543.11 TRAFFIC NOISE.
   No vehicle operating either on the public right of way or on private property shall exceed the maximum sound pressure level of eighty decibels dB(A), except that for vehicles over a gross volume weight of 8,000 pounds on a state highway or a prescribed truck route, or in commercial or industrial zones that are not adjacent to a residential zone, the maximum sound pressure level shall not exceed eighty-eight decibels dB(A).
(1964 Code Sec. 99.11)