Every person shall enclose with sufficient barriers each installation of sidewalk, driveway, curb and gutter under construction in the streets or public ways of the city. All machinery and equipment shall be locked or otherwise effectively safeguarded from unauthorized use when not being used by the permittee, his agents or employees. Red lights or torch lamps shall be kept burning from sunset to sunrise, one red light or torch lamp to be placed at each end of the openings in the street or way and other lights sufficient in number and properly spaced to give adequate warning. (1975 Code Ch. 6 § IV)