Sulfur naturally occurs in gasoline and diesel fuel, contributing to pollution when the fuel is burned. Beginning in 2004, standards were set on the amount of sulfur in gasoline (Tier 2 standards). Separate standards were set for different entities, such as large refiners, small refiners, importers, downstream wholesalers, etc. In March 2014, Tier 3 standards were finalized by the Environmental Protection Agency (EPA). Tier 3 standards take effect in 2017. Large refinery standards are shown below, both the maximum and average per gallon. See the Environmental Protection Agency website for additional details on sulfur standards.

EPA Gasoline Sulfur Standards, 2004-On


Note: N/A = not applicable.

Supporting Information

EPA Gasoline Sulfur Standards, 2004-On
 Sulfur Standards
(Parts per Million)
Per Gallon Maximum3003008080
Per Gallon AverageN/A303010
U.S. Environmental Protection Agency Tier 2 Vehicle and Gasoline Sulfur Program and Tier 3 Vehicle Emission and Fuel Standards Program

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