§ 8-46.  Exempt noises.
   The following are exempt from the provisions of sections 8-41, 8-43 and 8-44:
      (1)   Lawn mowers, yard equipment and agriculture equipment during daylight hours (7:00 a.m. to 10:00 p.m.) when operated with all the manufacturer's standard mufflers and noise-reducing equipment in use and proper operating condition.
      (2)   Nonamplified crowd noises resulting from activities such as those planned by student, governmental or community groups.
      (3)   Construction operations for which building permits have been issued or construction operations not requiring permits due to ownership of the project by an agency of government; providing all equipment is operated in accord with the manufacturer's specifications and with all standard equipment, manufacturer's mufflers and noise-reducing equipment in use and in proper operating condition.  Such construction shall not begin prior to 7:00 a.m. and shall cease by 7:00 p.m. unless a special permit has been granted by the noise control officer or the city.
      (4)   Noises of safety signals, warning devices, emergency pressure relief valves, and bells and chimes of churches.  This exemption shall not nullify section 8-44(12).
      (5)   Noises resulting from any authorized emergency vehicle when responding to an emergency call or acting in time of emergency.
      (6)   Any other noise resulting from activities of a temporary duration permitted by law and for which a license or permit therefor has been granted by the NCO or the city in accordance with this article.  Regulation of noises emanating from operations under permit shall be according to the conditions and limits stated on the permit and in the sections or subsections of this article authorizing the issuance of the permit.
      (7)   Noises made by persons having obtained a permit to use the streets or other public space.
      (8)   All noises coming from the normal operations of aircraft (not including model aircraft) and aircraft ground testing operations between 8:00 a.m. and 8:00 p.m. Monday through Saturday and only on Sunday from 12:00 noon to 5:00 p.m.
      (9)   Any noise, including but not limited to, noise relating to the operation of trains, regulation of which is preempted by the federal government, but only to the extent of such federal preemption.
(Ord. No. 1454, § 6, 2-11-91)