Rhode Island requires biennial emissions inspections to be conducted in conjunction with safety inspections.
Diesel Vehicles:
Diesel vehicles with a GVWR of 8500lbs or less are required to be tested for Safety and Emissions. Heavy duty diesel powered vehicles (weighing over 8500 pounds) must be inspected annually at an "A" Class inspection station.
Exemptions:
1. New vehicles for first (2) model years or 24,000 miles, whichever comes first
2. Vehicles registered as antiques
3. Motor vehicles 25 years old or older must undergo inspection for safety and emissions, but are not failed if they do not pass emissions standards
4. Vehicles manufactured as kit cars may receive an alternate type of inspection.
For more information visit: https://www.riinspection.org/
Rhode Island General Laws
§ 31-23-13. Muffler
Every motor vehicle shall at all times be equipped with a muffler in good working order and in constant operation to prevent excessive or unusual noise and annoying smoke. No person shall use a muffler cutout, bypass, or similar device upon a motor vehicle on a highway. Any exhaust system shall be deemed defective if any changes, modifications, alterations, deletions, or adjustments have been made which would cause the exhaust system to generate a higher or louder sound level than would be generated by the exhaust system customarily installed by the manufacturer as original equipment. The defective exhaust system shall be replaced or repaired to restore the exhaust system to the performance specifications of the original equipment. Failure to replace or restore the exhaust system as required in this section within five (5) days shall be deemed a civil violation and violators are subject to fines enumerated in § 31-41.1-4.
§ 31-45-1. Noise limits
(a) No person shall operate a motor vehicle, nor shall the owner of any vehicle allow the vehicle to be operated, at any time, or under any condition of grade, load, acceleration, or deceleration, in such a manner as to exceed the following noise limit based on a distance of fifty feet (50′) from the center of the lane of travel within the speed limit. For the purposes of this section, "dbA" means decibels measured with a calibrated sound level meter weighted to the "A" scale.
(b) In speed zones of thirty-five miles per hour (35 mph) or less, not more than eighty-six (86) dbA. In speed zones of more than thirty-five miles per hour (35 mph), not more than ninety (90) dbA.
(c) Violations of this section are subject to fines enumerated in § 31-41.1-4.
