allow close monitoring of new road safety interventions, the impacts they have on targeted behaviors, and the ultimate change in fatal and serious injury crashes that occurs from these interventions.

“You cannot underestimate the focus a transparent and measurable target brings to determining the allocation of resources and urgency in implementation,” says Gabby O’Neill, the head of the Office of Road Safety with the Australian Department of Infrastructure, Transport, Regional Development and Communications. “Within the new National Road Safety Strategy 2021–2030 we’re setting outcome measures to support a staged approach to achieving Vision Zero by 2050.”

The Future for Australia 

There are still issues to resolve to assist in the longer-term implementation of the Safe System Approach in Australia. The concerns include the need to increase awareness among the public and policymakers that there is still a significant road safety problem to address; that deaths and serious injuries are not a necessary by-product of transport, and are not acceptable; that there are effective interventions to reduce severe crashes; and that Australia can eventually eliminate fatalities and harm from their roads.

Oslo, Norway: Safe System Successes 

In 2019, the Norwegian capital of Oslo became an instant benchmark for road safety, when, after 50 years of steadily decreasing traffic fatalities, no vulnerable road users—defined for Norwegian statistics as pedestrians, cyclists, and motorcyclists—lost their lives in the city for an entire year.

While Oslo has experienced several traffic fatalities since 2019, particularly during the COVID-19 pandemic, it is still relevant to take a deeper look at the city’s efforts to advance urban road safety, considering the Safe System Approach methodology.

Norway implemented Vision Zero nationwide in 2002, 5 years after Sweden. In 2020, currently the latest year with official figures, Norway recorded the world’s safest roads in terms of road deaths per vehicle kilometers traveled for the fifth year in a row. National regulations on vehicle safety, speed limits, and highway design provide a foundation for Oslo’s efforts.

Vision Zero and the Safe System Approach aim to address the public health issue of death and serious injuries from road traffic. Even though fatalities and harm have been reduced on a national scale, the challenge remains for urban areas to address safety for vulnerable road users. In 2019, 85 percent of serious injuries in Oslo occurred in vulnerable road users.

The focus on road safety alone can lead to a false conflict between safety and increased walking and cycling. Limited road capacity combined with urban growth makes walking, cycling, and transit a necessity. Safer conditions for vulnerable road users should lead to more people walking and cycling and fewer people killed or injured. In 2013, while preparing a new ambitious cycling strategy, a city survey revealed that prospective cyclists cared most about feeling safe while cycling. To make more people get on their bikes, the city not only had to make its streets safer, but those streets had to feel safe, too. The survey, and the resulting cycling strategy enacted in 2015, can be seen as a watershed moment in how the city works on road safety.

Oslo has always received broad political support for road safety, particularly when it comes to implementing sidewalks and safe walking routes to schools. In addition, politicians provide a generous budget for street improvements, bike lanes, and public transit funded by the city’s many toll roads.

The idea that pedestrians and cyclists need to feel safe, on their own terms, should be considered as a natural extension of the Safe System Approach. This perspective is needed because work on road safety sometimes seems to exclude pedestrians’ and cyclists’ needs. Cities contain hostile environments where pedestrians and cyclists are inconvenienced in the name of their own safety—for instance, where a dangerous crosswalk has been removed in the name of safety, under the false assumption that users will accept a longer, safer detour. A lack of user perspectives in planning can cause unintended use and increased risk. A part of Oslo’s success resulted from meticulously weeding out these situations through countless reconstructions of crosswalks, sidewalks, and intersections.

To reach its goals, Oslo has embraced its activists. The city offers a strategy to build its bike network piece by piece, seeking to make cyclists and road safety activists hungry for more improvements. The city has responded to the demand for road safety measures by identifying opportunities for fast and cheap improvements. For example, in providing space for bike lanes by removing parking. The measure can be reversible, but experience demonstrates that opposition to removing parking spaces wanes when the new bike paths are put into place and being used. Simple and cheap measures improve safety on a short-term basis and can pave the way for bigger road reconstructions where necessary in future. Seeing every improvement as a taste for what is to come, rather than an end result, also gives the city flexibility to improve on projects when it sees how users and neighbors react to changes. This strategy helps lower tensions in projects where public discourse can reach heated levels.

"A picture of a two-lane street with a temporary bike lane with parking removed is placed above a more recent picture of the same street with permanent bike lanes on both sides of the street. Photo Source: © City of Oslo."
View of the street Åkebergveien in Oslo, Norway. Parking was removed to make room for a temporary bike lane going uphill before the street was rebuilt.

Traffic safety improvements are standard practice in every road project in Oslo. However, traffic changes over time in pace with urban development and therefore the city’s work with traffic calming is continuous. The city works to eliminate specific dangers, for example by regularly revising speed limits all over the city in recent years and implementing traffic-calming measures such as speed bumps or hourglass chicanes where necessary. In 2020, Oslo studied data on bicycle-related crashes in all the city’s intersections, looking for particular patterns of crashes that could indicate the most important measures to work with in future. Narrowing intersections is among the continuous traffic calming measures the city works with. Reducing crossing distances for pedestrians as much as possible and allowing maximum 26 feet crossing distance reduces their exposure to traffic. Traffic islands often let the pedestrian focus on traffic from one direction at a time and make the crosswalk recognizable at a distance for drivers.

"A cyclist on a cargo bike crosses a narrowed intersection of a roadway in Olso, Norway. Photo Source: © City of Oslo."
This narrowing of an intersection forces a speed reduction for motorized traffic that are about to turn. This improves a driver’s and cyclist’s ability to notice one another and interact in a safe manner. Narrowing intersections also reduce crossing distances for pedestrians and the amount of time they are exposed to motorized traffic.

One of the most important measures for cyclists is the separation between them and vehicular traffic. This is achieved by elevating bike lanes, by placing medians between the bike and motor lanes, and leading bike lanes out of conflict points, such as bus stops. Parking and loading docks are placed next to the motor lane with a median with a minimum of 2.6 feet safety distance to allow opening of car doors and to allow pedestrians to orient themselves before crossing the bike path. Conflicts between pedestrians and cyclists are addressed with crosswalks on the bike path and avoiding elements blocking the line of sight. Reducing the number of places where cyclists are led into mixed traffic on busy roads increase safety and reduce the level of stress on both parties.

To increase the advantage of cycling over driving, all new one-way streets in Oslo have to allow counterflow cycling. This allows cyclists a wider range of route options than motorists. The city has worked to implement this in hundreds of city blocks in existing one-way streets over the past decade. Motorized traffic volumes are typically low in one-way streets, reducing the number of interactions that may end in crashes.

"A city street with vehicular traffic flowing in one direction and a designated bicycle lane that flows in the opposite direction. Photo Source: © Geir Anders Rybakken Ørslien, City of Oslo."
Shown here is an example of a counterflow bike lane in a one-way street in Oslo. Motorized traffic volumes are typically low in one-way streets, reducing the number of interactions that may end in crashes.

However, one of the recent challenges to traffic safety work is the new policy around the General Data Protection Regulation. This legislation has resulted in anonymization of data on crashes to the point that most planners in Norway lack access to information on where different road users came from and where they are at the time of a crash. This poses the challenge of responding appropriately with road safety improvements following a crash and runs the risk of not adequately identifying or addressing the problem with road design. Planners respond to the best of their ability and to feedback from the public on places or situations where they feel unsafe. In the future, professionals hope to again gain access to more of the registered data that can help target road safety improvements based on crashes on the roads.

The most successful recipe in Oslo’s experience has been the broad general public support for traffic safety measures and the political support for reducing parking or number of lanes for motorized traffic to give space for sidewalks and bike lanes. The result shows a steady increase in cycling and the same low level of crashes. In 2019, Oslo reported zero pedestrian or cyclist fatalities and only one driver fatality, and the programs and measures the city have adopted relate to this success.

Building on Safe System Examples for the Future 

The United States can learn much from how international partners have implemented the Safe System Approach in their countries and cities. Early adopters in Australia, Sweden, and the city of Oslo have gained recent international recognition for their history and lessons learned implementing a Safe System Approach. Applying Safe System experiences from Australia, Sweden, and Oslo can help to scale up the U.S. approach to zero deaths and fewer injuries along the Nation’s roads.

"A roadway in Olso that includes designated lanes for cyclists. Cyclists are pictured in the designated lanes; to the left of the cyclist, and across a grass median, cars and a motorcyclist are on the roadway. Photo Source: © Geir Anders Rybakken Ørslien, City of Oslo."
Lessons learned from implementation of the Safe System Approach in countries and cities around the world—like Oslo, Norway, shown here—can help the United States with its own adoption of the principles.

Michael S. Griffith is Director, Office of Safety Technologies, with the Federal Highway Administration. He holds a master’s in transportation engineering from the University of Maryland, a master’s in statistics from State University of New York at Buffalo, and a bachelor’s in business management from Ithaca College in New York.

Matts-Åke Belin, Ph.D., is director of the Vision Zero Academy at the Swedish Transport Administration. He obtained a Ph.D. in public health policy from Karolinska Institute in Stockholm, Sweden and serves as an adjunct professor on traffic safety at the KTH Royal Institute of Technology.

Anders Hartmann is a senior advisor on walking, cycling, and road safety with a Norwegian planning and engineering consulting firm. He holds a master’s degree in architecture from the Oslo School of Architecture and Design.

Mari Svolsbru is the assistant head of the Department for Walking, Cycling, and Public Transit at the Agency for Urban Environment in the city of Oslo. She holds a master’s degree in human geography from the University of Oslo.

Blair Turner, Ph.D., is a senior transport specialist at the World Bank’s Global Road Safety Facility. Prior to this, he spent the last 15 years implementing Safe System as part of his role with the Australian Road Research Board. He obtained his Ph.D. in civil engineering from the University of Adelaide, Australia, and his master’s in psychology from the University of Canterbury, New Zealand.