Two Bronx City Councilmen take opposite views on recently passed legislation that limits how long vehicles can remain stopped with their engines running.

Riverdale and Kingsbridge lawmaker Oliver Koppell introduced a bill that requires ambulances to use “idle reduction technology” that will provide heat or air conditioning for the vehicles without running the engine. Ambulances parked on side streets, engines running, are a common sight citywide.

And Mr. Koppell cosponsored another bill that limits the time vehicles can idle around schools, reducing it from three minutes to one minute.

“The reduction of diesel exhaust is critical for New York City,” Mr. Koppell said in a press release. “Idling engines are dangerous to public health, exacerbating asthma and respiratory disease, particularly in children, and contributing to global warming.”

But City Councilman Jimmy Vacca, of the East Bronx, zeroed in on the consequence of this increased enforcement: more frequent fines. Police officers and officials from the departments of parks, sanitation and environmental protection would be able to issue fines, Mr. Vacca pointed out in a press release.

“Who will be giving tickets in my neighborhood next — the Landmarks Preservation Commission?” he asked.