For the purposes of this chapter, the existence of the following condition is declared to constitute a noise hazard:

The persistent maintenance or emission of any noise or sound produced by human, animal or mechanical means between the hours of nine p.m. and seven a.m., or by any animal at any time which, by reason of its obnoxious, excessive, unnecessary or unreasonable nature, shall disturb the peace or comfort, or be injurious to the health of any person or persons; provided, however, any private person proposing to engage in any construction project using machine-powered equipment shall apply to the Director of Public Works for a permit therefor. In issuing the permit, the Director may impose such conditions as may be reasonable to avoid obnoxious noise emissions and otherwise reduce obnoxious noise levels. (Ord. 4883-NS § 1 Exhibit A, Ch. 8 § 4, 1976)