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Safe System Approach

Imagine a world where nobody has to die from vehicle crashes.

At MDOT, zero deaths and serious injuries is our goal and safety is paramount. Every day we strive to improve the overall safety for all road users. Unfortunately, despite our safety efforts, Michigan's road fatalities and serious injuries continue to rise. That is why we have implemented a lifesaving concept called the Safe System Approach.

Zero is our goal. A Safe System is how we will get there.

Learn more about this approach and how you can be part of the safe solution.

FHWA's Safe System Approach (SSA) logo showing the SSA principles and elements.

What is the Safe System Approach? Video

What is the Safe System Approach?

The Safe System Approach (SSA) is a human-centered, holistic approach that aims to eliminate fatal and serious injuries for all road users. It seeks safety through vehicle and road design, as well as operational changes, rather than relying on behavioral changes. The focus is on all road users. SSA anticipates human mistakes, and through a redundant system, strives to minimize the impact on the human body if a crash does occur. It is the tool that MDOT will use as we work toward achieving our goal of Toward Zero Deaths on Michigan roads.

Safe System Principles

Prioritize crashes that result in death and serious injuries, since these should not be a consequence of mobility.

People will make mistakes that can lead to crashes, but the transportation system can be designed and operated to accommodate human mistakes and injury tolerances.

Human bodies have limits for tolerating crash forces before death and serious injury occur. It's critical that transportation systems accommodate human vulnerabilities.

Government agencies, industry, advocacy groups, researchers, and the general public all have a role in ensuring that crashes don’t lead to fatal or serious injuries.

Proactive tools should be used to identify and address safety issues and risks, rather than waiting for crashes to occur and reacting after the fact. 

Redundancy is essential in reducing risk, preventing death or injuries, and ensures that if one part fails, the other parts are there to protect people.


Making a commitment to zero deaths and reducing injuries on Michigan roads means addressing every aspect of crash risk. It means sharing the responsibility of a crash between the five elements of a Safe System. This redundant system is essential because those five elements are not sufficient to protect the road user on their own.

Safe road users are expected to follow the rules of the road. They should obey traffic laws, make safe choices, and wear seatbelts while in a vehicle. Road design, education, enforcement, and vehicle feedback are also important in assisting and encouraging users to behave safely.

Safe vehicles not only protect the driver, but also protect all road users. Vehicles have active safety measures, such as blind spot detection, emergency braking, and lane keep assist, to help prevent crashes. Passive safety measures, such as seatbelts and airbags, help to prevent serious injuries in the event of a crash. The vehicle owner is responsible for making sure the vehicle is in working order, tires have good treads, and vehicle recalls have been fixed.

Safe speeds mean driving the posted speed limit or at speeds safe for road conditions. There are times motorists should slow down, such as congestion, adverse weather conditions, or poor visibility. Safe speeds help the motorist to avoid crashes and mitigate the severity by reducing the speed at impact.

Safe roads take driver behavior into account when designing the road. Design features and countermeasures can separate users in space and time, as well as anticipate human mistakes and help mitigate the effects if a crash occurred. There are many design features that assist the road user, but some examples include cable median barrier that prevents vehicles from crossing into oncoming traffic, roundabouts that reduce congestion and increase safety for vulnerable road users by slowing traffic, bike lanes and sidewalks to separate vulnerable road users, and lighting that benefits all road users.  

Post-crash care incorporates all elements related to emergency services, medical care, crash reporting and investigation, traffic incident management, and the justice system. Aspects of post-crash care include providing shorter response times, improving access to trauma hospitals, increasing and improving training to provide accurate crash reporting, and alerting motorists that there is congestion due to a crash or to avoid an area.

Safe System Approach & Toward Zero Deaths

Some people may ask what the different is between Safe System Approach (SSA) and Toward Zero Deaths (TZD)? TZD is a statewide campaign that focuses on creating a culture of safety and SSA is the tool used to achieve the zero deaths vision. This approach believes that death and serious injury are unacceptable, humans make mistakes and are vulnerable, the responsibility of a crash is shared, safety is proactive, and redundancy is crucial. TZD and SSA work together - one cannot exist without the other. A Safe System needs to be in place if we are to achieve zero deaths and serious injuries, and SSA requires a culture that places safety first when making road system investment decisions.