Tennessee Code Title 68. Health, Safety and Environmental Protection § 68-2-702

(a) There may be created for the health district so formed, a joint district board of health consisting of the county mayor, the county director of schools, and one (1) physician, licensed to practice in Tennessee from each county of the district. The physician member from each county shall be nominated by the medical society and elected by the county legislative body of the county in which the physician member resides. In counties operating under a county council or commission form of government, the chair of the county council or commission shall serve as a member of the district board of health.

(b) A district board of health shall be considered duly constituted and empowered as soon as the several physician members from the respective counties have been elected by the respective county legislative bodies.