Regulations limiting school bus idling to no more than five consecutive minutes are now enforceable in Allegheny County.

The regulations were enacted by County Council to protect schoolchildren from the harmful effects of school bus diesel exhaust, which contains toxic gases and soot that can pose a significant health risk.

Exemptions to the idling law are allowed in hot or cold weather, in maintenance and emergency situations and in traffic conditions beyond the control of the driver. The regulations prohibit drivers from parking or idling a school bus within 100 feet of a school's air intake system unless there are no alternative areas to park or stop.

The public may report suspected violations to the Allegheny County Health Department at 412-687-2243.