No trucks classified as one-ton vehicles or
over, semitrailers or tractors, unattached camping or house
trailers, implement trailers, or similar vehicles shall be
permitted to park on any public street, thoroughfare, public
alley, parking lot or public property for a period longer than
two (2) hours, except where such vehicle is parked on a street
or thoroughfare on which the adjacent property on both sides of
the street or thoroughfare is zoned for light industry (LI) or
heavy industry (HI). This restriction shall not apply to
vehicles actually engaged in moving household furniture or
furnishings, small delivery trucks, service trucks, or service
trailers, however, each vehicle or trailer exempted in this
section shall be subject to section 15-50.