Texas Agriculture Code - AGRIC § 163.021. Classification of Areas

(a) The commission by rule may prescribe criteria for classifying areas in the state for purposes of brucellosis control.  The commission may prescribe differing control measures and procedures according to the classification of the areas.  The classifications shall be based on criteria that use sound epidemiological principles and are similar to the criteria provided by federal brucellosis control regulations.

(b) The commission by rule may designate as a particular classification any area consisting of one county or two or more contiguous counties.  The designation of an area for state purposes need not be the same as the designation of the area for federal purposes.