Beloit, WI Noise Ordinances: Decibel Limits (2026)

Section 8-801 of the Zoning Code's industrial performance standards sets numeric noise ceilings that apply only where a Manufacturing (M) district touches a Residential (R) or Commercial (C) district. Sound is measured with a sound level meter and octave band filter built to American Standards Association specifications, using the meter's flat network, and the section separately provides for irregular or intermittent noises that cannot be captured that way, which must instead simply avoid becoming a nuisance to adjacent uses. For noise that can be measured, subsection b sets a maximum permitted sound level in decibels for each of eight octave bands, split by whether the measurement point sits along a Residential district boundary or a Commercial district boundary.

At 0 to 75 cycles per second the limit is 72 decibels at a residential boundary and 79 at a commercial boundary; the ceiling drops through the bands to 46/53 decibels at 600 to 1,200 cycles, and bottoms out at 32/39 decibels above 4,800 cycles. Background noise from sources outside the operator's control, such as passing motor vehicles or other transportation, is excluded from the calculation. The same 8-800 series regulates vibration in section 8-802 using a displacement formula, and separately caps industrial glare at one footcandle at a Residential boundary in section 8-806.

Because the standard is tied to the M-district boundary with an R or C district, it does not apply to noise generated and measured entirely within a Manufacturing district, or between two Manufacturing districts.