(A) Building materials shall not be laid on any sidewalk, street or public place unless official permission is first obtained. It shall be the duty of the person desiring so to use the streets thusly to obtain permission to lay such material thereon, and otherwise to obstruct such places for the purpose of erecting a building adjoining said street, where some obstruction thereof is necessary, to estimate what space will be needed and for what length of time the obstruction will be necessary. Official permission may be given accordingly, imposing then and from time to time such reasonable conditions as may be considered necessary or proper for the protection of the public and public property.
('86 Code, § 15.216)
(B) While the obstructions provided for in this chapter remain on the streets, sidewalks or other public places suitable safeguard by day and by night shall be maintained by the contractor, owner or person in charge of the work, for the protection of the public by roping off using lanterns and other proper means.
('86 Code, § 15.217) Penalty, see § 10.99