The volume of sound inherently and recurrently generated shall not exceed the following standards at any point along the boundaries of the zone in which the use is located:

1. Objectionable sounds of an intermittent nature shall be controlled so as not to become a nuisance to adjacent uses.
   
2. Maximum sound pressure levels shall be measured with a sound level meter and associated octave band analyzer conforming to standards prescribed by the American Standards Association and shall not exceed the values for octave bands lying within the several frequency limits given in the following table after the application of appropriate corrections:
   
   B-1 and B-2 Districts
   
   

Frequency Ranges Containing Standard Octave Bands in Cycles Per Second	Octave Band Sound Pressure Level in Decibels
0—74	72
75—149	67
150—299	59
300—599	52
600—1,199	46
1,200—2,399	40
2,400—4,800	34
Above 4,800	32

Type of Operation or Noise	Correction in Decibels
Daytime operation only	+ 5Noise of impulsive character
(e.g., hammering)	- 5Noise of periodic character
(e.g., hum, screech)	- 5

I-1 District

Frequency Ranges Containing Standard Octave Bands in Cycles Per Second	Octave Band Sound Pressure Level in Decibels
0—74	79
75—149	74
150—299	66
300—599	59
600—1,199	53
1,200—2,399	47
2,400—4,800	41
Above—4,800	39

Type of Operation or Noise	Correction in Decibels
Daytime operation only	+ 5
Noise of impulsive character (e.g., hammering)	- 5
Noise of periodic character (e.g., hum, screech)	- 5

1. Dust. No solid or liquid particles shall be emitted in concentrations exceeding 0.3 grains per cubic foot of the conveying gas or air.
2. Fly Ash.
   1. No emission or fly ash in excess of the quantity specified in the following table shall be permitted:
      
      

      Heat in Fuel Burned (British Thermal Units Per Hour)	Fly Ash: Rate of Emission (Lbs. per Hour)
      1,000,000	1
      100,000,000	100
      400,000,000	330
      1,000,000,000	750
      2,000,000,000	1,365
      3,000,000,000	1,850
      4,000,000,000	2,260
      5,000,000,000	2,640
      6,000,000,000	2,950
      7,000,000,000	3,200
      8,000,000,000	3,410
      10,000,000,000	3,750

   2. For heat content between any two (2) consecutive heat contents given in the Table, the fly ash limitation shall be as determined by interpolation.
3. Smoke. No emission of smoke from any source, as measured on the Ringelmann Chart published by the United States Bureau of Mines, shall be permitted in excess of:
   1. In a Business District, a density described as Ringelmann No. 2, provided that a density equal to Ringelmann No. 3 may be emitted for not more than three (3) minutes in any fifteen (15) consecutive minutes.
   2. In an Industrial District, a density described as Ringelmann No. 3.