12-2-5: AIR QUALITY:
Any land use shall be operated so that air quality conforms with all applicable state or federal regulations. In addition:
   A.   Smoke: No emission of smoke from any source shall be permitted to exceed a greater density than the density described in no. 1 on the Ringleman chart. However, smoke may be emitted, which is equal to, but not darker, than no. 2 on the Ringleman chart, for not more than four (4) minutes in any eight (8) hour period. For the purpose of grading the density of smoke, the Ringleman chart, as published by the U.S. bureau of mines, shall be the standard. All measurements shall be taken at the point of emissions of the smoke.
   B.   Fly Ash, Dust, Fumes, Vapors, Gases And Other Forms Of Air Pollution: No emission shall be permitted which can cause damage to health, animals or vegetation, or other forms of property, or which can cause any excessive soiling. (2006 Code)