(a) No person in any commercial district may generate noise or permit noise to be generated that tends to have an annoying or disruptive effect upon others within or outside the district regardless if the noise so generated is a result of one or more uses upon the lot within the commercial district.
(b) No person in any industrial district may generate or cause to be generated noise in excess of that as established in subsection (c) of this section.
(c) Except as provided in subsection (g) of this section, the table set forth in subsection (f) of this section establishes the maximum permissible noise levels in the I-1 and I-2 districts. Measurements shall be taken at the boundary line of the lot where the enterprise or enterprises that are generating the noise are located; however, as indicated, the maximum permissible noise levels may vary according to the zoning of the lot adjacent to the industrial zoned lot on which the enterprise or enterprises that are generating the noise are located.
(d) A decibel is a measure of a unit of sound pressure. Since sound waves having the same decibel level "sound" louder or softer to the human ear depending upon the frequency of the sound wave in cycles-per-second (i.e., whether the pitch of the sound is high or low) and A- weighted filter constructed in accordance with the specifications of the American National Standards Institute, which automatically takes into account the varying effect on the human ear of different pitches, shall be used on any sound level meter taking measurements required by this section and accordingly, any measurements are expressed in dB(A) to reflect the use of this A- weighted filter.
(e) The standards established in the table are set forth in subsection (f) of this section and expressed in terms of the Equivalent Sound Level (Leq), which must be calculated by taking 100 instantaneous A-weighted sound levels at 10 second intervals.
(f) Table of Maximum Permitted Sound Levels, dB(A).
TABLE OF MAXIMUM PERMITTED SOUND LEVELS, dB(A)
ZONING DISTRICT | WHEN ADJACENT TO: | WHEN ADJACENT TO: | |||
All Residential Zones and PD’s | |||||
7 a.m. - 7 p.m. | 7 p.m. - 7 a.m. | C-1, C-2, C-3, C-4, C-5 | I-1 | I-2 | |
I-1 | 50 | 45 | 55 | 80 | 80 |
I-2 | 50 | 45 | 60 | 80 | 80 |
Note: 0.0002 Microbar
(g) Impact noises are sounds that occur intermittently rather than continuously. Impact noises generated by sources that do not operate more than one minute in any one-hour period are permissible up to a level of 10 dB(A) in excess of the figures listed in subsection (f) of this section, except that this higher level of permissible noise shall not apply from 7 p.m. to 7 a.m. when the adjacent lot is zoned residential. The impact noise shall be measured using the fast response of the sound level meter.
(h) Noise resulting from temporary construction activity that occurs between 7 a.m. and 7 p.m. shall be exempt from the requirements of this Section.
(Ord. 074-10. Passed 12-20-10.)