OAR 340-256-0100: Visible Emissions: General Requirements, Exclusions

(1) A person may not operate, drive, or cause or permit to be driven or operated any motor vehicle upon public roads that emits into the atmosphere any visible emission. (2) Excluded from this rule are those motor vehicles: (a) Powered by diesel cycle engines; (b) Granted a variance by written order of DEQ under ORS 468A.075. (3) A person may not operate, drive, or cause or permit to be driven or operated any motor vehicle upon public roads if any element of the factory-installed motor vehicle pollution control system has been modified or altered in such a manner that decreases its efficiency or effectiveness in controlling air pollution in violation of ORS 815.305, except as noted in ORS 815.305(2). [NOTE: This rule is included in the State of Oregon Clean Air Act Implementation Plan that EQC adopted under OAR 340-200-0040.]