ROSWELL, Ga. — The city of Roswell is installing emergency vehicle preemption technology at all 107 of its traffic lights.

Instead of the standard red-yellow-green sequence, the Hawk signal has added some new variations.

Knox County traffic engineers Grady Owen and Alan Childers use technology to optimize local traffic signals and improve road safety and efficiency. Here's how.

According to a Facebook post from the City of Puyallup, crews will be installing a new signal at the Safeway entrance from 7 a.m. to 5 p.m. on July 19.