A. Any
sound or noise level measurement made pursuant to the provisions of
this chapter shall be measured with a sound level meter using the
A-weighting and slow response pursuant to applicable manufacturer's
instructions; except, that for sounds of a duration of two seconds
or less, the fast response shall be used and the average level during
the course of the occurrence of the sound reported.
B. The
sound level meter shall be appropriately calibrated and adjusted as
necessary by means of an acoustical calibrator of the coupler-type
to assure meter accuracy within the tolerances set forth in the most
current standards for sound level meters.
C. For
outside measurements, the microphone shall be not less than four feet
above the ground, at least four feet distant from walls or other large
reflecting surfaces, and shall be protected from the effects of wind
noises by the use of appropriate wind screens, and the location selected
shall be at any point on the affected property. In cases when the
microphone must be located within ten feet of walls or similar large
reflecting surfaces, the actual measured distances and orientation
of sources, microphone and reflecting surfaces shall be noted and
recorded. In no case shall a noise measurement be taken within five
feet of the noise source.
D. For
inside measurements, the microphone shall be at least three feet distant
from any wall, ceiling or partition, and the average measurement of
at least three microphone positions throughout the room shall be determined.
(Prior code § 36.403; Ord. 190, 1991)
A. Unless a variance has been applied for and granted pursuant to this chapter, it is unlawful for any person to operate, or cause to be operated, any single or combination of fixed source or nonstationary source type of equipment or machinery, except construction equipment used in connection with construction operations, that individually or collectively constitutes an identifiable sound source, in such a manner as to cause the average sound level at any point on or beyond the boundaries of the property on which the sound is produced to exceed by five decibels the noise level limits set forth in subsection
B of this section, plus allowances for time duration in subsection
C of this section.
B. Zone
Ambient Noise Level Limits. "Noise level limit" or "sound level limit"
referred to in this section means that noise level limit as determined
from the table below:
Zone
|
Time
|
Avg. Sound Level
|
---|
RL, RL/M, RM
|
7 AM to 7 PM
|
50
|
7 PM to 10 PM
|
45
|
10 PM to 7 AM
|
40
|
RM/H, RP
|
7 AM to 7 PM
|
60
|
7 PM to 10 PM
|
55
|
10 PM to 7 AM
|
50
|
All Commercial Zones
|
7 AM to 7 PM
|
60
|
7 PM to 10 PM
|
55
|
10 PM to 7 AM
|
55
|
LI
|
Anytime
|
70
|
The sound level limit at a location on a boundary between
two zoning districts shall be the arithmetic mean of the respective
limits for the two districts. Fixed location public utility distribution
or transmission facilities located on adjacent to a property line
shall be subject to noise level limits of this section, measured at
or beyond six feet from the boundary of the easement upon which the
equipment is located.
C. Time Duration Correction Table. The time duration allowances set forth in the table below shall apply to those noise level limits set forth in subsection
B of this section.
Allowances for Sound Levels Lasting Less Than an Hour
|
---|
Duration
|
Allowable Decibels
|
---|
Up to 30 minutes per hour (50%)
|
+3
|
Up to 15 minutes per hour (25%)
|
+6
|
Up to 10 minutes per hour (16%)
|
+8
|
Up to 5 minutes per hour (8%)
|
+11
|
Up to 2 minutes per hour (3%)
|
+15
|
D. Permissible construction noise level limits shall be governed by Section
9.24.120.
(Prior code § 36.404; Ord. 190, 1991)
It is unlawful for any person to operate any powered model vehicle except between the hours of seven a.m. and nine p.m. and then only in such a manner so as not to emit noise in excess of those levels set forth in Section
9.24.080; however, if powered model vehicles are operated in public parks at a point more than one hundred feet from the property line, the noise level shall be determined at a distance of one hundred feet from the noise source instead of at the property line, and noises from powered model vehicles, measured at that distance in excess of the noise limits specified in Section
9.24.080, are prohibited.
(Prior code § 36.406)
No person shall operate, or permit to be operated, a refuse
compacting, processing, or collection vehicle within the city which,
when compacting, creates a sound level in excess of eighty decibels
when measured at a distance of fifty feet from any point of the compacting
vehicle, unless a variance has been applied for and granted pursuant
to this chapter.
(Prior code § 36.407)
It is unlawful for any person to handle or transport, or cause
to be handled or transported, in any public place, any container or
any construction material in such a way as to create a disturbing,
excessive, or offensive noise as defined under Section 9.24.020(F).
(Prior code § 36.411)
No person shall operate, or cause to have operated or used,
any sound signal device, other than sound-amplification equipment,
attached to a motor vehicle wagon or manually propelled cart from
which food or any other items are sold which emits a sound signal
more frequently than once every ten minutes in any one street block
and with a duration of more than ten seconds for any single emission.
The sound level of this sound signal shall not exceed ninety decibels
at fifty feet.
(Prior code § 36.412)
Notwithstanding any other provisions of this chapter, it is unlawful for any person to create, maintain, or cause to be maintained, any sound within the interior of any multiple-family dwelling unit which causes the average sound level of forty-five decibels to be exceeded in any other dwelling unit for a cumulative period of five minutes in any one hour, or fifty decibels for a cumulative period of one minute in any one hour, or fifty-five decibels at no time between the hours of ten p.m. of one day and seven a.m. of the following day. The monitoring procedures outlined under Section
9.24.070 shall be followed in enforcing this section.
(Prior code § 36.413)