Where any portion of a turnpike is a properly marked toll booth zone, as indicated with appropriate signs placed in accordance with the latest edition of the Manual on Uniform Traffic Control Devices, and a reduced speed limit, as properly posted shall be in effect within the zone, no person shall drive any vehicle upon that portion of the turnpike which is the toll booth zone in excess of the reduced speed limit so posted. Violation of the posted reduced speed limit in the toll booth zone shall result in the doubling of the appropriate fine.
Okla. Stat. tit. 47, § 11-806.2