"Coming Soon: U.S. Tier 3 Emissions and Fuel Standards"
"WASHINGTON, DC -- Sometime before the end of March, the U.S. Environmental Protection Agency is expected to propose new national vehicle emissions and fuel standards by updating a program called Tier 3. Updated Tier 3 standards would cut smog and soot, among other pollutants, by establishing new standards for light-duty vehicles and their fuels to reduce emissions of the most toxic pollutants."