Code of Federal Regulations Title 47. Telecommunication § 47.73.609 Zones

(1) Zone I consists of that portion of the United States located within the confines of the following lines drawn on the U.S. Albers Equal Area Projection Map (based on standard parallels 29 1/2 ° and 45 1/2 °;  North American datum):  Beginning at the most easterly point on the State boundary line between North Carolina and Virginia;  thence in a straight line to a point on the Virginia–West Virginia boundary line located at north latitude 37°49′ and west longitude 80°12′30″;  thence westerly along the southern boundary lines of the States of West Virginia, Ohio, Indiana, and Illinois to a point at the junction of the Illinois, Kentucky, and Missouri State boundary lines;  thence northerly along the western boundary line of the State of Illinois to a point at the junction of the Illinois, Iowa, and Wisconsin State boundary lines;  thence easterly along the northern State boundary line of Illinois to the 90th meridian;  thence north along this meridian to the 43.5° parallel;  thence east along this parallel to the United States–Canada border;  thence southerly and following that border until it again intersects the 43.5° parallel;  thence east along this parallel to the 71st meridian;  thence in a straight line to the intersection of the 69th meridian and the 45th parallel;  thence east along the 45th parallel to the Atlantic Ocean. When any of the above lines pass through a city, the city shall be considered to be located in Zone I. (See Figure 1 of § 73.699.)

(2) Zone II consists of that portion of the United States which is not located in either Zone I or Zone III, and Puerto Rico, Alaska, Hawaiian Islands and the Virgin Islands.

(3) Zone III consists of that portion of the United States located south of a line, drawn on the United States Albers Equal Area Projection Map (based on standard parallels 29.50 and 45.50 North American datum), beginning at a point on the east coast of Georgia and the 31st parallel and ending at the United States–Mexican border, consisting of arcs drawn with a 241.4 kilometer (150 mile) radius to the north from the following specified points: