Except when authorized by a written permit from the traffic engineer, no person shall operate the following vehicles in the central traffic district between the hours of 9:00 A.M. and 6:00 P.M. of any day:
(1) A freight vehicle more than eight and one-half feet in width, with load, or so loaded that any part of its load extends more than twenty feet to the front or rear of said vehicle;
(2) A vehicle carrying building material that has not been loaded or is not to be unloaded at some point within the central traffic district;
(3) A vehicle conveying refuse, garbage, wet garbage, or dirt. (Ord. No. 938, §1.)