A.    Emergency Exception. The provisions of this chapter shall not apply to:

    1.    The emission of sound for the purpose of alerting persons to existence of an emergency; or

    2.    The emission of sound in the performance of emergency work.

    B.    Warning Devices. Warning devices, necessary for the protection of public safety as, for example, police, fire and ambulance sirens and train horns shall be exempted from the provisions of this chapter.

    C.    Federal or State Preempted Activities. The provisions of this chapter shall not apply to any other activity to the extent regulation thereof has been preempted by state or federal law.

    D.    Public Health, Welfare and Safety Activities. The provisions of this chapter shall not apply to construction or maintenance and repair operations conducted by public agencies and/or utility companies or their contractors which are deemed necessary to serve the best interests of the public and to protect the public health, welfare and safety, including, but not limited to street sweeping, debris and limb removal, removal of downed wires, restoring electrical service, repairing traffic signals, unplugging sewers, vacuuming catch basins, repairing of water hydrants and mains, gas lines, oil lines, sewers, storm drains, roads, sidewalks, etc.

    E.    Construction. The provisions of this chapter shall not apply to noise sources associated with construction, provided said activities do not take place before seven a.m. or after seven p.m. on any day except Saturday or Sunday, or before eight a.m. or after five p.m. on Saturday or Sunday.

    F.    Maintenance of Residential Property. The provisions of this chapter shall not apply to noise sources associated with the maintenance of residential property provided said activities take place between the hours of seven a.m. and nine p.m. on any day except Saturday or Sunday, or between the hours of nine a.m. and eight p.m. on Saturday or Sunday.

    G.    Proviso. Notwithstanding the provisions of subsections D, E and F of this section, no exemptions from the provisions at this chapter shall be granted for activities specified in said sections where equipment used for those activities, including mufflers, is not maintained in the condition for which it was designed or intended and thereby unnecessarily increases noise levels so as to cause a noise disturbance or exceed the standards set forth in Section 6.60.040 of this chapter. (Prior gen. code §§ 3-107.701— 3-107.707)