PUBLIC ROADS

www.fhwa.dot.gov Winter 2022
Winter 2022 | Vol. 85, No. 4

The Safe System Approach 

PAGE 3 FEATURES

3 Making our Roads Safer through a Safe System Approach 

by Mark Doctor and Chimai Ngo

“FHWA has a vision of working towards zero deaths on our Nation’s 

roads, along with many of our partners and stakeholders. To make this 

vision a reality, we are revitalizing our safety program with the adoption 

of the Safe System Approach.” 

– Cheryl Walker, Associate Administrator for Safety, FHWA.

8 The Highway Safety Improvement Program: 

Paving the Road to a Safer Future

by Danielle Betkey and Karen Scurry

FHWA identifies opportunities to integrate the Safe System Approach 

with States’ existing and future highway safety improvement programs.

13 The Safe System Paradigm: Reducing Fatalities 

and Injuries at the Nation’s Intersections

by Jeffrey B. Shaw, Richard J. (R.J.) Porter, Michael R. Dunn, 

Jonathan Soika, and Ivy B. Huang

A recently completed Federal Highway Administration project 

proposes a quantitative method to evaluate intersection 

designs according to Safe System principles.

18 NHTSA’s Safe System Approach: 

Educating and Protecting All Road Users

by Robert Ritter, Dee Williams, and Gamunu Wijetunge

NHTSA supports the Safe System Approach 

through data-driven measures to make the Nation’s 

transportation network more secure for everyone.

24 Speed Management Is Key to Road Safety

by Guan Xu, Abdul Zineddin, Randolph Atkins, and Sarah Abel

Advancing speed management for safety can reduce speeding-related 

injuries and fatalities on the Nation’s highways and byways.

30 The Safe System Approach: 

How States and Cities Are Saving Lives

by Chimai Ngo, John Milton, Lily Reynolds, Rachel Carpenter, and Clay Veka

The Safe System Approach offers useful tactics for saving 

lives and preventing fatalities on our Nation’s roadways.

36 Applying a Safe System Approach Across the Globe

by Matts-Åke Belin, Anders Hartmann, Mari Svolsbru, 

Blair Turner, and Michael S. Griffith

Studying three examples in Sweden, Australia, and 

Norway can help other countries, including the United 

States, pave their way to zero deaths on highways.

PAGE 36 

© Geir Anders Rybakken Ørslien, City of Oslo.

DEPARTMENTS

Guest Editorial ..................................................1

Hot Topic ..........................................................2

Along the Road ..............................................43

Internet Watch ..............................................46

Training Update .............................................47

COVERS and ABOVE—Nations around the world are adopting 

the Safe System Approach, with the goal of eliminating deaths 

and serious injuries on roadways. Here in the United States, 

the Safe System Approach is beginning to be implemented to 

improve safety for all Americans. The Approach looks at five 

elements of a safe transportation system: Safe Roads, Safe 

Speeds, Safe Vehicles, Safe Road Users, and Post-Crash Care.

Photo illustration by FHWA. Safe Road Users image: 

© ambrozinio / Shutterstock.com. Wheelchair image: 

© Vergani Fotografia / AdobeStock.com. Safe Vehicles 

image: Source: NHTSA. Safe Speeds image: © Ole_CNX 

/ AdobeStock.com. Safe Roads image: Source: NHTSA. 

Post-Crash Care image: Gorodenkoff / AdobeStock.com. 

Crosswalk background © Win Nondakowit / AdobeStock.com. 

Pedestrians: © xiaosan / AdobeStock.com.
WWW.FHWA.DOT.GOV | 1

U.S. Department of Transportation 

Federal Highway Administration

U.S. Department of Transportation

Pete Buttigieg, Secretary

Federal Highway Administration

Stephanie Pollack, Acting Administrator

Office of Research, Development, and Technology

Kelly Regal, Associate Administrator 

Shana Baker, Director, Office of Corporate Research, 

Technology, and Innovation Management

TaMara McCrae, Editor-in-Chief

Lisa A. Shuler, Distribution Manager

Editorial Board: 

T. Everett, T. Hess, H. Kalla, M. Knopp, A. Lucero, 

I. Rico, G. Shepherd, C. Walker 

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A. Zozicharow

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Public Roads, Winter 2022 (Washington, DC: 2021) 

https://doi.org/10.21949/1521704

NOTICE

This document is disseminated under the sponsorship of the 

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GUEST EDITORIAL

A Promising Future

I

n 2020, the number of people killed on 

our Nation’s roadways was the highest since 

2007, and early estimates of fatalities for the 

first half of 2021 reflect the largest six-month 

increase in fatalities ever. Similarly, over the 

past decade, the proportion—and number—

of fatalities occurring outside a vehicle 

dramatically increased. Given these increases, 

countless families and friends have suffered 

the unimaginable loss of loved ones to trafficrelated crashes. These troubling trends have 

prompted transportation professionals to begin 

reexamining their approach to safety.

This unacceptable loss of life highlights the limitations of our traditional 

transportation strategies and emphasizes that our approach to roadway safety 

must change. At the Federal Highway Administration, we are pivoting to the Safe 

System Approach—an internationally recognized and successful practice that sets 

an ethical imperative that no one should die or be seriously injured on roadways. 

The Safe System Approach centers on humans, regardless of their mode of travel, 

and requires proactively building redundant layers of protection. The human body 

is vulnerable; as such, there is only so much kinetic energy transfer it can withstand. 

Under the Safe System Approach, the transportation network is designed and oper

ated in a way that minimizes serious injuries and fatalities in crashes.

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Particularly troubling is the dramatic increase in the number of pedestrians killed 

by motor vehicles. These fatalities have increased over the last decade by approxi

mately 50 percent. Moreover, research shows that people walking in lower-income 

areas are more likely to be struck and killed than people walking in higher-income 

neighborhoods. Similarly, studies have demonstrated that persons with disabilities, 

racial minorities, gender minorities, children, older adults, and other underserved 

communities are at a higher risk of dying or being injured in a crash. They also have 

less access to affordable, quality, and accessible transportation choices. Because of 

these increased risks, the topics of both equity and pedestrian safety are intertwined 

in many of the articles within this issue.

The Safe System Approach also stresses that safety is everyone’s responsibility 

(even if the word “safety” isn’t in our job title). The Safe System Approach offers a 

promising future; imagine a world where no one dies from vehicle crashes. Tested 

and proven strategies in engineering countermeasures hold much promise to save 

lives and prevent serious injuries. Notably, results from Australia, Sweden, and 

Norway—early adopters of Safe System approaches—show that fatalities on our 

roadways can be prevented. You can read more about the Safe System Approach in 

“Making our Roads Safer through a Safe System Approach” (on page 3).

This special issue of Public Roads also elaborates on FHWA’s efforts to integrate 

the Safe System Approach into our portfolio to comprehensively address safe roads 

and safe speeds (see “The Highway Safety Improvement Program: Paving the 

Road to a Safer Future” on page 8). Our partners at the National Highway Traffic 

Safety Administration—with whom we work closely to advance the Safe System 

Approach—detail their work in addressing safe vehicles, road users, and post-crash 

care (on page 18). We highlight Safe System examples from States and cities as 

well as international partners (on pages 30 and 36, respectively). Finally, the issue 

provides insight into “Speed Management Is Key to Road Safety” (on page 24) and 

the Hot Topic focuses on “Bringing Human Factors Research Into the Next Era” 

(on page 2).

By embracing the Safe System Approach, we are embracing a safer and brighter 

future on our roadways.

Cheryl J. Walker

Associate Administrator for Safety

Federal Highway Administration

Source: FHWA.
2 | PUBLIC ROADS | WINTER 2022

Current model of the Highway Driving Simulator.

Source: FHWA.

HOT TOPIC

Bringing Human 

Factors Research Into 

the Next Era

by JESSE EISERT and MICHELLE ARNOLD

The Human Factors team is in the process of expanding its research 

capabilities and tools in an effort to ensure 

that the Federal Highway Administration 

(FHWA) remains on the cutting edge of 

research. This expansion will be achieved 

via four unique mechanisms: the Highway 

Driving Simulator (HDS) Virtual System 

Upgrade, the Virtual Reality (VR) Lab 

Upgrade, the HDS and CARMASM

Integration, and the development of 

Connected Simulation.

The mission of the Human Factors team is to further the 

understanding of highway user needs so that those needs can be 

incorporated into roadway design, construction, repair, and 

improvement. Because the American highway system is constantly 

evolving, it is imperative that the team’s research tools evolve so 

that the team can accurately study this system.

HDS Virtual System Upgrade

Currently, the Human Factors teams’ HDS is running on sevenyear-old software and hardware—a lifetime in technology years. 

One of the most important upgrades being made to the HDS is 

the installation of 4k projectors. These new projectors and visual 

system upgrades will help keep the HDS at the front of cuttingedge research by improving its overall immersion, scenario realism, 

and its accuracy surrounding real-world simulations. These new 

upgrades will also meet the requirements of modern and 

developing automated system technologies.

HDS and CARMA Integration

Another upgrade in development is the integration of the HDS 

into the CARMA platform. By merging the HDS with the 

capabilities of the CARMA platform, the Human Factors team 

anticipates new, game-changing potentialities. This incorporation 

will provide opportunities for the Human Factors team’s HDS 

studies to utilize real-world automated vehicle models, to combine 

on-road and simulation-based testing of various scenarios, and to 

study the requirements for new automated systems.

For more information about CARMA, please visit https://www

.fhwa.dot.gov/publications/publicroads/19autumn/hottopic.cfm.

VR Laboratory Upgrade

The first considerable modification in renovating the Human 

Factors teams’ VR Lab is its relocation to a larger area that allows 

for more space for virtual simulation—physical space is integral to 

creating authentic, immersive experiences. The Human Factors 

team is also switching to a next generation VR headset that will 

allow for eye tracking, increased resolution and frame rate, and 

mixed reality. And the Human Factors team is working on 

upgrading some of the lab’s peripherals into an omni-directional 

treadmill and a VR bike to allow for even more flexibility in 

scenario and research testing.

HDS and VR Lab Connected Simulations

Lastly, the Human Factors team is working toward developing a 

distributed simulation in which the HDS and VR Lab will be 

integrated into a shared simulation. Although in its early stages, 

this intriguing technology will allow for the testing of highly 

complex scenarios with real participants in a safe setting.

As FHWA moves into the next decade, the Human Factors 

team is hard at work to ensure it continues to lead the charge when 

it comes to understanding how users of our roadways interact with 

one another. These new research tools and capabilities will help 

further the Human Factors teams’ knowledge and understanding.

JESSE EISERT leads various human factors research at FHWA including auto

mation and how it interacts with vulnerable road users. He received his Ph.D. 

in psychology from George Mason University.

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MICHELLE ARNOLD leads a variety of human factors research and manages 

the FHWA highway driving simulator laboratory contract. She received her 

Ph.D. in psychology from Western Michigan University.

For more information, see https://highways.dot.gov/research

/laboratories/human-factors-laboratory/human-factors-team-members

or contact Jesse Eisert, 202-493-3284, Jesse.Eisert@dot.gov or 

Michelle Arnold, 202-493-3990, Michelle.Arnold@dot.gov.

Aerial view of the VR world from within the VR Lab.

Source: FHWA.
WWW.FHWA.DOT.GOV | 3

The United States is beginning to adopt a Safe System 

Approach to address roadway safety challenges.

Source: FHWA.

MAKING OUR ROADS SAFER 

through a Safe System Approach 

“FHWA has a vision of working towards zero deaths on our Nation’s roads, along 

with many of our partners and stakeholders. To make this vision a reality, we are 

revitalizing our safety program with the adoption of the Safe System Approach.” 

– Cheryl Walker, Associate Administrator for Safety, FHWA.

by MARK DOCTOR and CHIMAI NGO

Achieving the vision of eliminating deaths and serious injuries from the 

Nation’s roads may seem daunting with 

traffic fatalities in the United States stub

bornly remaining between 32,000 and 

39,000 annually for more than a decade. 

To make meaningful progress, changes are 

needed in how to think about the traffic 

safety problem and the approaches to solve 

the problem. The Safe System Approach 

is being applied with great success in a 

growing number of nations and cities 

around the world and has now taken hold 

in the United States.

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The Safe System Approach has origins 

in Sweden through its Vision Zero program 

and with the Sustainable Safety program 

in the Netherlands. These early adopters 

experienced impressive decreases in road 

traffic fatalities—each with at least a 

50-percent reduction in fatalities between 

1994 and 2015. The concept has spread 

to other countries in Europe and beyond 

with notable success in Australia and 

New Zealand.

The Safe System Approach 

requires a culture that 

places safety first and 

foremost in road system 

investment decisions.

In comparison, fatalities in the United 

States decreased by less than 13 percent 

during the same 1994–2015 period. 

International success with the Safe System 

Approach gives promise that the United 

States may also be able to achieve similar 

positive safety outcomes. With growing 

momentum and initiatives being taken by 

agencies across the country, the United 

States has started on the journey toward 

implementing a Safe System. 

The vision of eliminating fatalities and 

serious injuries on the Nation’s roads are 

shared through such parallel initiatives as 

Vision Zero, Toward Zero Deaths, and 

Road to Zero. All three efforts acknowledge 

the importance of implementing the Safe 

System Approach in different contexts. 

With Vision Zero, local communities are 

applying the Safe System Approach with 

a focus on safe mobility for all road users, 

especially those in the underserved commu

nities. The Vision Zero Network is working 

with communities committed to reaching 

their Vision Zero goals. Many State agencies 

have adopted zero-deaths goals in their Stra

tegic Highway Safety Plans (SHSP), using 

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the Safe System framework from the report 

Toward Zero Deaths: A National Strategy 

on Highway Safety. The American Associa

tion of State Highway and Transportation 

Officials (AASHTO) has been leading 

Toward Zero Deaths efforts since 2009. A 

third effort, the Road to Zero Coalition, 

under the leadership of the National Safety 

Council, also identified as a main initiative 

the need to prioritize safety by adopting 

a Safe System Approach and to create a 

positive safety culture.

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Six Foundational Principles for Understanding and Applying the Safe System Approach:

• Deaths and serious injuries are unacceptable—While no crashes are 

desirable, the Safe System Approach emphasizes a focus on crashes 

that result in death and serious injuries. Regardless of road users’ 

socio-economic backgrounds, their abilities, and the modes 

they use, no one should experience deaths or serious injuries 

when using the transportation system.

• Humans make mistakes—Road users will inevitably 

make mistakes, and those mistakes can lead to 

crashes. The Safe System Approach expects the 

road system be planned, designed, and operated 

to be forgiving of inevitable human mistakes, so 

that serious injury outcomes are unlikely to occur.

• Humans are vulnerable—Humans have limited 

ability to tolerate crash impacts before harm 

occurs. Although the exchange of kinetic energy 

in collisions among vehicles, objects, and road 

users has multiple determinants, applying the Safe 

System Approach involves managing the kinetic 

energy of crashes to avoid serious injury outcomes.

• Responsibility is shared—All stakeholders 

(transportation system users and managers, vehicle 

manufacturers, etc.) must work collaboratively 

to ensure that crashes don’t lead to fatal or 

serious injuries.

• Safety is proactive—Transportation agencies should use 

proactive and data-driven tools to identify and mitigate 

latent risks in the system, rather than waiting for crashes to occur 

and reacting afterwards.

• Redundancy is crucial—Reducing the risk of severe crash outcomes 

requires all parts of the system to be strengthened, so that if one element fails, the others still protect road users.

The Safe System Approach 

principles and elements.

Source: FHWA.

Safe System Approach 

Principles and Elements

The Safe System Approach starts with a 

mindset that it is unacceptable to allow 

deaths and serious injuries to occur on 

the roads. It also acknowledges that road 

users are human beings and that humans 

will inevitably make mistakes. On the 

roads, those mistakes may lead to crashes. 

The goal of “zero” is to eliminate fatal and 

serious injuries, not to eliminate crashes. 

This is a very important distinction for 

understanding how the road safety problem 

is viewed under the Safe System Approach. 

To achieve zero deaths and serious inju

ries, when crashes do happen, they must 

be managed so that the kinetic energy 

exchange on the human body is kept below 

the tolerable limits for serious harm to 

occur. This important principle is at the 

core of applying a Safe System Approach in 

designing and operating the road system. 

Human error is to be expected so the road 

infrastructure and vehicle technology must 

be designed and operated so that deaths 

and serious injuries are engineered out. This 

may be achieved first by reducing the risk 

of error occurring and secondly by keeping 

collision forces on the human body within 

tolerable levels, when crashes do occur, by 

managing speed and crash angles to reduce 

injury severity.

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The Safe System Approach considers five 

elements of a safe transportation system—

safe road users, safe vehicles, safe speeds, 

safe roads, and post-crash care—in an 

integrated and holistic manner. Achieving 

zero traffic deaths and serious injuries 

requires strengthening all five elements. A 

Safe System cannot be achieved without all 

five elements working in synergy. Within a 

Safe System Approach, weaknesses in one 

element may be compensated for with solu

tions in other areas. A true systems approach 

involves optimizing across all the elements 

to create layers of protection against harm 

on the roads.

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• Safe Road Users—The safety of 

all road users is equitably addressed, 

including those who walk, bike, drive, 

ride transit, or travel by other modes.

• Safe Vehicles—Vehicles are designed 

and regulated to minimize the 

frequency and severity of collisions 

using safety measures that incorporate 

the latest technology.

• Safe Speeds—Humans are less 

likely to survive high-speed crashes. 

Reducing speeds can accommodate 

human-injury tolerances in three ways: 

reducing impact forces, providing 

additional time for drivers to stop, and 

improving visibility.

• Safe Roads—Designing 

transportation infrastructure to 

accommodate human mistakes and 

injury tolerances can greatly reduce 

the severity of crashes that do occur. 
WWW.FHWA.DOT.GOV | 5

Examples include physically separating 

people traveling at different speeds, 

providing dedicated times for different 

users to move through a space, and 

alerting users to hazards and other 

road users.

• Post-Crash Care—People who are 

injured in collisions rely on emergency 

first responders to quickly locate and 

stabilize their injuries and transport 

them to medical facilities. Post-crash 

care also includes forensic analysis 

at the crash site, traffic incident 

management, and other activities.

© deberarr / AdobeStock.com.

Implementing a Safe System Approach requires 

finding equitable solutions for many road users.

Providing a Safe System for All

Progressing with implementation of a Safe 

System requires equitable solutions. By 

examining road safety data with correlations 

to community sociodemographic charac

teristics, many agencies have found that 

higher risks of crash deaths are concentrated 

in lower-income neighborhoods where 

exposure to traffic may be higher and past 

investments in safety programs and infra

structure may be lower. Prioritizing these 

communities for implementation of the 

Safe System Approach can offer substan

tial safety improvements and close the gap 

between risk in well-invested and under

served neighborhoods.

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“Centering equity within Vision Zero 

efforts is vitally important and timely,” 

says Leah Shahum, founder and execu

tive director of the Vision Zero Network. 

“Communities across the country are 

struggling with social, racial, and economic 

inequities, including disparities within the 

transportation realm. Low-income commu

nities and communities of color often bear 

a disproportionate burden of traffic-related 

injuries and fatalities. We cannot reach 

zero traffic deaths without addressing issues 

of equity.”

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Notable Safe System 

Practices: California, 

Florida, and Washington

Numerous transportation agencies across 

the United States have already begun to 

implement and institutionalize Safe System 

principles. While these agencies are at 

different stages of implementation, they all 

have pivoted to this approach with the goal 

of making positive and significant differ

ences in safety. Three such States are high

lighted here. Other articles in this issue of 

Public Roads will further detail these efforts.

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To integrate the Safe System Approach 

at the program level, the California 

Department of Transportation (Caltrans) 

introduced a new safety paradigm in 2020. 

The agency established the new Division 

of Safety Programs and incorporated four 

safety-focused initiatives or pillars into its 

SHSP. One of the pillars calls for implemen

tation of a Safe System Approach. The insti

tutional commitment to the Safe System 

Approach has been the foundation for many 

positive cultural and programmatic changes 

within the agency, one of which is the estab

lishment of the Pedestrian Systemic Safety 

Improvement Program that had been started 

as a pilot in 2016. The program integrates 

Safe System elements and principles into 

a systemic approach to further the goal of 

zero deaths.

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“Caltrans has adopted the Safe System 

Approach and is institutionalizing it depart

ment-wide as part of our new approach 

to safety,” says Rachel Carpenter, the chief 

safety officer for Caltrans. “Our updated 

Strategic Management Plan reflects our 

commitment to the Safe System Approach 

and we are actively working to incorporate 

Safe System principles and elements across 

all divisions and the entire project lifecycle.”

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6 | PUBLIC ROADS | WINTER 2022

Implementing a Safe Systems Approach is one of the four pillars of Caltran’s Strategic Highway Safety Plan.

© 2021 Caltrans

The Florida Department of Transporta

tion (FDOT) and its safety partners work 

toward their Vision Zero goal of zero fatal

ities and serious injuries through the State 

SHSP, which serves as the overall framework 

of efforts and activities to improve safety 

toward that ultimate goal. Florida’s 2021–

2025 SHSP introduced the Safe System 

Approach to address safety in an integrated 

manner with a collective commitment of 

time, talent, and resources to new priori

ties, strategies, and enhanced partnerships. 

Because Florida experienced a 27-percent 

increase in fatalities at intersections between 

2015 and 2019, intersections are identi

fied as an emphasis area within the SHSP. 

Among the focused strategies identified in 

the SHSP is the systematic use of Inter

section Control Evaluations to implement 

innovative designs such as roundabouts and 

reduced left-turn conflict intersections on 

projects that offer opportunities to make 

intersection improvements.

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Alan El-Urfali, the State traffic services 

program engineer for FDOT, says, 

“Including the Safe System for intersections 

assessment framework into our Intersection 

Control Evaluation process can help inform 

designers on better intersection design 

choices that proactively take steps to reduce 

fatal and serious crashes at intersections.”

The Washington State Department of 

Transportation (WSDOT) recognized that 

to achieve its zero-deaths goal, appropriate 

policies must be in place to implement a 

Safe System Approach throughout the plan

ning, programming, design, and operations 

sections of its department. WSDOT lever

ages its SHSP and Target Zero efforts to 

align Safe System principles across discipline 

areas and provide direction throughout 

capital and operational program elements. 

WSDOT changed the safety subprogram 

to emphasize proactive safety projects; 70 

percent of its funds are targeted towards the 

crash prevention category.

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“Adopting a Safe System Approach led 

WSDOT to change its philosophy to focus 

on fatal and serious rather than all crashes,” 

says John Milton, the State safety engineer 

at WSDOT. “Our focus also shifted to 

managing kinetic energy and addressing safe 

speeds through data-driven and perfor

mance-based approaches that incorporate 

using context-sensitive design.”

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This philosophical shift has resulted 

in many positive changes, among which 

are updated safety policies and associated 

budget programing, the creation of the 

Active Transportation division to recog

nize all transportation modes, updated 

design and traffic manuals to incorporate 

context-sensitive design and operations, 

a draft policy framework for injury mini

mization through speed management that 

serves as a model for any jurisdiction in the 

State, incorporation of safety for all modes 

in the new Transportation Systems Manage

ment and Operations plan currently under 

development, and incorporation of Level of 

Traffic Stress metrics for active transporta

tion in its definition of asset conditions to 

be used in programming preservation funds.

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One Death is Too 

Many: Portland, OR

The city of Portland, OR, committed to 

Vision Zero when the city council unan

imously passed a resolution in June 2015 

and adopted a Vision Zero Action Plan in 

December 2016. Portland’s reputation as 

a walkable, bikeable, and livable city was 

strong motivation to address a rise in the 

percentage of pedestrian deaths and steady 

percentage of bicycle deaths. Data indi

cated that while pedestrian trips account 

for about 9 percent of all trips in Portland, 

pedestrians were nearly one-third of the 

traffic-related deaths.

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Portland’s Vision Zero Action Plan also 

recognizes the need for working toward 

equitable communities and prioritizing 

infrastructure investments on the most 

dangerous streets in traditionally underin

vested communities. Using a data-driven 

approach, Portland was able to identify that 

although deadly or serious injury crashes 

can happen anywhere, more of them happen 

on certain street types. Wide, fast arterials 

with multiple lanes in each direction had a 

disproportionate number of traffic deaths. 

Also, many of the streets went through 

lower-income neighborhoods where people 

rely heavily on walking and transit. In 

Portland, more than half of deadly crashes 

occurred on just 8 percent of city streets. 

Improving this identified “high-crash 

network” is a central element of Portland’s 

Vision Zero strategy.

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Portland, OR, is known as a walkable and bikeable 

city, so its Vision Zero Action Plan includes a 

focus on safety and equity for all road users.

© Portland Bureau of Transportation.

A fundamental principle of the Safe 

System Approach is that people make 

mistakes. Impairment, speeding, distracted 

driving, aggressive driving—these are all 

discouraged behaviors and the Portland 

Vision Zero Action Plan includes coor

dinated actions to deter them. But the 

plan also acknowledges the role that street 

design plays to encourage and enable safe 

behaviors. Streets should discourage unsafe 

driving by design. Safer street designs can 
WWW.FHWA.DOT.GOV | 7

slow down traffic, provide visual cues that 

make it clear when different user groups 

share the space, and when needed, provide 

separation between the user groups when 

vehicular operating speeds are incompatible 

for sharing space with other users. Adhering 

to these design principles keep all people 

safer—even when they make mistakes.

With Portland’s data indicating a dispro

portionate number of pedestrian deaths, 

slowing vehicular speeds is a critical part 

of the city’s Vision Zero plan. A person’s 

chances for surviving a crash increase 

dramatically with lower speeds. A pedes

trian struck by a person driving at 40 miles 

(64 kilometers) per hour is 8 times more 

likely to die than one struck at 20 miles 

(32 kilometers) per hour. Managing speed 

is critical, and Portland has taken action by 

setting appropriate speed limits, designing 

streets to support safe speeds, and oper

ating safety camera programs to enforce 

speed limits.

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The Portland Vision Zero Action Plan 

recognizes that improving safety requires a 

suite of actions spanning policy, infrastruc

ture, education, and enforcement. This 

aligns closely with the Safe System prin

ciples of shared responsibility and having 

redundancy in the system.

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What’s Ahead of Us?

Creating a Safe System is a journey that will 

take time, commitment, and collaboration 

across disciplines. The Federal Highway 

Administration and its stakeholders 

across the transportation community are 

acting now to advance the Safe System 

Approach, making decisions guided by 

the underlying principles, and promoting 

implementation across the Nation. FHWA 

is making strides to advance the Safe 

System Approach through publications 

and outreach materials, including an 

overview flyer and awareness presentation. 

FHWA has issued several reports, including 

Integrating the Safe System Approach with 

the Highway Safety Improvement Program

(FHWA-SA-20-018) and Safe System-based 

Framework and Analytical Methodology 

for Assessing Intersections (FHWA-SA-21-

008). FHWA has also published a primer 

on the Safe System Approach for pedes

trians and bicyclists. These reports can be 

found on FHWA’s Zero Deaths website at 

-

https://safety.fhwa.dot.gov/zerodeaths, which 

provides resources on the Safe System 

Approach as well as material related to 

zero-deaths goals and strategies. Addition

ally, organizations and initiatives, including 

the Road to Zero Coalition, Toward Zero 

Deaths, and Vision Zero Network, offer 

valuable resources and references. The 

Institute of Transportation Engineers also 

offers a comprehensive website of technical 

resources for agencies looking to bring a 

Safe System Approach to their community.

-

As the United States advances along 

the journey to implement a Safe System 

to eliminate traffic deaths and serious 

injuries, everyone is a stakeholder with an 

important role.

MARK DOCTOR is a senior safety and design 

engineer in the FHWA Resource Center. Mark 

provides technical services and advances 

technology deployment in performance-based 

safety and design areas. He holds an M.S. degree 

in transportation engineering from the University 

of Florida.

CHIMAI NGO is a program manager for zero deaths, 

safety culture, and transportation safety planning 

initiatives in the FHWA Office of Safety. She holds 

a master’s degree in planning from the University 

of Virginia.

For more information, visit https://safety 

.fhwa.dot.gov/zerodeaths/, or contact Chimai 

Ngo at chimai.ngo@dot.gov or Mark Doctor 

at mark.doctor@dot.gov.

Many of the strategies identified in Portland’s Vision Zero Action Plan align 

along the elements of the Safe System Approach:

Safe Users • Traffic Safety Education programming

• Safe Ride Home Partnership Program

• Guidelines for later start times of parking enforcement to 

encourage impaired drivers to leave their car overnight 

(without having to worry about getting ticketed or towed)

Safe Speeds • Safety cameras

• Multimedia education campaign focusing 

on the human impact of speed

Safe Roads • Use street safety design elements on the high-crash network, 

which accounts for more than half of Portland’s deadly crashes

• Redesign streets to include landscaped medians, limited left turns, 

buffered bike lanes, enhanced bus transit, and additional crosswalks
8 | PUBLIC ROADS | WINTER 2022

THE HIGHWAY 

SAFETY 

IMPROVEMENT 

PROGRAM:

Paving the Road to a 

Safer Future

FHWA identifies opportunities 

to integrate the Safe System 

Approach with States’ existing 

and future highway safety 

improvement programs.

This section of highway has multiple roadway departure 

countermeasures, including rumble strips, guardrails, high 

friction surface treatment, and horizontal curve signs.

Source: FHWA.

by DANIELLE BETKEY and KAREN SCURRY

The Highway Safety Improvement Program (HSIP), which sets the funding and policy tone for national safety implementation 

efforts, is a key place to begin advancing implementation of the Safe 

System Approach. The HSIP includes the States’ Strategic Highway 

Safety Plan (SHSP) and the program of highway safety improve

ment projects (or States’ HSIPs), as well as foundational elements of 

the HSIP that influence both program areas. In the informational 

report Integrating the Safe System Approach with the Highway Safety 

Improvement Program (FHWA-SA-20-018), the Federal Highway 

Administration identified opportunities and noteworthy practices to 

align the Safe System principles with the foundational elements of 

the HSIP, SHSPs, and States’ HSIPs.

-

Overview of the HSIP

The FHWA oversees the HSIP, which is a core Federal-aid highway 

program, with the purpose to significantly reduce fatalities and 

serious injuries on all public roads through the implementation 

of highway safety improvement projects. The HSIP is a federally 

funded, State-administered program that requires each State to 

develop and administer a program that best meets its safety needs. 

The HSIP requires a data-driven, strategic, and performance-based 

approach to improving highway safety on all public roads.

As part of the HSIP, States are required to develop an SHSP that 

provides a comprehensive framework for reducing traffic fatalities 

and serious injuries on all public roads. The SHSP guides invest

ment decisions made in the HSIP toward projects that focus on 

mitigating the highest priority safety issues in each State. The SHSP 

is an opportunity for highway safety programs and partners in the 

State to work together to align goals, leverage resources, and collec

tively address the State’s safety challenges.

-

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According to FHWA’s Highway Safety Improvement Program 

Manual (FHWA-SA-09-029), “The SHSP influences decisions 

made during each step of the State HSIP process.” Thus, emphasis 

areas and strategies identified in the SHSP inform the development 

and selection of viable safety projects in the State’s HSIP process 

and guide a State’s investment decisionmaking. These safety projects 

include infrastructure countermeasures that further a State’s specific 

goal of reducing fatalities and serious injuries. The results of imple

menting and evaluating the HSIP in turn inform future SHSP and 

HSIP planning efforts. 

-

The SHSP data analysis, goals and emphasis areas feed into HSIP problem identification; 

the SHSP strategies feed into HSIP countermeasure identification; SHSP priorities and 

action plans support HSIP project prioritization; implementation of HSIP projects supports 

SHSP implementation; and HSIP evaluation feeds into the evaluation and update of the 

State’s SHSP.

Source: FHWA.
WWW.FHWA.DOT.GOV | 9

Integrating the Safe 

System within SHSPs

One of the first opportunities to incorpo

rate the Safe System Approach is within the 

State SHSP. The SHSP provides a unique 

opportunity to integrate the Safe System 

principles and core elements within the 

current SHSP framework. It also provides 

an opportunity to reframe the SHSP by 

refocusing countermeasures and strategies to 

align with the Safe System Approach. There 

are several opportunities that a State can 

take to begin integrating the Safe System 

Approach, including committing to a goal 

of zero fatalities, reorganizing the SHSP 

emphasis areas and strategies, and refocusing 

the speeding emphasis area.

-

Commit to a Zero Goal

The first step a State can take in updating 

the SHSP is to adopt a goal of zero fatal

ities. This supports the Safe System prin

ciple that deaths and serious injuries are 

unacceptable. Adopting a zero-death goal 

ensures that the SHSP’s top priority and 

focus is on achieving a reduction to zero. 

Many States have already begun commit

ting to zero-death goals in the SHSP. For 

example, the Washington State 2019 Strategic 

Highway Safety Plan has a Target Zero goal 

that represents the vision of zero deaths and 

serious injuries on Washington roadways 

by 2030. Maryland is another State that 

has made a commitment to zero deaths. 

According to the 2021–2025 Maryland 

State Strategic Highway Plan, the State’s 

zero death strategy “incorporates princi

ples from Vision Zero and other proven 

safety programs to provide a broad systems 

perspective that considers the interaction 

of the road user with the road design as a 

necessary component to achieve zero deaths 

on our roads.”

-

-

-

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“In Maryland, we consider even one 

roadway death to be unacceptable,” says 

Christine Nizer, Administrator at the 

Maryland Department of Transportation 

Motor Vehicle Administration. “By focusing 

on proven strategies to reduce fatalities 

and serious injuries, our SHSP reinforces 

what works and provides all our safety 

partners with a comprehensive framework 

including behavioral and engineering strat

egies to reduce and eliminate deaths and 

serious injuries.”

-

Reorganize SHSP Emphasis 

Areas and Strategies

Another way the Safe System Approach can 

be integrated into the SHSP is by organizing 

the SHSP around the Safe System’s six core 

principles and five elements. For example, a 

State may choose to fully replace emphasis 

areas with the five elements, and each of 

the elements would then incorporate all of 

the Safe System principles. Or States could 

revise emphasis areas within the framework 

of the five elements to become the overar

ching framework for the SHSP emphasis 

area strategies.

-

Before transitioning to a Safe System 

Approach in the SHSP, States would benefit 

from performing a Safe System assessment 

to determine how well the current SHSP’s 

emphasis area structure aligns with the 

Safe System elements and principles. By 

performing this assessment, States will have 

a better roadmap for pivoting to the Safe 

System Approach and creating a focus on 

the core principles and elements within the 

SHSP. States will also want to engage safety 

partners and stakeholders early to collab

orate and encourage engagement while 

also shifting to more effective and measur

able actions.

-

-

Several States have already begun 

developing SHSPs that reflect a Safe System 

Approach. Missouri’s 2021–2025 SHSP, 

Show-Me Zero: Driving Missouri Toward 

Safer Roads, aims to address four key 

behaviors (occupant protection, distracted 

driving, speed and aggressive driving, and 

impaired driving) and three roadway user 

groups (teen drivers, older drivers, and 

pedestrian and other nonmotorized users). 

Missouri selected these emphasis areas and 

user groups to represent “virtually every road 

user” and to ensure “no group or demo

graphic is unrepresented.” Missouri believes 

that this shift will help address the primary 

underlying causes of most fatal traffic 

crashes within the State and help move in a 

direction to achieve its zero goal.

-

Another State that has embraced the Safe 

System Approach is New Jersey, with the 

update of its 2020 SHSP. The New Jersey 

SHSP added a fifth “E” to the “4 E’s” of 

highway safety (engineering, enforcement, 

education, and emergency medical services) 

to place a new focus on equity for all of its 

safety investments.

“For the first time, New Jersey Depart

ment of Transportation (NJDOT) is 

recognizing equity as a priority in highway 

safety as part of our Strategic Highway 

Safety Plan,” says NJDOT Commissioner 

Diane Gutierrez-Scaccetti. “NJDOT is 

working diligently to ensure that all strate

gies and activities emanating from the plan 

fairly consider the needs of all users and all 

communities—particularly minority popu

lations, economically depressed communi

ties, and those that are differently abled.” 

-

-

-

-

New Jersey’s 2020 SHSP emphasis areas include equity to ensure highway safety investments are inclusive of the 

interests of traditionally underserved populations and is considered more deliberately.

© New Jersey Department of Transportation.

Refocus the Speeding 

Emphasis Area

The Safe System element for safe speeds 

represents another opportunity that 

can be directly addressed in the SHSP. 

Refocusing the speeding emphasis area on 

speed management and roadway design 

shifts the traditional application of educa

tion and enforcement strategies to using 

roadway design to reduce speeding-related 

crashes. It also addresses the Safe System 

principles that humans are vulnerable, 

responsibility is shared, and redundancy 

is crucial. Addressing designing for safe 

speeds and speed management in the SHSP 

can help States make progress toward the 

zero-fatality goal.

-

States can take a similar approach to 

what Minnesota and the city of Sacramento, 

CA, have done to address speeding. Minne

sota addresses speeding as an emphasis 

area in its 2020–2024 SHSP. In addition 

to developing strategies that only focus on 

education and enforcement, Minnesota has 

also included a strategy to improve road 

design and speed limit signing by seeking 

to use appropriate speed limits to account 

-
10 | PUBLIC ROADS | WINTER 2022

for roadway design, traffic, land use, and 

context. Sacramento has also identified 

roadway design in its 2018 Vision Zero 

Sacramento Action Plan as a primary tool to 

align enforcement efforts with reducing fatal 

crashes that occur at high speeds—whether 

the cause of the crash was speeding or not. 

The plan makes a clear connection between 

crash severity and speed, even in cases 

where the posted speed limit is deemed to 

be reasonable.

Integrating the Safe 

System within the HSIP

A roadway safety management process, 

which is the foundation of the State HSIP, 

forms a strong basis from which to integrate 

the Safe System Approach. This includes 

processes for problem identification, 

countermeasure identification, project prior

itization, and evaluation.

-

Problem Identification

Safety programs and identified improve

ment projects are based on a robust, datadriven process that considers both historic 

crash patterns and a proactive assessment of 

the crash causation factors that can lead to 

future crashes. Changing network screening 

methods to primarily focus on fatal and 

serious injury crash reduction opportunities 

can help refocus problem identification on 

the Safe System principle that deaths and 

serious injuries are unacceptable.

-

Many agencies also screen their transpor

tation network using a systemic approach 

to safety. The systemic approach to safety 

aligns with the Safe System principle that 

safety is proactive, by identifying loca

tions for potential safety improvement 

based on the presence of risk factors that 

are correlated with specific severe crash 

types. Most States implement systemic 

safety improvement projects through the 

HSIP. As described in Virginia’s Highway 

Safety Improvement Program 2020 Annual 

Report, the State “identified $136.7 million 

in potential funding through [fiscal year] 

2025 in order to implement eight systemic 

countermeasure initiatives” on roadways 

maintained by the Virginia Department of 

Transportation. “The systemic countermea

sure implementation projects in this initial 

Systemic Improvement Plan [are] estimated 

to save 61 lives and 1,174 injuries per year 

statewide once implemented.”

-

-

-

Some agencies are also beginning to 

consider equity in the problem identifi

cation process. Agencies can incorporate 

socioeconomic data as a potential risk factor 

in systemic safety analysis. The Minnesota 

Department of Transportation (MnDOT) 

created the Suitability of Pedestrian and 

Cyclist Environment (SPACE) tool, an 

index of 19 publicly available data measures 

from the U.S. Census and State agencies 

that includes measures of demographic 

populations, environmental justice factors, 

latent demand, and trip generator factors. 

Layering the SPACE score with crash data 

revealed that communities with a SPACE 

score greater than 50 represent 71 percent 

of crashes at 15 percent of road miles in 

the State. This demonstrates that an equity 

index, like the SPACE score, can be used 

as an effective predictive risk factor tool 

for crashes that result in fatalities and 

serious injuries.

-

“The SPACE score has helped us 

prioritize nonmotorized scoping efforts 

and understand the latent demand in the 

community,” says Sonja Piper, a pedestrian 

and bicycle safety engineer at MnDOT. 

“Additionally, the systemic risk attributed to 

the score has helped us rate HSIP projects. 

We’re looking at ways that SPACE can 

help prioritize our overall program delivery 

and have used the concepts of leveraging 

public data to generate similar analysis for 

other processes.“

The SPACE Score identifies latent demand for nonmotorized infrastructure by combining public data on 

(1) statewide pedestrian plan priority populations, (2) under-served communities, (3) current commuting 

patterns, and (4) trip generators. Of the 19 factors, only 1 is based on the existing infrastructure: a proactive 

risk assessment of MnDOT intersections to identify high risk locations for nonmotorist fatal and serious injury 

crashes. Note that the SPACE Score primarily identifies social geography and does not necessarily change with 

an engineering solution: it is one of multiple layers used to identify appropriate solutions.

© 2021 Minnesota Department of Transportation.

Similar to the proactive risk assessments in MnDOT safety plans, MnDOT analyzed whether there was 

over-representation of fatal and serious injury crashes based on the SPACE score. This graphic depicts the 

distributions of centerline miles on all public roads compared to nonmotorist crashes. Scores of 51 and above, 

where the site exceeds the thresholds for 10 or more of the SPACE factors, show over-representation. This 

is striking as the definition for SPACE was derived based on latent demand and priority populations and not 

necessarily a safety analysis.

© 2021 Minnesota Department of Transportation.
WWW.FHWA.DOT.GOV | 11

The hierarchy of controls illustrates the different 

approaches to user safety. The strategies that focus 

on elimination are at the top: these approaches are 

more effective in reducing fatalities and serious injuries 

because they eliminate exposure to the crash before it 

can occur. Substitution follows, where the focus is on 

strategies that lower the severity of injuries in the event 

of a crash. Next is engineering controls, where changes 

are made to the design and operation of the road system, 

vehicles, and programs. Administrative controls change 

the way people use the system through education, 

legislation, and policies. The final and least effective 

approach is personal protective equipment such as 

motorcycle helmets and protective gear.

© 2019 Washington State Department of Transportation.

Countermeasure Identification

As part of countermeasure identification, 

agencies identify proven effective safety 

countermeasures that address the specific 

crash patterns and factors present. Changing 

countermeasure identification to primarily 

focus on fatal and serious injury crash 

reduction opportunities can help refocus 

this evaluation on the Safe System principle 

that deaths and serious injuries are unac

ceptable. The Washington State Department 

of Transportation’s SHSP describes a hier

archy of controls to support countermeasure 

identification. The Washington State Strategic 

Highway Safety Plan 2019 states, “Priori

tizing efforts in this way creates a system 

that is generally more effective and protec

tive. While the most effective approaches 

may in some cases be more difficult or 

costly to implement initially within existing 

systems, total lifecycle benefits and avoided 

tragedies should be greater.”

-

-

-

-

Agencies can consider additional 

opportunities to incorporate human factor 

research (such as applying psychological 

and physiological principles to engineering 

and design) into the countermeasure 

identification process. Safety improvement 

projects should identify opportunities 

to minimize the potential for road users 

to make mistakes (such as intersection 

designs that reduce conflict points) as well 

as incorporate shared responsibility and 

design redundancy in the system to prevent 

crashes. This principle is currently inte

grated into some road infrastructure safety 

strategies, such as roadway departure, where 

the first priority to avoid a roadway depar

ture crash is to keep vehicles on the road 

(rumble strips, etc.). In the event a vehicle 

has left the travel lane, the second priority 

is to provide an opportunity for the vehicle 

to safely recover and reenter the travel 

way (clear zone). And last, the goal is to 

minimize the severity if roadway departure 

crashes do occur (such as using guardrails).

-

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Each State HSIP should address Safe 

System elements and principles in a coordi

nated and systemic manner, and not in silos. 

This can be accomplished by broadening 

the focus of engineering countermeasures to 

include roadway design or control elements 

that specifically support each Safe System 

element. This approach provides a buffer or 

redundancy in the system that can reduce 

the level of severity when a crash does occur. 

The countermeasure identification process is 

also a way to meaningfully engage popu

lations that are traditionally underserved 

in shared decisionmaking for projects. 

Improving the safety for all road users is 

an important consideration for all highway 

safety improvement projects.

-

-

Project Prioritization

Agencies use a variety of methods to 

prioritize safety projects, including bene

fit-cost analysis, ranking, and optimization 

approaches. Changing project prioritization 

methods to primarily focus on opportunities 

to reduce fatal and serious injury crashes 

aligns with the HSIP purpose and the vision 

of zero serious and fatal crashes. Including 

only the most serious injury crashes may 

result in a project prioritization different 

than when all crashes are factored in the 

calculation. The FHWA Selecting Projects 

and Strategies to Maximize Highway Safety 

Improvement Program Performance guide 

(FHWA-SA-20-001) explored this concept 

further with two pilot case studies using 

data from Ohio and Utah. In these case 

studies, using the benefit-cost ratio only 

for fatalities and serious injuries resulted in 

selecting projects expected to prevent more 

fatal and serious-injury crashes than the 

current project selection methods used by 

the two States.

-

In addition to benefit-cost ratio, States 

often consider other factors in the project 

prioritization process. These factors might 

include project readiness, geographical 

distribution, or public inputs. Agencies can 

also consider equity in project prioritization 

through the HSIP.

The Ohio Department of Transporta

tion (ODOT) made changes to its formal 

safety application process in the summer 

of 2021 for the fall round of applications. 

These changes included modifying the 

scoring criteria to give higher priority to 

projects that address crash severity and 

projects in communities with higher levels 

of poverty based on census data. Specifically, 

communities that reach certain thresholds 

for poverty/economic distress can receive 

up to 10 points toward their safety appli

cation and may be eligible for a reduced 

local match.

-

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These changes are necessary, notes 

Michelle May, ODOT’s highway safety 

program manager. “Traffic deaths in Ohio 

have risen six of the past seven years,” she 

says. “Focusing on severity will help ODOT 

better address these crashes. In Ohio, fatal 

and serious injury crashes are overrepre

sented by 10 percent within census block 

groups that have a poverty rate at or above 

10 percent, when adjusted for population. 

ODOT wants to help Ohio communities 

with fewer financial resources struggling to 

make critical safety investments.”

-

Evaluation

Evaluation is a key component of the HSIP 

and of the roadway safety management 

process in general. Evaluation enables 

agencies to determine the effectiveness of 

individual projects, countermeasures, and 

programs, and monitor and track progress 

toward annual safety performance targets 

and long-term safety goals. While many 
12 | PUBLIC ROADS | WINTER 2022

agencies have adopted a goal of zero deaths 

by 2050, States also set annual safety 

performance targets that serve as interim 

performance measures to monitor and track 

progress toward long-term goals. These 

interim performance measures enable agen

cies to take a step back, measure progress, 

and make course corrections if needed.

-

Agencies should also consider adopting 

key performance indicators specific to 

roadway infrastructure safety. A key perfor

mance indicator for road infrastructure 

should show the safety quality of a road 

network independent of road user behavior 

or vehicle technology. Ideally, agencies 

would estimate the level of safety of existing 

roads and establish indicators to improve 

the level of safety over time. However, this 

may be complicated to estimate, and data 

may not be readily available. In the interim, 

agencies may establish other relevant key 

performance indicators such as the provi

sion of additional infrastructure by length 

(for example, miles of rumble strips) or 

installation of additional infrastructure as a 

percentage of the road network (such as a 

percentage of areas with pedestrians where 

sidewalks are provided).

-

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Valuable insights gained in the evaluation 

process are fed back into the road safety 

decisionmaking process to enable proactive 

roadway safety changes. Through continued 

process and program improvement, agencies 

will achieve their safety performance goals.

This photo shows a guardrail segment with reflectors, which demonstrates redundancy. The reflectors will help keep 

vehicles on the road, but if needed the guardrail will prevent vehicles from leaving the road.

© Mikhail Priakhin / Shutterstock.com.

What’s Next?

Over the past couple of years, FHWA 

has been educating safety partners about 

the Safe System Approach. While there is 

general support and buy-in from major 

safety partners, practitioners are also 

seeking clarity about what the Safe System 

Approach looks like in practice and how to 

best integrate this approach into business 

practices and daily activities.

Establish Safe System Work Group and 

Conduct Pilot Projects. FHWA encour

ages agencies to establish a Safe System 

work group including representatives from 

various departments (planning, design, civil 

rights, enforcement, operations, mainte

nance) to determine the best path forward. 

FHWA will also be facilitating Safe System 

pilot projects in which a review team will 

conduct a road safety assessment of an 

existing or proposed project through a Safe 

System lens.

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Prioritize Equity. To adequately address 

equity in transportation safety, agencies 

should consider incorporating nontradi

tional data sources in their data-driven 

safety analysis. There are many free, publicly 

available, and easily accessible data sources 

to use to conduct equity analysis and target 

investment to address disparities in crash 

fatalities and serious injuries. These data 

include: (1) public health models in State 

and local agencies; (2) the Environmental 

Protection Agency’s Environmental Justice 

Screening and Mapping Tool, available at 

-

https://ejscreen.epa.gov/mapper; and (3) U.S. 

Census data. Agencies can then layer these 

models with crash data, infrastructure data, 

or transportation safety funding data to 

determine which communities are experi

encing disparities and target HSIP funding 

in those locations. Engaging with State 

and local stakeholders such as departments 

of health will help to better understand 

what data are available to support safety 

data analysis.

-

Conduct Additional Research. Additional 

research is necessary to fully integrate Safe 

System principles and elements into existing 

safety programs and projects. This research 

includes developing predictive models that 

focus on fatalities and serious injuries, rather 

than all crashes. Understanding kinetic 

energy transfer (crash magnitude) related to 

different modes, crash types, and roadway 

conditions could help States identify and 

prioritize projects. Research should also 

identify how kinetic energy models can 

help States identify and prioritize projects, 

including how the models can be used to 

complement or supplement crash predic

tion models.

-

Moving forward, agencies may also 

leverage backcasting, which identifies the 

infrastructure and funding that will be 

required to achieve zero traffic deaths in a 

future horizon year, and then set interim 

funding, policy, and program milestones 

between the current year and horizon year. 

This approach will enable States to show 

the level of investments necessary to reach 

long-term goals.

Transportation safety professionals play 

a key role in helping everyone get home 

safely—every trip, every time. By integrating 

Safe System principles and elements into 

existing safety programs and projects, safety 

professionals can lead by example, devel

oping model practices that can be integrated 

at all levels of roadway planning and engi

neering and across all disciplines that have a 

hand in supporting roadway safety.

-

-

DANIELLE BETKEY is a program manager with the 

FHWA Office of Safety. She holds a B.A. degree in 

business management from Towson University 

and an M.A. in business administration in technol

ogy management from the University of Phoenix.

-

KAREN SCURRY is a program manager with the 

FHWA Office of Safety. She holds both a B.S. and 

an M.S. in civil engineering from Rutgers University 

and is a registered professional engineer in the 

State of New Jersey.

The authors would like to thank Anthony 

Boutros, a Truman-Albright Fellow in the 

FHWA Office of Safety, for his contribu

tions to this article.

-

For more information, visit https://safety

.fhwa.dot.gov/hsip, or contact Danielle 

Betkey (202-366-9417; danielle.betkey

@dot.gov) or Karen Scurry (202-897-7168; 

karen.scurry@dot.gov).
WWW.FHWA.DOT.GOV | 13

THE SAFE SYSTEM PARADIGM:

Reducing Fatalities and Injuries at the Nation’s Intersections

A recently completed Federal Highway Administration project proposes a quantitative method to 

evaluate intersection designs according to Safe System principles.

Crashes at intersections contribute significantly to 

traffic fatalities and serious injuries in the United States. 

Applying the Safe System Approach to intersections can 

improve roadway safety at these critical junctions.

Source: FHWA.

by JEFFREY B. SHAW, RICHARD J. (R.J.) PORTER, MICHAEL R. DUNN, JONATHAN SOIKA, and IVY B. HUANG

The Safe System Approach represents a paradigm shift in how road safety is 

addressed in the United States and aligns 

with the growing number of Vision Zero 

goals, efforts, and action plans across the 

country. While Vision Zero describes 

the goal and Safe System describes the 

approach, both accept the premise that 

crashes will not be completely avoided. 

However, the Safe System Approach posits 

that no person should be killed or seri

ously injured if a crash occurs when using 

the road system, and that it is a shared 

responsibility of all parties involved to 

achieve this outcome. For road design, a 

Safe System Approach involves managing 

the circumstances of crashes such that 

the kinetic energy forces imposed on the 

human body should not result in death or 

serious injury. At an intersection, this is 

accomplished by influencing conflict points, 

speed, and crash angles, and considering 

exposure and complexity.

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Crashes attributed to intersections 

contribute significantly to traffic fatality 

and injury numbers in the United States. 

In 2019, 10,180 people were killed in 

intersection and intersection-related 

crashes, which is roughly one-quarter of 

all roadway fatalities. Additionally, about 

half of all injury crashes occur at or near 

intersections. Intersection projects represent 

a straightforward opportunity to explore 

how to apply Safe System principles to the 

project development planning and design 

decisions in support of Vision Zero, as well 

as a performance-based approach to safety.

FHWA sponsored the effort to develop a 

Safe System for Intersections (SSI) frame

work and methodology, which represents a 

first step toward the development of objec

tive and implementable analyses that reflect 

key Safe System concepts. The Safe System 

assessment of an intersection can serve as 

an additional metric to inform alternatives 

analysis and identify an optimal solution for 

an intersection. In fact, the SSI method can 

provide a valuable quantitative safety metric 

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14 | PUBLIC ROADS | WINTER 2022

in addition to, or in the absence of, the 

types of crash-based approaches that are the 

foundation of the Highway Safety Manual.

Bonnie Polin, a State safety engineer 

from the Massachusetts Department of 

Transportation (MassDOT), says, “We had 

an opportunity to test out the SSI approach 

to evaluate design alternatives for two irreg

ular, nontypical intersections where safety 

performance function models were not 

available. The SSI method, along with other 

approaches such as road safety audits and 

video analytics using drone technology, can 

help us gain a more complete safety perfor

mance picture to help us identify a preferred 

alternative that reduces risk and minimizes 

the potential for harm.”

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Explanation of the SSI Method

The SSI method uses data that are typically 

available early in a project development 

lifecycle, including posted speed limit, 

average annual daily traffic volumes, and the 

number of through lanes on the intersecting 

roads. When available, several optional 

inputs—such as individual movement 

speeds, daily nonmotorized volumes, 

turning movement proportions or volumes, 

and left-turn traffic signal phasing—can be 

incorporated to enhance the analysis. The 

SSI method offers assumptions and default 

values, but agency-prescribed or projectspecific values could also be used.

The overall framework and components 

of the SSI method are based on conflict 

point identification and classification, expo

sure, severity, and complexity. With these 

inputs, it is possible to quantify the degree 

to which a given intersection alternative is 

consistent with Safe System principles, and 

then contrast different alternatives.

-

The SSI method begins with the identi

fication and classification of conflict points 

for each intersection alternative. Since exact 

lane arrangements may not be known at the 

project development stage, the SSI method 

identifies conflict points on a movement 

basis. A conflict point is any location where 

road users’ paths coincide, categorized 

as either crossing, merging, diverging, or 

nonmotorized. This first version of the 

SSI method assigns both pedestrians and 

bicyclists to the same path through the 

intersection, but future enhancements to the 

method could incorporate additional layers 

of vehicle-bicycle conflict points depending 

on the selection of bicycle accommodation 

through the intersection, such as those 

described in the FHWA Bikeway Selection 

Guide (FHWA-SA-18-077). The SSI 

method also does not currently consider 

rear-end conflicts that result from traffic 

congestion or deceleration/stopping because 

of traffic control devices, but does consider 

rear-end conflicts that result from speed 

differentials at diverging conflict points 

where vehicles making different movements 

have different speeds.

-

Once the conflict points are identified 

and classified, the SSI method characterizes 

exposure, which is the crash likelihood at 

a given conflict point given the number of 

vehicles or nonmotorized users that pass 

through it. To do this, the SSI method 

employs an exposure index, adapted from 

past research. The first step involves calcu

lating the product of crossing movements, 

using vehicle or nonmotorized user daily 

volumes, through each conflict point. The 

second step is to sum the results across all 

conflict points of each type at an intersec

tion to compute total exposure for each 

conflict point type.

-

-

This diagram illustrates the movement-based conflict points for a traditional four-legged, all-movements intersection.

Source: FHWA.

This diagram indicates some of the conflicting lane considerations for a left-turn movement from a minor road to a major 

road at a traditional intersection.

Source: FHWA.

Next, conflict point severity is the 

estimated probability of at least one fatal 

or serious injury, or P(FSI), resulting from 

a crash between conflicting road users 

making the movements that define the 

conflict point. The SSI method defines 

serious injury as an injury with a Maximum 

Abbreviated Injury Scale score of 3 or 

above. The SSI method estimates P(FSI) at 

crossing, merging, and diverging conflict 

points using an estimated speed for each 

conflicting movement and an estimated 
WWW.FHWA.DOT.GOV | 15

angle between conflicting movements. 

For nonmotorized conflict points, the SSI 

method only requires the vehicle speed at 

the conflict point to compute P(FSI). The 

full report for this project offers additional 

detailed explanation of the basis and steps 

for calculating P(FSI).

Finally, the SSI method accounts for 

movement complexity using adjustment 

factors that relate to the conflicting traffic 

scenarios. The conflicting traffic complexity 

factor is based on the relative complexity 

due to traffic control (such as permissive 

versus protected signalized movements), 

and, for all movements, the number of 

conflicting lanes and the speed of conflicting 

traffic. The nonmotorized movement 

complexity factor addresses complexity 

specific to nonmotorized movements 

through the intersection by accounting for 

indirect and nonintuitive movements at an 

intersection that may present additional 

complexity for pedestrians and cyclists. 

Taken together, the movement complexity 

factors represent a human factors approach 

that considers the potential workload 

imposed on road users as they make specific 

movements through the intersection.

The SSI Score

The first step in determining the SSI score 

is to compute the sum of the exposureseverity-complexity products for all indi

vidual conflict points of a specific type and 

to apply the appropriate adjustment factors. 

The second step is to convert that computed 

value to a score that has a range of 0 to 

100, with 100 representing the best score 

possible, equating to the lowest probability 

of a fatality or serious injury in the event 

of a crash. The method produces an SSI 

score for each conflict point type (such as 

crossing, merging, diverging, nonmotorized) 

as well as for the intersection overall. The 

SSI method also yields relative scores 

for exposure, severity, and complexity in 

order to provide additional context to the 

SSI scores.

-

Example Application 

of SSI Method

The example intersection is a signalized 

suburban intersection of a four-lane major 

road and a two-lane minor road. Design 

year traffic volumes are estimated at 25,000 

and 20,000 vehicles per day, respectively, 

on the major and minor roads. The posted 

speed limits are 45 miles (72 kilometers) 

per hour on the major road and 35 miles 

(56 kilometers) per hour on the minor. 

There are sidewalk facilities along all 

approaches, and the 

intersection serves a daily 

volume of 2,400 nonmo

torized road users.

-

First, a Stage 1 Inter

section Control Evalua

tion (ICE) assessment is 

completed using the Safety 

Performance for Intersec

tion Control Evaluation 

(SPICE) and Capacity 

Analysis for Planning 

of Junctions (CAP-X) 

screening tools (both 

tools and user guides are 

available at 

-

-

-

https://safety

.fhwa.dot.gov/intersection

/ice). ICE is a data-driven, 

performance-based frame

work to screen intersection 

alternatives and identify 

an optimal solution, and 

SPICE and CAP-X are 

screening-level tools used 

to characterize safety and 

operational performance. This assessment 

produces 11 possible alternatives, including 

ones that the screening tools did not 

explicitly model. As a means to a quantita

tive safety metric when crash-based models 

are not available, this is an area where the 

SSI method can be immediately helpful. 

After the SPICE and CAP-X assessments, 

the SSI method was applied to these 11 

different intersection alternatives to produce 

SSI scores.

-

-

The SPICE results for the example 

application contain the predicted number 

of crashes for the design year for both total 

crashes (all types and severities) and fatal 

and injury crashes unless there is not an 

appropriate safety performance function 

available, as in the case of the 2x2 round

about. The results show that all the inter

section types for which there are predictive 

methods available have fewer total and fewer 

fatal and injury crashes than the signalized 

traditional intersection that is the no-build 

condition. Based on these SPICE results, 

no intersection alternatives are dropped 

from consideration.

-

-

The existing layout (no-build option) of the example intersection is a signalized 

suburban intersection of a four-lane major road and a two-lane minor road, with 

the respective speed limits and annual average daily traffic (AADT) indicated.

Source: FHWA.

Results from the SPICE tool for the example SSI application.

Intersection Type

Predicted Fatal & Injury 

Crashes Per Year

Predicted Total Crashes 

Per Year

Unsignalized RCUT 0.53 1.69

Median U-Turn 1.24 4.08

Jughandle 1.31 3.55

Signalized RCUT 1.38 4.08

Full Displaced Left Turn 1.55 4.22

Signalized Traditional 

(existing) 1.77 4.80

2x2 Roundabout No safety performance 

function 2.29

2x1 Roundabout* -- --

Quadrant Roadway* -- --

Partial Displaced Left Turn* -- --

Bowtie* -- --

* These intersection types are not included in SPICE, but are 

included in the SSI library of intersections.
16 | PUBLIC ROADS | WINTER 2022

CAP-X primarily assesses intersection 

types by using critical lane analysis to 

compute the volume-to-capacity ratio given 

vehicle volume inputs and intersection 

lane arrangements. Based on these results, 

it can be seen that all but the unsignalized 

restricted crossing U-turn (RCUT) intersec

tions would be operationally similar to or 

better than the existing signalized traditional 

intersection. Otherwise, all these alternatives 

are operationally feasible.

-

Based on the SSI scores for individual 

conflict point types, seven alternatives 

have improved SSI scores for the nonmo

torized conflict points compared to the 

signalized traditional intersection (which 

is the existing/no-build condition). Eight 

alternatives have improved crossing conflict 

SSI scores compared to the no-build 

alternative: partial multilane (2x1) round

about, median U-turn, full multilane (2x2) 

roundabout, signalized RCUT, bowtie, 

unsignalized RCUT, full displaced left 

turn, and partial displaced left turn. These 

designs reroute one or more movements at 

the intersection, removing crossing conflict 

points, reducing vehicle speeds and angles 

at crossing conflict points, or both. Because 

the SSI method is sensitive to conflict 

point speed, for alternatives that do not 

afford nonmotorized users the benefit of 

either low speed through geometry (such 

as a roundabout) or separated movements 

through traffic control phasing (such as the 

signalized alternatives), the nonmotorized 

conflict scores can be as low as zero.

-

-

-

Results from the CAP-X tool for the example SSI application.

Intersection Type Overall Volume-to-Capacity Ratio

Quadrant Roadway 0.25

Full Displaced Left Turn 0.27

Median U-Turn 0.31

2x2 Roundabout 0.31

Partial Displaced Left Turn 0.32

Bowtie 0.40

Signalized Traditional (existing) 0.44

Signalized RCUT 0.48

2x1 Roundabout 0.53

Unsignalized RCUT 0.85

Jughandle* --

* The Jughandle intersection is not included in CAP-X, but it has the capacity to handle high 

intersection volumes.

Results of SSI method calculations for the example SSI application.

Intersection Type

Overall 

Intersection 

SSI Score

Nonmotorized 

Conflict SSI Score

Crossing Conflict 

SSI Score

Merging Conflict 

SSI Score

Diverging Conflict 

SSI Score

2x1 Roundabout 52 8 93 98 100

Median U-Turn 44 10 52 83 88

2x2 Roundabout 42 4 90 98 100

Signalized RCUT 40 5 74 77 86

Bowtie 31 4 23 94 96

Quadrant Roadway 30 6 14 93 94

Jughandle 27 3 18 93 97

Signalized Traditional 

(existing) 24 2 19 93 100

RCUT 19 0 65 69 86

Full Displaced 

Left Turn 10 0 32 91 97

Partial Displaced 

Left Turn 9 0 26 91 97

With the SPICE, CAP-X, and SSI results 

available, the alternatives can be compared 

and contrasted further to make a recom

mendation on which preferred alternative(s) 

should be carried forward into the next 

phase of project development. Alongside the 

SPICE and CAP-X results, the SSI scores 

point to the “hybrid” 2x1 roundabout or 

the 2x2 roundabout as the most appealing 

alternatives. That roundabouts would 

compete so well based on Safe System prin

ciples supports the international literature 

and experience on both the Safe System 

Approach and roundabouts.

-

-

The unsignalized RCUT shows prom

ising SPICE results in terms of predicted 

total crashes and predicted fatal and injury 

crashes and SSI method scores that are 

comparable to the existing traditional 

signalized, except for a particularly poor 

nonmotorized conflict score of zero that 
WWW.FHWA.DOT.GOV | 17

brings the overall SSI score down as well. 

This highlights the importance of giving 

nonmotorized users greater attention and 

accommodation at certain alternative 

intersections that have otherwise been 

proven to offer significant enhanced safety 

performance. It is likely that an unsignal

ized RCUT alternative that reduces speed 

through nonmotorized conflict points and 

eliminates indirect or nonintuitive move

ments could achieve a much better SSI 

method score and preserve or even enhance 

the safety performance that has been 

documented through crash-based studies.

-

-

This diagram illustrates both vehicular and pedestrian movement-based conflict points associated with roundabout 

intersections based on the SSI method.

Source: FHWA.

Future SSI Applications

While U.S. intersection planning and design 

practices have incorporated Safe System 

principles to some extent over the last 

several decades, significant opportunities 

for advancing the Safe System Approach 

remain. In addition to MassDOT, other 

State DOTs are also evaluating the SSI 

method for their intersection projects, 

including California, Florida, Washington, 

and Virginia.

Stephen Read, the safety planning 

program manager for the Virginia DOT, 

says, “While Virginia is updating [its] Stra

tegic Highway Safety Plan to be more Safe 

System centric, VDOT’s Traffic Engineering 

Division is conducting a review of the SSI 

method to determine whether it could 

be incorporated into a new Intersection 

Control Evaluation program that is also 

under development.”

-

Where enough data are available, U.S. 

experiences with intersection alternatives 

that simplify road user decisionmaking 

and manage conflict points, impact angles 

and speeds have shown safety performance 

benefits. These safety benefits are typically 

expressed in the form of crash modification 

factors (CMFs) derived from retrospective 

statistical analyses of crash data. The CMFs 

are usually applicable to the intersection 

as a whole and reflect overall changes or 

differences in the number of crashes at the 

intersection alternative of interest compared 

to another intersection alternative. In 

other words, intersection CMFs are often 

developed with and applicable to an aggre

gation of crashes resulting from different 

movements through the intersection, 

involving different intersection users, and 

resulting in a range of injury outcomes. For 

example, intersection CMFs for fatal and 

injury crashes apply to crashes of all types 

with injury outcomes ranging from fatal to 

possible injuries.

-

As a complement to aggregate crashbased findings such as CMFs, the SSI 

method provides an approach to characterize 

intersection alternatives with respect to the 

Safe System principles of managing impact 

angles and speeds and simplifying decision

making, with the goal of reducing traffic 

fatalities and serious injuries. The method 

is applied at the conflict point level and 

incorporates the characteristics of different 

movements through the intersection for all 

road users. The SSI method is sensitive to 

volumes, vehicle speeds, potential collision 

angles, and geometry.

-

The results of applying the SSI method 

include multiple measures of effectiveness 

and a set of SSI scores that can serve as 

additional safety metrics to inform the 

process of screening intersection alterna

tives, such as during a Stage 1 Intersection 

Control Evaluation. Continued advance

ments in crash reporting, injury surveillance 

(including linkages between crash reports 

and hospital records), and more widespread 

availability of vehicle movement and speed 

data will enable more empirical connections 

to be made between SSI scores and fatal and 

serious injury crash data.

-

-

JEFFREY SHAW, P.E., is the Intersection Safety 

Program Manager and member of the Safe System 

Working Group for FHWA’s Office of Safety. He 

earned his B.S. in civil engineering from the Illinois 

Institute of Technology.

R.J. PORTER, Ph.D., P.E., is a contracted highway 

safety engineer with extensive experience 

in transportation research, engineering, and 

education. He has conducted and led a range 

of research work for USDOT/FHWA, the National 

Cooperative Highway Research Program, and 

State agencies. He earned his B.S., M.E., and Ph.D. 

in civil and environmental engineering from Penn 

State University.

MICHAEL DUNN is a contracted transportation 

analyst. He specializes in pedestrian and bicyclist 

safety and the practical application of Safe 

System principles. He earned his B.S. in civil 

engineering from the University of Alabama and 

his M.S. in civil engineering from the University of 

Texas at Austin.

JON SOIKA, P.E., is a contracted senior 

transportation engineer. He has contributed 

to a variety of intersection design and safety 

projects for Federal, State, and local agencies. 

He earned his B.S. in civil engineering from Penn 

State University.

IVY B. HUANG, Ph.D., is a contracted water 

resources designer and has used her data 

analysis experience to assist in water resources 

and transportation projects. She earned her B.S. 

in civil and environmental engineering from the 

Massachusetts Institute of Technology and her 

M.S. and Ph.D. from Stanford University in civil and 

environmental engineering.

For more information, visit https://safety

.fhwa.dot.gov/intersection/ssi/fhwasa21008

.pdf for the full FHWA report or contact 

Jeffrey Shaw at 202-738-7793 or 

Jeffrey.Shaw@dot.gov.

The authors would like to thank Annette 

Gross for her contributions to this article.
18 | PUBLIC ROADS | WINTER 2022

NHTSA’s 

SAFE 

SYSTEM 

APPROACH: 

Educating and 

Protecting All 

Road Users

NHTSA’s Safe System efforts focusing on safe 

road users, safe vehicles, and post-crash care.

© ambrozinio / Shutterstock.

NHTSA supports the Safe System Approach through data-driven measures 

to make the Nation’s transportation network more secure for everyone.

by ROBERT RITTER, DEE WILLIAMS, and GAMUNU WIJETUNGE

More than 50 years ago, the Highway Safety Act of 1970 confirmed the 

commitment of the U.S. Government 

to work to protect the traveling public’s 

safety on the road. The legislation estab

lished the National Highway Traffic Safety 

Administration to help reduce the number 

of deaths, injuries, and economic losses 

resulting from motor vehicle crashes on the 

Nation’s highways. The agency’s efforts since 

then have saved hundreds of thousands 

of lives—NHTSA estimates that since 

1960, improved vehicle safety tech

nologies alone have saved more than 

600,000 people. Unfortunately, the 

Nation continues to lose too many 

family members, friends, and neighbors 

to traffic crashes. In 2020, the United 

States lost more than 38,000 people to 

traffic crashes.

-

-

“We must address the tragic loss of life 

we saw on the roads in 2020 by taking a 

transformational and collaborative approach 

to safety. Everyone—including those who 

design, operate, build, and use the road 

system—shares responsibility for road safety, 

This is the foundation of the safe system 

approach, and one that guides our lifesaving 

work at NHTSA,” says Dr. Steven Cliff, 

NHTSA’s deputy administrator.

The Safe System Approach is a datadriven, holistic, and equitable method to 

roadway safety that fully integrates the 

needs of all users, anticipates the possibility 

of errors by drivers and other road users, 

and manages crash impact forces to levels 

tolerated by the human body. The Safe 

System Approach includes five elements: 

safe road users, safe vehicles, safe speeds, 

safe roads, and post-crash care. The 

approach incorporates the 5 Es of traffic 

safety—equity, engineering, education, 

enforcement, and emergency medical 

services (EMS)—but goes beyond the 

traditional approach to enlist designers, 

operators, and users of the transporta

tion system to prevent fatal crashes and 

reduce crash severity. NHTSA’s efforts 

focus on safe road users, safe vehicles, safe 

speeds, and post-crash care.

-

The Safe System Approach principles and elements.

Source: FHWA.
WWW.FHWA.DOT.GOV | 19

The Safe System Approach broadens 

NHTSA’s scope with the tenets that safety 

is proactive and responsibility is shared. It 

challenges everyone involved to not accept 

fatalities and serious injuries as a conse

quence of mobility. Instead, the approach 

is founded in the conviction that no one 

should be killed or seriously injured while 

using the roadway system. It recognizes 

that people make mistakes, and those who 

oversee, design, and regulate the compo

nents of the transportation system have 

a responsibility to develop a system that 

accommodates mistakes. In the case where 

a crash cannot be prevented, the energy that 

dictates the injury severity, when possible, 

should be mitigated to improve survivability 

outcomes. A Safe System provides equitable, 

timely, and appropriate care.

-

-

Historically, NHTSA has always used 

a data-driven systems approach to crashes, 

related causal factors, and candidate 

countermeasures. The agency’s foundational 

work is grounded in the Haddon Matrix, 

introduced by NHTSA’s first Administrator, 

Dr. William Haddon, in 1969. The Haddon 

Matrix identifies the factors involved in 

crashes—from the pre-crash phase, crash 

phase, and post-crash phase—and how 

drivers, vehicles, and the environment influ

ence the outcomes of each. The Haddon 

Matrix embodies the core elements of 

NHTSA’s historic efforts to reduce traffic 

injuries and fatalities by using data to iden

tify traffic safety issues and employ counter

measures to target those issues.

-

-

-

NHTSA’s National Center for Statistics 

and Analysis (NCSA) supports data-driven 

decisions through the collection and analysis 

of data and the dissemination of informa

tion to quickly identify potential problems 

and support data-driven safety decisions. 

In addition to its own data sources, NCSA 

uses data from other governmental agencies, 

as well as crash files from States, to support 

analytical activities. NCSA also regularly 

publishes a variety of research notes, crash 

statistics, traffic safety fact sheets, and 

reports that provide information on crashes 

at the national and State levels (for more 

information, please see 

-

www.nhtsa.gov/data). 

NHTSA’s Haddon Matrix identifies the factors 

involved in crashes and provides examples of 

safety efforts that can influence the outcomes.

Source: NHTSA.

Factor Pre-Crash Crash Post-Crash

Human Factors • Education & licensing

• Driver impairment

• Crash avoidance 

maneuvers (braking,

turning, etc.)

• Health at time of crash

• Sitting properly

in restraint

• Impairment

• Response to EMS

• Severity of injury

• Type of injury

Vehicle/

Equipment

Factors

• Crash avoidance 

equipment & 

technology (lights, 

tires, collision 

avoidance, etc.)

• Vehicle design

• Vehicle load

• Speed of travel

• Functioning of 

safety equipment 

(seat belts, air bags, 

child restraints)

• Energy absorption 

of vehicle

• Ease of extraction 

from vehicle

• Integrity of fuel 

systems and 

battery systems

Physical

Environment

• Road hazards

• Distractions

• Weather conditions

• Roadside features

• Guardrails

• Type and size of 

object struck

• Distance of 

EMS clinicians

• Notification of 

EMS clinicians

• Accessibility to 

crash victims

Social/Economic • Enforcement activities

• Insurance incentives

• Social norming

• Ability to use 

safety equipment 

appropriately

• Laws concerning use 

of safety equipment

• Trauma system 

equipment, 

personnel, training

• Information sharing

Safe Road Users

The Safe System Approach targets the 

safety of all road users, including those who 

walk, bike, drive, ride transit, and travel by 

other modes. All road users should have 

the opportunity to travel safely, regardless 

of how they travel. At the same time, road 

users have a responsibility to operate, to 

the best of their ability, within the expecta

tions and boundaries of the transportation 

system. NHTSA works with stakeholders—

road users as well as local, State, and private 

partners—to help them understand their 

responsibilities in a Safe System. Everyone 

shares ownership of the road system and 

all share responsibility for maintaining a 

Safe System.

-

Education and training on safe road 

behaviors comprise the cornerstones of 

promoting safe road users. NHTSA works 

to reinforce positive behaviors (such as 

reminding motorcyclists to use proper safety 

gear and vehicle occupants to use proper 

adult and child restraints) and to deter 

dangerous behaviors (including impaired, 

distracted, or drowsy driving).

NHTSA develops research-based 

programs and safety campaigns that educate 

road users to drive sober, wear seatbelts, 

be attentive, and move at safe speeds. For 

example, NHTSA creates and places social, 

digital, and traditional media advertisements 

to encourage all parents and caregivers to 

use the correct car seat for their child’s age 

and weight.

NHTSA offers resources to educate and train road users on safe behaviors and equipment, including campaigns using 

the correct child safety seat for a child’s age and weight.

Source: NHTSA.
20 | PUBLIC ROADS | WINTER 2022

October is National Pedestrian Safety Month, and NHTSA and its partners run awareness 

campaigns to emphasize that all road users have a role in keeping pedestrians safe.

Source: NHTSA.

NHTSA raises awareness of the dangers 

to pedestrians by providing safety tips for 

walkers of all ages, educational material, 

statistics, resources including information 

for drivers on avoiding pedestrians, and 

conducting public campaigns, such as 

Everyone is a Pedestrian. Further, NHTSA 

has developed resources to help States and 

local communities identify, address, and 

improve pedestrian safety, including a data 

visualization tool, safety tips, and social 

media graphics and messaging. Additionally, 

NHTSA places special emphasis on people 

who walk throughout the month of October 

which is designated as National Pedestrian 

Safety Month. Everyone has a role to play 

and must work together to keep all road 

users especially our most vulnerable 

ones safe.

The Buckle Up. Every Trip. Every 

Time. campaign reminds road users 

that wearing a seat belt is one of the 

most powerful choices drivers and 

passengers can make to ensure their 

safety while in a vehicle. Proper seat 

belt use means other elements of the 

Safe System—safe vehicles and post-crash 

care—can work together to reduce fatalities 

and serious injuries.

Source: NHTSA.

Other examples of NHTSA efforts 

to educate road users include reminding 

motorcyclists to make themselves visible, to 

use motorcycle helmets that are compliant 

with U.S. Department of Transportation 

regulations, and to always ride sober. 

NHTSA helps older road users under

stand how aging and associated medical 

conditions can affect driving in addition 

to adapting a vehicle to meet changing 

physical needs. On the other end of the age 

spectrum, NHTSA provides information 

on States’ driver licensing requirements 

for novice drivers and promotes a threestage graduated driver licensing system 

and training for new drivers so that they 

understand how to safely navigate the built 

environment with other users.

-

Fair and equitable law enforcement 

is an important component in the Safe 

System Approach—not only to prevent a 

crash (supporting voluntary compliance 

with State laws) and to respond when a 

crash happens (providing emergency care, 

ensuring safety of other road users, and 

expediting scene clearance), but also as 

part of the shared responsibility to provide 

feedback to improve the system design and 

operation based on officers’ experience in 

responding to crashes. Law enforcement 

officers also serve as educators on the 

frontline to help remind all road 

users—drivers, pedestrians, bicyclists, 

transit riders, and others—to use the 

transportation system safely.

High visibility enforcement and 

education campaigns have been 

successful strategies for many decades 

at NHTSA, while supporting the Safe 

System Approach principles that safety is 

proactive and that responsibility is shared. 

The “Click It or Ticket” seat belt and 
WWW.FHWA.DOT.GOV | 21

“Drive Sober or Get Pulled Over” impaired 

driving campaigns are recognized by most 

licensed drivers. Currently, NHTSA is 

working to reduce distracted driving 

with the “U Drive. U Text. U Pay.” 

campaign. Impaired driving laws and 

the enforcement and consequences 

of these laws have worked together to 

reduce the number of impaired driving 

fatalities by half since the early 1980s.

To support its education and 

enforcement efforts, NHTSA has 

created effective partnerships with 

community and safety stakeholders to 

include health professionals, parents, 

community organizations, law enforce

ment, members of the justice system, and 

nonprofit organizations.

-

Source: NHTSA.

Safe Vehicles

The vehicle—be it a car, sport utility 

vehicle, pickup truck, heavy truck, transit 

bus, or other type—is an important compo

nent of a Safe System. Recent technological 

advances in the automotive industry provide 

a variety of tools to enhance roadway 

safety through this element of the system. 

Technology provides a key opportunity to 

address the Safe System tenet that humans 

make mistakes by supporting drivers where 

they may err and mitigate some of the 

outcomes that could result from unsafe 

behaviors. These systems, when properly 

used, can substantially reduce crashes. For 

example, automatic emergency braking 

system technologies are specifically designed 

to help drivers avoid, or mitigate the severity 

of, rear-end crashes. In 2019, almost 

one-third of all police-reported crashes 

involved a rear-end collision with another 

vehicle at the start of the crash. For more 

information, please see NHTSA’s Annual 

Traffic Safety Facts at 

-

https://cdan.nhtsa.gov

/tsftables/tsfar.htm.

Another essential aspect of a safe 

vehicle is crashworthiness—how well a 

vehicle protects its occupants in a crash. 

NHTSA’s aim is to make vehicles as 

safe as possible or their crashworthi

ness as great as possible by affording 

injury protection to occupants when a 

crash occurs. NHTSA also focuses on 

addressing the safety of those vulner

able road user populations outside 

or around the vehicle to minimize 

impact or severity of injury through 

data collection, research, and leveraging 

of new technologies. NHTSA efforts on 

vehicle crashworthiness have focused on 

new and improved vehicle design; biome

chanics and injury causation; field data 

collection; and analysis of serious injury 

cases, safety countermeasures, and equip

ment to enhance occupant safety. Despite 

modern vehicles being safer than ever, the 

need remains to improve the understanding 

of injury causation through the develop

ment and upgrade of test procedures for the 

evaluation of motor vehicle safety, the devel

opment of crash test dummies and human 

body computer models, and appropriate 

injury metrics.

-

-

-

-

-

-

NHTSA is developing the THOR (Test device for Human Occupant Restraint) 

crash dummy; the alpha model is shown here. These advanced dummies have 

more humanlike response throughout the body as well as advancements in 

instrumentation that will help assess more advanced restraint systems.

Source: NHTSA.

NHTSA’s famous test dummies Vince and 

Larry star in commercials and educational 

campaigns to warn drivers to buckle up.

Source: NHTSA.

NHTSA uses a family of crash test 

dummies to help the agency understand 

and measure the human body’s movement, 

vehicle performance, and the performance 

of various safety features during a crash. 

Measurements from the test dummies 

predict the risk of injury to each part of 

the body during air bag deployment and 

in crashes involving frontal, side, and rear 

impacts. NHTSA has dummies that differ 

in size, weight, and movement to account 

for some of the variations in body types, as 

well as crash circumstances.

NHTSA’s family of dummies ranges 

from newborns to 10-year-old children to 

small females and average males. NHTSA is 

also involved in worldwide development and 

evaluation of crash test dummies even more 

advanced than those used today. Design, 

instrumentation, and testing with these 

crash test dummies help ensure the safety of 

vehicle occupants in the unfortunate event 

that a crash occurs by encouraging safety 

improvements to vehicles to provide better 

vehicle crashworthiness through occupant 

protection—saving lives. Technologies that 

improve crashworthiness and afford protec

tion to the users include seat belts, advanced 

air bags, and electronic stability control.

-

While protecting occupants and vulner

able road users in a crash is important, the 

most desirable outcome would be to prevent 

crashes from happening whenever possible: 

-
22 | PUBLIC ROADS | WINTER 2022

no crash, no injuries, no fatalities. Advance

ments in technology have added a new 

dimension to the vehicle safety space. Active 

safety systems, which are types of advanced 

driver assistance systems (ADAS), proac

tively anticipate and assist drivers who may 

not respond to immediate and/or imminent 

dangers around them. These technologies 

include automatic emergency braking 

system technologies and electronic stability 

control—both referred to as active safety 

systems—to provide momentary interven

tion during potentially hazardous situations.

-

-

-

There are a variety of other passive 

ADAS technologies available in the market

place now. Passive ADAS technologies alert 

drivers of potential risk situations to give 

the driver time to respond. Some examples 

of these systems include forward collision 

warning, which detects a potential colli

sion with a vehicle ahead and alerts the 

driver (some systems also provide alerts for 

pedestrians or other objects); lane departure 

warning, which monitors a vehicle’s position 

within the driving lane and alerts the driver 

as the vehicle approaches or crosses lane 

markers; and blind spot warning, which 

detects vehicles in the blind spot while 

driving and notifies the driver to their pres

ence (some systems provide an additional 

warning if the driver activates the turn 

signal). Note that these systems only provide 

a warning to the driver and do not take 

action to avoid a crash.

-

-

-

The benefits of these various active and 

passive safety systems are well documented 

in helping drivers avoid or mitigate crashes, 

but they can only address a portion of 

related crash circumstances. It is vital to 

emphasize that drivers will continue to share 

driving responsibilities for the foreseeable 

future and must remain engaged and atten

tive to the driving task and the road ahead.

-

Newer vehicle innovations under 

testing and development, such as Auto

mated Driving Systems that at maturity 

contemplate replacing human drivers, 

also follow the Safe System principles and 

involve all stakeholders early and often, as 

an opportunity to contribute to the Safe 

System Approach.

-

Active safety systems like automatic emergency braking 

technology can assist drivers and prevent crashes.

Source: NHTSA.

Post-Crash Care

Even with improvements in all components 

of the Safe System Approach—roads, 

vehicles, and road users—traffic crashes still 

happen. A comprehensive and integrated 

post-crash care system can further reduce 

fatalities and serious injuries resulting from 

those crashes. 911 emergency communi

cations centers, first responders and highly 

trained EMS personnel, emergency depart

ments, and trauma centers are all essential 

parts of that system.

-

-

The actions taken after a crash are vital 

to reducing death and disability. Improve

ments to EMS systems, such as automated 

communication of crash location and 

severity, may reduce the 40 percent of 

deaths from traffic crashes that occur after 

the arrival of EMS at the crash scene. The 

information collected by 911 telecommu

nicators and EMS clinicians also serves 

as a robust resource for examining the 

factors that influence traffic crashes and 

patient outcomes.

-

-

NHTSA has integrated post-crash 

considerations in its work since the very 

beginning. NHTSA’s Office of Emergency 

Medical Services was part of the group of 

EMS stakeholders that developed standard 

curricula for EMS clinicians, the National 

EMS Information System (NEMSIS), and 

evidence-based guidelines for prehospital 

care. NHTSA also maintains EMS.gov and 

911.gov, which serve to educate and inform 

the general public, EMS, and 911 stake

holders about critical issues.

-

-

-

Today, NHTSA continues to collabo

rate with partners to advance post-crash 

care. A key component of post-crash care 

is the National EMS Education Stan

dards. The standards support consistency 

in EMS care across the country. NHTSA 

also funds the development of several 

evidence-based guidelines for clinical care, 
WWW.FHWA.DOT.GOV | 23

including guidelines for bleeding control, 

pain management, and the appropriate 

triage of trauma victims to ensure that the 

right patients get to the right hospital at the 

right time.

Post-crash care, including the sharing of 

information like crash location and injury 

severity with responding emergency personnel, 

is critical to improving patient outcomes.

Source: NHTSA.

The NEMSIS establishes a common data 

standard used by EMS systems throughout 

the country. When EMS clinicians respond 

to a 911 call and treat a patient, they 

complete an electronic patient care report 

that uses the NEMSIS standard. This 

common NEMSIS language enables infor

mation to be easily combined for surveil

lance, analysis, and research. The National 

EMS Database collects NEMSIS data—via 

State repositories—in near real time. In 

2020, EMS systems in 50 States and terri

tories submitted more than 43 million EMS 

records. The National EMS Database can 

provide information on nearly every 911 

activation for a medical emergency or injury, 

making it a powerful tool for studying 

everything from the COVID-19 pandemic 

to pedestrian injuries to vehicle crashes.

-

-

-

NHTSA also houses the National 911 

Program, which supports the advancement 

of 911 systems across the country. The 

program works with stakeholders to ensure a 

smooth transition to an updated 911 system 

to leverage new technologies. The program 

also administers a 911 Grant Program, 

which has awarded more than $100 million 

to States and Tribal nations.

In Conclusion

“NHTSA believes in an approach that is 

people-focused, meaning that infrastruc

ture serves the needs of its users, not the 

other way around. As we continue to move 

forward [with] a Safe System Approach, we 

will not forget the voices of those who use 

the roads, particularly those in communities 

of color, underrepresented communities, 

and people with disabilities. A successful 

Safe System Approach respects all users,” 

Dr. Cliff says.

-

All system managers, owners, designers, 

and users need to be actively involved in 

advancing and preserving the safety of 

the system. Everyone plays a role—from 

community and advocacy organizations to 

public safety officials and transportation 

experts, road users, vehicle designers and 

developers, law enforcement, and first 

responders. Building a Safe System requires 

an extraordinary commitment to commu

nity engagement. System users need to be 

involved in decisions before building the 

road system, in education on how to use 

it, and in reinforcing public trust that the 

system will be safe for users when everyone 

shares responsibility for it. And, most 

important, when assessing Safe System 

decisions, NHTSA will integrate the input 

and needs of all road users—not just drivers 

and passengers but pedestrians, cyclists, 

children, older Americans, and people with 

disabilities—as the Nation moves forward.

-

ROBERT RITTER is the director of the Office of 

Impaired Driving and Occupant Protection at 

NHTSA, where he works to reduce the incidents 

of alcohol and drug-impaired driving, increase 

seat belt and child safety seat use, and reduce 

distracted and drowsy driving. He is a licensed 

civil engineer and holds a master’s degree in 

transportation from Morgan State University 

and bachelor’s degrees in civil engineering from 

Rutgers University School of Engineering and 

in religion from Rutgers College (now part of the 

Rutgers University School of Arts and Sciences).

DEE WILLIAMS is the deputy associate 

administrator for NHTSA’s Office of Vehicle 

Safety Research. She leads the development of 

vehicle safety research and policy initiatives to 

advance national highway traffic safety programs, 

innovative technologies, and motor vehicle safety 

standards. She holds a B.A. in political science 

from Susquehanna University.

GAMUNU WIJETUNGE has served as an EMS 

specialist within the Office of EMS at NHTSA 

since 2001. His main responsibilities include 

disaster preparedness, air medical issues, the 

EMS workforce, and development of clinical 

evidence-based guidelines. An active paramedic 

and firefighter, he holds a B.S. in emergency 

health services from the University of Maryland, 

Baltimore County and a master’s degree in public 

management from the University of Maryland, 

College Park. He would like to thank Michael Gerber 

for his contributions to this article.
24 | PUBLIC ROADS | WINTER 2022

Speed management is a critical element 

of the Safe System Approach.

© Joshua Fulle / Unsplash.com. 

SPEED 

MANAGEMENT Is Key to Road Safety

Advancing speed management for safety can reduce speeding-related 

injuries and fatalities on the Nation’s highways and byways.

by GUAN XU, ABDUL ZINEDDIN, RANDOLPH ATKINS, and SARAH ABEL

Much progress has been made in transportation safety over the last several decades. Despite the large increase in traffic volume, 

the fatality rate decreased from 5.5 fatalities per 100 million vehicle 

miles traveled (VMT) in 1966 to 1.11 fatalities in 2019. Despite 

this success, reducing traffic speeds and speeding-related crashes and 

fatalities continue to pose some complex challenges. Early estimates 

show that fatality rates and speeding-related fatalities increased in 

2020 during the COVID-19 public health emergency, compared to 

2019, although 2020 was anomalous.

Studies clearly show that higher speeds result in greater impact at 

the time of a crash, which leads to more severe injuries and fatalities. 

This is especially concerning for more vulnerable road users, such as 

motorcyclists, bicyclists, and pedestrians. Per vehicle miles trav

eled in 2019, motorcyclist fatalities occurred nearly 29 times more 

frequently than passenger car occupant fatalities, and 33 percent of 

motorcycle riders involved in fatal crashes in 2019 were speeding. 

Pedestrians made up 17 percent of traffic fatalities in 2019 with 

6,205 fatalities. Bicyclists accounted for approximately 2 percent of 

fatalities in 2019 with 846 bicyclist fatalities.

-

The greater the speed of a vehicle at the time of a crash, the higher the risk of death for 

a pedestrian struck.

Source: Federal Highway Administration. Based on data from the 

AAA Foundation for Traffic Safety, Impact Speed and a Pedestrian’s 

Risk of Severe Injury or Death, September 2011.

Because higher speeds increase fatalities, new approaches 

in speed management, such as the Safe System Approach, are 

needed to reduce roadway fatalities and increase the safety of all 
WWW.FHWA.DOT.GOV | 25

road users. Underscoring the importance 

of this issue, the National Transporta

tion Safety Board has identified both 

“implement a comprehensive strategy to 

eliminate speeding-related crashes” and 

“protect vulnerable road users through 

a Safe System Approach” as part of its 

2021–2022 Most Wanted List of trans

portation safety improvements (found at 

-

-

www.ntsb.gov/safety/mwl/Pages/default.aspx).

Speeding as a Safety Problem

The National Highway Traffic Safety 

Administration defines a crash as speedingrelated if any driver involved in the crash is 

charged with a speeding-related offense or if 

a police officer indicates racing, driving too 

fast for conditions, or exceeding the posted 

speed limit was a contributing factor in a 

crash. The most recent data from NHTSA’s 

Fatality Analysis Reporting System (FARS) 

found that, in 2019, there were 9,478 

speeding-related fatalities, 26 percent 

of total traffic fatalities for the year. For 

speeding-related fatalities where functional 

class was reported, 86 percent occurred on 

noninterstate roadways. Drivers in speed

ing-related fatal crashes were more likely 

to have previous convictions for speeding 

and/or alcohol-impaired (BAC .08 g/dL or 

higher) driving, previous crashes, and license 

suspensions or revocations compared to 

nonspeeding drivers in fatal crashes.

-

Speed feedback signs like this one can encourage drivers 

to follow posted speed limits and advisory warnings.

© Portland State University.

NHTSA’s nationally representative 

survey of traffic speeds across the United 

States conducted in 2015 revealed that 70 

percent of free-flow vehicles on limited 

access roads exceeded the posted speed 

limit, with 59 percent of vehicles on major 

arterials and 60 percent of vehicles on minor 

arterials and collector roads also exceeding 

the posted speed limit. The 85th percentile 

speeds were significantly higher in 2015 

on major arterials and minor arterials and 

collector roads as compared to the previous 

national survey in 2009. The full survey is 

available at https://rosap.ntl.bts.gov/view

/dot/35961.

The COVID-19 public health emer

gency made excessive speeding behaviors 

more evident. Traffic speeds across the 

country increased during this same period 

compared to historical levels, especially 

on urban interstates, with many reports of 

drivers traveling at extremely high speeds 

in excess of 100 miles (160 kilometers) 

per hour. In 2020, while VMT decreased 

13.2 percent, the fatality rate increased 

to 1.37 fatalities per 100 million VMT, 

up from 1.11 in 2019, with a projected 

7.2 percent increase in fatalities and an 

11 percent increase in speeding-related 

fatalities. The evidence indicates that a 

combination of less congested roads and a 

higher percentage of riskier drivers contrib

uted to this increase.

-

-

Many factors contribute to drivers’ 

choice of speeding, but drivers’ beliefs and 

attitudes play an important role in their 

driving behavior and the cultural acceptance 

related to speeding. For instance, NHTSA’s 

naturalistic driving study, “Motivations for 

Speeding,” showed that driver motivations, 

attitudes, and beliefs are “highly significant 

predictors” of which drivers speed and how 

much they speed. Several studies identified 

speed-contributing attitudes such as being 

impatient with other drivers, wanting to 

get where they are going as fast as possible, 

enjoying driving fast, and believing 

that driving fast was not dangerous for 

skilled drivers.

Transportation professionals have real

ized that creating a positive traffic safety 

culture is critical to addressing speeding 

as a safety problem. All five elements of 

the Safe System Approach can be applied 

to addressing speeding; however, the safe 

speeds and safe roads elements are of partic

ular importance when creating a successful 

speed management program and advancing 

speed management for safety.

-

-

SAFE SYSTEM ELEMENTS

Safe speeds is one of the five elements of the Safe System Approach. Applying safe speeds reduces impact forces, 

increases visibility and decreases stopping distance.

Source: FHWA.

The Importance of 

Speed Management

When drivers are traveling at higher speeds, 

they require more time to react once they 

see changes in the road environment ahead. 

Once they engage the brakes, the distance 

required to stop the vehicle is directly 

related to the speed of the vehicle at the 

time of braking and the vehicle’s weight; 

higher speeds and heavier vehicles simply 

take longer to stop, so consequently these 

factors result in the increased probability 

of crashes. Speed also impacts the severity 

of a crash. The force involved in a crash 

is directly related to the speed at the time 

of a crash: “The energy release is propor

tional to the square of the impact speed,” 

according to the Transportation Research 

Board’s Special Report 254: Managing Speed 

– Review of Current Practice for Setting and 

Enforcing Speed Limits. These factors show 

how effective speed management using the 

Safe System Approach, defined as kinetic 

energy management, can contribute to 

reducing speeding-related serious injuries 

and fatalities.

-

Speed management is an approach that 

focuses on achieving safe mobility by setting 

appropriate speed limits, reducing speeding, 

and reducing and/or mitigating the impact 

of speeding-related crashes. The goal of the 

U.S. Department of Transportation speed 

management program is to improve public 
26 | PUBLIC ROADS | WINTER 2022

health and safety by reducing speedingrelated fatalities and injuries and achieve 

improved safety experience for all road 

users. The following key speed management 

strategies and activities for achieving the 

USDOT speed management program goal 

were identified by the USDOT intermodal 

Speed Management Team that consists of 

NHTSA, FHWA, and the Federal Motor 

Carrier Safety Administration:

• Developing and implementing 

jurisdiction-wide speed management 

programs and plans.

• Outlining how to set safe, consistent, 

and enforceable speed limits based 

on the presence of all road users 

and context and not just drivers’ 

operating speeds.

• Applying proven safety 

countermeasures to help achieve 

safe speeds for the safety of all 

roadway users.

• Improving crash data report forms 

with targeted reporting of speedingrelated crashes that provides 

consistency and focuses on identifying 

contributing factors.

• Deploying enforcement through 

transparent high-visibility activities, 

educational programs, and awareness 

campaigns rather than a strictly 

enforcement focus.

• Considering equity in speed 

management decision making.

The team is currently updating the 

USDOT Speed Enforcement Camera Systems 

Operational Guidelines. The updated guide is 

expected to be renamed Speed Safety Camera 

Program Planning and Operations Guide and 

will emphasize that speed cameras are an 

effective countermeasure to improve safety 

by managing traffic speeds.

Noteworthy safety programs recognize 

safe speeds as a key factor to achieving a goal 

of zero traffic deaths and serious injuries. 

All zero-death programs reference the Safe 

System Approach for achieving safe speeds, 

and the need to create a positive traffic 

safety culture and improve driver behavior 

as a part of effective speed management.

The safe speeds element of the Safe 

System Approach can be reached through a 

comprehensive speed management program. 

There are challenges and opportunities 

when considering speed management in 

relation to the Safe System Approach. These 

include how to define safe speeds consis

tently across all contexts, how to effectively 

set safe speed limits that do not rely solely 

on driver operating speeds, how to achieve 

a target speed using roadway geometry 

effectively, and how to incorporate the 

concepts of kinetic energy forces and speed 

harmonization in existing speed manage

ment guidance. To address the challenges, a 

joint effort by FHWA and the Institute of 

Transportation Engineers (ITE) is currently 

developing additional resources as speed 

management practices shift toward applying 

the Safe System Approach.

-

-

This graph shows distance traveled for perception/reaction 

and stopping by speed. Once a driver begins reacting, 

the vehicle travels a greater distance during an evasive 

maneuver, the driver has a reduced ability to steer around 

objects in the roadway, there is an increased risk that “an 

evasive steering maneuver will result in loss of control,” 

and more stopping distance is required.

Source: FHWA.

The city of Portland, OR, has adopted a new 

speed limit of 20 miles (32 kilometers) per hour 

on nearly 70 percent of city streets as part of 

comprehensive speed management program.

© Hannah Schafer, Portland Bureau of Transportation.

FHWA: Working Toward 

Better Understanding and 

Managing of Speed

Speeding and speed management are 

cross-cutting and complex challenges 

involving the interaction of many factors, 

including effective roadway design, posted 

speed limits, political climate, road user 
WWW.FHWA.DOT.GOV | 27

behavior, enforcement strategies, and 

judicial decisions. Collaboration is the key 

to combat speeding as a safety problem. 

National agencies and organizations, such 

as FHWA, NHTSA, and ITE, provide 

resources and technical assistance on safety 

through speed management.

FHWA has been focusing on setting 

appropriate, consistent, and enforceable 

speed limits and providing technical 

assistance to State and local agencies on 

implementing effective infrastructure and 

engineering speed management counter

measures to encourage drivers to obey speed 

limits. Through its Proven Safety Counter

measure Initiatives program, FHWA is 

promoting, with technical support, the 

implementation of several proven speed 

management countermeasures including 

variable speed limit system, speed safety 

camera, and setting appropriate speed limits 

for all road users. Recently, FHWA began 

a new program to explore concepts and 

techniques to integrate the Safe System 

Approach with speed management.

-

-

Speed management is receiving increased 

attention from State and local agencies, 

especially those that have adopted Vision 

Zero goals and are beginning to implement 

the Safe System Approach. Forty-four States 

have included speeding or speed manage

ment in their Strategic Highway Safety 

Plans. A comprehensive speed management 

program is crucial to ensure that agen

cies can work collaboratively to address 

safe speeds in a holistic approach. Speed 

management program plans set objectives, 

identify gaps and needs, lay out strategies 

and planned activities, and incorporate 

state-of-practices for successfully imple

menting speed management programs. 

FHWA has been providing direct technical 

assistance and has helped some agencies 

successfully develop and implement speed 

management program plans. Some of the 

recently developed program plans include 

recommendations and strategies to help 

advance a positive traffic safety culture and 

application of the Safe System Approach.

-

-

-

In recent years, FHWA has endeav

ored to update existing, and create new, 

speed management resources for practi

tioners and provide technical assistance 

for speed management. This includes the 

recently published report, Noteworthy Speed 

Management Practices (FHWA-SA-20-047, 

-

-

https://safety.fhwa.dot.gov/speedmgt/ref_mats

/fhwasa20047/fhwasa20047.pdf), which 

includes examples of successful implementa

tions of speed management countermeasures 

by public agencies on:

-

• Developing and implementing a citywide Strategic Speed Management 

Program with comprehensive speed 

management activities, established 

key indicators, target achievement 

metrics, and an integrated effort 

including enforcement;

• Setting safe, consistent, and 

enforceable speed limits for 

all roadway users for rural and 

urban environments;

• Applying engineering and alternate 

enforcement countermeasures, such 

as self-enforcing roadway and speed 

safety cameras, to achieve the set 

posted speed limits for the safety of all 

roadway users;

• Improving crash data forms with 

targeted reporting of speeding-related 

crashes that provide consistency 

and focus on addressing crashes by 

identifying contributing factors; and

• Implementing enforcement 

through transparency and using an 

“educational” initiative rather than a 

strict enforcement detail.

In addition, FHWA has also increased 

education and training for more transpor

tation professionals on USLIMITS2, a 

web-based tool for setting safe speed limits. 

With the support of the National Coopera

tive Highway Research Program (NCHRP), 

FHWA is in the process of developing the 

next generation of the tool, USLIMITS3, 

which will incorporate state-of-the-practice 

research and methods, such as the Safe 

System Approach, for setting safe speed 

limits for all road users.

-

-

Safe speeds, one of the five elements of the Safe System Approach, are critical for all road users.

© Getty Images.
28 | PUBLIC ROADS | WINTER 2022

NHTSA Speed 

Management Activities

The efforts of NHTSA’s speed management 

program focus on the Safe System Approach 

for enforcement, education, emergency 

response, vehicle safety, and behavioral 

research to develop safety countermeasures, 

as well as providing resources and technical 

assistance to support practitioners at the 

State and local levels (www.nhtsa.gov/risky

-driving/speeding#resources). The agency 

works closely with law enforcement orga

nizations through its Law Enforcement 

Liaison Program. It also works with the 

National Institute on Standards and Tech

nology to establish model specifications for 

speed measurement devices and maintains 

a “Conforming Product List” of devices 

that meet the specifications. Additionally, 

NHTSA provides training and guidance for 

using these devices as well as other training 

for law enforcement personnel, including a 

High Visibility Enforcement Toolkit.

-

-

NHTSA provides training for traffic 

safety professionals through its speed 

management course, taught by the Trans

portation Safety Institute, and issues 

communications to educate the driving 

public on speed safety and preventing 

speeding. The agency also conducts a wide 

range of innovative research projects to 

identify safety problems; advance scien

tific knowledge in this area; and support 

the development of countermeasures to 

equitably improve speed management and 

reduce traffic crashes, injuries, and fatalities, 

including producing a report on effective 

countermeasures entitled Countermeasures 

That Work. Additionally, NHTSA supports 

emergency medical response efforts for 

crashes and offers a robust vehicle safety 

program to improve vehicle crashworthi

ness, occupant protection, and crash avoid

ance technologies.

-

-

-

-

“Speeding is one of the top causes for 

vehicle crashes,” says Nanda Srinivasan, 

NHTSA’s associate administrator for 

Research and Program Development. 

“Speeding endangers everyone—the driver, 

occupants, and other road users. There is no 

excuse to speed—whether you are late, [or] 

the roads are empty or congested.”

Ossian, IA, received a Manual on Uniform Devices experimental waiver for this high-visibility pavement 

marking to increase compliance with posted speed limit.

© Shauna Hallmark.

ITE’s Efforts in 

Speed Management

ITE continually focuses on advancing speed 

management for safety, providing updated 

resources and guidance as speeding-related 

information rapidly evolves. In 2019, 

ITE released a resource hub that includes 

available speed management resources 

helpful to transportation professionals 

(www.ite.org/technical-resources/topics

/speed-management-for-safety).

In partnership with the Vision Zero 

Network, ITE has conducted several “speed 

management for safety” workshops to 

assist agencies with implementing a safe 

and comprehensive approach to speed 
WWW.FHWA.DOT.GOV | 29

management, from helping outline program 

goals to methods for setting speed limits to 

effective roadway design to manage speeds. 

After conducting a workshop in the city 

of Austin, TX, they went on to adopt a 

comprehensive speed management program 

upon the conclusion of the workshop held 

there in 2019, and FHWA featured the 

Austin speed management program for its 

successes in the Noteworthy Speed Manage

ment Practices (FHWA-SA-20-047) publi

cation the following year. One of Austin’s 

most recent speed management successes 

took place in June 2020, when the city 

council unanimously voted to reduce speed 

limits on residential, urban arterial, and 

downtown streets.

-

-

In 2021, the Vision Zero Network 

and ITE conduced “speed management 

for safety” workshops in three California 

communities to help develop and sustain 

effective speed management safety programs 

as the state of California continues to 

look for ways to further 

advance safe speeds. Most 

recently, ITE commented 

on speed-limit-setting 

guidance in the proposed 

amendments to the 

Manual on Uniform Traffic 

Control Devices, and it is 

beginning a joint effort 

with FHWA to explore 

ways to further advance 

the Safe System Approach 

through achieving 

target speeds.

“Safe speeds are a 

key component of the 

Safe System Approach 

and critical to achieving 

Vision Zero,” says Jeffrey 

F. Paniati, P.E., ITE’s executive director 

and CEO. “An effective speed management 

program can only be created and main

tained through strong partnerships among 

those with responsibility for planning, 

design, operations, and enforcement on the 

roadway system.”

-

Looking Ahead

USDOT continues to work diligently to 

make equitable and effective speed manage

ment a priority throughout the country 

by conducting cutting-edge research and 

providing crucial resources to support 

State and local speed management efforts 

to reduce speeding-related injuries and 

fatalities. The recent commitment to the 

Safe System Approach holds great promise 

and has proven effective internationally as 

a method for setting safe speed limits and 

working toward a goal of zero roadway 

fatalities. Tackling speeding-related safety 

issues though the incorporation of new 

concepts, approaches, and technologies with 

traditional speed management can reduce 

the country’s speeding problem and improve 

overall traffic safety.

-

“We are committed to championing the 

Safe System Approach and working with our 

partners to achieve safe speeds for all road 

users,” says Michael S. Griffith, the director 

of FHWA’s Office of Safety Technologies.

Undoubtedly, there will be new chal

lenges in the future as practices advance. 

The Safe System Approach, which considers 

all road users of the transportation system 

and new technologies in vehicles and infra

structure, offers opportunity and promise 

for reducing speeding-related injuries and 

fatalities. Whatever the challenges that 

arise related to speeding, USDOT and 

its partners are prepared to address them 

through comprehensive speed management 

as part of the implementation of the Safe 

System Approach.

-

-

GUAN XU, P.E., is a highway engineer with FHWA’s 

Office of Safety Technologies, where she manages 

the Speed Management Safety program. She holds 

an M.S. in civil engineering from the University 

of Cincinnati.

ABDUL ZINEDDIN serves as the leader of the Safety 

Operations Team for FHWA’s Office of Safety. He 

provides oversight of safety issues related to 

pedestrians, bicyclists, intersections, speed man

agement, connected and automated vehicles, and 

local and rural roads. He has a B.S., M.S., and Ph.D. 

in civil engineering from Penn State University.

-

RANDOLPH ATKINS is the chief of NHTSA’s Behav

ioral Research Division. He oversees behavioral 

research on speeding, impaired driving and motor

cycle, pedestrian, and bicycle safety and has led 

numerous studies on speeding and traffic safety. 

He holds a B.A., M.A., and Ph.D. in sociology from 

the University of Virginia.

-

-

SARAH ABEL, RSP1, is the sustainable safety 

practice lead at Toole Design and was formerly 

the transportation planning director at ITE. Her 

work primarily focuses on transportation planning, 

speed management, and vulnerable road user 

safety. She serves on the steering committee of 

the National Complete Streets Coalition and on 

the Bicycle Technical Committee of the National 

Committee on Uniform Traffic Control Devices.

For more resources on speed management, 

visit https://safety.fhwa.dot.gov/speedmgt.

Speed management countermeasures for residential streets may include speed 

cushions like these, which calm vehicle traffic but include wheel cutouts that allow 

fire apparatuses to bypass in case of emergence response.

© Traffic Logix.
30 | PUBLIC ROADS | WINTER 2022

THE SAFE SYSTEM APPROACH: 

How States and Cities Are Saving Lives

The Safe System Approach offers useful tactics for saving lives and preventing fatalities on our Nation’s roadways.

by CHIMAI NGO, JOHN MILTON, LILY REYNOLDS, RACHEL CARPENTER, and CLAY VEKA

Over the past decade, many States and local communities have adopted a 

road safety goal of zero deaths and serious 

injuries. At the State level, such a goal is 

reflected in the State’s Strategic Highway 

Safety Plan (SHSP) through various brand

ings, such as Toward Zero Deaths, Target 

Zero, and Destination Zero Deaths. At 

the local level, this goal is known as Vision 

Zero. The shared belief that deaths and 

serious injuries are unacceptable is not new. 

What is new is the paradigm shift in how 

transportation agencies 

are approaching safety 

to achieve the goal of 

zero deaths.

-

Progress is not made simply through 

branding and taglines. While sharing the 

message of a commitment to zero deaths 

is important, it is most useful to know 

what agencies have done differently from 

traditional practices to achieve mean

ingful results. What is the foundation for 

these successes? For many, it is the Safe 

System Approach.

-

Countries that have institutionalized 

the Safe System Approach since the 

1990s, like Sweden and the Nether

lands, have seen the fruits of their labor. 

According to a World Resources Institute 

analysis of 53 countries, those that have 

adopted the Safe System Approach saw at 

least a 50-percent reduction in fatality rates 

between 1994 and 2015. With this encour

aging evidence, the U.S. Department of 

Transportation has taken the leadership 

role in helping to advance the Safe System 

Approach in States and local communities. 

With support from stakeholders across the 

public and private sector, implementing 

the Safe System Approach will aid in saving 

lives and preventing serious injuries.

-

-

The following are examples of how 

two States and two cities committed to 

the goal of zero deaths by employing the 

Safe System Approach to address safety 

for all road users. These States and cities 

are institutionalizing the approach and 

U.S. cities and States are adopting the Safe System Approach to address inequities 

in transportation, protect vulnerable road users, and set safer speed limits.

© Portland Bureau of Transportation.

“Vision Zero is not a slogan or a tagline. It’s 

a fundamental shift in how we approach traffic 

safety. It’s based on Safe System principles, 

starting with the ethical imperative that everyone 

has the right to move safely in their communities. 

It means using the most effective and equitable 

solutions to prioritize safe mobility for all.”

– Leah Shahum, Vision Zero Network 

Founder and Executive Director
WWW.FHWA.DOT.GOV | 31

using it as a foundation for the policies that 

affect their operations at both program and 

project levels.

Safe System: Washington’s 

Actions for All Road Users

Inspired by peer exchanges with Sweden 

and the Netherlands as well as Australia’s 

integration of Vision Zero and sustainable 

safety into the Safe System Approach, the 

Washington State Department of Transpor

tation (WSDOT) developed its first SHSP, 

Target Zero, in 2000. In doing so, Wash

ington became the first State in the Nation 

to set the goal of zero traffic fatalities. The 

multidisciplinary Safe System Approach was 

a natural next step in WSDOT’s progression 

to performance-based planning, design, and 

operations (practical solutions) within a 

multimodal system.

-

-

Early on, WSDOT focused on gaining 

leadership buy-in and support. Significant 

change initiatives often require leadership 

from the top to be effective. WSDOT 

adopted the use of executive orders to 

drive transformational changes. In 2013, 

WSDOT developed the Sustainable 

Highway Safety Program Executive Order. 

Moving Washington Forward: Practical 

Solutions followed in 2014 and led to 

changes in WSDOT engineering practices, 

providing significant design flexibility and 

including modal priority and design context 

in decisionmaking.

The agency also moved boldly to 

reorganize its structure to better define 

its hierarchy of responsibilities and activ

ities. Specifically, WSDOT created an 

Active Transportation Division to position 

walking, cycling, and other human-scale 

active modes at the same organizational 

level as transit, aviation, rail, freight, and 

central divisions, such as traffic operations, 

design, and transportation safety and system 

analysis. The new Multimodal Development 

and Delivery structure became the home 

for these divisions, which has resulted in 

greater collaboration and fostered deeper 

cross-disciplinary understanding of safety 

issues, particularly for vulnerable road 

users. Additionally, WSDOT’s Multimodal 

Technical Forum supports discussions and 

activities across these divisions.

-

 WSDOT’s safety policy initiatives 

benefit greatly from collaboration with the 

Washington Traffic Safety Commission 

(WTSC). This partnership is critical to 

advancing road safety because WSDOT 

oversees the infrastructure programing while 

the Commission is responsible for behav

ioral programing. The two agencies work 

together to update the SHSP Target Zero. 

The 2019 update included a chapter on the 

principles of the Safe System Approach, and 

the pedestrian and bicyclist safety chapter 

emphasized systemic engineering (e.g., 

narrowing lanes, road diets) and opera

tional approaches (e,g., speed management, 

enhanced traffic control, and delineation 

for active transportation) rather than the 

traditional emphasis on an individual’s 

behavior. While the 2019 SHSP Target 

Zero included a section on the Safe System 

Approach, WSDOT and WTSC expect to 

highlight the principles and elements of the 

Safe System Approach throughout the plan 

in the next update. The intent is to clearly 

outline what the Safe System Approach 

entails and what is needed from Washing

ton’s safety stakeholders, partners, and the 

public to achieve a Safe System.

-

-

-

WSDOT has now moved to integrating 

the Safe System Approach in practice by 

implementing proactive safety strategies. 

WSDOT has changed the safety program 

to de-emphasize reactive safety projects—70 

percent of its safety program funding is 

now targeted toward crash prevention. New 

safety program initiatives address two core 

components of the Safe System Approach: 

reduction of crash forces and shared 

responsibility, which encourages engineers 

to design for errors. For example, WSDOT 

aims to reduce the kinetic energy of a crash 

by installing roadside safety hardware, 

reduce crash angles by using roundabouts, 

and support shorter stopping distance by 

applying high-friction pavements.

Setting appropriate speeds is key to the 

Safe System Approach, and WSDOT’s 

Active Transportation Division and the 

WTSC’s Cooper Jones Active Transporta

tion Safety Council both provide essential 

leadership toward that goal. The Active 

Transportation Division led a multiagency 

working group that developed an injury 

minimization policy framework for speed 

setting based on human injury tolerance 

rather than the more common speedsetting methods included in the Manual 

on Uniform Traffic Control Devices. The 

principles from this approach informed a 

recent update to the agency’s Traffic Manual, 

and implementation of this policy will 

continue in 2022. New funding for speed 

management in WSDOT’s safety program 

is anticipated.

-

People walking and bicycling represent 

a disproportionate share of Washington 

State’s fatalities relative to miles traveled by 

mode, as WSDOT reports annually in its 

Gray Notebook active transportation safety 

report. Evaluation of crashes in Washington 

shows an overrepresentation of fatal and 

serious crashes involving active transporta

tion within low-income communities and 

in communities with higher proportions of 

people with disabilities or who are Black, 

Indigenous, and people of color. These same 

locations often suffer from gaps in active 

transportation facilities. This combination 

results in people walking and biking, out 

of necessity, along roadways designed for 

higher speeds and traffic volumes. Future 

funding for active transportation projects 

will be determined based on a systemic 

analysis of roadway characteristics that 

prioritizes equity. A recent update to the 

State’s active transportation plan, available 

at 

-

https://wsdot.wa.gov/construction-planning

/statewide-plans/active-transportation-plan, 

discusses these issues and provides the 

underlying methodology for identifying 

and prioritizing infrastructure gaps on 

State routes.

Active Transportation Systemic Safety Ranking Matrix 

Criterion Relevant to Gap Location Score

Safety

Crash history 0 - 5

Systemic safety issues 5 or 10

Connectivity 

(conflict reduction 

infrastructure) 

Destination proximity 0 - 10

Trail proximity 0 or 10

Intermodal proximity 0 - 10

Equity

Concentration of low income households 1 - 10

Concentration of people with disabilities 1 - 10

Concentration of people of color 1 - 10

Demand Potential for walking/cycling 0 - 10

Source: 2019 WSDOT.

Given the importance of equity in safety, 

WSDOT will be incorporating “equity by 

design” into its implementation of the Safe 

System Approach. Program and project 

choices should result in an equitable system 

that factors in the context of the road and 
32 | PUBLIC ROADS | WINTER 2022

surrounding land use and demographics. 

Understanding needs through data anal

ysis and evaluation will result in effective, 

efficient decisions and will inform modifi

cations that do not have to sacrifice safety 

for mobility.

-

-

WSDOT believes in learning from others 

through peer exchange, knowledge transfer, 

research, and innovation. WSDOT wishes 

to play an active role in implementing the 

Safe System Approach and looks forward to 

the future. “WSDOT continues to evolve 

in how it plans, designs, and operates 

the transportation system, and advance

ment toward a Safe System will be key to 

bringing deaths and serious injuries down. 

Getting to a high level of implementation 

of the Safe System will take time, but we 

are committed,” says Barb Chamberlain, 

director of the WSDOT Active Transporta

tion Division.

-

-

This “self-explaining” road design for active 

transportation users separates different road 

users to avoid conflicts and improve safety.

Source: FHWA.

Using an Equity-Informed 

Approach in Philadelphia

Philadelphia is taking an equity-informed 

Safe System Approach to eliminating 

traffic-related deaths. The ongoing effort 

seeks to create safe streets and transportation 

options for all residents.

Philadelphia has one of the highest 

rates of traffic-related deaths among major 

American cities. In 2018, the rate of 

traffic-related deaths per 100,000 residents 

was nearly triple that of New York City, 

about 50 percent greater than Chicago, and 

almost on par with Los Angeles County, 

according to the National Highway Traffic 

Safety Administration. Philadelphians also 

face high rates of unemployment, poverty, 

and inequity.

In 2016, the city responded by 

adopting Vision Zero, an initiative to 

eliminate traffic-related deaths in Phila

delphia by 2030. An action plan released 

in 2017 laid the groundwork for safe 

roadway interventions.

-

“The path to achieving Vision Zero 

is not accomplished easily and requires a 

fundamental and widespread commitment 

to systemic change from how we design our 

roads, to how we teach our kids to walk 

to school, to how we design vehicles,” said 

Philadelphia Mayor James F. Kenney in the 

Vision Zero Action Plan 2025. “It will take 

all of us to reach zero.”

The Vision Zero Task Force—a coali

tion of government officials, partner 

agencies, and community and advocacy 

groups—collaborated to introduce new 

transportation programs and policies that 

prioritize human life above all else. In these 

first 3 years, Philadelphia Vision Zero 

initiatives included 58 miles (93 kilometers) 

of completed safety projects, the launch 

of a neighborhood slow zone program, 

and the passage of legislation enabling an 

automated speed safety camera pilot on 

Roosevelt Boulevard, one of the deadliest 

roads in Philadelphia. Among the safety 

projects, the city built more than 10 miles 

(16 kilometers) of protected bike lanes, 

including a parking protected bike lane on 

Chestnut Street. Data collected before and 

after installation of the protected bike lane 

on Chestnut Street showed a 47-percent 

reduction in the number of vehicles driving 

over the speed limit during the morning 

commute and an 81-percent increase in 

people biking.

-

In 2020, Philadelphia renewed its 

commitment to Vision Zero with the 

adoption of a 5-year action plan. The Vision 

Zero Task Force shifted the city’s approach 

to a Safe System framework during a tragic 

year that saw an 82-percent increase in the 

number of Philadelphians killed in crashes 

compared to the previous 5-year average. 

Philadelphia’s Safe System Approach focuses 

on preventing fatal and serious injury 

crashes using the pillars of equity, safe 

speeds, safe streets, safe people, safe vehicles, 
WWW.FHWA.DOT.GOV | 33

and safety data. The plan is available at 

https://bit.ly/3qwNVEk.

By adopting the Safe System Approach, 

the task force aims to understand the root 

causes of crash risks across the entire road 

system and implement proactive safety solu

tions. One example is a partnership with 

researchers at the Pedestrian and Bicycle 

Information Center and the University of 

North Carolina’s Highway Safety Research 

Center to conduct a systemic analysis of 

youth pedestrian crashes to determine what 

types of street characteristics pose a higher 

crash risk. Using these results, the city can 

prioritize proactive interventions across the 

road network.

-

This plan also elevates the priority of 

slowing vehicle speeds to match roadway 

conditions. Automated speed safety cameras 

installed on Roosevelt Boulevard in 2020 

sought to discourage speeding along the 

entire corridor. Between 2013 and 2017, 

14 percent of all fatal crashes in Philadel

phia occurred on this road. Cameras at eight 

locations on Roosevelt Boulevard captured 

224,206 violations in the first month of 

June 2020. The Task Force and partner 

agencies found the number of violations 

dramatically decreased in the following 

months, resulting in a 93-percent reduction 

in violations by February 2021. Violations 

issued for vehicles traveling more than 

100 miles (160 kilometers) per hour also 

decreased, from 75 in the first month to 7 

in February 2021.This observed reduction 

in speeding is a significant step in the right 

direction to reducing risky driving behav

iors, which are directly correlated with fatal 

and serious injury crashes.

-

-

In 2020, the Vision Zero Task Force 

conducted an equity analysis of the city’s 

high-injury network, the 12 percent of 

Philadelphia roads that account for 80 

percent of all traffic deaths and serious 

injuries. The results showed fatal and serious 

injury crashes were three times more likely 

to occur in areas where most residents live 

on low incomes and 30 percent more likely 

to occur to people of color. Consequently, 

the plan made a commitment to focus 

Vision Zero efforts on low-income and 

minority neighborhoods.

Philadelphia continues to implement 

roadway interventions, including a new 

program known as Neighborhood Slow 

Zones, which focuses on traffic calming 

on residential streets and near schools. 

Construction will start in 2022 on the first 

two slow zones. The locations were selected 

through a community-driven process and 

then filtered through an equity and crash 

rate scoring system to select the first zones 

for implementation. Community members 

will collaborate with city staff to identify 

traffic safety issues and determine the 

design of the traffic calming treatments. 

This program seeks to go beyond singleblock solutions and improve safety by 

addressing entire zones within historically 

underserved areas.

In 2021 pedestrian median islands were installed in Philadelphia at all intersections on North Broad Street from Poplar 

Street to Cecil B. Moore Avenue, an intervention that has been shown have a 56-percent reduction in crashes involving 

pedestrians. North Broad Street is on Philadelphia’s High Injury Network; the corridor also connects several business 

districts and neighborhoods where a majority of residents are Black or African American.

© 2021 City of Philadelphia. Data Sources: Pennsylvania Department of Transportation crash data (2014-2018); 

U.S. Census Bureau American Community Survey Data (2013-2017). Desktop Reference for Crash Reduction Factors, 

FHWA-SA-08-011, September 2008, Table 11.

Achieving Pedestrian Safety in California

On average, approximately 3,600 people die 

on California’s road system annually. This 

represents an average of 10 deaths per day, 

and 3 of those are the State’s most vulner

able road users: people who bike and walk. 

In the United States, approximately 17 

percent of traffic fatalities are pedestrians, 

but this number is 27 percent in California.

-

These alarming numbers demanded 

action, which the California Department 

of Transportation (Caltrans) undertook 

beginning in 2020. As Caltrans Director 

Toks Omishakin said in a press release, “At 

least two pedestrians or cyclists lose their 

lives on California’s transportation system 

each day—a number we refuse to accept or 

normalize. Safety remains our top priority 

and the department will work diligently 

until the trend is reversed.”

Caltrans’ work to accelerate pedestrian 

safety began with the introduction of a 

new safety paradigm. In order to establish a 

high-level, ongoing commitment to safety, 

Caltrans made a few important organiza

tional changes to the department, including 

the establishment of a new Chief Safety 

Officer position as well as the establish

ment of a new Division of Safety Programs. 

Caltrans also incorporated four safetyfocused pillars into its 2020–2024 SHSP 

as well as the 2020–2024 Caltrans Strategic 

Plan. One of these pillars is to implement 

the Safe System Approach. The 2021 Cali

fornia State Transportation Agency’s Climate 

Action Plan for Transportation Infrastructure

details how the State recommends investing 

billions of discretionary transportation 

dollars annually to aggressively combat and 

adapt to climate change while supporting 

public health, safety, and equity, and explic

itly commits to the Safe System Approach.

-

-

-

-

The institutional commitment to the 

Safe System Approach enabled Caltrans’ 

Pedestrian Safety Improvement Monitoring 

Pilot Program, which had been piloted 

in 2016, to receive further funding and 

resources. This pilot identified and inves

tigated pedestrian-related high collision 

concentration locations and was made 

permanent in July 2020. In addition, in 

September 2020, Caltrans introduced a new 

Pedestrian Systemic Safety Improvement 

Program that addresses serious pedestrian 

injuries and fatalities before they occur 

through a combination of crash modeling, 

statistical analysis, and risk analysis. The 

program integrates Safe System elements 

and principles into a systemic approach to 

emphasize that safety is proactive and to 

further the goal of zero deaths.

-
34 | PUBLIC ROADS | WINTER 2022

Caltrans’ two pedestrian safety improve

ment programs (Pedestrian Safety Improve

ment Monitoring Program and Pedestrian 

Systemic Safety Improvement Program) 

complement each other. While the Pedes

trian Safety Improvement Monitoring 

Program’s approach is reactive in the sense 

that it focuses on locations that have a 

history of crashes, the Pedestrian Systemic 

Safety Improvement Program embodies 

many principles and elements of the Safe 

System Approach. The Pedestrian Systemic 

Safety Improvement Program advances the 

belief that safety must be proactive—

it uses crash data to identify roadways 

that suffer from recurring safety chal

lenges, but it is also proactive because 

it provides a mechanism to make 

improvements at sites that, while they 

share the same design and operational 

attributes, have not experienced 

many, or any, crashes. Both the datadriven and proactive approaches are 

needed to support pedestrian safety 

improvements throughout the State 

highway system.

­

­

­

­

To develop the Pedestrian Systemic 

Safety Improvement Program, 

Caltrans safety staff first gathered 

and compiled crash data. Then, they 

teamed up with researchers from the 

Safe Transportation Research and 

Education Center at the University 

of California–Berkeley to develop a 

pedestrian­specific systemic safety 

model. The model identifies systemic 

“hot spots,” or locations that are at 

high risk for future crashes. These hot 

spot locations are proactively selected 

not only based on locations where 

crashes have occurred but also on their 

specific features, context, and charac

teristics—providing a comprehensive, 

systemic view.

­

Once the team identified the 

systemic list, they applied a prioritization 

process to sort the locations for the most 

pressing intervention need. This prioritiza

tion process was based on multiple variables, 

including collision rate, pedestrian volume 

exposure, equity as measured by disadvan

taged communities, senior and youth popu

lation density, and school proximity. This 

analysis enabled Caltrans to make the most 

informed decisions about where California 

should invest its resources to maximize 

pedestrian safety benefits.

­

­

­

Last, traffic safety investigators imple

mented pedestrian safety countermeasures 

at the selected locations. To accomplish 

this, they relied on the Pedestrian Safety 

Countermeasures Toolbox and a companion 

training course developed by Caltrans. This 

toolbox, which includes 47 countermea

sures, helps investigators select the most 

appropriate safety countermeasure for each 

unique location.

­

­

The cover of the Caltrans publication Pedestrian Safety 

Countermeasures Toolbox.

© 2019 Caltrans.

As an outcome, in its first year, the 

Pedestrian Systemic Safety Improvement 

Program identified more than 500 loca

tions for investigation and improvements. 

Caltrans is already implementing pedestrian 

safety measures at target locations, and the 

Pedestrian Systemic Safety Improvement 

Program is currently in its second round. 

The success of the pedestrian program has 

laid the foundation for the establishment of 

additional systemic safety programs based 

on the Safe System Approach.

­

Other Caltrans safety efforts include 

establishing policies and standards on 

proven safety countermeasures, developing 

local traffic safety plans for each of the 

12 Caltrans districts in California, and 

implementing the results of a research 

project titled Developing a Safe System 

Approach to Setting Speed Limits, which is 

currently underway. In addition, Caltrans 

will partner with the California Office of 

Traffic Safety, which is providing more 

than $8 million in funding for programs 

implementing safe and equal access to 

roads for pedestrians. Finally, the Cali

fornia Transportation Commission recently 

approved $100 million for projects dedi

cated to pedestrian­focused infrastruc

ture improvements.

­

­

­

Setting Safe Speed Limits in Portland

Everyone deserves to reach their destina

tions safely. Safe driving speeds reduce the 

number and severity of crashes. Slowermoving drivers can stop more quickly to 

avoid a crash and, when a collision 

does occur, lower speeds reduce the 

chance of injury or death.

­

The city of Portland, OR, is 

actively managing driving speeds 

with a four­pronged Safe System 

Approach: lowering posted speed 

limits to support safe multimodal 

travel, redesigning streets, educating 

drivers, and enforcing speed limits 

with speed safety cameras. A notable 

success is Portland’s 5­year transition 

to setting speed limits based on the 

Safe System Approach.

Oregon sets speed limits on all 

streets in the State, regardless of street 

ownership. Speed limits on roads in 

Oregon have traditionally been estab

lished with an engineering approach 

that relies heavily on street classifica

tion and existing driving speeds, espe

cially the 85th percentile speed (the 

speed at which 85 percent of drivers 

are traveling at or below during free 

flow conditions). This approach 

typically does not adequately consider 

vulnerable road users, land uses, or 

existing infrastructure when deter

mining the posted speed limit.

­

­

­

­

Portland committed to Vision 

Zero in 2015, and yet struggled to 

reduce speed limits on its streets, in 

part because of State control of speed limit 

setting, including a speed limit request 

process that did not consider urban context 

and a lengthy review time. To address those 

barriers, the Portland Bureau of Transporta

tion (PBOT) has worked with the Oregon 

Department of Transportation (ODOT) 

and other jurisdictions to develop, test, 

and eventually adopt a speed limit setting 

process statewide that is proximate to the 

Safe System Approach, which recommends 

identifying the safest speed for all road users 

and then building infrastructure to support 

that speed.

­

In 2016, PBOT developed an alternative 

speed­setting methodology that ODOT 
WWW.FHWA.DOT.GOV | 35

agreed to pilot on nonarterial streets in Port

land. The alternative methodology identifies 

appropriate speed limits based primarily on 

street design and associated crash risk factors 

for people walking, biking, and driving, 

such as the presence and quality of bike 

lanes, sidewalks, and median separators.

-

The alternative methodology enabled 

Portland to move quickly in requesting 

that speed limits be reduced on 46 miles 

(76 kilometers) of collector streets from 

2016 to 2020. The alternative methodology 

is also simpler, which led to faster ODOT 

response times (average of 2 months instead 

of 7 months). However, most of Portland’s 

30 High Crash Network streets are func

tionally classified as arterials, and therefore 

they were not eligible for the alternative 

speed-setting method, which significantly 

limited Portland’s effort to set safe speed 

limits on its most deadly streets. Despite this 

limitation, piloting the alternative meth

odology built understanding and was an 

important step in transitioning to the Safe 

System Approach.

-

-

In 2019, ODOT convened a roundtable 

to address speed setting with participation 

from cities and counties across Oregon. 

The event took place as PBOT was advo

cating for the Safe System Approach to 

speed setting locally, and national and 

international guidance was emerging with 

similar recommendations.

-

Following the roundtable’s recommen

dations, in 2020, ODOT adopted a new 

statewide speed setting approach for all 

street classifications, including arterial 

streets. The new methodology within city 

limits primarily relies on context (land use 

density, nonmotorized activity, and infra

structure), 50th percentile speeds instead 

of 85th percentile, and setting allowable 

speed ranges for different land uses and 

street classifications.

-

-

Portland is taking two next steps to 

advance the Safe System Approach to speed 

limit setting. First, PBOT is developing 

comprehensive guidance for speed limit 

setting for Portland that will identify safe 

speed limits based on context and human 

vulnerability. Second, PBOT is working 

with ODOT to shape guidelines for new 

statewide legislation that gives Portland 

and other eligible cities authority to set 

speed limits as long as State guidelines 

are followed.

“The 5-year process that Portland has 

undertaken to transition from a traditional 

approach to speed limit setting to the Safe 

System Approach can help provide guidance 

to other jurisdictions,” says PBOT City 

Traffic Engineer Wendy Cawley. “Setting a 

vision, collaborating with partners, taking 

incremental steps, and centering a method

ology on the protection of human life are 

core elements in the process.”

-

Providing Valuable Insight

The Safe System Approach offers the neces

sary strategies for saving lives and helping 

to eliminate deaths and serious injuries 

on the Nation’s roadways. Tribal, local, 

regional, State, and Federal organizations 

have begun to integrate the approach in 

their safety programs and projects, and soon 

will expand the approach beyond the safety 

disciplines. Examples of successful programs 

from these organizations can provide valu

able insights for others who are planning to 

advance the approach.

-

-

CHIMAI NGO is a program manager for zero deaths, 

safety culture, and transportation safety planning 

initiatives in the Federal Highway Administration’s 

Office of Safety. She holds a master’s degree in 

planning from the University of Virginia.

JOHN MILTON, Ph.D., P.E., is the State safety engi

neer for WSDOT, with 33 years of experience in 

multimodal safety. He is the chair of the Transpor

tation Research Board’s Safety Section, chair of 

the World Road Association Technical Committee 

on Road Safety, and vice chair for the Committee 

on Safety for the American Association of State 

Highway and Transportation Officials. He holds a 

doctorate from the University of Washington.

-

-

LILY REYNOLDS, AICP, is an urban planner specializ

ing in streets, sidewalks, community engagement, 

and project management. She has extensive 

experience working with diverse partners to 

build consensus around complex transportation 

projects. Currently she is the deputy director of 

complete streets in the Office of Transportation, 

Infrastructure, and Sustainability in Philadelphia. 

Lily holds a master’s degree in urban studies 

from the Simon Fraser University, Canada, and a 

bachelor of arts in geography from the University 

of British Columbia, Canada.

-

RACHEL CARPENTER, P.E., was appointed the 

California Department of Transportation’s first-ever 

chief safety officer effective January 2020. She 

is Caltrans’ highest-level subject matter expert on 

safety and manages the day-to-day operations of 

the newly established Division of Safety Programs. 

She holds B.S. and M.S. degrees in civil engineering 

from Cal Poly, San Luis Obispo and University of 

California Davis.

CLAY VEKA is the Vision Zero coordinator at PBOT 

in Oregon. She has worked in traffic safety for 

almost 15 years and has her master’s degree in 

urban design and planning from the University 

of Washington.

The authors would like to thank Barb 

Chamberlain at WSDOT; Elizabeth 

Dobbins at the Philadelphia Office of 

Transportation, Infrastructure, and Sustain

ability; Jessica Downing at Caltrans; and 

Matt Kelly at PBOT for their contributions 

to this article.

-

For more information, contact Chimai Ngo 

at chimai.ngo@dot.gov.

Mode 10 MPH ≤15 MPH ≤20 MPH ≤25 MPH ≤30 MPH ≤35 MPH ≤40 MPH ≤45 MPH ≤50 MPH

PED

Shared Roadway

5’ Sidewalk 

100% One 

Side

Sidewalk 

Both Sides; 

Curb or 

Swale; 

 8’ Separation

>8’ Separation 

 Both Sides

NCHRP 562 

Crossings: 20/Hr.

>12’ 

Separation 

Both Sides

Impermeable 

 Separation Barrier

BIKE

Shared Roadway ≤ 5’ Bike 

Lane

6’ – 7’ Bike 

Lane

Minimum 2’ 

Separation from 

Autos

Permeable 

Barrier

Impermeable 

 Separation Barrier

AUTO

Gravel 

Roadway

≤ 9’ Travel 

Lanes

10’ Travel 

Lanes, 

Bike/Walk 

Streets

10’ Travel Lanes

≤ 11’ Travel Lanes 

Angle Crash 

Mitigations 

Permeable Center Barrier; 

Roadside Object Setback or 

Shielding

Impermeable 

 Center Barrier

The alternative speed setting methodology that ODOT and PBOT piloted relies primarily on street design and crash risk 

factors for people walking, biking, and driving, compared to the traditional methodology that set speed limits based 

largely on the speeds people drive during free-flow conditions.

© 2021 Portland Bureau of Transportation.
36 | PUBLIC ROADS | WINTER 2022

Applying a 

SAFE SYSTEM 

APPROACH

Across the Globe

International countries and cities 

have successfully incorporated the 

Safe System Approach to improve 

road safety, including Sweden, 

Australia, and Oslo, Norway.

Photo illustration by FHWA. 

Highway image: © Andrey Kuzmin / 

AdobeStock.com. Country images: 

© daboost / AdobeStock.com.

Studying three examples in Sweden, Australia, and Norway can help other countries, 

including the United States, pave their way to zero deaths on highways.

by MATTS-ÅKE BELIN, ANDERS HARTMANN, MARI SVOLSBRU, BLAIR TURNER, and MICHAEL S. GRIFFITH

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, occupa

tional 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 implemen

tation 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 wellknown American road safety expert William 

Haddon conducted in the 1960s. Knowl

edge about energy forces and tolerance has 

largely served as a basis for the development 

of the passive safety characteristics of vehi

cles 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 transporta

tion 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 scien

tist 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 

-
WWW.FHWA.DOT.GOV | 37

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 deter

mining factor is the unprotected road 

users’ tolerance level against impact forces. 

Although the knowledge is still not defini

tive, 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 interven

tions 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.

-

Promising vehicle technologies include automatic pedestrian detection and braking systems.

© Chesky / AdobeStock.com.

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 gradeseparated 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 tradi

tional approach to this problem meant 

dissemination of information to the public 

about the risks, enhancing driver educa

tion, and to some extent increasing police 

enforcement—the perception being that a 

change in motorist behavior was the solu

tion. But these strategies didn’t work.

-

-

-

This is an example of a 2+1 road in Sweden.

© Lars Ekman.

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 begin

ning 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.

-
38 | PUBLIC ROADS | WINTER 2022

© Matts-Åke-Belin. Graphic created by FHWA.

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 func

tions such as maintenance and infrastruc

ture 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 main

taining of road and railway infrastructure 

beginning in 2010.

-

-

-

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 inhabi

tants 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.

This is an example of traffic calming feature in an urban area in Sweden.

© Lars Ekman.

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 road

sides seemed to be the best way forward. 

However, early guidance on appropriate 

speed limits for different road environments 

-
WWW.FHWA.DOT.GOV | 39

based on Safe System principles and surviv

ability were met with political opposition.

-

Several states experienced early successes 

to scale up investment in safe road infra

structure 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.

-

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).

Cable barrier used along a roadside in Gunnison County, Colorado.

Source: FHWA.

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 (approxi

mately 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 under

standing 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 
40 | PUBLIC ROADS | WINTER 2022

beneficial, including the Safe System Assess

ment 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 highspeed intersections.

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 improve

ments 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 Devel

opment 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 effec

tive interventions to reduce severe crashes; 

and that Australia can eventually eliminate 

fatalities and harm from their roads.

-

This high-speed roundabout in Victoria, Australia, uses a raised platform to manage speed.

© Blair Turner.

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, poli

ticians 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 
WWW.FHWA.DOT.GOV | 41

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 count

less 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 opportuni

ties 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 neigh

bors react to changes. This strategy helps 

lower tensions in projects where public 

discourse can reach heated levels.

-

-

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.

© Geir Anders Rybakken Ørslien, 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.

© City of Oslo.

Traffic safety improvements are stan

dard 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 contin

uous. 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.

-

-

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 
42 | PUBLIC ROADS | WINTER 2022

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.

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 anonymiza

tion 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.

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.

© City of Oslo.

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.

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.

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.

© Geir Anders Rybakken Ørslien, City of Oslo.
WWW.FHWA.DOT.GOV | 43

ALONG THE ROAD

Metallic roadway litter can cause flat tires for maintenance vehicles.

© Boris Bondarchuk / AdobeStock.com.

Along the Road is the place to look for information about current and upcoming activities, developments, trends, and items of general interest to the 

highway community. This information comes from U.S. Department of Transportation sources unless otherwise indicated. Your suggestions and input 

are welcome. Let’s meet along the road.

Public Information and Information Exchange

ADOT Innovation Provides 

Maintenance Savings

The Arizona Department of Transportation (ADOT) fosters an environment of 

continuous improvement and waste reduction. 

One idea has created savings in trips to equip

ment shops and the cost of tire repairs: the 

pokey picker upper. It is a magnet attached 

to the front of an ADOT maintenance truck. 

This device hovers just above the ground, 

collecting metal pieces and shards along the 

highway shoulders.

-

-

During regular litter removal, ADOT 

found that their vehicles were getting a high 

number of flat tires. To reduce the waste 

and cost associated with flat tires, Timothy 

Mitchell, a highway operations supervisor at 

ADOT, brainstormed the idea to use a magnet 

to grab metal before it could puncture any 

tires. He affixed a 3-foot bar to the front of a 

maintenance truck and hung a magnetic bar 

from it. The device is also interchangeable, so it is easily moved 

to either the passenger or driver side of the vehicle, depending on 

where it is needed.

Crews began using the new tool in August 2020 to great effect. 

Since then, ADOT’s welder has improved upon the prototype. 

While the maintenance crew is still compiling data on the number 

of hours and costs saved by avoiding flat tires, they have noted 

that trips to the shop have dropped considerably. Previously, crews 

were trekking to the shop two to four times a week for repairs, 

and now it’s only about two to three times a month—a substan

tial improvement.

-

ADOT’s pokey picker upper helps protect maintenance vehicles from flat tires 

caused by metallic roadway litter, saving the agency time and money.

© Arizona Department of Transportation.
44 | PUBLIC ROADS | WINTER 2022

NHTSA Launches SpanishLanguage Website

Source: NHTSA.

In September 2021, the National Highway 

Traffic Safety Administration unveiled a new 

Spanish-language website, NHTSA en Español 

(NHTSA.gov/es), to provide safety information to 

more than 62 million Spanish speakers living 

in the United States. NHTSA’s first priority 

is safety; a large portion of the agency’s work 

includes education and raising awareness of 

critical safety issues to reduce the number of 

injuries and deaths on American roadways.

NHTSA en Español is designed for the 

general Spanish-speaking public, providing 

information to make informed decisions about 

road safety. The website replicates all the 

English-language website’s consumer-facing 

topics, including recalls, vehicle safety ratings, 

impaired driving prevention, seat belt safety, 

child passenger safety, technology, and tires and 

other equipment.

The Spanish-language website also makes NHTSA’s multilin

gual Vehicle Safety Hotline number more prominent and incor

porates the agency’s existing live chat function, also now available 

in Spanish.

-

-

Additionally, NHTSA will increase its outreach to Spanishspeaking media to help highlight behavioral and vehicle safety 

programs. After Mexico, the United States is the second largest 

Spanish-speaking country in the world. According to the U.S. 

Census Bureau, the Hispanic population in the United States, 

which includes people of every race, was 62.1 million in 2020, a 

23-percent increase since 2010.

NHTSA has long-standing practice of providing translations of 

its safety campaigns to stakeholders and safety partners through its 

TrafficSafetyMarketing.gov website and will continue this practice by 

providing customizable templates and media material.

USDOT Celebrates the Build America 

Bureau’s 5th Anniversary

In September 2020, Deputy Transportation Secretary Polly 

Trottenberg and former Transportation Secretary Anthony Foxx 

celebrated the U.S. Department of Transportation’s Build America 

Bureau (the Bureau), marking 5 years of offering innovative 

finance programs and technical assistance to State and local part

ners across the country.

-

The anniversary event was highlighted by two major 

announcements—the Bureau’s selection of five recipients for the 

new Regional Infrastructure Accelerators (RIA)Demonstration 

Program, and its first-ever INFRA Extra project designations.

Since its creation, the Bureau has closed more than 50 loans 

totaling over $20 billion to projects in eight States and is acceler

ating the number of loans being awarded. In fiscal year 2021, the 

Bureau set records with both the number of loans and the dollar 

value, closing just under $10 billion in loans.

-

The Bureau leverages the full resources of all the modes within 

USDOT and continues to promote a culture of innovation and 

customer service. The Bureau also serves as a single entity in charge 

of USDOT credit, large scale and intermodal project development, 

and provides a single point of contact for working with USDOT 

on infrastructure finance and development.

The virtual event is available to watch at http://www.youtube.com

/watch?v=g6hOTL2WkY8.

Virtual Public Involvement Conversations Video Series

The tools and practices associated with public involvement have 

expanded and shifted over the past decade due to changes in 

communications, technologies, and lifestyles. To help practitioners 

navigate this changing environment, the Federal Highway Admin

istration developed video case studies to highlight how transpor

tation agencies are using virtual public involvement (VPI) tools 

and techniques.

-

-

The VPI Conversations Video Series (available at www.fhwa

.dot.gov/planning/public_involvement/vpi/case_studies) features short 

conversations with professionals involved in virtual public involve

ment efforts at State and local transportation agencies. The conver

sations cover such topics as institutionalizing VPI, virtual open 

houses, bilingual resources, engaging with diverse communities, 

and strategies for planning, project development, and environ

mental review. FHWA’s VPI website (

-

-

-

www.fhwa.dot.gov/planning

/public_involvement/vpi) also includes a variety of resources to assist 

State DOTs and metropolitan planning organizations with imple

menting the VPI initiative. These resources include fact sheets, 

peer exchanges, and the video case studies.

-

Source: FHWA.

ALONG THE ROAD
WWW.FHWA.DOT.GOV | 45

Technical News

Accounting for Uncertainty in Travel Forecasting

Traditionally, travel forecasting models have been used to provide single-point predictions—that is, a single future scenario is 

developed, and the model is applied to that scenario. However, this 

approach ignores the deep uncertainty inherent in forecasting. This 

uncertainty comes from other uncertainties, including how systems 

work, how inputs to a system will change in the future, and which 

features of a system to focus on. Furthermore, emerging connected 

and autonomous vehicle technology, new mobility services, and 

changing travel patterns will potentially have significant unpredict

able impacts on future surface transportation operations and travel 

demand. To help address these uncertainties, the Federal Highway 

Administration published Uncertainty in Travel Forecasting: 

Exploratory Modeling and Analysis – TMIP-EMAT: A Desk Reference

(FHWA-HEP-21-032) in July 2021. This report demonstrates and 

motivates the use of travel forecasting models in an exploratory 

manner that accounts for the inherent uncertainties of the future.

-

This improved approach to travel forecasting is supported by a 

new planning and modeling tool: the Travel Model Improvement 

Program Exploratory Modeling and Analysis Tool (TMIP-EMAT). 

The TMIP-EMAT was developed to facilitate the use of explor

atory techniques with travel forecasting models and is one outcome 

of FHWA’s Exploratory Modeling and Simulation Study. This tool 

is available at 

-

https://tmip-emat.github.io/index.html.

The full report is available at www.fhwa.dot.gov/planning/tmip

/publications/other_reports/uncertainty_travel_forecasting/index.cfm.

Source: FHWA.

FHWA Releases Air Quality and Noise Analysis Tools

In 2021, the Federal Highway Administration developed the 

Database for Air Quality and Noise Analysis (DANA) tool. The 

DANA tool combines traffic data from existing data sources into 

a single database and processes the combined data into properly 

formatted inputs to the Environmental Protection Agency’s Motor 

Vehicle Emission Simulator model and FHWA’s Traffic Noise 

Model Aide (TNMAide). TNMAide—for use in the FHWA’s 

Traffic Noise Model (TNM)—is a spreadsheet tool that aids in the 

determination of the worst noise hour of the day, as required by 

23 CFR 772. TNMAide is also a method to estimate noise impacts 

by using hour by hour data.

DANA provides real-world measurements of traffic conditions 

for use in environmental analyses, replacing inputs from trans

portation models that only generate base-year traffic data. DANA 

helps ensure that environmental analyses use a consistent set of 

traffic data and processing methods across the entire country. 

FHWA provides the DANA tool as a resource to stakeholders. 

Use of the tool is voluntary and its use may not satisfy all regula

tory requirements.

-

-

The DANA tool, along with user guides and video training 

resources, is available on FHWA’s Air Quality website at 

http://www.fhwa.dot.gov/environment/air_quality/methodologies/dana

/index.cfm. TNMAide is available on FHWA’s Noise Website at: 

https://www.fhwa.dot.gov/environment/noise/traffic_noise_model/. For 

more information, contact DANAhelp@dot.gov or David Kall at 

David.Kall@dot.gov.

Policy and Legislations

USDOT Announces First Ever INFRA 

Extra Project Designations

The U.S. Department of Transportation recently designated 44 infrastructure projects around the country as Infrastructure for 

Rebuilding America (INFRA) Extra—a designation that makes 

project sponsors eligible to apply for credit assistance for up to 

49 percent of project costs. These projects made it to the final 

round for INFRA funding under the competitive grant program 

but were not awarded grants due to overwhelming demand and 

limited funds. Like the projects that received INFRA grants, the 

projects receiving the INFRA Extra designation will help rebuild 

the Nation’s infrastructure and create jobs.

The INFRA Extra initiative provides certain INFRA applicants 

the opportunity to apply for the Transportation Infrastructure 

Finance and Innovation Act (TIFIA) program, which provides 

Federal credit assistance for up to 49 percent of eligible project 

costs if the project advanced for funding but was not awarded 

INFRA grant due to resource constraints. This will potentially 

provide project sponsors with more funding than they would 

qualify for under a traditional TIFIA loan—which normally funds 

up to 33 percent of a project’s cost, subject to satisfaction of under

writing requirements.

-

This year, USDOT received a total of 157 eligible INFRA 

applications from 42 States, as well as Guam. And this year’s appli

cants collectively requested approximately $6.8 billion in grant 

funds—nearly seven times more than the $1 billion available for 

the program. The full list of INFRA Extra designated projects is 

available at 

-

www.transportation.gov/briefing-room/us-department

-transportation-announces-first-ever-infra-extra-project-designations.
46 | PUBLIC ROADS | WINTER 2022

INTERNET WATCH

An image from the Complete Streets website showing potential 

cross section improvements on a suburban arterial.

Source: FHWA.

by ANTHONY BOUTROS, JEFFREY SHAW, and PHILLIP BOBITZ

Complete Streets Website

The majority of States and hundreds of local jurisdictions across 

the country have adopted Complete Streets policies that strive to 

build streets that are safe, and feel safe, for all users. The Federal 

Highway Administration is focused on supporting transportation 

agencies to accelerate the implementation of a safe, connected, 

and equitable transportation network for travelers of all ages 

and abilities—particularly those from underserved communities 

facing historic disinvestment. Building Complete Streets combines 

innovations from multiple transportation disciplines to achieve 

safe, connected, and equitable street networks. The Complete 

Streets website serves as a portal to FHWA’s extensive resources 

and trainings, and also includes links to resources from other 

organizations to assist in planning, designing, and operating 

streets for the safety of all users. The site emphasizes resources for 

transforming project development through a Complete Streets 

implementation strategy for arterials and provides methods and 

measures of success for evaluating the outputs and outcomes of 

Complete Streets.

For more information, contact Anthony Boutros at 

anthony.boutros@dot.gov.

Focused Approach to Safety

Since 2004, the FHWA Office of Safety has used the Focused 

Approach to Safety (FAS) to identify areas of opportunity and to 

offer priority assistance to Focus States with the goal of reducing 

fatalities and serious injuries on the Nation’s highways. Periodically, 

the FAS is adjusted and updated based on current data and 

program evaluations. In October 2021, the FAS was updated 

again using the National Highway Traffic Safety Administration 

Fatality Analysis Reporting System, FHWA highway statistics, and 

U.S. Census data for a 6-year period covering 2014–2019. The 

update process confirmed the focus areas of roadway departure, 

intersections, pedestrians, and bicyclists, and rigorous data analysis 

and screening identified new Focus States. For more information, 

visit https://safety.fhwa.dot.gov/fas/, or contact Jeffrey Shaw at 

jeffrey.shaw@dot.gov or 202-738-7793.

Proven Safety Countermeasures Initiative Update

The FHWA Office of Safety recently introduced nine new 

countermeasures to the Proven Safety Countermeasures initiative 

(PSCi). These additions enhance the already diverse set of safety 

strategies for State, local, regional, and Tribal transportation 

professionals to consider implementing as part of their efforts to 

improve safety for all users on the Nation’s roadways. In addition 

to the 9 new countermeasures and crosscutting strategies, this 

most recent iteration of the PSCi updates the materials for the 

existing proven safety countermeasures to reflect the latest research, 

applications, and considerations for implementation. New website 

features, including a filter tool and search function, will help prac

titioners identify applicable countermeasures that meet their needs.

-

FHWA believes that widespread implementation of proven 

safety countermeasures, where appropriate, will accelerate the 

achievement of local, State, and national safety goals. The updated 

Proven Safety Countermeasures website is the one-stop shop for 

resources and information to advance the safety countermeasures 

in your jurisdiction.

For more information, visit https://safety.fhwa.dot.gov

/provencountermeasures/, or contact Phillip Bobitz at 

phillip.bobitz@dot.gov.

ANTHONY BOUTROS is a transportation specialist in FHWA’s Office of Safety.

JEFFREY SHAW is the Intersection Safety Program Manager in FHWA’s Office 

of Safety.

PHILLIP BOBITZ is a safety engineer in FHWA’s Office of Safety.

FHWA’s nine new proven safety countermeasures.

Source: FHWA.
WWW.FHWA.DOT.GOV | 47

TRAINING UPDATE

Utility managers coordinating transportation project efforts.

©Banana Oil / Shutterstock.com.

Source: FHWA.

Improve Construction Projects 

Through Utility Coordination

by JULIE JOHNSTON and SABRINA SYLVESTER

Utility coordination is critical to safely and efficiently completing any transportation project. If unexpected utility conflicts occur 

during highway construction projects, contractors can experience 

major hazards, which can then result in delays and increased 

project costs. In addition, insufficient utility information and 

poor management of utility conflicts can affect the success of 

these projects. Some common challenges include disruptions to 

construction sites, damage to installations, risk to the health and 

safety of the general public, and unnecessary utility relocation.

The Federal Highway Administration’s (FHWA’s) National 

Highway Institute (NHI) now offers two web-based trainings 

(WBTs) specifically to assist transportation managers who handle 

utility coordination, design, and relocation in construction 

projects. Participants will learn about utility agreement 

requirements, as well as how to identify and document existing 

utility facilities.

Achieving Success in Utility Coordination with NHI

NHI has developed two new courses in utility coordination for 

construction engineers, design project managers, highway 

designers, and utility coordinators and managers. The WBTs listed 

below will provide transportation professionals the knowledge and 

resources they need to more effectively coordinate utility functions.

Preparing and Communicating Effective Utility Relocation 

Requirements (FHWA-NHI-134117). The Preparing and 

Communicating Effective Utility Relocation Requirements course 

provides information about the purpose and value of utility 

agreements and their requirements. In this 3.5-hour WBT, 

participants will learn to differentiate between effective and 

ineffective supporting documents in utility agreements and 

statements, prepare and communicate these agreements, and 

evaluate the effectiveness of utility agreements and information in 

construction bid packages.

Utility Investigations (FHWA-NHI-134208). The Utility 

Investigations course provides attendees with a robust overview of 

practices and procedures for performing utility investigations 

during project delivery. In this 3.5-hour WBT, participants will 

learn the purpose of applying a risk-based approach to utility 

investigations, how to compare various utility investigation 

methods, how project delivery phases and utility investigation 

activities relate to each other, and how to identify typical utility 

investigation deliverables.

How to Attend or Host a Course

NHI invites professionals interested in earning continuing 

education units or professional development hours to visit 

http://bit.ly/NHIHome and browse the complete digital course 

catalog, which encompasses more than 400 courses spanning 

18 program areas. To sign up for alerts when a course session is 

scheduled, visit the individual course’s description page and click 

the “Sign Up for Session Alerts” link.

Interested hosts can submit a Host Request Form or find more 

information about hosting NHI courses by visiting http://bit.ly

/NHIHome.

NHI is an approved Accredited Provider by the International 

Association for Continuing Education and Training (IACET). As 

an IACET Accredited Provider, NHI offers continuing education 

units for its programs that qualify under the American National 

Standards Institute/IACET Standard.

JULIE JOHNSTON is the program manager for Utility, Railroad, and Value 

Engineering for FHWA.

SABRINA SYLVESTER is a contracted senior marketing specialist for 

FHWA’s NHI.
CARMASM Products Pioneer Cooperative 

Driving Automation Research

Cooperative driving automation (CDA) research is the key to creating a safer and more efficient transportation 

system. The CARMA product suite provides the necessary software to enable this research. 

All four products (CARMA CloudSM, CARMA PlatformSM, CARMA Streets, and CARMA Messenger) work together 

with V2X (Vehicle-to-Everything) Hub, a separate system that enables networked, wireless communications 

between automated vehicles, infrastructure devices, and personal communications devices. 

These tools are available online for collaboration and are currently being used in a set of research tracks 

examining the impact of CDA on traffic, reliability, and freight operations.

CARMA Cloud is a set of cloud-based, open-source software 

services enabling communication and cooperation between 

cloud services, vehicles, infrastructure, and road users. 

CARMA Platform is a vehicle-based platform that enables 

automated vehicles to interact and cooperate with road elements, 

such as other vehicles, infrastructure, and pedestrians.

CARMA Streets is an infrastructure-based system that allows automated 

vehicles to share information with other vehicles and infrastructure to 

enable cooperation and improve transportation operations and safety.

CARMA Messenger is a vehicle-based system for nonautomated vehicles, and enables their communication with 

other road entities to allow participation in the CDA network.

Download CARMA products at https://github.com/usdot-fhwa-stol.

Learn more at https://highways.dot.gov/research/operations/CARMA-products.
Are you a longtime transportation professional conducting 

new research on a particular topic? Or an industry 

freshman looking to expand your knowledge base?

The Federal Highway Administration (FHWA) 

has the online research tool that can help. 

Since 2006, “What’s New” in FHWA publications has been the online resource 

for fact sheets, TechBriefs, reports, and more. Each year, FHWA produces these 

comprehensive, up-to-date, and data-driven publications that can support your 

research needs. These publications cover a wide range of topics, including:

• Roadway safety and enhancements.

• Pedestrian and bicycle safety.

• Transportation equity.

• Connected and automated vehicles.

• Nondestructive evaluations.

• Bridge innovations, reconstruction, 

and rehabilitation.

• Pavement technology and materials.

• Intersection improvements 

and design.

• Intelligent transportation systems. 

To access the list of downloadable research documents, visit 

www.fhwa.dot.gov/publications/lists/whatsnew/index.cfm.

Photo illustration by FHWA. Highway image: © kanvag / AdobeStock.com. 

Vehicle image: © lunamarina / AdobeStock.com. Book image: © Photocreo Bednarek/ AdobeStock.com.
U.S. Department 

of Transportation

Federal Highway 

Administration

Attn: HRTM

 1200 New Jersey Avenue, SE 

Washington, DC 20590

Official Business

Penalty for Private Use $300

FHWA-HRT-22-002

HRTM-20/1-22(2M)E