“Opacity” means the degree to which emissions reduce the transmission of light and obscure the view of an object in the background.

Source. #1717, eff 2-19-81; ss by #2332, eff 4-29-83; ss by #2938, eff 12-27-84; ss by #5033, eff 12-27-90; ss and moved by #6057-A, eff 6-30-95 (from Env-A 101.64); renumbered by #8256 (from Env-A 101.198), (see Revision Note #1 at chapter heading); renumbered by #8304 (see Revision Note #2 at chapter heading); renumbered by #9839 (from Env-A 101.134), (see Revision Note #3 at chapter heading); ss by #13105, eff 9-25-20 (formerly Env-A 101.136) (see Revision Note #4 at chapter heading for Env-A 100)