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Gasoline Standards

Reformulated Gasoline

Reformulated gasoline (RFG) is gasoline blended to burn more cleanly than conventional gasoline and to reduce smog-forming and toxic pollutants in the air we breathe. The RFG program was mandated by Congress in the 1990 Clean Air Act amendments. The first phase of the RFG program began in 1995 and the second (current) phase began in 2000.

RFG is required in cities with high smog levels and is optional elsewhere. RFG is currently used in 17 states and the District of Columbia. About 25 percent of gasoline sold in the U.S. is reformulated.

The air quality benefits RFG has achieved represent a significant part of the country's smog reduction strategy. The RFG program, combined with other industrial and transportation controls aimed at smog reduction, is contributing to the long-term downward trend in U.S. smog levels. About 75 million people breathe cleaner air because of RFG.

The Fuel Streamlining rule, which was finalized on December 4, 2020 (See 85 FR 78412.) simplified the RFG summer volatile organic compound (VOC) standards by establishing a 7.4 psi RVP standard for RFG. The final rule also updated the RFG opt-out procedures by eliminating outdated regulatory text and establishing a process that mandatory RFG areas can use to opt-out of the requirement if they meet the specified criteria.More information is available on the Fuels Regulatory Streamlining webpage.

Phase II Reformulated Gasoline: The Next Major Step Toward Cleaner Air (PDF) (2 pp, 152 K, EPA-420-F-99-042, November 1999, About PDF)

Learn more about RFG federal standards.

The tables below list the RFG covered areas including the counties and independent cities in each area and descriptions of any partial counties in the RFG area.

The nine RFG covered areas required by 42 U.S.C. 7545(k)(10)(D) to implement RFG:

Area Designation

State

Counties

Independent Cities

Los Angeles-Anaheim-Riverside

California

Los Angeles, Orange, Ventura, San Bernardino,1 Riverside2

San Diego County

California

San Diego

Greater Connecticut

Connecticut

Hartford, Middlesex, New Haven, New London, Tolland, Windham, Fairfield (only the City of Shelton), Litchfield (all except the towns of Bridgewater and New Milford)

New York-Northern New Jersey-Long Island-Connecticut

Connecticut

Fairfield (all except the City of Shelton), Litchfield (only the towns of Bridgewater and New Milford)

New Jersey

Bergen, Essex, Hudson, Hunterdon, Middlesex, Monmouth, Morris, Ocean, Passaic, Somerset, Sussex, Union

New York

Bronx, Kings, Nassau, New York, Orange, Putnam, Queens, Richmond, Rockland, Suffolk, Westchester

Philadelphia-Wilmington-Trenton

Delaware

Kent, New Castle

Maryland

Cecil

New Jersey

Burlington, Camden, Cumberland, Gloucester, Mercer, Salem

Pennsylvania

Bucks, Chester, Delaware, Montgomery, Philadelphia

Chicago-Gary-Lake County

Illinois

Cook, Du Page, Kane, Lake, McHenry, Will, Grundy (only Aux Sable Township and Goose Lake Township), Kendall (only Oswego Township)

Indiana

Lake, Porter

Baltimore

Maryland

Anne Arundel, Baltimore, Carroll, Harford, Howard

Baltimore

Houston-Galveston-Brazoria

Texas

Brazoria, Chambers, Fort Bend, Galveston, Harris, Liberty, Montgomery, Waller

Milwaukee-Racine

Wisconsin

Kenosha, Milwaukee, Ozaukee, Racine, Washington, Waukesha

1 That portion of San Bernardino County, CA that lies south of latitude 35 degrees, 10 minutes north and west of longitude 115 degrees, 45 minutes west. 

2That portion of Riverside County, CA that lies to the west of a line described as follows: beginning at the northeast corner of Section 4, Township 2 South, Range 5 East, a point on the boundary line common to Riverside and San Bernardino Counties; then southerly along section lines to the centerline of the Colorado River Aqueduct; then southeasterly along the centerline of said Colorado River Aqueduct to the southerly line of Section 36, Township 3 South, Range 7 East; then easterly along the township line to the northeast corner of Section 6, Township 4 South, Range 9 East; then southerly along the easterly line of Section 6 to the southeast corner thereof; then easterly along section lines to the northeast corner of Section 10, Township 4 South, Range 9 East; then southerly along section lines to the southeast corner of Section 15, Township 4 South, Range 9 East; then easterly along the section lines to the northeast corner of Section 21, Township 4 South, Range 10 East; then southerly along the easterly line of Section 21 to the southeast corner thereof; then easterly along the northerly line of Section 27 to the northeast corner thereof; then southerly along section lines to the southeast corner of Section 34, Township 4 South, Range 10 East; then easterly along the township line to the northeast corner of Section 2, Township 5 South, Range 10 East; then southerly along the easterly line of Section 2, to the southeast corner thereof; then easterly along the northerly line of Section 12 to the northeast corner thereof; then southerly along the range line to the southwest corner of Section 18, Township 5 South, Range 11 East; then easterly along section lines to the northeast corner of Section 24, Township 5 South, Range 11 East; and then southerly along the range line to the southeast corner of Section 36, Township 8 South, Range 11 East, a point on the boundary line common to Riverside and San Diego Counties.

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RFG covered areas based on being reclassified as Severe ozone nonattainment areas under 42 U.S.C. 7511(b):

Area Designation

State or District

Counties

Independent Cities

Washington, DC-Maryland-Virginia

District of Columbia

Washington

Maryland

Calvert, Charles, Frederick, Montgomery, Prince George’s

Virginia

Arlington, Fairfax, Loudoun, Prince William, Stafford

Alexandria, Fairfax, Falls Church, Manassas, Manassas Park

Sacramento Metro

California

Sacramento, Yolo, El Dorado (except Lake Tahoe and its drainage area), Placer,1 Solano,2 Sutter3

San Joaquin Valley

California

Fresno, Kings, Madera, Merced, San Joaquin, Stanislaus, Tulare, Kern4

1All portions of Placer County except that portion of the County within the drainage area naturally tributary to Lake Tahoe including said Lake, plus that area in the vicinity of the head of the Truckee River described as follows: commencing at the point common to the aforementioned drainage area crestline and the line common to Townships 15 North and 16 North, Mount Diablo Base and Meridian (M.D.B.& M.), and following that line in a westerly direction to the northwest corner of Section 3, Township 15 North, Range 16 East, M.D.B.& M., thence south along the west line of Sections 3 and 10, Township 15 North, Range 16 East, M.D.B.& M., to the intersection with the said drainage area crestline, thence following the said drainage area boundary in a southeasterly, then northeasterly direction to and along the Lake Tahoe Dam, thence following the said drainage area crestline in a northeasterly, then northwesterly direction to the point of beginning.

2That portion of Solano County that lies north and east of a line described as follows: beginning at the intersection of the westerly boundary of Solano County and the 1/4 section line running east and west through the center of Section 34; T. 6 N., R. 2 W., M.D.B.& M.; thence east along said 1/4 section line to the east boundary of Section 36, T. 6 N., R. 2 W.; thence south 1/2 mile and east 2.0 miles, more or less, along the west and south boundary of Los Putos Rancho to the northwest corner of Section 4, T. 5 N., R. 1 W.; thence east along a line common to T. 5 N. and T. 6 N. to the northeast corner of Section 3, T. 5 N., R. 1 E.; thence south along section lines to the southeast corner of Section 10, T. 3 N., R. 1 E.; thence east along section lines to the south 1/4 corner of Section 8, T. 3 N., R. 2 E.; thence east to the boundary between Solano and Sacramento Counties.

3That portion of Sutter County south of a line connecting the northern border of Yolo Co. to the SW tip of Yuba Co. and continuing along the southern Yuba Co. border to Placer Co. 

4Boundary between the Kern County and San Joaquin Valley air districts that generally follows the ridge line of the Sierra Nevada and Tehachapi Mountain Ranges. That portion of Kern County that lies west and north of a line described as follows: beginning at the Kern-Los Angeles County boundary and running north and east along the northwest boundary of the Rancho La Liebre Land Grant to the point of intersection with the range line common to Range 16 West and Range 17 West, San Bernardino Base and Meridian; north along the range line to the point of intersection with the Rancho El Tejon Land Grant boundary; then southeast, northeast, and northwest along the boundary of the Rancho El Tejon Grant to the northwest corner of Section 3, Township 11 North, Range 17 West; then west 1.2 miles; then north to the Rancho El Tejon Land Grant boundary; then northwest along the Rancho El Tejon line to the southeast corner of Section 34, Township 32 South, Range 30 East, Mount Diablo Base and Meridian; then north to the northwest corner of Section 35, Township 31 South, Range 30 East; then northeast along the boundary of the Rancho El Tejon Land Grant to the southwest corner of Section 18, Township 31 South, Range 31 East; then east to the southeast corner of Section 13, Township 31 South, Range 31 East; then north along the range line common to Range 31 East and Range 32 East, Mount Diablo Base and Meridian, to the northwest corner of Section 6, Township 29 South, Range 32 East; then east to the southwest corner of Section 31, Township 28 South, Range 32 East; then north along the range line common to Range 31 East and Range 32 East to the northwest corner of Section 6, Township 28 South, Range 32 East; then west to the southeast corner of Section 36, Township 27 South, Range 31 East; then north along the range line common to Range 31 East and Range 32 East to the Kern-Tulare County boundary.

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RFG covered areas based on being classified ozone nonattainment areas at the time that the state requested to opt into RFG under 42 U.S.C. 7545(k)(6)(A)(i):

Area Designation at the Time of Opt-in

State

Counties

Independent Cities

Sussex County

Delaware

Sussex

St. Louis, Missouri-Illinois

Illinois

Jersey, Madison, Monroe, St. Clair

Missouri

Franklin, Jefferson, St. Charles, St. Louis

St. Louis

Kentucky portion of Louisville

Kentucky

Jefferson, Bullitt,1 Oldham2

Kent and Queen Anne’s Counties

Maryland

Kent, Queen Anne’s

Statewide

Massachusetts

All

Strafford, Merrimack, Hillsborough, Rockingham Counties

New Hampshire

Hillsborough, Merrimack, Rockingham, Strafford

Atlantic City

New Jersey

Atlantic, Cape May

New Jersey portion of Allentown- Bethlehem-Easton

New Jersey

Warren

Dutchess County

New York

Dutchess

Essex County

New York

Essex (the portion of Whiteface Mountain above 4,500 feet in elevation)

Statewide

Rhode Island

All

Dallas-Fort Worth

Texas

Collin, Dallas, Denton, Tarrant

Norfolk-Virginia Beach, Newport News (Hampton Roads)

Virginia

James City, York

Chesapeake, Hampton, Newport News, Norfolk, Poquoson, Portsmouth, Suffolk, Virginia Beach, Williamsburg

Richmond

Virginia

Charles City, Chesterfield, Hanover, Henrico

Colonial Heights, Hopewell, Richmond

1In Bullitt County, KY, beginning at the intersection of Ky 1020 and the Jefferson-Bullitt County Line proceeding to the east along the county line to the intersection of county road 567 and the Jefferson-Bullitt County Line; proceeding south on county road 567 to the junction with Ky 1116 (also known as Zoneton Road); proceeding to the south on KY 1116 to the junction with Hebron Lane; proceeding to the south on Hebron Lane to Cedar Creek; proceeding south on Cedar Creek to the confluence of Floyds Fork turning southeast along a creek that meets Ky 44 at Stallings Cemetery; proceeding west along Ky 44 to the eastern most point in the Shepherdsville city limits; proceeding south along the Shepherdsville city limits to the Salt River and west to a point across the river from Mooney Lane; proceeding south along Mooney Lane to the junction of Ky 480; proceeding west on Ky 480 to the junction with Ky 2237; proceeding south on Ky 2237 to the junction with Ky 61 and proceeding north on Ky 61 to the junction with Ky 1494; proceeding south on Ky 1494 to the junction with the perimeter of the Fort Knox Military Reservation; proceeding north along the military reservation perimeter to Castleman Branch Road; proceeding north on Castleman Branch Road to Ky 44; proceeding a very short distance west on Ky 44 to a junction with Ky 1020 and proceeding north on Ky 1020 to the beginning.

2In Oldham County, KY, beginning at the intersection of the Oldham-Jefferson County Line with the southbound lane of Interstate 71; proceeding to the northeast along the southbound lane of Interstate 71 to the intersection of Ky 329 and the southbound lane of Interstate 71; proceeding to the northwest on Ky 329 to the intersection of Zaring Road on Ky 329; proceeding to the east-northeast on Zaring Road to the junction of Cedar Point Road and Zaring Road; proceeding to the north-northeast on Cedar Point Road to the junction of Ky 393 and Cedar Point Road; proceeding to the south-southeast on Ky 393 to the junction of county road 746 (the road on the north side of Reformatory Lake and the Reformatory); proceeding to the east-northeast on county road 746 to the junction with Dawkins Lane (also known as Saddlers Mill Road) and county road 746; Proceeding to follow an electric power line east-northeast across from the junction of county road 746 and Dawkins Lane to the east-northeast across Ky 53 on to the La Grange Water Filtration Plant; proceeding on to the east-southeast along the power line then south across Fort Pickens Road to a power substation on Ky 146; proceeding along the power line south across Ky 146 and the Seaboard System Railroad track to adjoin the incorporated city limits of La Grange; then proceeding east then south along the La Grange city limits to a point abutting the north side of Ky 712; proceeding east-southeast on Ky 712 to the junction of Massie School Road and Ky 712; proceeding to the south-southwest and then north-northwest on Massie School Road to the junction of Ky 53 and Massie School Road; proceeding on Ky 53 to the north-northwest to the junction of Moody Lane and Ky 53; proceeding on Moody Lane to the south-southwest until meeting the city limits of La Grange; then briefly proceeding north following the La Grange city limits to the intersection of the northbound lane of Interstate 71 and the La Grange city limits; proceeding southwest on the northbound lane of Interstate 71 until intersecting with the North Fork of Currys Fork; proceeding south-southwest beyond the confluence of Currys Fork to the south-southwest beyond the confluence of Floyds Fork continuing on to the Oldham-Jefferson County Line and proceeding northwest along the Oldham-Jefferson County Line to the beginning.

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RFG covered area that is located in the ozone transport region established by 42 U.S.C. 7511c(a) that a state requested to opt into RFG under 42 U.S.C. 7545(k)(6)(B)(i)(I):

State

Counties

Maine

Androscoggin, Cumberland, Kennebec, Knox, Lincoln, Sagadahoc, York

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A note about areas in California:

All counties implement a version of the California Reformulated Gasoline Program, not just those listed here as Clean Air Act-required areas. Standards differ from federal RFG requirements, and compliance periods vary by air basin. Please refer to the California Air Resources Board website for additional details: https://www.arb.ca.gov/fuels/fuels.htmExit

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"Opt-Out" Areas:
Arizona
Phoenix, AZ nonattainment area
Maricopa County (partial)
  • Phoenix opted in the RFG program in 1997; retail stations were
    required to supply RFG by August 4, 1997
  • In September 1997, the Governor of Arizona submitted an RFG
    opt-out petition for purposes of adopting a more stringent state
    RFG program in Phoenix.
  • EPA approved the opt-out petition which became effective on June
    10, 1998.
Kentucky

Kentucky portion of the Cincinnati-Hamilton, Ohio-Kentucky-Indiana maintenance area for the 2008 ozone NAAQS (Northern Kentucky Area)
Boone County
Campbell County
Kenton County

Kentucky voluntarily opted in the federal RFG program (for the Northern Kentucky Area) in 1995.

In April 2017, the Secretary for Kentucky’s Energy and Environment Cabinet submitted an RFG opt-out petition.

EPA approved the opt-out petition which became effective on July 1, 2018.
Maine
 Androscoggin County
Cumberland County
Hancock County
Kennebec County
Knox County
Lincoln County
Sagadahoc County
Waldo County
York County
These "Opt-Out" areas withdrew from the federal RFG program before it went into effect on January 1, 1995. However, on January 23, 2015, the Administrator signed a final rule approving Maine’s request that seven of these counties (Androscoggin, Cumberland, Kennebec, Knox, Lincoln, Sagadahoc, and York counties) opt into the RFG program beginning on May 1, 2015.
New York

Albany County
Erie County
Greene County
Jefferson County
Montgomery County
Niagara County
Rensselear County
Saratoga County
Schenectady County

A proposed rule to remove the above "opt-out" areas from the requirements of the reformulated gasoline program was published June 14, 1995. [On January 1, 1995, a temporary exemption of the RFG requirements in these areas went into effect. On July 1, 1995 this stay was extended until the Agency took final action].

The final rule, published July 8, 1996 [61 FR 35673], formally removed these areas from the list of RFG covered areas and provided states with general opt-out procedures.

The July 8 final rule was superseded by a final rule published October 20, 1997 [62 FR 54552], revising the opt-out procedures.
Pennsylvania
Adams County
Allegheny County
Armstrong County
Beaver County
Berks County
Blair County
Butler County
Cambria County
Carbon County
Columbia County
Cumberland County
Dauphin County
Erie County
Fayette County
Lackawanna County
Lancaster County
Lebanon County
Lehigh County
Luzerne County
Mercer, PA
Monroe County
Northampton County
Perry County
Somerset County
Washington County
Westmoreland County
Wyoming County
York County

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