Discharge into the atmosphere of air contaminants including, but not limited to, sulfur compounds, smoke, charred paper, dust, soot, grime, carbon, noxious acids, fumes, gases, mist, odors or particulate matter or any combination thereof, from any single source of emission whatsoever for a period or periods aggregating more than three minutes in any one hour shall not be permitted which:
1. Exceeds the legally permissible discharge limits, if any, established by state or local code and enforced by the air pollution control district of the county; or
2. Is as dark or darker in shade as that designated as No. 2 on the Ringlemann Chart, as published by the United States Bureau of Mines; or
3. Is of such opacity as to obscure an observer's view to a degree equal to or greater than the smoke described above.