e/United States emission standards

Information
has gloss	eng: Light-duty vehicles Two sets, or Tiers, of emission standards for light-duty vehicles in the United States were defined as a result of the Clean Air Act Amendments of 1990. The Tier I standard was adopted in 1991 and was phased in from 1994 to 1997. Tier II standards are being phased in from 2004 to 2009.
lexicalization	eng: United States emission standards
instance of	c/Emission standards