The Road to Cleaner Cars… (Text Only)
See: Infographic version of this information
1970: Clean Air Act (CAA) passed; emission standards set for cars and light-duty truck
1975: Emission Standards Take Effect
1979: Congress amends the CAA and passes more stringent standards
1981: Congress further tightens standards
1990: CAA amended again; Tier 1 standards set
1994: Tier 1 Standards Take Effect
2000: Tier 2 standards set; cars and light trucks now held to same standards
2004: Tier 2 Standards Fully Take Effect
2014: Tier 3 standards set
2017: Tier 3 Standards begin phase-in
2025: Tier 3 Standards Fully Take Effect