ORLANDO, Fla. -- An Orange County elementary school was part of a push to cut exhaust pollution by creating idle-free zones for parents waiting to pick up their children.

Students with orange vests went car-to-car outside of Shenandoah Elementary Thursday asking parents not to leave their cars running while waiting in line.

Commissioner Linda Stewart said parents who keep engines running while sitting in pickup zones are endangering children.

"The children breathe 50 percent more particles than an adult and the impact to their health in the long run is asthma that you see a lot of in the hospitals," Stewart said. "I think parents don't realize the impact of leaving their cars idling for long periods of time and the effects it is having on young children."

The top source of air pollution in Central Florida is exhaust from vehicles, Local 6 reported.

In fact, for every hour a car sits idle, it releases nearly four pounds of carbon dioxide into the atmosphere, Local 6 reported.

Watch Local 6 News for more on this story.