27.56.100 SMOKE—PARTICULATE MATTER.

(a) 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. For the purposes of grading density of emissions, the Ringelmann chart published and used by the United States Bureau of Mines shall be employed.

(b) 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 and during any one hour, computed in accordance with the procedures set forth in Chapter 27.76.

(c) 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 (b) above.