US lawWashingtonRegulationsTitle 173 — ECOLOGY, DEPARTMENT OFChapter 173-421 — MOTOR VEHICLE EMISSION CONTROL SYSTEMS173-421-010WAC 173-421-010WAC 173-421-010. PurposeLast amended: 1987Year: 2026Length: 19 wordsOfficial source This chapter promulgated under RCW 70.94.305 and 70.94.331 establishes requirements to preserve emission control equipment installed on motor vehicles.NextWAC 173-421-020