ODOT replacing 'Prepare To Stop When Flashing' signs with new tech

JACKSONTOWN - The recent removal of "Prepare To Stop When Flashing" signs from two locations along State Route 16 in Licking County has prompted a lot of questions from the public.

The changes were made because the signs and systems have reached the end of their lifespan. We have replaced them with a more advanced, radar-based system that has been proven to reduce crashes at hundreds of intersections across the state.

From 2019 - 2023, the intersection at SR 16 and Licking Valley Road saw 37 crashes with 14% of them resulting in injuries. All but seven of the crashes were rear-end crashes. Three of the crashes involved a motorist running a red light and six involve drivers turning left.

At the SR 16 and Marne Road intersection, there have been 21 crashes with 38% of them resulting in injuries. Fifteen of the crashes were rear-end crashes and 6 involved running a red-light.

What has changed?
The Ohio Department of Transportation has updated our traffic control systems as part of our ongoing commitment to improve road safety.

For more than a decade, we have been replacing older "Prepare to Stop When Flashing" (PTSWF) signs with radar-based detection systems. These new radar units, installed at nearly every ODOT-maintained intersection, monitor vehicles from up to 900 feet away, detecting their speed and distance to make intersections safer.

The detectors looked for breaks or gaps in traffic where it would be safer to turn the signal from green, to yellow, then to red. This is not always possible under heavy traffic conditions because sometimes there is not a gap and the green phase "maxes out", which means the signal tried to find a gap, but none was present, and it had reached the maximum amount of green time for that approach.

The old system did not do this.

Why did we make the change?
Studies have shown that when the PTSWF lights were activated, instead of slowing down drivers frequently sped up. This lead to more high-speed, severe crashes. The new system aims to decrease red-light running crashes, and it has proven to be successful. When we look at locations in Ohio that have been switched from PTSWF signs to the new radar-based system, we have seen:

• 23% fewer total crashes
• 35% fewer serious crashes
• 42% fewer angle crashes
  • 83% decrease in angle crashes with injuries
• 50% fewer red-light running crashes
• 50% fewer rear-end crashes with injuries

These systems are not new to ODOT. In 2012, it was placed in service at two locations on US 33 in Fairfield County: the Pickerington Road and Sharp Road intersections. Both locations showed a notable decrease in crashes in just one year.

A more recent study was conducted in 2024 at SR 32 & Dela Palma Road in Clermont County where PTSWF signs were removed, and radar detection was added.

For comparison, this intersection serves an average of 26,475 vehicles a day while the SR 16 & Marne Road in Licking County serves 26,417 vehicles a day. Both are four-lane, divided roadways with a 60-mph approach. SR 32 saw a 39% reduction in total crashes and a 55% reduction in injury crashes after the implementation of the radar-based system and the removal of the PTSWF signage.

Learn more about this smart technology by watching this video: SmartSensor Advance (youtube.com)

Our Commitment to Safety
ODOT is constantly looking for engineering solutions to make our roadways safer and reduce the risk of crashes, especially those resulting in serious injuries or deaths. Our mission is to provide a transportation system that is safe, accessible, well-maintained, and positioned for the future.

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