§ 159.381 PERFORMANCE STANDARDS.
   (A)   Physical appearance.
      (1)   All operations shall be carried on within an enclosed building, except that new materials or equipment in operable condition may be stored in the open. Normal daily wastes of an inorganic nature may be stored in containers not in a building when such containers are not readily visible from the street. The provisions of this paragraph shall not be construed to prohibit the display of merchandise or vehicles for sale or the open storage of vehicles, boats, farm machinery, trailers, mobile homes or similar equipment when in operable condition.
      (2)   Contractors’ storage yards, equipment storage yards, junk, salvage, auto wrecking and similar operations shall be screened from view from streets and from adjacent properties and other zoning districts by means of a sight-obscuring fence, not to exceed a height of 80 inches, approved by the City Inspector or his or her designee. The fence shall be maintained in good repair. The fence shall be constructed within a period of 90 days after notification by the City Building Inspector or his or her designee after the date of passage of this chapter.
      (3)   Temporary recreational uses approved as a conditional use shall not involve any appreciable amount of fixed construction and shall not interfere with the efficient functioning of the district for its primary purpose of providing for industrial uses.
   (B)   Fire hazard. All flammable substances involved in any activity established in this district shall be handled in conformance with the standards of the National Board of Fire Underwriters, National Fire Protection Association, OSHA and any additional regulations of the city.
   (C)   Noise. All noise and noise-causing activities shall be muffled so that they will not create a disturbance greater than normal peak hour traffic noise on a major street when observed from any area zoned residential. Major street noise, for comparison purposes, shall be measured on the primary state highway nearest the industry.
   (D)   Sewage and liquid waste. No operation shall be carried on which involves the discharge into a sewer, water course or the ground of liquid wastes of any radioactive nature or liquid wastes of a chemical nature which are detrimental to normal sewage plant operation or corrosive and damaging to sewer pipes and installations. Any liquid wastes that create heavy loading on the city sanitary system will be subject to treatment by the owner, according to reasonable industrial standards, before being discharged into the city sewer system or by other agreement with the City Council.
   (E)   Air contaminants.
      (1)   Air contaminants and smoke shall be less dark than designated Number Two on the Ringleman Chart, as published by the United States Bureau of Mines, except that smoke of a density designated as Number Two shall be permitted for one period of four minutes in each one-half hour. Light-colored contaminants of such opacity as to obscure an observer’s view to a degree equal to or greater than the aforesaid shall not be permitted.
      (2)   Particulate matter of dust, as measured at the point of emission by any generally accepted method, shall not be emitted in excess of two-tenths grains per cubic foot, as corrected to a temperature of 500°F.
      (3)   Due to the fact that the possibilities of air contamination cannot reasonably be comprehensively covered in this section, there shall be applied the general rule that there shall not be discharged, from any source whatsoever, such quantities of air contaminants or other material in such quantity as to cause injury, detriment, nuisance or annoyance to any considerable number of persons or to the public in general, or to endanger the comfort, repose, health or safety of any such considerable number of persons, or to cause or have a natural tendency to cause injury or damage to business, vegetation or property.
   (F)   Odor. Odor-causing operations shall be controlled so as to reduce the escape of odors to the minimum practical within the limits of technology and economics.
   (G)   Gases. All noxious gases shall be controlled to the extent that they will not be injurious to life and property. The gases sulfur dioxide and hydrogen sulfide shall not exceed five parts per million, carbon monoxide shall not exceed 25 parts per million and nitrous fumes shall not exceed five parts per million. Measurements shall be taken at the zoning lot line.
   (H)   Vibration. All machines, including punch presses and stamping machines, shall be so mounted as to minimize vibration. Vibration shall not be so excessive that it interferes with industrial operations on nearby zoning lots.
(Prior Code, § Q-7-107) Penalty, see § 159.999