Anyone who notices a vehicle emitting heavy smoke from the tailpipe for 10 seconds or longer can file a report over the phone or online with the Texas Commission on Environmental Quality.

The reporting system is not an enforcement program. But drivers are informed by mail that they can be ticketed and fined for operating a smoking vehicle. Violators can be fined up to $350 for the first offense, according to state law. Fines increase up to $1,000 for each additional offense.

Observers can file reports by calling 800-453-7664 or by visiting www.tceq.texas.gov.

North Texas residents can also file reports with the North Central Texas Council of Governments by calling 817-704-2522 or by visiting www.nctcog.org.