Improving traffic safety for vulnerable road users: Safe System Approach

​​Thank you for the invitation and the kind introduction.

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I am honored to be invited to speak to you. I do have more than a few years under my belt in transportation. However, most of my direct experience is in aviation. Since joining the NTSB in early 2020, I have devoted much of my attention to traffic safety.

By now, I suspect the Safe System Approach to Traffic Safety isn’t a new concept to most of you. Just this morning, the opening session of this conference included a discussion on the urgency to create a Safe System for Texas Roadways. In addition, the U.S. DOT has adopted the Safe System Approach as the guiding paradigm to address roadway safety, and the Safe System Approach is now prominently featured in the National Roadway Safety Strategy.

Today, I will offer a very brief introduction to the Safe System Approach, and I’ll explain why the Safe System Approach is on the NTSB’s Most Wanted List of Transportation Safety Improvements–especially as it relates to vulnerable road users.


Let me start by telling you a little more about NTSB. The National Transportation Safety Board is an independent federal agency charged with investigating accidents in all modes of transportation and issuing safety recommendations for the purpose of preventing similar accidents in the future.

We are best known for our accident investigations. But the NTSB also researches and prepares special studies concerning transportation safety, and we help to coordinate the resources of the federal government and other organizations to provide assistance to victims and their family members impacted by major transportation disasters.

We are an agency with about 400 full time employees, led by five board members who are nominated by the President and confirmed by the Senate. Currently, we have one vacancy on the Board. And, as you may know, my colleague the Honorable Jennifer Homendy was sworn in as our 15th Chair last August.

We at NTSB have a history of participating in this conference. We value our collaborative relationship with state and local stakeholders in the effort to improve transportation safety.


In April of last year, the NTSB adopted the 2021-2022 Most Wanted List of Transportation Safety Improvements. The Most Wanted List is our most important advocacy tool.

Again, the NTSB works on all modes of transportation. There were almost 41,000 fatalities [40,876] in all U.S. transportation in 2020. However, as you know, the vast majority of transportation fatalities occur on our roadways.

The pie chart (on the left) shows that about 95% of transportation deaths occurred on roads, while fatalities in the other four primary modes, together, comprised 5%.

The bar chart (on the right) breaks down 2020 highway fatalities according to various categories. While the majority of these roadway deaths were among vehicle occupants, vulnerable road users such as pedestrians, motorcyclists, and bicyclists comprise a large number. In fact, more than one-third of traffic deaths were vulnerable road users.

Some folks believe the safety items included on our Most Wanted List are determined entirely by the number of fatalities. If that were the case, the Most Wanted List would focus exclusively on highway safety — because of the staggering number of highway deaths.

But that is not the case. In fact, we use a methodology that looks at multiple factors when developing our Most Wanted List. Of course, the number of fatalities and serious injuries is very important. However, we also seek to identify other transportation challenges where we at NTSB can leverage our unique expertise and capabilities to advance safety and press for improved safety practices, regulations, and policies in various priority areas.


Why do we need a Safe System Approach to traffic safety?

This chart shows motor vehicle crash deaths from 1975 to 2021. The highest number of deaths occurred in 1979 when over 51 thousand people died on US roadways. The fewest deaths occurred in 2014, when 32,744 died in roadway crashes. From 1979 to 2014, there was a 36% decline. This chart also shows some periods of sharp decline—most notably in the early 1980s, early 1990s, and late 2000s. These periods coincided with US economic downturns.

In 2020, despite a substantial decline in traffic activity due to the global pandemic, motor vehicle crash deaths increased by 8 percent to almost 39,000 deaths. Further, NHTSA projects the final data will show that road deaths increased an additional 11% in 2021 to almost 43,000. That’s a staggering figure we have not seen since 2005.

Focusing on the period from 2014 to 2021, traffic fatalities increased by 31%. 


This chart shows US traffic deaths among vulnerable road users, including pedestrians, bicyclists, and motorcyclists. Looking at the same 2014-2021 period, we see a jump from 9,935 to a projected 14,429 vulnerable road user deaths, a 45% increase. If we only consider pedestrians and bicyclists (that is, the bottom segments of each bar), we see a 48% increase. Keep in mind that total traffic fatalities increased by 31% during the same 8-year period. Therefore, disproportionately, increasing numbers of vulnerable road users, especially pedestrians and bicyclists, are being killed on our roadways.

So, while we might have started with a vision of reaching Zero in the US, we need to look at a new approach to roadway safety. I submit that, if the vision is ZERO, the way to get there is a Safe System Approach.


As I mentioned earlier, the number of fatalities is one of many factors that we considered when putting together the Most Wanted List. There are 10 items across all modes of transportation on our Most Wanted List.

There are five highway safety improvement items, and I will return to them shortly.

In aviation, we advocate for effective Safety Management Systems in all revenue passenger-carrying operations. We also encourage installation of crash-resistant recorders and the establishment of flight data monitoring programs to capture the data which is key to improving aviation safety.

In marine, the NTSB wants to see improvements in passenger and fishing vessel safety. We also want to see improvement in pipeline leak detection and mitigation.

Finally, in rail safety, we are advocating for the improvement of rail worker safety.


Now, let me return to the five Most Wanted Highway Safety Improvement Items. These items focus on speeding, distracted driving, drug and alcohol impairment, improved collision-avoidance and connected-vehicle technologies, and protecting vulnerable road users through a Safe System Approach to traffic safety.

I understand there are six emphasis areas in the Texas Strategic Highway Safety Plan, four of which directly correspond with our Most Wanted List – that is, distracted driving, pedestrian safety, impaired driving, and speeding.


Now let’s talk specifically about the Safe System Approach.

To understand the Safe System Approach, it is useful to look at how it differs from the traditional approach. Traditionally, we focus on preventing crashes by changing individual human behavior, so we attempt to convert all of us into perfect drivers, perfect pedestrians, and perfect bicyclists. We try to mitigate injury severity by increasing occupant protection and improving crashworthiness. And we tend to put roadway safety in the hands of each individual road user.

I’ll note that these are all important tools, and implementing them certainly helps. For example, vehicles are safer, and we have seen a significant decline in motor vehicle occupant deaths over decades.

But as you saw earlier, the overall trend is not downward, and definitely not for pedestrians and bicyclists. The trend calls for a change.


In a Safe System Approach, the focus is on injury severity. From the outset, we seek to eliminate death and serious injury with an understanding there may be some crashes with less severity. We no longer try to turn all of us into perfect drivers, pedestrians, and bicyclists. It is assumed that we all make mistakes. The emphasis is on methods to prevent these mistakes from causing deaths or serious injuries. Human vulnerabilities are accommodated by managing kinetic energy through engineering, design, and policy. We also acknowledge that road safety is a shared responsibility among road users, designers, planners, engineers, corporations, and policy makers.


These are key concepts. The top four boxes are principles that were discussed in connection with the last slide. Here, I want to talk about three additional principles. 

First, safety is proactive. Instead of fixing problems after a fatal or serious injury crash has occurred, we try to predict these crashes. Second, using the “Swiss cheese” model in safety, we know that redundancy is crucial. So there should be multiple layers of safety. And, finally, in the event a crash occurs, we must identify and understand all the key risk factors.


While this is a change from the traditional approach to traffic safety, many tools already exist. For those that do not yet exist, we should seek to accelerate their development.

In 2018, the Road To Zero Coalition, led by NSC with the support of three US DOT agencies—NHTSA, Federal Highway, and FMCSA— commissioned the Rand Corporation to identify three main strategies. These involve doubling down on what works, accelerating advanced technology, and prioritizing safety. I will provide some examples of the first two shortly. For prioritizing safety, the key concept is that safety should not be a tradeoff in a cost-benefit analysis. Safety should be desired and prioritized. This requires a strong safety culture at all levels.


The Safe System Approach focuses on these five elements. Here’s how it works.

With a strong safety culture at every level, from individuals to the federal government, we can address the safety needs of all road users, not just drivers. We understand that road users will make mistakes, so we double down on what works – such as well-designed and properly worn seat belts for all seating positions. We also promote greater use of vehicle technologies that already exist, such as automatic emergency braking and lane departure technology. We should accelerate development and adoption of additional advanced driver assistance systems.

We know there are road designs that can create a safer environment for vulnerable road users – for example, separated bike lanes and separate traffic signal timing for pedestrians and motor vehicles. Because we know that injury severity is tied to kinetic energy, which is proportional to speed, we need to rethink speed management. Our roadways are overdesigned to accommodate mobility, not safety. It is crucial to move forward using roadway design to better manage drivers’ safe speed and to rethink how speed limits are set.

Many of these tools are already here, and the NTSB has offered numerous safety recommendations which will reinforce the Safe System Approach. Further, we must implement proven behavioral measures such as education and enforcement. The important tools available to us should be used together in an integrated fashion to promote a broad Safe System Approach.


While we at NTSB are known for investigations, we also have a mandate to conduct safety studies. We have a long history of advocating for vulnerable road users. This slide takes you down a memory lane. As far back as the early 1970s, shortly after the agency was established, we worked on two special studies on pedestrian and bicyclist safety. 


Fast forward to the last few years, we published five reports addressing various safety issues that are crucial to vulnerable road users. I encourage you to look at these reports and their associated safety recommendations. Many of them fit into the Safe System Approach to traffic safety, especially for vulnerable road users.


In May of 2021, I had the privilege of kicking off the NTSB emphasis on the Safe System Approach by hosting a virtual roundtable. Subsequently, Chair Homendy hosted an additional six roundtables, with each addressing a specific element. All seven events are posted on our YouTube channel.


Former NTSB Vice Chair and Board Member Bella Dinh-Zarr participated in this conference a few years ago. Last Thursday, I had the privilege of hosting her and other experts in a roundtable discussion of a featured Most Wanted List safety recommendation intended to help prevent alcohol-impaired driving. As we’ve discussed here today, a Safe System Approach requires multiple tools. And in the area of impaired driving, one of those tools is lowering the legal BAC limit from .08 to .05. Our recent roundtable focused exclusively on the challenges associated with implementing a .05 standard. The session was recorded, and you can find it posted on the NTSB YouTube channel.

In the fall, we will host Part Two of our .05 roundtable series, and we’ll discuss state legislative initiatives. That session will likewise be recorded and posted on our YouTube channel.


The NTSB remains committed to eliminating highway deaths for all road users by utilizing a Safe System Approach. We enjoy working with our partners and members of the safety community. Do not hesitate to reach out to us if we can help those of you here in Texas who are striving to achieve our common goal of Zero Traffic Deaths.

Please connect with us at NTSB via our various social media channels. Or you can contact my senior advisor, Ivan Cheung, or our safety advocate for this issue, Leah Walton.

That concludes my remarks. Again, my thanks for the opportunity to share our views on this important topic.

SLIDE 18 – End Slide