Keywords

Introduction

While Safe Systems and Vision Zero are synonymous or near-synonymous in many areas of the world, the terms have evolved with slightly different meanings in the USA. A number of jurisdictions across the nation have adopted programs using Vision Zero terminology that incorporate some, but not all, of the principles commonly associated with Safe Systems. These jurisdictions typically focus on the ethical imperative of reaching zero traffic deaths, but recognition and adoption of other Safe System principles varies widely, including system design that accommodates human error and reduces the level of kinetic energy in crashes, and a shared responsibility for crashes by system owners. In communities where the full Safe System concept has yet to be institutionalized, Vision Zero is sometimes used as part of public campaigns that seek behavior changes such as reduced speeding and distracted driving.

The term, Safe Systems, is used primarily among safety professionals in the USA. While the term has yet to become part of the daily professional vernacular, when it is used, the implied definition is typically close to the commonly understood Safe Systems principles. This chapter will address the background, status, and trajectory of both Vision Zero and Safe Systems, using these US terminologies.

Early Consideration

In the late 1990s, as Scandinavian countries were securing Parliamentary endorsement for Safe Systems (Belin et al. 2012), the United States was experiencing a period of unprecedented success in behavioral road safety using a different approach, high-visibility law enforcement. The Click-It or Ticket seat belt program was launched in the State of North Carolina in 1993, adopting a technique that had shown promise in Canada and elsewhere, using an aggressive statewide implementation strategy (Tison and Williams 2010).

The effect of the Click It or Ticket high-visibility law enforcement technique was sufficiently positive that national attention was soon focused on this approach. Federal leadership, along with support from the automotive and insurance industries, further encouraged state and local adoption. In 2000, other states followed the North Carolina example, and in 2002, federal incentive funding was linked to state adoption of the Click It or Ticket program, and a coordinated nationwide campaign was launched to further encourage implementation (Runge 2002).

With federal, state and corporate safety leadership focusing on high-visibility law enforcement, relatively little attention was given in the USA to the road safety innovation occurring in Sweden, The Netherlands and later, Australia, the UK and other countries. As early as 1999, the Federal Highway Administration issued a technical report including a detailed description of the new Swedish Vision Zero program (Federal Highway Administration 1999), however this news did not stimulate widespread interest or action at the time. In 2000, the State of Washington became the first jurisdiction to adopt a zero traffic death policy, referring to their program as Target Zero (Washington Traffic Safety Commission 2019).

By 2007, several indicators of state and local implementation of the Click It or Ticket program began to show declines, including law enforcement activity as measured by seat belt tickets issued per population, investment in publicity about seat belt law enforcement, and public awareness of enforcement activity immediately following the coordinated national implementation campaign (Nichols et al. 2016). Various factors may have contributed to the decline in state and local high visibility enforcement activity. Earlier reports cited competing demands on enforcement agency budgets and personnel resources, along with increasingly complex criminal issues, as contributing to reductions in traffic law enforcement (Wiliszowski et al. 2001).

A reduced emphasis and investment in high-visibility traffic law enforcement may have stimulated interest in alternative safety approaches, including Vision Zero and Safe Systems. Among the first US cities to make public commitments consistent with Vision Zero principles was the City of Chicago. An Action Agenda published by the Chicago Department of Transportation in 2012 established a 10-year goal to eliminate traffic deaths (Chicago Department of Transportation 2012). The Action Agenda did not specifically cite Vison Zero or Safe Systems, but included several of the underlying principles, including a systemic approach to crash injury reduction and acknowledgement of human injury tolerance and its relationship to vehicle speed, in addition to the ethical imperative of a zero-fatality goal.

Focus on Zero

In 2014, a group of eight organizations representing government agencies at state and local levels released Toward Zero Deaths: A National Strategy on Highway Safety. The result of 5 years of development, including multiple levels of stakeholder engagement, the Toward Zero Deaths strategy was a substantial step forward in several respects.

Through a series of webinars and workshops, the development process brought together an extraordinary range of safety professionals, including representatives of agencies with responsibility for driver licensing, law enforcement, road construction and maintenance, commercial vehicle regulation, road user behavior, and emergency medical response. Reaching widespread agreement on the importance of a zero-based goal for traffic deaths among these professionals was a critical achievement with far-reaching implications.

A goal of zero traffic deaths can be viewed as contrary to conventional policy development methods that rely on cost-benefit analyses to allocate resources among social needs. A zero-death ethical imperative implies that there is no threshold of traffic deaths – other than zero – that would justify shifting resources away from road safety. This misalignment with conventional safety policy perspectives can be uncomfortable for safety professionals, as was found in Sweden during early years of Safe Systems implementation (Belin et al. 2012). The Toward Zero Deaths strategy made significant progress in overcoming such reservations among US safety professionals, achieving broad consensus on a zero-based road safety goal.

The Toward Zero Death strategy also heightened recognition of the need for a system wide approach to traffic safety. The strategy was developed and presented in a way that emphasizes the need for a comprehensive approach including behavioral, roadway, vehicle, safety management and data systems, and emergency response interventions (Toward Zero Deaths Steering Committee 2015). The strategy includes more than 180 recommended actions across these areas.

The Toward Zero Deaths strategy did not focus specifically on the Safe Systems approach. However, the broad endorsement of the zero-based goal, the inclusiveness of the development process, and the emphasis on a system wide strategy were progressive contributions to road safety thought in the U.S.

Initial Steps

Vision Zero Cities

High-profile, city-led activity towards the Safe Systems approach began in New York City (NYC) with the support of a well-organized, politically influential advocacy group, Transportation Alternatives (TA). TA developed a public report in 2011 showcasing the basic Safe Systems concepts, highlighting advances made in other nations, and laying out a blueprint for NYC adoption. The report initially gained the attention of safety advocates and later attracted a broader audience when TA effectively inserted the topic into the 2013 NYC mayoral election. Importantly, all of the leading candidates committed to TA’s Vision Zero challenge during their campaigns, and the candidate who won, Mayor Bill deBlasio, tasked his staff almost immediately with developing the city’s initial Vision Zero plan. The plan explicitly stated that “No level of fatality on City streets is inevitable or acceptable” (City of New York 2014), and it laid out specific actions to be pursued in roadway design, regulations, enforcement, data-tracking, local and state policy changes, and others.

This early and quick embrace of Vision Zero in NYC can be credited, in part, to the following: effective grassroots advocacy that planted the seeds in a hotly contested election; a “strong-mayor” system in NYC, in which leaders of departments, such as transportation, police, public health, etc., are directed by the city’s chief executive; and the nascent and powerful movement among local residents who lost loved ones to traffic injuries and organized for Vision Zero.

This organized voice for victims accelerated change. Now called Families for Safe Streets, the group was formed by those who had lost sons, daughters, husbands, and other loved ones, as well as some who had survived serious traffic crashes themselves. The influence of these individuals in the early days of NYC’s Vision Zero development was powerful because their personal and often heart-breaking stories helped move the issue of traffic safety from being viewed as a routine, technical issue to a deeply emotional and urgent rallying cry for change. NYC’s Families for Safe Streets group is supported by TA, giving it organizational and administrative backing. However, the group speaks with its own distinct voice, successfully advocating for long-desired policy and legislative changes. This victim advocacy enabled important progress. For instance, members of Families for Safe Streets are credited with helping to pass key legislation in the State of New York, allowing NYC to lower speed limits from 30 to 25 mph and to add automated speed cameras in school zones. Overall, in its first years of Vision Zero commitment, NYC experienced a 31% decline in traffic deaths, from 299 in 2013, the year prior to Vision Zero, to 205 in 2018. Nationwide traffic deaths increased by 12% during the same period. An increase of 16 deaths in NYC in 2019 was a setback, but still amounted to a 26% drop since 2013, just before Vision Zero was adopted (City of New York 2020).

The second US city to adopt Vision Zero was San Francisco , also in 2014. As in NYC, interest was initiated by local advocacy groups, specifically two membership organizations that promoted bicycling and walking. The impetus was an upsurge in traffic fatalities in the city, especially among people walking and biking. Particularly compelling was the highly publicized death of a 6-year-old child hit and killed on New Year’s Eve while walking with her mother in a crosswalk. That tragedy occurred on a street where advocates had long been fighting for safety improvements to little avail. Local advocates approached the Mayor, as well as leaders of the transportation, police, and public health departments, and urged adoption and implementation of Vision Zero. City officials agreed and activity built upon the city’s strong base of recent work focused on data-driven pedestrian safety planning, which was co-led by transportation and public health officials.

The Beginning of a National Movement

Following the strong focus on Click It or Ticket during the 2000–2005 era, federal leadership in behavioral safety moved on to other emerging traffic risks. Based on the extraordinary success of Click It or Ticket, similar high-visibility enforcement approaches were attempted as part of an emphasis on reducing driver distraction between 2010 and 2013 and for improving pedestrian safety in 2013–2015. However, implementation of the high-visibility enforcement approach was less consistent across the nation and results were not as remarkable for these other programs as in the earlier seat belt experience (National Highway Traffic Safety Administration 2014).

By 2016, a combination of factors motivated federal transportation leaders to work with stakeholders to define a longer-term path for road safety in the USA. Changes in public support for strong laws and aggressive law enforcement were diminishing prospects for repeating prior successes with these approaches. Meanwhile, after a decade of gradual declines in road deaths associated with the downturn of the national economy during the Great Recession, traffic fatalities started to rise again (He 2016). Additionally, public interest in the emergence of self-driving cars had reached a point where some safety advocates were concerned that commitment to behavioral safety programs may wane as a result of unrealistic expectations regarding the imminent arrival of fully automated passenger cars.

Federal officials at the US Department of Transportation gathered safety stakeholders in October 2016 to consider options for progress. At this meeting, behavioral health experts reviewed existing traffic safety program strategies and compared them to techniques used in other areas of health behavior change, such as anti-smoking campaigns. This expert review concluded that the current range of program strategies used for improving traffic behaviors – including those recommended in the Toward Zero Deaths National Strategy – compared favorably to those used in other areas of public health. There were few apparent opportunities for improving traffic safety programs by adopting strategies that had proven effective elsewhere. Additionally, experts on vehicle automation pointed out that while self-driving cars promise substantial safety benefit, those vehicles will not reach widespread use for a number of decades, confirming the ongoing importance of road safety behavioral programs for at least 20–30 years.

Also discussed at this conference was the concept of Safe Systems and the experience of Sweden in using this innovative approach to improve the effectiveness of both conventional and emerging safety strategies. At the conclusion of the conference, there was interest in articulating a long-term traffic safety vision for the USA that would describe how conventional evidence-based programs, as recommended in the Toward Zero Deaths National Strategy, might fit together with the future potential of automation and the Safe Systems approach.

Formulating a Long-Term Vision

In late 2016, a larger group of safety stakeholders was invited to help formulate this long-term traffic safety vision and facilitate its implementation. A Road to Zero Coalition was launched with leadership from the National Safety Council (a non-government organization) in collaboration with three safety agencies of the US Department of Transportation, the National Highway Traffic Safety Administration, the Federal Highway Administration and the Federal Motor Carrier Safety Administration. A Road to Zero Steering Group was formed with representatives from a range of stakeholder organizations. The Swedish Transport Administration was asked for advice and was an active participant in deliberations.

A decision was made by the Road to Zero leadership organizations to develop a 30-year vision for reducing traffic deaths to zero, or near zero, a timeframe that would be long enough to consider the role of emerging vehicle automation technology in achieving this objective, but still within the comprehension or experience of many safety professionals. Assistance in articulating the vision came from the RAND Corporation, a non-profit research institution. The planning methodology presented in Fig. 1 was designed specifically for this purpose, including elements of back casting, assumption-based planning and three-horizon foresight. The vision was formulated over a series of meetings over the first half of 2017. Continued input was solicited from the Steering Group and federal collaborators as drafts were prepared, reviewed and refined throughout the remainder of the year. Coalition meetings were conducted quarterly and membership increased from 150 public and private sector organizations, including cities, nonprofits, businesses, and government agencies at the first gathering, to approximately 900 3 years later.

Fig. 1
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Three horizons of change proposed by the Road to Zero vision. (Source: Adapted from Curry et al. 2008)

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The Road to Zero Vision

The completed Road to Zero Vision, released in April 2018, presents a forecast of traffic safety in the year 2050, depicted in a series of community scenarios, along with an explanation of how that future was achieved (Ecola et al. 2018). The 30-year vision predicted by the Road to Zero describes the potential result of investment in three areas or horizons of change: Double Down on What Works, Prioritize Safety, and Accelerate Technology.

The first of these, identified as Double-Down on What Works, reflects the potential impact of maximizing implementation of the wide range of evidence-based strategies that have been documented in the fields of roadway engineering, driver and road user behavioral safety, vehicle safety engineering, and emergency medical response and pre-hospital care. These policies and practices are the result of decades of research, development and refinement by engineers, psychologists, physicians, academics and other professionals. They include the most effective and feasible approaches developed to improve road safety, and many of the strategies have yet to be fully implemented and therefore hold unrealized potential. The Toward Zero Deaths National Strategy lists evidence-based interventions that were available in 2015 from across these fields, such as enacting safety belt laws, installing road shoulder and centerline rumble strips, and lowering speeds and creating dedicated bike space in cities. The number of such countermeasures continues to grow as new techniques are developed and evaluated.

The second horizon of change proposed by the Road to Zero vision is Prioritize Safety which includes adoption of Safe Systems principles and consequent realization of a Safety Culture. The idea of Traffic Safety Culture had been discussed previously in the Toward Zero Deaths Strategy, described as the set of social values, beliefs, and attitudes concerning safety, combined with perceptions of group norms and of the degree of individual control available to affect safety outcomes. The focus on Traffic Safety Culture in the widely-endorsed Toward Zero Death Strategy could be seen as a measure of its broad acceptance among US safety constituents at the time of its release in 2015.

The concept of Safe Systems did not receive comparable widespread US endorsement until the formulation of the Road to Zero vision was completed in 2018. In the Road to Zero vision, the Safe Systems approach is presented as a complement to the Toward Zero Deaths Strategy rather than as a new set of tools or interventions to improve road safety. In the context of the overall vision, Safe Systems is positioned as a means for extending the value of conventional practices by applying them in strategic and systemic ways. Future scenarios in the Road to Zero vision depict several applications of Safe Systems principles, including how cities systematically design roads to accommodate human error, for example by replacing signalized intersections with roundabouts that prevent deadly high-speed side-impact crashes that occur when a driver mistakenly runs through a signal. Others show how crash energy levels have been lowered to accommodate human injury tolerance by narrowing streets in certain locations, slowing traffic so that a collision with a vulnerable road user is unlikely to result in a death. Additional scenarios describe how automatic emergency braking prevents a crash resulting from a combination of driver and pedestrian error and how impairment detection technology prevents a drunk driver from operating their vehicle. All of these examples of Safe Systems principles use practices included among the recommendations of the Toward Zero Death National Strategy.

The third horizon of change described in the Road to Zero vision is Accelerating Advanced Technology. Our current road system places very high demand on driver vigilance to avoid crashes, and lapses in road user performance result in frequent crashes. Automation of vehicle control functions that have conventionally been the responsibility of the driver has tremendous potential for reducing these crashes and associated injuries. While a few of these automated functions, such as Electronic Stability Control, Automatic Emergency Braking and Lane Keeping Assist are already in some new vehicles, decades will pass before natural market forces bring such technology to the cars driven by the highest risk drivers, such as those who are most likely to drive after drinking alcohol. Yet more time will pass before the market will permeate the fleet with fully-automated vehicles. The Road to Zero vision stresses the need to supplement market forces with incentives, subsidies and regulations that could accelerate this technology deployment trend along with its safety benefits.

Expansion of Vision Zero Cities

Following the adoption of Vison Zero by New York City and San Francisco in 2014, additional cities developed and implemented similar programs. As of April 2020, there were 43 communities in the USA with public Vision Zero commitments, mostly at the city level and several at the regional or county levels, as indicated in Fig. 2 (Vision Zero Network 2020). While it is true that most of the early adopters of Vision Zero in the USA were large cities, such as Seattle, Washington; Boston, Massachusetts; and Washington, D.C., there is an increasing number of smaller- and mid-sized communities, as well as suburban communities, making Vision Zero commitments. Rural communities have expressed interest, but have yet to move in significant numbers to make public commitments to Vision Zero.

Fig. 2
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US Vision Zero cities in 2020. (Source: Vision Zero Network)

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Notably, the 43 US communities that have adopted Vision Zero planning and implementation efforts as of 2020 are independently and locally led. While their work is influenced by state and federal activities, their core work is largely separate from other governmental levels, except where specific changes are needed, such as seeking authority from the state to make changes in local speed limits.

Differences Between Local-Level Vision Zero & State-Level Toward Zero Deaths Efforts

In general, city-led Vision Zero efforts have developed differently than state-level zero-based approaches, such as Toward Zero Deaths programs. For instance, most of the 43 Vision Zero cities set a target year for reaching zero traffic deaths and severe injuries, generally in the range of 10–15 years into the future. They develop plans based on those targets with clear, actionable strategies that can be measured over time. This has not been a widespread practice at the state level, where broader “zero deaths” language is often used in their federally required state highway safety plans. While there are exceptions such as the State of Washington, State governments have not typically linked funding priorities or policy changes to zero goals, or proposed explicit, public-facing timelines for actions and results.

Another difference is that local Vision Zero efforts have been more likely to engage non-traditional safety partners, building a strong base for change. For instance, Vision Zero cities are increasingly engaging local public health departments in traffic safety work, along with school district leaders and community members, especially those representing groups most impacted by traffic injury and death, such as seniors and communities of color and low-income residents.

In addition, many Vision Zero cities are using a data-driven approach to elevate issues of equity within traffic safety planning and practices. Research shows that people of color and low-income communities are more likely to be negatively impacted by traffic conditions, as are children and seniors, as well as people walking and bicycling. Many local Vision Zero efforts are analyzing these data to inform efforts to address disparities in communities when it comes to safe mobility. This equity-driven approach has, so far, been less prominent at the state level.

Local-level Vision Zero efforts and state-level Toward Zero Deaths programs are generally similar in their lack of explicit link to the Safe Systems approach. Recognizing this disconnect and the potential benefits of more fully integrating in Safe Systems principles, some national organizations have focused on improving understanding of these principles among transportation professionals and facilitating their adoption through planning and implementation. These groups range from nonprofits, such as the Vision Zero Network, and professional organizations such as the Institute of Transportation Engineers (ITE), to governmental agencies, such as the Federal Highway Administration and the National Highway Traffic Safety Administration.

Promoting and Facilitating Further Safe Systems Adoption in the U.S.

Vision Zero Network

While Vision Zero cities (and regions) generally operate independently, a significant amount of information-sharing and peer-influence takes place among them. This is supported in part by the Vision Zero Network (VZN), a nonprofit started in 2015, with the goal of advancing Vision Zero in the US VZN connects these communities with a forum for sharing plans and experiences, and provides leadership and resources, including an emphasis on the Safe Systems approach as the basis of Vision Zero. VZN encourages partnerships between transportation officials and public health, law enforcement, and policymaking professionals, as well as community advocates. VZN conducts regular calls, meetings and webinars to share information, and produces resources to boost Vision Zero understanding, adoption, and implementation. Priorities of VZN include focusing on speed management strategies, elevating equity in Vision Zero and measuring the benefits of Vision Zero actions for broader adoption and effectiveness.

Vison Zero cities in the USA are evolving to fit local needs and conditions, and their level of commitment to the principles of Safe Systems varies. While the Vison Zero Network encourages this diversity of program design and focus, it also works with local program leaders to achieve greater convergence around Safe Systems principles and implementation.

Safe Systems Work Group

Following the introduction of the Road to Zero Vision, leadership from the roadway engineering profession took steps to build upon the endorsement of the Safe Systems concept. The ITE established a standing Safe Systems work group to advance acceptance and adoption in the USA. The initial objectives of the work group are to:

  1. 1.

    Develop a Safe Systems definition/principles

  2. 2.

    Identify core Safe Systems resources

  3. 3.

    Develop an introductory Safe Systems webinar

  4. 4.

    Develop a Safe Systems Action Plan

Members of the work group represent city, county, state and federal governments, academic institutions, and urban development and vulnerable road user advocates. Recognizing the extent of institutional change necessary for widespread US adoption, the work group deliberated on definitions and principles for Safe Systems that would be consistent with international thought and practice while being appropriate and feasible in the US context. Starting with the contemporary global definition as articulated by the World Resources Institute (Welle et al. 2018) and others, the work group adjusted emphasis and arrived at a practical definition that focused on two key principles:

  • A Safe System is designed to anticipate human error.

  • A Safe System is designed to accommodate human injury tolerance.

These two principles were viewed by the work group as a viable starting place that could stimulate change, show benefit, and establish a framework that might later be developed toward the more complete contemporary global definition (Institute of Transportation Engineers 2019). Further points of explanation were provided that touched on the comprehensive system approach and on the idea of shared responsibility:

  • A Safe System seeks safety through aggressive use of vehicle, roadway, and operational changes rather than relying solely on behavioral changes.

  • A Safe System does not absolve the user of responsibility for safe behavior, but neither does it absolve the system owner or operator of responsibility for safe design or maintenance.

The work group established a web resource for Safe Systems technical literature (Institute of Transportation Engineers 2019a) including fact sheets addressing the new framework along with a number of important Safe Systems references.

An educational webinar was developed and presented by the workgroup in November 2019, drawing nearly 300 participants. The learning objectives of the Introduction to Safe Systems Webinar were to:

  • Introduce Safe Systems as an approach in the U.S.

  • Recognize the foundation and elements of a Safe System

  • Describe how Safe Systems may apply to roadway owners and operators in the U.S.

  • Examine how vehicle design and technology are playing a role in Safe Systems

The webinar featured presentations by three widely-respected road safety opinion leaders, and focused on the role of vehicles and roadways in a Safe System. An introductory discussion reviewed the framework developed by the work group and addressed several anticipated questions from the US audience.

One of these questions concerned trade-offs that might be necessary to achieve a Safe System. Potential concessions in vehicle through-put were identified, with an example of reduced speeds in areas where vulnerable road users are present in order to reduce the probability of serious injury if a pedestrian or cyclist is struck by a car. Other potential concessions in road user freedom of choice were pointed out, such as reduced opportunity to drive under the influence of alcohol when impairment detection devices are implemented. Justifications for such concessions were offered, including the moral imperative to maximize safety and the need for a transportation system that accommodates all road users rather than prioritizing those in motor vehicles.

Another anticipated question concerned the pathway for achieving a Safe System. How could such a radical change be made in the US transportation system? The presenters offered an approach that would accomplish change through many small decisions. That is, if system owners and operators would consider the full range of options when making each decision about system design and function during their routine work, and choose the option that is best aligned with the Safe Systems framework, change would accumulate and system wide transformation could occur over time.

A third question was addressed concerning the relevance of conventional safety interventions in a Safe System. Presenters explained that many familiar interventions would be used in a Safe System. Some commonly used interventions, such as rumble strips and Electronic Stability Control systems, are completely consistent with Safe Systems principles because their function is to compensate for driver error. Others, such as lane markings and intersection treatments, may be used differently in a Safe System with the objective of separating vulnerable road users from vehicle traffic to reduce opportunities for error, or to slow traffic in high-risk areas to reduce the probability of serious injury if a collision occurs. Presenters stressed that system owners and operators need to be open-minded about new techniques in order to facilitate a successful transition to a Safe System.

The Safe Systems Work Group designed and administered a survey in September 2019 to gauge knowledge and attitudes about Safe Systems among safety professionals in the USA. The survey instrument was sent to about 500 Road to Zero Coalition members who, in a prior survey, had expressed interest in the section of the Road to Zero vision that addresses Safe Systems and Safety Culture. Responses were received from 88 individuals.

  • More than 80% of respondents report being somewhat or very familiar with Safe Systems. This proportion is likely to overestimate knowledge of Safe Systems among all US road safety professionals since the sample frame consisted of individuals who had expressed interest in the Safe Systems portion of the Road to Zero vision.

  • Of those working for a public agency, just 11% indicated that Safe Systems was widely practiced in their jurisdiction. Fourteen percent reported that their agency used Safe Systems on a targeted basis, and 35% indicated that their agency sometimes practiced Safe Systems.

  • About 85% report that the biggest obstacle to Safe Systems implementation is either knowledge, funding, or leadership. Lack of knowledge was the most frequently reported obstacle at 34%, despite the fact that lack of training was reported by just 10%.

One interpretation of these findings is that the lack of interest by public agency leadership, as reported by respondents, may be discouraging technical professionals from taking advantage of available training resources and preventing further investment of public funds in Safe Systems solutions.

To provide further clarity and direction for Safe Systems development, the Safe Systems Working Group developed a concept diagram and is formulating an action plan. The concept diagram presented in Fig. 3 illustrates the central role of Safe System principles, depicts the use of familiar elements of safety programs, Safe Roads, Safe Speeds, Safe Road Users, Safe Vehicles and Post-Crash Care, as means for implementing these principles, and shows how these activities define and reflect the ambient Safety Culture.

Fig. 3
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Safe System concept diagram. ( Source: Institute of Transportation Engineers)

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The pending action plan being developed by the Safe System Working Group will provide additional detail on activities that can be pursued in a 5-year time frame to increase awareness and build support for Safe Systems, develop and disseminate resources and tools for implementation, and institutionalize Safe Systems principles in the practices of road safety professionals.

Safe Systems Academic Center

Concurrent with the development of the Road to Zero Vision, the US Department of Transportation established a University Transportation Center at the University of North Carolina with the purpose of advancing transportation safety through a multi-disciplinary systems-based approach. Working with four other universities, the Collaborative Sciences Center for Road Safety (CSCRS) is conducting research and developing guidance that combines the principles of Safe Systems with the discipline of systems science.

The CSCRS was established in 2016 with a 6-year project period. The Collaboration has generated a range of research and educational products, including an important report on implementing Safe Systems in the USA (Dumbaugh et al. 2019), and an analysis of Vision Zero plans developed by cities across the USA (Collaborative Sciences Center for Road Safety 2020a). The CSCRS convened a Safe Systems Summit in April 2019 that was attended by more than 340 safety professionals from 29 states (Collaborative Sciences Center for Road Safety 2020b) .

Federal Leadership and Support

The US Constitution preserves broad authority for state governments, including the design and construction of roads and regulation of road users. Vehicle regulation is among the powers given to the federal government since variations among state requirements for vehicle design or performance would be inefficient for vehicle production and hamper both interstate and international commerce. Decentralization of road authority has many advantages with regard to meeting local needs across states that vary significantly in terrain, climate and population. However, this lack of central road authority also has implications for achieving widespread change of the scale necessary for nationwide adoption of the Safe Systems approach.

A federal-aid highway program provides funding each year to states for construction, maintenance and improvement of certain roads and for safety programs targeting road design and road user behavior. Under this program, funds are available for specific purposes and with prescribed eligibility and spending constraints designed to encourage state investment in evidence-based methods.

For 2019, the federal-aid highway program provided more than $40 billion to states (Congressional Research Service 2019). Although these funds do not make up the largest share of road construction and maintenance costs, the program is nonetheless influential in establishing and reinforcing roadway design, maintenance and safety priorities. Investment areas, methods or specific interventions that are emphasized in the federal-aid program are seen as federal priorities or endorsements reflecting the will of the nation’s highest-level transportation policymakers, thus influencing state activities.

The federal-aid highway program is revised or renewed on a 6-year cycle as part of the Congressional authorization of the functions and powers of the US Department of Transportation. As the end of a cycle approaches, Congressional offices formulate plans for the upcoming authorization period, and organizations with interests in roadway funding often make recommendations to these offices regarding emphasis areas consistent with their particular needs.

Authorization of the federal-aid highway program is a key opportunity to endorse the Safe Systems approach in the USA. As of 2020, this federal program has yet to address the concept of Safe Systems or provide an incentive for state or local roadway agencies to invest in this direction. Beyond explicit endorsement of the approach, Congressional authorization of the federal-aid highway could also facilitate Safe Systems implementation by incentivizing speed management activities at the state and local levels and removing the specific prohibition against spending program resources on automated traffic enforcement systems. This prohibition discourages adoption of automated speed enforcement, a strategy that has been an important element of Safe Systems implementation in other countries.

Focus on Children

With support from the FIA Foundation and others, the National Center for Safe Routes to School at the Highway Safety Research Center at the University of North Carolina is promoting adoption of Vision Zero for Youth programs both in the USA and internationally (National Center for Safe Routes to School 2020). These programs are designed first for the benefit of child and youth safety, with a focus on pedestrian and bicycle safety near schools, and have a secondary benefit of introducing Vision Zero and Safe Systems principles to communities. Child-focused safety activities are often easier to start than other road safety programs and frequently develop into larger community-wide efforts (National Center for Safe Routes to School 2013). Vision Zero for Youth programs often begin with a walking assessment following routes that children use to walk or bicycle to school. School officials, city officials and parents are engaged in identifying safety problems and applying Safe Systems principles to reduce risk.

New Approach: New Expectations

There are challenges to developing and implementing the Safe Systems approach in the U.S., particularly involving community expectations and political leadership, as well as openness to change. Because Safe Systems implementation tends to involve changes to the design of roadways, policies and vehicles, significant change can be slower than with behavioral interventions such as law enforcement programs. While the benefits of a Safe Systems approach are likely greater and more sustainable in terms of lives saved, compared to compliance-based programs, its implementation is slower and results are cumulative rather than sudden.

Political leadership is key to effective implementation of Safe Systems, both by committing the public funds necessary for improvements to roads and by gaining public support for policy and design changes, such as lower speed limits. Support from political leaders can also help gain acceptance for unfamiliar road features such traffic calming, roundabouts, and design changes, such as road diets, which reduce motor vehicle travel lanes to better accommodate space for walking, biking, and transit.

However, political leadership also brings certain challenges. For instance, the Vision Zero, or Safe Systems, approach is not a quick-fix but rather a long-term investment in change. This means that it is likely that a political champion may not see benefits during her or his leadership tenure and could even see negative trends in road safety resulting from a host of other factors (possibly out of their control), making it a riskier political calculation. Also, a close public association between a Vision Zero program and a specific political leader who champions the cause may lessen the subsequent leader’s desire to visibly associate with it, as they may want to show their own priorities or brand.

US experience with Safe Systems implementation differs from that of Sweden and other nations in that the movement has been led largely from the local and advocacy levels, as well as by national professional organizations, and less so by the national government. This grassroots approach is perhaps less efficient than strong national leadership in securing resources and direction for local implementation. But considering political realities and the size of the nation and its federal structure, the US strategy of relying on the support of many local leaders may provide more stability in the long term.

Achieving widespread implementation of Safe System techniques in the USA will require a concentrated effort to raise awareness of the potential value of these practices at both the political and practitioner level across the many jurisdictions with responsibility for planning, operating and maintaining the US roadway system. Identifying pathways to implementation for urban, suburban and rural areas will be necessary to illustrate how the Safe System concepts can be adopted in a variety of settings. Tools, case studies and evaluations will help Safe System practices be deployed and support the concept of accomplishing change through many small decisions. The Road to Zero Coalition and its members, with support from the USDOT, can play an important continuing role in supporting the advancement of Safe Systems and movement toward the ultimate goal of Vision Zero.