1143.06 PERFORMANCE STANDARDS.
   Any use established hereafter in any M-1 District shall be so operated as to comply with the performance standards set forth as follows:
   (a)    Noise. Sound levels shall be measured with a sound level meter and associated octave band filter manufactured according to standards prescribed by the American National Standards Institute, Inc. Measurements shall be made using the flat network of the sound level meter. Impulsive-type noises shall be subject to the performance standards hereinafter prescribed provided that such noises are capable of being accurately measured with sound equipment. Noises capable of being so measured, for the purpose of this Zoning Ordinance, shall be those noises which cause rapid fluctuations of the needle of the sound level meter with a variation of no more than plus or minus two decibels. Noises incapable of being so measured, such as those of an irregular or intermittent nature, shall be controlled so as not to become a nuisance to adjacent uses.
   At no point either on the boundary of a residence district or a business district, or at 125 feet from the nearest property line of a plant or operation, whichever distance is greater, shall the sound pressure level of an individual operation or plant, other than the operation of motor vehicles and other transportation facilities, exceed the decibel levels at the designated octave bands shown here for the districts indicated:
 
       Maximum Permitted Sound Level
       Along Boundaries, or 125 Feet
       From Plant or Operation Property Line
                           (in decibels)
Octave Band          Residence    Business
Cycles per Second       Districts    Districts
0 to 75           67        73
75 to 150           62        68
150 to 300           58        64
300 to 600           54        60
600 to 1,200           49        55
1,200 to 2,400        45        51
2,400 to 4,800        41        47
Above 4,800           37        43
   (b)    Smoke and Particulate Matter.
      (1)    No stack shall emit more than ten smoke units during any one hour, nor shall smoke of a density in excess of Ringelmann No. 2 be emitted, provided that during a single one-hour period in each twenty-four hour day each stack may emit up to twenty smoke units when blowing soot or cleaning fires, and during such cleaning of fires, smoke of a density of Ringelmann No. 3 may be emitted, but not for longer than four minutes each period.
      (2)    No emission of smoke or particulate matter shall exceed a density of Ringelmann No. 3, except for a plume consisting entirely of condensed steam. For the purpose of grading the density of emission, the Ringelmann Chart published and used by the United States Bureau of Mines shall be employed.
      (3)    The rate of emission of particulate matter from all sources within the boundaries of any lot shall not exceed a net figure of one pound per acre of lot area during any one hour.
      (4)    Dust and other forms of air pollution borne by the wind from such sources as storage areas, yards, roads and so forth, within lot boundaries shall be kept to a minimum by appropriate landscaping, paving, oiling or other acceptable means. The emission of particulate matter from such sources shall conform with the requirements of subparagraph (3) hereof.
      (5)    In addition to the performance standards specified herein, the emission of smoke or particulate matter in such manner or quantity as to be detrimental to or endanger the public health, safety, comfort or welfare is hereby declared to be a public nuisance.
   (e)    Odorous Matter. The emission of odorous matter from any property in such concentrations as to be readily detectable at any point along the boundaries of such property or in such concentrations as to create a public nuisance or hazard beyond such boundaries is prohibited.
   (d)    Vibration. Any process or equipment which produces intense earth-shaking vibrations, such as are created by heavy drop forges or heavy hydraulic surges, shall be set back at least 500 feet from the property boundaries on all sides, except for a property line adjoining an M-3 District, where such setback shall not be mandatory. However, in no case shall such vibrations be allowed to create a public nuisance or hazard beyond the property boundaries.
   (e)    Toxic or Noxious Matter. No use on any property shall discharge across the boundaries of the property toxic or noxious matter in such concentrations as to be detrimental to or endanger the public health, safety, comfort or welfare, or cause injury or damage to other property or business.
   (f)    Glare or Heat. Any operation producing intense glare or heat shall be performed within a completely enclosed building and effectively screened in such a manner as not to create a public nuisance or hazard along property boundaries.
   (g)    Fire and Explosive Hazards. Fire and explosive hazards shall be controlled as follows:
      (1)    Activities involving the storage or manufacture of materials ranging from incombustible to moderate burning, as determined by the Zoning Administrator, are permitted.
      (2)    The storage, use or manufacture of materials or products ranging from free-to-active burning-to intense burning, as determined by the Zoning Administrator, is permitted under the following conditions:
         A.    All storage, use or manufacture of such materials or products shall be within completely enclosed buildings or structures having incombustible exterior walls; and
         B.    All such buildings or structures shall be set back at least forty feet from property boundaries or, in lieu thereof, shall be protected throughout by an automatic sprinkler system complying with standards for installation prescribed by the National Fire Protection Association.
      (3)    Activities involving the storage or manufacture of materials or products which decompose by detonation are not permitted in M-1 Districts.
      (4)    Materials or products which produce flammable or explosive vapors or gases under ordinary weather temperatures shall not be permitted in this district, with the exception of the following, which are permitted:
         A.    Materials required for emergency or standby equipment;
         B.    Materials used in secondary processes which are auxiliary to a principal operation, such as paintspraying of finished products; and
         C.    Flammable liquids and oils stored, sold and used in conjunction with the operation of any automobile service station and customarily required or used in such operation.
            (Ord. 10-16-67. Passed 11-20-67.)