The Steubenville-Weirton-Wheeling Interstate Air Quality Control Region (Ohio-West Virginia) consists of the territorial area encompassed by the boundaries of the following jurisdictions or described area (including the territorial area of all municipalities (as defined in section 302(f) of the Clean Air Act, 42 U.S.C. 1857h(f)) geographically located within the outermost boundaries of the area so delimited):
In the State of Ohio: Belmont County, Columbiana County, Jefferson County, Monroe County.
In the State of West Virginia: Brooke County, Hancock County, Marshall County, Ohio County.