1020.07   WARNING LIGHTS AND BARRICADES.
   (A)   Whoever makes or causes to be made any excavation in or adjoining any street or public ground and whoever occupies or causes to be occupied any
portion of any street with any building material or obstruction shall provide sufficient warning lights and barricades, as required herein, to adequately protect pedestrian and vehicular traffic.
   (B)   Not less than two warning lights shall be secured and conspicuously posted in or near such excavation, building material or obstruction, one or more at each end of the space so excavated or occupied. If the space occupied by such obstruction exceeds ten feet in length, then additional lights shall be posted as aforesaid for every additional ten feet in length so excavated or occupied. Such lights shall be lighted during the hours of darkness and at any time when ordinary visibility is obscured. The City Engineer or any Assistant City Engineer may, at his discretion, require additional lights in the case of any excavated area.
   (C)   In the case of excavations, whether in or adjoining a street or public ground, and in the case of other open or exposed places within the City, suitable warning barriers shall be set up to protect against accidents.
(1956 Code Sec. 301.07)