Any person obtaining a permit to occupy any street, alley or sidewalk with any obstruction shall exhibit a red light at night in such a manner as to warn the public of the obstruction. Such light shall be exhibited so as to show distinctly the clear passageway left in the roadway or sidewalk. When the space occupied by the obstruction extends for twenty or more feet along a curb or lengthwise along the street or sidewalk, one red light shall be exhibited at each end of the obstruction, hung clear of the obstruction on the side adjoining the passageway.
(1970 Code Sec. 28-7)