Nashua, NH Noise Ordinances: Decibel Limits (2026)

Unlike Washington cities operating under WAC 173-60-040's source-to-receiving-class dBA matrix or California cities operating under fixed-hour dBA tables, Nashua regulates noise primarily through reasonableness plus specific quantitative triggers. The Chapter 201 (Noise) framework: (1) 50-foot audibility prima facie rule - operation of any electronic sound-reproduction device (radio, TV, stereo, loudspeaker, sound amplifier, etc.) at volume clearly audible at 50 feet from the source is prima facie evidence of a violation. (2) Motor-vehicle audio rule at NCO 201-1 - electrically amplified sound system in or on a motor vehicle producing sound clearly audible more than 50 feet from the vehicle. (3) Public-street vocal rule - yelling, shouting, hooting, whistling, singing on public streets 11:00 p.m. - 7:00 a.m. (4) Disturbance standard - 'disturb the peace, quiet and comfort of inhabitants of neighboring premises' applies at all hours. The Chapter 190 (Land Use Code) HVAC / mechanical-equipment standard is the city's only explicit numeric dBA cap: mechanical appurtenances (heating and air-conditioning equipment) located on the exterior portion of structures shall include any necessary sound buffer and/or noise attenuation equipment sufficient to reduce sound levels to 50 decibels during the daytime hours (7:00 a.m. to 8:00 p.m.) and 45 decibels during the nighttime hours (8:00 p.m. to 7:00 a.m.), measured at residential zoning district boundaries. The Nashua City Planning Board's site-plan checklist incorporates this standard into mechanical equipment review at site-plan and design-review stages. There is no general citywide dBA cap for industrial sources, construction, music, or animals - those rely on the disturbance / reasonableness standard plus the Chapter 128 construction quiet window (8 p.m. - 7 a.m. weekdays). On the motor-vehicle side, NH RSA 266:59 (motor-vehicle equipment) requires every motor vehicle to be equipped with a muffler in good working order to prevent excessive or unusual noise - a state-law backstop frequently cited alongside NCO 201-1 in Nashua Police enforcement. NH RSA 644:2 (disorderly conduct) supplies the statewide reasonableness backstop - loud or unreasonable noise that would disturb a person of average sensibilities is a violation (up to $1,000) or a Class B misdemeanor if continued after desist order. The federal occupational-noise framework (29 CFR 1910.95 OSHA) governs workplace exposure but does not regulate community noise.