Tennessee Code Title 54. Highways, Bridges and Ferries § 54-1-129

(a) Notwithstanding any law to the contrary, it is the duty of the department of transportation to erect and maintain informational signs at sites and facilities that serve the educational, historical and cultural interests of the citizens of the state, including the erection and maintenance of the signs along the various highways of Tennessee for radio stations that regularly broadcast public service information regarding weather conditions, travel and road conditions and/or tourism-related sites and facilities in their respective areas. In order to be eligible for the highway signage, radio stations shall demonstrate that no less than one-fourth ( 1/4 ) of their total broadcast programming consists of public service information regarding weather conditions, travel and road conditions and/or tourism-related sites and facilities in their respective areas, and that the public service information is broadcast regularly at intervals of no greater than thirty (30) minutes during the period of time the radio station is on the air.

(b) The department shall promulgate rules and regulations, within the specific parameters of subsection (a), to establish eligibility standards for the erection of highway signs for radio stations broadcasting public service information.

(c) Erection of the informational signs shall be within the guidelines prescribed by the Manual on Uniform Traffic Control Devices.

(d) This section shall become operative only if the federal highway administrator advises the commissioner of transportation in writing that this section shall not render Tennessee in violation of federal laws and regulations and subject to penalties prescribed in the federal laws and regulations.