(a) 
In order to control unnecessary, excessive and annoying sounds emanating from incorporated areas of the city, it is declared to be the policy of the city to prohibit such sounds generated from all sources as specified in this chapter.
(b) 
It is determined that certain noise levels are detrimental to the public health, welfare and safety and contrary to public interest; therefore, the city council does ordain and declare that creating, maintaining, causing or allowing to create, maintain or cause any noise in a manner prohibited by or not in conformity with the provisions of this chapter, is a public nuisance and shall be punishable as such.
(Ord. 806 § 2, 1976)
The following words, phrases and terms as used in this chapter shall have the meaning as indicated below:
"Ambient noise level"
means the all-encompassing noise level associated with a given environment, being a composite of sounds from all sources, excluding the alleged offensive noise, at the location and approximate time at which a comparison with the alleged offensive noise is to be made.
"Cumulative period"
means an additive period of time composed of individual time segments which may be continuous or interrupted.
"Decibel" (dB)
means a unit which denotes the ratio between two quantities which are proportional to power; the number of decibels corresponding to the ratio of two amounts of power is ten times the logarithm to the base ten of this ratio.
"Dwelling unit"
means a single unit providing complete, independent living facilities for one or more persons including permanent provisions for living, sleeping, eating, cooking and sanitation.
"Emergency machinery, vehicle or work"
means any machinery, vehicle or work used, employed or performed in an effort to protect. provide or restore safe conditions in the community or for the citizenry, or work by private or public utilities when restoring utility service.
"Fixed noise source"
means a stationary device which creates sounds while fixed or motionless including but not limited to industrial and commercial machinery and equipment, pumps, fans, compressors, generators, air conditioners and refrigerator equipment.
"Grading"
means any excavating or filling of earth material, or any combination thereof, conducted at a site to prepare said site for construction or other improvements thereon.
"Impact noise"
means the noise produced by the collision of one mass in motion with a second mass which may be either in motion or at rest.
"Mobile noise source"
means any noise source other than a fixed noise source.
"Noise level"
means the "A" weighted sound pressure level in decibels obtained by using a sound level meter at slow response with a reference pressure of twenty microNewtons per square meter. The unit of measurement shall be designated as dB(A).
"Noise variance board"
means an administrative board of five members appointed by the board of supervisors of the county, per Title 4, Division 6, Article 1 of the codified ordinances of the county.
"Person"
means a person, firm, association, copartnership, joint venture, corporation or any entity, public or private in nature.
"Residential property"
means a parcel of real property which is developed and used either in part or in whole for residential purposes, other than transient uses such as hotels and motels.
"Simple tone noise"
means a noise characterized by a predominant frequency or frequencies so that other frequencies cannot be readily distinguished.
"Sound level meter"
means an instrument meeting American National Standard Institute's Standard S1.4-1971 for Type 1 or Type 2 sound level meters or an instrument and the associated recording and analyzing equipment which will provide equivalent data.
"Sound pressure level"
of a sound, in decibels, means twenty times the logarithm to the base ten of the ratio of the pressure of the sound to a referenced pressure, which reference pressure shall be explicitly stated.
(Ord. 806 § 2, 1976)
The residential properties hereinafter described are assigned to the following noise zones:
Noise Zone 1: All properties located in residential zone districts.
(Ord. 806 § 2, 1976)
(a) 
The following noise standards, unless otherwise specifically indicated, shall apply to all residential property within a designated noise zone:
Noise Standards
Noise Zone
Noise Level
Time Period
1
55 dB(A)
7 a.m. — 10 p.m.
50 dB(A)
10 p.m. — 7 a.m.
In the event the alleged offensive noise consists entirely of impact noise, simple tone noise, speech, music, or any combination thereof, each of the above noise levels shall be reduced by 5 dB(A).
(b) 
It is unlawful for any person at any location within the city to create any noise, or to allow the creation of any noise on property owned, leased, occupied or otherwise controlled by such person, when the foregoing causes the noise level, when measured on any other residential property, either incorporated or unincorporated, to exceed:
(1) 
The noise standard for a cumulative period of more than thirty minutes in any hour; or
(2) 
The noise standard plus five dB(A) for a cumulative period of more than fifteen minutes in any hour; or
(3) 
The noise standard plus ten dB(A) for a cumulative period of more than five minutes in any hour; or
(4) 
The noise standard plus fifteen dB(A) for a cumulative period of more than one minute in any hour; or
(5) 
The noise standard plus twenty dB(A) for any period of time.
(c) 
In the event the ambient noise level exceeds any of the first four noise limit categories set forth in subsection (b) of this section, the cumulative period applicable to said category shall be increased to reflect said ambient noise level. In the event the ambient noise level exceeds the fifth noise limit category, the maximum allowable noise level under said category shall be increased to reflect the maximum ambient noise level.
(Ord. 806 § 2, 1976)
(a) 
The following interior noise standards, unless otherwise specifically indicated, shall apply to all residential property within a designated noise zone:
Interior Noise Standards
Noise Zone
Noise Level
Time Period
1
55 dB(A)
7 a.m. — 10 p.m.
45 dB(A)
10 p.m. — 7 a.m.
In the event the alleged offensive noise consists entirely of impact noise, simple tone noise, speech, music, or any combination thereof, each of the above noise levels shall be reduced by five dB(A).
(b) 
It is unlawful for any person at any location within the city to create any noise, or to allow the creation of any noise on property owned, leased, occupied or otherwise controlled by such person, when the foregoing causes the noise level when measured within any other dwelling unit on any residential property, either incorporated or unincorporated, to exceed:
(1) 
The interior noise standard for a cumulative period of more than five minutes in any hour; or
(2) 
The interior noise standard plus five dB(A) for a cumulative period of more than one minute in any hour; or
(3) 
The interior noise standard plus ten dB(A) for any period of time.
(c) 
In the event the ambient noise level exceeds either of the first two noise limit categories set forth in subsection (b) of this section, the cumulative period applicable to said category shall be increased to reflect said ambient noise level. In the event the ambient noise level exceeds the third noise limit category, the maximum allowable noise level under said category shall be increased to reflect the maximum ambient noise level.
(Ord. 806 § 2, 1976)
The following activities shall be exempted from the provisions of this chapter:
(1) 
Activities conducted on the grounds of any public or private nursery, elementary, intermediate or secondary school or college;
(2) 
Public dances, provided said events are conducted pursuant to a permit issued by the city pursuant to Chapter 5.24 relative to the staging of said events;
(3) 
Activities conducted on any park or playground, provided such park or playground is owned and operated by a public entity;
(4) 
Any mechanical device, apparatus or equipment used, related to or connected with emergency machinery, vehicle or work;
(5) 
Noise sources associated with the construction, repair, remodeling or grading of any real property, provided said activities take place between the hours of seven a.m. and eight p.m. Monday through Friday, nine a.m. through eight p.m. on Saturday and at no time on Sunday or any legal holiday. For purposes of this exception the use of saws, buffers, sanders, drills, and sprayers shall be included, as shall similar activity;
(6) 
All mechanical devices, apparatus or equipment which are utilized for the protection or salvage of agricultural crops during periods of potential or actual frost damage or other adverse weather conditions;
(7) 
Mobile noise sources associated with agricultural operations, provided such operations do not take place between the hours of eight p.m. and seven a.m. on weekdays, including Saturday, or at any time on Sunday or a legal holiday;
(8) 
Mobile noise sources associated with agricultural pest control through pesticide application, provided that the application is made in accordance with the restricted material permits issued by or regulations enforced by the agricultural commissioner;
(9) 
Noise sources associated with the landscape maintenance of real property, provided said activities take place between the hours of seven a.m. and eight p.m. Monday through Friday, nine a.m. through eight p.m. on Saturday, or nine a.m. through six p.m. on Sunday or legal holidays. For purposes of this exception, the phrase "landscape maintenance of real property" shall include, but not be limited to, the use of power mowers, edgers, chain saws, trimmers, hedgecutters, and other devices that are not hand-powered. Leaf blowers shall not be included in said exception and shall be regulated as provided in Chapter 6.10 of this code;
(10) 
Any activity to the extent regulation thereof has been preempted by state or federal law.
(Ord. 806 § 2, 1976; Ord. 1282 § 1, 1998)
It is unlawful for any person to create any noise which causes the noise level at any school, hospital or church while the same is in use to exceed the noise limits as specified in Section 6.28.050 prescribed for the assigned noise zone in which the school, hospital or church is located, or which noise level unreasonably interferes with the use of such institutions or which unreasonably disturbs or annoys patients in the hospital, provided conspicuous signs are displayed in three separate locations within one-tenth of a mile of the institution indicating the presence of a school, church or hospital.
(Ord. 806 § 2, 1976)
The location selected for measuring exterior noise levels shall be at any point on the affected property. Interior noise measurements shall be made within the affected dwelling unit. The measurement shall be made at a point at least four feet from the wall, ceiling, or floor nearest the alleged offensive noise source and may be made with the windows of the affected unit open.
(Ord. 806 § 2, 1976)
The county health officer and his duly authorized representatives are directed to enforce the provisions of this chapter. The county health officer and his duly authorized representatives are authorized, pursuant to Penal Code Section 836.5, to arrest any person without a warrant when they have reasonable cause to believe that such person has committed a misdemeanor in their presence.
No person shall interfere. with, oppose or resist any authorized person charged with enforcement of this chapter while such person is engaged in the performance of his duty.
(Ord. 806 § 2, 1976)
The owner or operator of a noise source which violates any of the provisions of this chapter may file an application with the health officer for a variance from the provisions thereof wherein said owner or operator shall set forth all actions taken to comply with said provisions, the reasons why immediate compliance cannot be achieved, a proposed method of achieving compliance, and a proposed time schedule for its accomplishment. Said application shall be accompanied by a fee in the amount of seventy-five dollars. A separate application shall be filed for each noise source; provided, however, that several mobile sources under common ownership, or several fixed sources on a single property may be combined into one application. Upon receipt of said application and fee, the health officer shall refer it with his recommendation thereon within thirty days to the noise variance board of the county for action thereon in accordance with the provisions of this chapter.
An applicant for a variance shall remain subject to prosecution under the terms of this chapter until a variance is granted.
(Ord. 806 § 2, 1976)
The noise variance board shall evaluate all applications for variance from the requirements of this chapter and may grant said variances with respect to time for compliance, subject to such terms, conditions and requirements as it may deem reasonable to achieve maximum compliance with the provisions of this chapter. Said terms, conditions and requirements may include, but shall not be limited to, limitation on noise levels and operating hours. Each such variance shall set forth in detail the approved method of achieving maximum compliance and a time schedule for its accomplishment. In its determinations said board shall consider the magnitude of nuisance caused by the offensive noise, the uses of property within the area of impingement by the noise, the time factors related to study, design, financing and construction of remedial work, the economic factors related to age and useful life of equipment, and the general public interest and welfare. Any variance granted by said board shall be by resolution and shall be transmitted to the health officer for enforcement. Any violation of the terms of said variance shall be unlawful.
(Ord. 806 § 2, 1976)
(a) 
Within fifteen days following the decision of the variance board on an application the applicant, the health officer, or any member of the city council may appeal the decision to the city council by filing a notice of appeal with the secretary of the variance board. In the case of an appeal by the applicant for a variance, the notice of appeal shall be accompanied by a fee to be computed by the secretary on the basis of the estimated cost of preparing the materials required to be forwarded to the city council as discussed hereafter. If the actual cost of such preparation differs from the estimated cost appropriate payments shall be made either to or by the secretary.
(b) 
Within fifteen days following receipt of a notice of appeal and the appeal fee, the secretary of the variance board shall forward to the city council copies of the application for variance, the recommendation of the health officer, the notice of appeal, all evidence concerning said application received by the variance board and its decision thereon. In addition, any person may file with the city council written arguments supporting or attacking said decision and the city council may in its discretion hear oral arguments thereon. The city clerk shall mail to the applicant a notice of the date set for hearing of the appeal. The notice shall be mailed at least ten days prior to the hearing date.
(c) 
Within sixty days following its receipt of the notice of the appeal, the city council shall either affirm, modify or reverse the decision of the variance board. Such decision shall be based upon the city council's evaluation of the matters submitted to the city council in light of the powers conferred on the variance board and the factors to be considered, both as enumerated in Sections 6.28.120 and 6.28.130.
(d) 
As part of its decision the council may direct the variance board to conduct further proceedings on said application. Failure of the city council to affirm, modify or reverse the decision of the variance board within said sixty-day period shall constitute an affirmation of the decision.
(Ord. 806 § 2, 1976)
Notwithstanding any other provisions of this chapter and in addition thereto, it is unlawful for any person to wilfully make, continue, maintain, permit, or cause to be made, continued, maintained, or permitted, any loud, unnecessary and unusual noise which disturbs the peace or quiet of any residential neighborhood or which causes discomfort or annoyance to any reasonable person of normal sensitivity residing in the area. It shall be a prima facie violation of this section if any radio, receiving set, television, musical instrument or similar device is played, used or permitted to be played or used between the hours of nine p.m. and seven a.m. when audible from a distance of fifty feet from the property line of the noise source or from a distance of one hundred feet from any nonstationary noise source. The determination may be made by a peace officer or may be proven by the testimony of any other person.
(Ord. 1018 § 1, 1985)
No person shall leave standing any motor vehicle, including refrigeration trailers, with engine idling or auxiliary motor running for in excess of ten minutes between the hours of ten p.m. and seven a.m. if the engine or motor noise disturbs the peace or quiet of any residential neighborhood or causes discomfort or annoyance to any reasonable person of normal sensitivity residing in the area. The driver, owner, registered owner and legal owner of the motor vehicle or refrigeration trailer shall each be guilty of the offense described herein.
(Ord. 1156 § 1, 1990)
No person shall make, cause, accept or permit a delivery of goods, merchandise, material, equipment, meat, poultry, fish, groceries, dairy products, foodstuffs, food, or beverage within one hundred feet of a residentially zoned property between the hours of ten p.m. and seven a.m. or at any time on a Sunday or legal holiday so as to disturb the peace and quiet of any reasonable person of normal sensitivity residing in the area. Proof of such a violation may be established by the testimony of a peace officer, code enforcement officer, or any other person. For purposes of this section "delivery" shall not only mean the completed act of a delivery, but all preparatory and related steps taken within the one hundred-foot distance including, but not limited to, driving, stopping, idling or parking a vehicle, the opening or shutting of doors, or the movement of pallets, dolleys, floor jacks, or lifts.
(Ord. 1173 § 1, 1992)
No person shall operate a parking lot sweeper or similar device for cleaning or maintaining commercial property within one hundred feet of a residential area except during the hours of eight a.m. and six p.m., Monday through Friday, between nine a.m. and six p.m. on Saturday, and at no time on Sunday.
(Ord. 1324 § 1, 2002)
Any person violating any of the provisions of this chapter shall be deemed guilty of a misdemeanor. Each day such violation is committed or permitted to continue shall constitute a separate offense and shall be punishable as such. The provisions of this chapter shall not be construed as permitting conduct not prescribed herein and shall not affect the enforceability of any other applicable provisions of law.
(Ord. 806 § 2, 1976)