A. Subject to other and more restrictive limitations, a vehicle may be stopped or parked within 18 inches of the curb facing in the direction of traffic movement upon any one-way street unless signs are in place prohibiting such stopping or standing.

B. In the event a highway includes two or more separate roadways and traffic is restricted to one direction upon any such roadway, no person shall stand or park a vehicle upon the left-hand side of such one-way roadway unless signs are in place permitting such standing or parking.

C. The City Traffic Engineer is authorized to determine when standing or parking shall be prohibited upon the left-hand side of any one-way street or when standing or parking may be permitted upon the left-hand side of any one-way roadway of a highway having two or more separate roadways and shall erect signs giving notice thereof.

D. The requirements of parallel parking imposed by this section shall not apply in the event any commercial vehicle is actually engaged in the process of loading or unloading freight or goods, in which case such vehicle may be backed up to the curb; provided, that such vehicle does not extend beyond the centerline of the street and does not block traffic thereby.