Hudson, NH Noise Ordinances: Vehicle Noise (2026)

Both rules sit in § 249-4J, the "prohibited noise-generating activities" list inside Hudson's Noise chapter (Ch. 249, adopted 1989 by Ord. No. O88-6). The first item bars sounding a motor vehicle horn or other audible signal device "at any time unreasonably," carving out authorized emergency vehicles and any honk that's genuinely needed to prevent or avoid an accident; casual or harassing honking away from an emergency isn't protected. The third item addresses exhaust noise: no person may discharge into the air the blow-down of a steam vent or the exhaust of a stationary internal-combustion engine or air compressor unless the discharge passes through a muffler, and that muffler has to keep the resulting sound within the limits set by Noise Limit 2 in § 249-4B.

Those limits are the same continuous-sound-level table used elsewhere in the chapter: a residential or institutional receptor caps out at 55 dBA in daytime hours and 50 dBA at night, business and recreational receptors at 65/55, and industrial receptors at 75/75. So an unmuffled or defective exhaust that pushes noise past those numbers at a nearby receptor violates the section even without a separate horn complaint. The chapter's MUFFLER definition in § 249-2 describes the required device simply as one that abates sounds from escaping or intaking gases, leaving the performance standard, not a brand or design mandate, as the test.