§ 34-86. Exterior noise standards.

(a)

The following noise standards, unless otherwise specifically indicated in this article, shall apply to all properties within a designated noise area, measured pursuant to section 34-85(b):

Noise Area	City Zoning Districts	Time Period	Exterior Noise Standard
1	RD-1, RD-2, RD-3, RD-4, RD-5, R-7, RD-10, R15, RD-20, R-25, RD-30, MH	7:00 a.m. to 10:00 p.m. (Daytime) 10:00 p.m. to 7:00 a.m. (Nighttime)	55 dBA (Leq) 50 dBA (Leq)

 

(b)

It is unlawful for any person at any location within the city to create any noise which causes the noise levels on an affected property, when measured in the designated noise area pursuant to section 34-85(b), to exceed, for the duration of time set forth following, the specified exterior noise standards in any one hour by:

Cumulative Duration of the Intrusive Sound

Allowance Decibels

 

(1)

Cumulative period of 30 minutes per hour ..... 0

(2)

Cumulative period of 15 minutes per hour ..... +5

(3)

Cumulative period of five minutes per hour ..... +10

(4)

Cumulative period of one minute per hour ..... +15

(5)

Level not to be exceeded for any time per hour ..... +20

(c)

Each of the noise limits specified in subsection (b) of this section shall be reduced by five dBA for impulsive or simple tone noises or for noises consisting of speech or music.

(d)

If the ambient noise level exceeds that permitted by any of the first four noise limit categories specified in subsection (b) of this section, the allowable noise limit shall be increased in five-dBA increments in each category to encompass the ambient noise level. If the ambient noise level exceeds the fifth noise level category, the maximum ambient noise level shall be the noise limit for that category.

(e)

It is unlawful for any person at any location within the city to create low-frequency noise or impulsive noise which causes the noise level on an affected residential property to exceed the noise level standards as indicated below. Exterior noise level shall be measured pursuant to the requirements set forth in section 34-85(b).

Sound Level Descriptor	Daytime (7:00 a.m. to 10:00 p.m.)	Nighttime (10:00 p.m. to 7:00 a.m.)
Leq, A weighting dBA	50	45
Leq, C weighting dBC	75	70
One-third octave band	10 dB increase in any one-third octave band

 

(1)

The noise level measurements conducted under this subsection (e) shall be conducted with the sound level meter set to fast response.

(2)

If separation of low frequency noise or impulsive noise from the background ambient noise can be determined with the sound level meter set to A-weighting, noise levels from the low frequency noise shall not exceed an Leq of 50 dBA daytime and 45 dBA nighttime for any one minute period.

(3)

If separation of low frequency noise or impulsive noise from the background ambient noise cannot be determined with the sound level meter on A-weighting, the meter shall be switched to C-weighting to emphasize the low frequency noise. If separation of low frequency noise or impulsive noise from background ambient noise can be determined with the meter set to the C-weighting, the noise level from the low frequency noise or impulsive noise shall not exceed an Leq of 75 dBC daytime and 70 dBC nighttime for any one minute period.

(4)

If existing background ambient noise levels are higher than standards identified in the table above, then the maximum sound levels due to amplified sound shall not exceed the background sound levels by more than three dB for A-weighted measurements and five dB for C-weighted measurements.

(5)

If separation of low frequency noise or impulsive noise from the background ambient noise cannot be determined with the sound level meter set to either A or C weighting, and low frequency noises or impulsive noise are clearly audible to the acoustics specialist, a sound level measurement shall be taken using one-third octave band frequencies. A 10 dB increase in any one-third octave band due to the amplified noise shall be considered a violation of this article.

(Ord. No. 2015-011, § 1, 1-14-2016)