SAFE SYSTEM PRINCIPLES

Zero is our goal. A Safe System

is how we will get there.

Death/Serious Injury

is Unacceptable

Humans

Make Mistakes

Humans Are

Vulnerable

Safety is

Proactive

Redundancy

is Crucial

Responsibility

is Shared

While no crashes are desirable, the 

Safe System approach prioritizes 

crashes that result in death and 

serious injuries, since no one should 

experience either when using the 

transportation system.

People will inevitably make mistakes 

that can lead to crashes, but the 

transportation system can be designed 

and operated to accommodate human 

mistakes and injury tolerances and 

avoid death and serious injuries.

People have limits for tolerating crash 

forces before death and serious injury 

occurs; therefore, it is critical to 

design and operate a transportation 

system that is human-centric and 

accommodates human vulnerabilities.

All stakeholders (transportation 

system users and managers, 

vehicle manufacturers, etc.) must 

ensure that crashes don’t lead to 

fatal or serious injuries.

Reducing risks requires that all 

parts of the transportation system 

are strengthened, so that if one 

part fails, the other parts still 

protect people.

Proactive tools should be used to 

identify and mitigate latent risks in 

the transportation system, rather 

than waiting for crashes to occur 

and reacting afterwards.

FHWA-SA-20-015

APPROACH

SAFE

SYSTEM

Imagine a world where nobody has to die from 

vehicle crashes. The Safe System approach aims to 

eliminate fatal & serious injuries for all road users. It 

does so through a holistic view of the road system that 

first anticipates human mistakes and second keeps 

impact energy on the human body at tolerable levels. 

Safety is an ethical imperative of the designers and owners 

of the transportation system. Here’s what you need to know

to bring the Safe System approach to your community.

THE

Safe

Speeds

R

E

D

U

NDANCY IS CRUCIAL

SAFETY IS PROACTIVE

RESPONSIBILITY IS SHARED

HUMANS ARE VULNERABLE

HUMANS MAKE

MISTAKE

S

DEATH/SERIOUS INJURY IS UNACCEPTABLE

Safe

Vehicles

Post-Crash

Care

Safe Road

Users

Safe

Roads

THE

SAFE SYSTEM

APPROACH
W

YO

HERE ARE

ON

THE

SAFE S

U

YSTEM

JOURNEY?

Implementing the Safe System approach is our shared responsibility, 

and we all have a role. It requires shifting how we think about 

transportation safety and how we prioritize our transportation 

investments. Consider applying a Safe System lens to upcoming 

projects and plans in your community: put safety at the forefront and 

design to accommodate human mistakes and injury tolerances. Visit 

safety.fhwa.dot.gov/zerodeaths to learn more.

Making a commitment to zero deaths means addressing every aspect of crash risks through the five 

elements of a Safe System, shown below. These layers of protection and shared responsibility promote a holistic 

approach to safety across the entire transportation system. The key focus of the Safe System approach is to 

reduce death and serious injuries through design that accommodates human mistakes and injury tolerances.

The Safe System 

approach addresses 

the safety of all road 

users, including 

those who walk, 

bike, drive, ride 

transit, and travel by 

other modes. 

Vehicles are 

designed and 

regulated to 

minimize the 

occurrence and 

severity of collisions 

using safety 

measures that 

incorporate the 

latest technology.

Humans are unlikely 

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.

Designing to 

accommodate human 

mistakes and injury 

tolerances can greatly 

reduce the severity of 

crashes that do occur. 

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.

When a person is 

injured in a collision, 

they rely on 

emergency first 

responders to quickly 

locate them, stabilize 

their injury, and 

transport them to 

medical facilities. 

Post-crash care also 

includes forensic 

analysis at the crash 

site, traffic incident 

management, and 

other activities.

Safe Road

Users

Safe

Vehicles

Safe

Speeds

Safe

Roads 

Post-Crash

Care 

THE SAFE SYSTEM APPROACH VS. TRADITIONAL ROAD SAFETY PRACTICES

Traditional

Prevent crashes

Safe System

Prevent deaths and serious injuries

Improve human behavior Design for human mistakes/limitations

Control speeding Reduce system kinetic energy

Individuals are responsible Share responsibility

React based on crash history Proactively identify and address risks

Whereas traditional road safety 

strives to modify human behavior 

and prevent all crashes, the Safe 

System approach also refocuses 

transportation system design and 

operation on anticipating human 

mistakes and lessening impact 

forces to reduce crash severity 

and save lives.

SAFE SYSTEM ELEMENTS