R.I. Gen. Laws § 31-16.1-3: Restrictions on idling for diesel engines.

No person shall on or after July 1, 2007, cause, allow or permit the unnecessary operation of the diesel engine vehicle while said vehicle is stopped for a period of time in excess of five (5) consecutive minutes in any sixty (60) minute period unless exempted pursuant to regulations adopted by the department of environmental management. Failure to operate the diesel engine vehicle in conformity with the rules of the department of environmental management adopted pursuant to § 23-23-20.2 shall constitute a violation of this chapter.