(a) No person shall cause or permit the emission of an air contaminant of:
(1) A density which appears as dark or darker than number two on the standard smoke chart or of an opacity which obscures vision to a degree equal to or greater than smoke of number two density on the standard smoke chart; or
(2) A density which appears as dark or darker than number one on the standard smoke chart, but less than number two on said chart, or of such opacity as to obscure vision to a degree equal to or greater than smoke of number one density on the standard smoke chart, but less than number two on said chart, if such an emission continues for longer than two minutes in the aggregate in any sixty minute period.
(b) (1) The density or opacity of an air contaminant shall be measured in accordance with the procedures set forth in "Method 9 - Visual determination of the opacity of emissions from stationary sources," Appendix A-4 to 40 CFR part 60.
(2) The density or opacity of an air contaminant shall be measured at the point of its emission provided that:
(i) When the point of emission cannot be readily observed, it may be measured at an observable point on the plume nearest the point of emission; or
(ii) In the case of an air contaminant emitted from a source outside of the city of New York, it shall be measured after the plume crosses the jurisdictional boundary of the city of New York.
(Am. L.L. 2015/038, 5/6/2015, eff. 5/6/2016)