It shall be unlawful for the operator of any vehicle to park or stop such vehicle for any purpose other than the loading or unloading of passengers or materials; provided, however, no stop for the loading of passengers shall be made for more than three (3) minutes nor for the loading or unloading of materials for more than twenty (20) minutes in any of the following places:
(a) In any alley within any business or residence district; and
(b) In any loading zone designated by the City Engineer; provided, however, such loading zone shall be designated by yellow painted curb markings or signs.
(§ 7142, 7142.1, and 7142.2, T.O.O.C., as amended by § I, Ord. 489-NS, eff. August 22, 1974, and § I, Ord. 538-NS, eff. August 21, 1975)