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Emergency Vehicle Alerts Boost Driver Awareness

Every day, police, fire, emergency medical services (EMS), transportation, and towing professionals are working on or near the Nation’s roadways, clearing roadway incidents and helping ensure the safe and efficient flow of traffic. Their familiar amber, blue, and red emergency lights are meant to alert drivers to their presence and cue them to use greater caution. New technologies promoted by Every Day Counts round six (EDC-6) Next-Generation Traffic Incident Management (NextGen TIM) are helping boost driver awareness even more.

Motorist alert systems work to inform drivers of first responder activity on roadways where they travel. The underlying premise is that alerting motorists to downstream traffic incidents sooner may increase compliance with State move over laws, allowing for more time to safely change lanes and/or slow down. Timely awareness of incident activity ahead can increase driver attentiveness and responsiveness, making safer conditions for responders and other road users.

Motorist alert systems, also referred to as digital alert systems or responder-to-vehicle alerts, rely on Global Positioning System (GPS) technology that knows the responder’s location. This can be accomplished with a small transponder specifically for this purpose, separate vehicle location systems, or by connecting with vehicle manufacturer systems. Roadway maintenance vehicles, responder vehicles, and temporary traffic control devices are geolocated and shared with drivers. Motorist alerts are one of several technologies being promoted as part of EDC-6 NextGen TIM.

A digital alert can be set up to activate anytime an equipped traffic control device is deployed, or when a response or maintenance vehicle’s emergency lights are activated. Passive activation helps ensure response personnel are not burdened with additional actions. Conversely, vehicles can also be set up to selectively not participate in an alert, which is sometimes necessary for covert law enforcement activities.

Emergency vehicle alerts shown on car dashboard

Emergency vehicle alerts advise motorists of the presence of roadside responders.

Credit: Enforcement Engineering, Inc.

Motorists receive alerts through traveler information systems, navigation providers, smartphone apps, or a connected vehicle on-board unit. When an activation occurs, work zone and traffic incident data are pushed to third-party navigation providers like Waze®, Google®, TomTom®, and Apple®.

Transportation agencies and the digital alert industry are also working with automakers to deliver these alerts directly to cars as part of vehicle-to-vehicle communications. FHWA developed the CARMASM program to fully explore cooperative driving automation (CDA), where vehicles communicate with each other, the infrastructure, and other road users. CDA concepts that support responder safety and traffic incident management are part of the CARMASM effort.

Pennsylvania Reduces Roadside Vehicle Crashes

Many public safety, transportation, and private sector agencies are using motorist alerts to improve situational awareness among drivers. The Pennsylvania Turnpike Commission has equipped 158 maintenance and service patrol vehicles with the ability to broadcast emergency alerts. When the service vehicle activates its amber emergency warning lights, a signal is sent to a mapping provider (Waze®), which pushes an alert to subscribers in the vicinity.

According to Pennsylvania Turnpike Commission TIM Coordinator Todd Leiss, crashes involving roadside agency vehicles were reduced from 30 in 2018 to zero in 2020. He attributes much of the credit for that reduction to emergency vehicle alerts.

Similarly, around the country, private companies such as towing operators are realizing the safety impacts and are installing equipment on tow trucks to help warn drivers of the trucks’ roadside presence. This is important because towing companies frequently act as single responders to disabled vehicles, often without the knowledge or support of other agencies like law enforcement or transportation. Emergency alert technology can be used on any incident response vehicle, including police, fire, EMS, transportation, towing, and others.

Smartphone app showing slow down alert

A smartphone app displays a “Slow Down, Move Over” alert.

Credit: Pennsylvania Turnpike Commission

Vehicle telematics and summary dashboards are sometimes part of the alert system deployment, helping to tabulate and visualize the number of deployments, duration of stops, and the number of motorists potentially warned. In addition, since responder vehicle location is an important part of the technology, some agencies are able to use the dashboards for better resource management.

Leiss estimates that in just over 1.5 years, the system has alerted 2.8 million Waze® users to Pennsylvania Turnpike incidents.

“Aware drivers are potentially safer drivers when passing roadway incidents, work zones, and responders,” said EDC-6 NextGen TIM Co-Leader Paul Jodoin, “Next-generation TIM technology like digital alerts is proving to be a great way to help create better awareness among road users.”

EDC Outtakes: NextGen TIM

EDC’s Next-Generation TIM promotes new technologies to help local agencies better manage incidents. In this EDC Outtake, Texas Department of Transportation TIM Coordinator David McDonald talks about his experience incorporating TIM while working for the city of Austin.


View the “Talking TIM” webinar series for examples of how agencies apply strategies to improve TIM programs.

Contact Paul Jodoin or Jim Austrich of the FHWA Office of Operations for NextGen TIM information, technical assistance, and training, including workshops and peer exchanges.

Notice: The U.S. Government does not endorse products or manufacturers. Trademarks or manufacturers’ names appear in this article only because they are considered essential to the objective of the document.

Recommended Citation: U.S. Department of Transportation, Federal Highway Administration - Washington, DC (2021) Innovator Newsletter, January/February 2022, Volume 15 (88). https://doi.org/10.21949/1521806