For use in this chapter, the following terms are defined:
A-WEIGHTED SOUND LEVEL
The sound pressure level in decibels as measured on a sound
level meter using the A-weighting network. The level so read is designated
dBA.
CONSTRUCTION EQUIPMENT
The implements used in an operation or activity, or everything
except personnel needed to build, to repair, or to erect.
DECIBEL
A unit for measuring the volume of a sound, equal to 20 times
the logarithm to the base 10 of the ratio of the pressure of the sound
measured to the reference pressure, which is 20 micropascals (20 micronewtons
per square meter).
EXHAUST SYSTEM
The device or combination of devices that collects the exhaust
from the engine or motor, delivers the exhaust to the atmosphere and
reduces the noise emissions. "Exhaust system" includes manifold or
headers, exhaust pipe, muffler, and tail pipe.
FARM EQUIPMENT
The implements used in an operation or activity, or everything
except personnel needed for cultivation or production of crops of
any nature, or raising of any type of animal embraced within the term
"livestock."
NOISE DISTURBANCE
For purposes of this chapter, means any transmission of sound
across a real property boundary from a source specifically limited
by this chapter, which exceeds the sound level limits set forth in
Table 1 entitled "Maximum Permissible Sound Levels From Limited Sources
by Receiving Land Use."
Table 1
Maximum Permissible Sound Levels From Limited Sources By Receiving
Land Use
|
---|
Zoning Category of Receiving Land Use
|
Legal Time
|
Sound Level Limit
(dBA)
|
---|
Residence district
|
7:00 a.m. to 10:00 p.m.
10:00 p.m. to 7:00 a.m.
|
60
50
|
Commercial district
|
At all times
|
65
|
Industrial district
|
At all times
|
75
|
REAL PROPERTY BOUNDARY
An imaginary line along the ground surface, and its vertical
extension, which separates the real property owned by one person from
that owned by another person, but not including intra-building real
property divisions.
RECEIVING LAND USE
For purposes of this chapter, the use or occupancy of the
property which receives the transmission of sound.
RESIDENTIAL or RESIDENTIAL DISTRICT
Any property on which is located a building or structure
used wholly or partially for living or sleeping purposes. This definition
does not include park custodial residences or school or college dormitories.
SOUND
An oscillation in pressure, particle displacement, particle
velocity or other physical parameter, in a medium with internal forces
which cause compression and rarefaction of that medium. The description
of sound may include any characteristic of sound, including duration,
density, and frequency.
SOUND LEVEL
The weighted sound pressure level contained by the use of
the sound level meter and A-weighting network, such as a, b or c as
specified in American National Standards Institute Specifications
for Sound Level Meters, ANSI S1.4. If the frequency weighting employed
is not indicated, the A-weighting shall apply.
[Amended 3-23-2023 by Ord. No. 23-02]
SOUND PRESSURE
The instantaneous difference between the actual pressure
and the average or barometric pressure at a given point in space,
as produced by sound energy.
SOUND-PRESSURE LEVEL
Twenty times the logarithm to the base 10 of the ratio of
the root mean squared sound pressure to the reference pressure of
20 micropascals.
USED or OCCUPIED
For purposes of this chapter, where either word appears,
shall be deemed to include the words "intended, designed, or arranged
to be used or occupied."
[Ord. No. 17-19; amended 10-19-2023 by Ord. No.
23-25]
A. The provisions of this chapter which prohibit the making, continuing, or causing the making or continuance of a noise disturbance shall be enforced only upon receipt of a complaint made or filed with City officials by a person disturbed by such noise disturbance, with the exception of violations of §
218-2A(1),
(2) and
(3). Certification by an official charged with enforcement of the provisions of this chapter that such complaint was made shall be sufficient to establish a rebuttable presumption that a violation of this statute has occurred.
B. Peace officers may enforce violations of §
218-2A(1),
(2) and
(3) of this chapter without necessity of such complaint.
C. Any person
who fails to perform any act required by the provisions of this chapter
or commits an act prohibited by this chapter shall be guilty of a
simple misdemeanor or municipal infraction.
D. The penalty for misdemeanor violations of §
218-2A(3) shall be the same as provided for violations of Iowa Code § 321.436 in Iowa Code § 805.8A. The penalty for all other misdemeanor violations shall be the same as provided for simple misdemeanors in Iowa Code § 903.1.
[Ord. No. 02-22]
The Council, on written application, for good cause shown, may grant a special permit to exceed the sound and/or time limits established in §
218-1 for specific activities generally or for limited times and/or dates, provided that the sound level does not exceed 75 dBA at the receiving land use.