It shall be the duty of any person or persons engaged in digging into any street, alley or other public highway, in paving any street or alley, building of any sewer or drain, or trench for water pipes or gas pipes in any of the public alleys, avenues or other public places, under contract with the city, or by virtue of any permission which may have been granted to them by the council, or the superintendent of streets or city engineer, where such work, if left exposed, would be dangerous to passengers, to erect a fence or railing at such excavation or work in such a manner as to prevent danger to passengers who may be traveling in streets, alleys, avenues or public places, and to continue the said railing or fence until the work shall be completed or the obstruction or danger removed. And it shall be the duty of such persons to place upon such railing, fence, barrier or other obstruction at twilight in the evening, suitable and sufficient light, and keep them burning through the night during the performance of said work, under a penalty of not less than twenty five dollars ($25.00) nor more than five hundred dollars ($500.00) for every such neglect. (Ord. 872, 2-17-1981)