All persons loading or unloading goods at any business house or establishment in a business district having accessible back or side entrances shall use such back or side entrances for the purpose of loading or unloading goods, and in all cases where there exists an accessible back or side entrance it shall be unlawful to load or unload goods across any sidewalk of the principal business streets of the municipality, unless otherwise authorized by a special permit issued in the discretion of the Chief of Police.
('81 Code, § 72.16) Penalty, see § 70.99