Norwalk, CT Noise Ordinances: Decibel Limits (2026)

Section 68-5A bars operating any sound source in a way that exceeds the limits in Table 1 for the receiving property's use category, measured at or within its property line. Table 1 sets outdoor limits of 55 dBA residential daytime, 45 dBA residential nighttime, 63 dBA commercial 24 hours, and 70 dBA industrial 24 hours; indoor limits run lower, at 45, 35, 55 and 60 dBA respectively, and indoor readings are only taken when the source and receiver share a building or a common wall, floor or ceiling.

Impulsive sound gets a separate daytime cap of 60 dBA under § 68-5A(2)(a), reverting to Table 1 limits at night. A list of exclusions in § 68-5B removes natural phenomena, church and school bells, emergency sirens, OSHA-required warning devices, and properly muffled agricultural engines from the limits entirely. Section 68-5C carves out additional exceptions with their own conditions, including a 50 dBA nighttime cap specifically for residential HVAC equipment (§ 68-5C(10)) and a 60 dBA cap at the property line for generator testing (§ 68-5C(12)).

Measurements must follow the procedures in § 68-4, including calibrating the meter before and after use and taking readings at least one foot inside the affected property's line.