§ 155.394  PERFORMANCE STANDARDS; NOISE.
   (A)   For the purpose of measuring the intensity and frequency of sound, the sound level meter, the octave band analyzer and the impact noise analyzer shall be employed.
   (B)   The flat network and the fast meter response of the sound level meter shall be used. Sounds of very short duration, as from forge hammers, punch presses and metal shears which cannot be measured accurately with the sound level meter shall be measured with the impact noise analyzer.
   (C)   Octave band analyzers calibrated in the Preferred Frequencies (American Standards Association S1.6 - 1960, Preferred Frequencies for Acoustical Measurements) shall be used in the table headed “Octave Band, Preferred Frequencies.” Octave band analyzers calibrated with the pre-1960 octave bands (American Standards Association Z24.10 -1953, Octave Band Filter Set) shall be used with the tables headed “Octave Band, Pre-1960.”
   (D)   The following uses and activities shall be exempt from the noise level regulations:
      (1)   Noises not directly under the control of the property user;
      (2)   Noises emanating from construction and maintenance activities between 7:00 a.m. and 9:00 p.m.;
      (3)   The noises of safety signals, warning devices and emergency pressure relief valves; and
      (4)   Transient noises of moving sources such as automobiles, trucks, airplanes and railroads.
   (E)   The decibel values specified for residence districts shall be reduced by six decibels between the hours of 7:00 p.m. and 7:00 a.m.
   (F)   (1)   In the M1 District, the generation of noise shall not exceed the decibel limits prescribed below.
Maximum Permitted Sound Levels in Decibels (Re. 0002 Microbar)
Octave Band Pre-1960 (Cycles per Second)
Neighboring Lot
Residence District
Maximum Permitted Sound Levels in Decibels (Re. 0002 Microbar)
Octave Band Pre-1960 (Cycles per Second)
Neighboring Lot
Residence District
20 - 75
79
72
75 - 150
74
67
150 - 300
66
59
300 - 600
59
52
600 - 1,200
53
46
1,200 - 2,400
47
40
2,400 - 4,800
41
34
above
39
32
 
Octave Band Preferred Frequencies (Cycles per Second)
Neighboring Lot
Residence District
Octave Band Preferred Frequencies (Cycles per Second)
Neighboring Lot
Residence District
31.5
83
76
63
78
71
125
72
65
250
64
57
500
57
50
1,000
51
50
2,000
46
39
4,000
41
34
8,000
38
32
 
      (2)   Impact noises measured on an impact noise analyzer shall not exceed the following peak intensities:
 
Neighboring Lot
Residence District
Overall peak
86
80
 
   (G)   (1)   In the M2 District, the generation of noise shall not exceed the decibel limits prescribed below:
Maximum Permitted Sound Levels in Decibels (Re. 0002 Microbar)
Octave Band Pre-1960 (Cycles per Second)
Neighboring Lot
Residence District
Maximum Permitted Sound Levels in Decibels (Re. 0002 Microbar)
Octave Band Pre-1960 (Cycles per Second)
Neighboring Lot
Residence District
20 - 75
82
72
75 - 150
77
67
150 - 300
69
59
300 - 600
62
52
600 - 1,200
56
46
1,200 - 2,400
50
40
2,400 - 4,800
44
34
4,800 - 10KC
42
32
 
Octave Band Preferred Frequencies (Cycles per Second)
Neighboring Lot
Residence District
Octave Band Preferred Frequencies (Cycles per Second)
Neighboring Lot
Residence District
31.5
86
76
63
81
71
125
75
65
250
67
57
500
60
50
1,000
54
45
2,000
49
39
4,000
44
34
8,000
41
32
 
      (2)   Impact noises measured on an impact noise analyzer shall not exceed the following peak intensities in decibels:
 
Neighboring Lot
Residence District
Overall peak
90
80
 
(Ord. 1999-2, Zoning § 16, subs. .050, passed 2-15-1999)