New Hampshire Code of Administrative Rules
Fis - Executive Director, Fish and Game Department
Chapter Fis 1500 - OFF HIGHWAY RECREATION VEHICLES AND SNOWMOBILES
Part Fis 1511 - SOUND LEVELS OF OHRV's
Section Fis 1511.03 - Sound Level Limits for Stationary ATVs, UTVs, Trail Bikes, and any other OHRV

(a) No ATV, trail bike, UTV, or any other OHRV shall be manufactured, sold, offered for sale, or operated in this state which produces a sound level of more than 96 decibels of A sound pressure when measured in accordance with the Society of Automotive Engineers (SAE) J1287-201704 standard available as described in Appendix A attached hereto.

(b) No ATV, trail bike, UTV, or any other OHRV shall be manufactured, sold, offered for sale, or operated in this state unless it is equipped with a muffler in good working order and with a functioning spark arrester of a type approved by the U.S. Forest Service. This paragraph shall not apply to any OHRV that is operated exclusively by means of an electric motor.

(c) No person shall operate an ATV, trail bike, UTV, or any other OHRV in this state that is equipped with a muffler cut out, by pass switch or similar device that serves to prevent exhaust gases from being received by the installed muffler.

(d) The operator or owner of any ATV, UTV, trail bike, or any other OHRV shall, when requested by any law enforcement officer, submit his or her vehicle to a sound test conducted pursuant to Fis 1511.04.

(e) The provisions of paragraphs (a), (b), (c), (d), and (e) shall not apply to ATV's, UTV's, trail bikes, or any other OHRV operated at permitted OHRV events as defined in Fis 1501.01(d).