(a) Stationary Source: No person shall permit or cause the emission of any smoke, which smoke exceeds the following permissible limitations, from any stationary source except from fireplaces in residential units and outdoor cooking facilities accessory to residential units. The emission limitations are as follows:
(1) Smoke of a density, shade or opacity equal to but not greater than no. 1 on the Ringelmann chart may be emitted for a maximum period of four (4) minutes out of every half hour.
(2) Smoke of a density, shade or opacity equal to but not greater than no. 2 on the Ringelmann chart may be emitted for a maximum period of four (4) minutes out of every two (2) hours.
(3) The emission of smoke of a density, shade or opacity greater than no. 2 on the Ringelmann chart is not permissible.
(b) Nonstationary Source: No person shall permit or cause the emission of any smoke from a nonstationary source of a density, shade or opacity greater than no. 2 on the Ringelmann chart with the exemption of diesel powered vehicles during the first fifteen (15) seconds after accelerating from a stationary position, when they shall be permitted not greater than no. 3 on the Ringelmann chart and with the exemption of home grills. (M.C. 1963, § 18.413; amd. Ord. 0-70-32)