San Mateo County Municipal Code Ch. 4.88 Noise Control

In order to control unnecessary, excessive and annoying noise in the County of San Mateo, it is hereby declared to be the policy of the County to prohibit such noise generated from or by all sources as specified in this chapter. It shall be the policy of the County to maintain quiet in those areas which exhibit low noise levels and to implement programs aimed at reducing noise in those areas within the County where noise levels are above acceptable values.

It is hereby determined that certain noise levels are detrimental to the public health, welfare and safety, and are contrary to public interest. Therefore, the Board of Supervisors does ordain and declare that creating, causing or maintaining or allowing to be created, caused or maintained, 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.

(Prior code § 4920; Ord. 2803, 10/19/82)

The sound level in decibels as measured with the sound level meter using "A" weighted network. The unit of measurement is referred to herein as dB(A) or dBA.

(Prior code § 4921; Ord. 2803, 10/19/82)

The composite of noise from all sources, near an defined far, excluding the alleged offensive noise. In this context it represents the normal or existing level of environmental noise at a given location for a specified time of the day or night.

(Prior code § 4922; Ord. 2803, 10/19/82)

Any building, structure, premise or portion thereof used for wholesale or retail commercial purposes.

(Prior code § 4923; Ord. 2803, 10/19/82)

Any site preparation, assembly, erection, substantial repair, or alteration of any building, structures, or land, public or private, together with any associated scientific or engineering surveys.

(Prior code § 4924; Ord. 2803, 10/19/82)

An additive period of time composed of individual time segments which may be continuous or interrupted.

(Prior code § 4925; Ord. 2803, 10/19/82)

A unit for measuring the amplitude of a sound, equal to twenty times the logarithm to the base ten of the ratio of the pressure of the sound measured to the reference pressure, which is twenty micropascals.

(Prior code § 4926; Ord. 2803, 10/19/82)

Any dismantling, intentional destruction, or removal of structures, surfaces, or similar property, public or private.

(Prior code § 4927; Ord. 2803, 10/19/82)

Any building or separate portion thereof used for residential purposes. The term shall include, but not be limited to, single family dwellings, apartments, condominiums, and other distinct residential units.

(Prior code § 4928; Ord. 2803, 10/19/82)

Any work performed to protect, maintain, or restore safe and/or healthy conditions in the community, along with work performed by private or public utilities when restoring utility service.

(Prior code § 4929; Ord. 2803, 10/19/82)

Noise which impacts the area outside the outermost walls of any dwelling unit.

(Prior code § 4930; Ord. 2803, 10/19/82)

A device or machine which creates sounds while fixed or stationary, including, but not limited to, residential, agricultural, industrial and commercial machinery and equipment, pumps, fans, compressors, air conditioners, refrigeration equipment, and construction equipment moving within the fixed boundaries of a construction site.

(Prior code § 4931; Ord. 2803, 10/19/82)

The Health Officer of the County or his duly authorized deputy.

(Prior code § 4932; Ord. 2803, 10/19/82)

Any building or portion thereof used for the accommodation and medical care of sick, injured, or infirm Persons and includes rest homes, nursing homes and convalescent hospitals.

(Prior code § 4933; Ord. 2803, 10/19/82)

A noise of short duration, usually less than one second, with an abrupt onset and rapid decay.

(Prior code § 4934; Ord. 2803, 10/19/82)

Noise which impacts the area within the outermost walls of any dwelling unit.

(Prior code § 4935; Ord. 2803, 10/19/82)

A noise that is repeated at non-uniform time intervals.

(Prior code § 4936; Ord. 2803, 10/19/82)

Any building, structure, factory, plant, premise or portion thereof used for manufacturing or industrial purposes.

(Prior code § 4937; Ord. 2803, 10/19/82)

That noise which intrudes over and above the existing background noise at a given location. The relative intrusiveness of a sound depends upon its level, duration, frequency, time of occurrence, and tonal or informational content as well as the prevailing background noise level.

(Prior code § 4938; Ord. 2803, 10/19/82)

The sound level created, caused, maintained, or originating from an alleged offensive intrusive noise source, measured in decibels, at a specified location while the alleged offensive intrusive noise source is in operation.

(Prior code § 4939; Ord. 2803, 10/19/82)

Any noise source other than a fixed noise source.

(Prior code § 4940; Ord. 2803, 10/19/82)

Any sound which (1) endangers or injures the safety or health of human beings or (2) annoys or disturbs Persons of normal sensitivities, or (3) endangers or injures personal or real property, or (4) violates the factors set forth in section 4.88.380 of this chapter, or (5) violates the quantitative standards set forth in section 4.88.360 and section 4.88.370.

(Prior code § 4941; Ord. 2803, 10/19/82)

Any individual, association, partnership, or corporation, and includes any officer, employee, department, agency or instrumentality of a State or any political subdivision of a State, or any other entity, public or private in nature.

(Prior code § 4942; Ord. 2803, 10/19/82)

The imaginary lines along the ground surface, and their vertical extension, which separate the real property owned by one Person from that owned by another Person, but not including intra-building real property divisions.

(Prior code § 4943; Ord. 2803, 10/19/82)

A noise that is repeated at relatively uniform time intervals.

(Prior code § 4944; Ord. 2803, 10/19/82)

A parcel of real property which is developed and used either in whole or in part for residential purposes, other than transient use such as hotels or motels.

(Prior code § 4945; Ord. 2803, 10/19/82)

Any public or private institution conducting regular academic instruction or planned activity at the preschool, elementary, secondary or collegiate levels, or which provides adult or continuing education.

(Prior code § 4946; Ord. 2803, 10/19/82)

Any noise which is distinctly audible as a single pitch (frequency) or set of pitches as determined by the Health Officer.

(Prior code § 4947; Ord. 2803, 10/19/82)

An instrument, including a microphone, an amplifier, an output meter, and frequency weighting networks, for the measurement of sound levels which meets the American National Standards 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.

(Prior code § 4948; Ord. 2803, 10/19/82)

The noise control program established by this Ordinance shall be administered by the Health Officer.

(Prior code § 4950; Ord. 2803, 10/19/82)

In order to implement and enforce this Ordinance the Health Officer shall have the power to:

a) Coordinate the noise control program established by this Ordinance with all other governmental agencies.

b) Conduct public education in all aspects of noise control.

c) Conduct all necessary inspections, monitoring, and surveys necessary for the enforcement of this Ordinance.

d) Establish an interdepartmental noise enforcement responsibility and procedures document relative to the investigation of noise complaints. This procedure shall define jurisdictional responsibilities of the Environmental Health section, Sheriffs Department, Planning Department and Department of Animal Control.

e) Enter into contracts, with the approval of the Board of Supervisors, for the provision of technical and enforcement services to the Cities of the County.

(Prior code § 4951; Ord. 2803, 10/19/82)

All noise measurements taken for the enforcement of this chapter shall be in accordance with the following criteria:

a) Any noise measurement made pursuant to the provisions of this Ordinance shall be made with a sound level meter as defined in section 4.88.290. The "A" weighted network (scale) at "slow" response shall be used to measure the sound level. The "fast" or "impulsive" response shall be used to measure impulsive type sound levels; the response used shall be stated. The time durations for each of the sound levels occurring shall be measured, together with the duration of the measurements.

b) Calibration of the measurement equipment utilizing an acoustic calibrator shall be performed immediately prior to recording any noise data.

c) A windscreen shall be used on the sound level meter for all sound measurements. No external measurements shall be made during precipitation, or if wind speed exceeds 12 miles per hour.

d) Exterior noise levels shall be measured within 50 feet of the affected residence, school, hospital, church, public library but in no case beyond the property line. Where practical, the microphone shall be positioned four to five feet above the ground and ten feet or more away from any reflective surface. The location of microphone and adjacent surfaces shall be described. The microphone orientation shall be as recommended by the sound meter manufacturer.

e) Interior noise levels shall be measured within the affected dwelling unit at a point at least four feet from the wall, ceiling, or floor nearest the noise source, with windows in the normal seasonal configuration. The microphone location and room configuration shall be described.

(Prior code § 4952; Ord. 2803, 10/19/82)

It is unlawful for any Person at any location within the unincorporated area of the County to create any noise, or to allow the creation of any noise on property owned, leased, occupied or otherwise controlled by such Person which causes the exterior noise level when measured at any single or multiple family residence, school, hospital, church, public library situated in either the incorporated or unincorporated area to exceed the noise level standards as set forth in Table I following:

Table I - Receiving Land use: Single or Multiple Family Residence, School, Hospital, Church, or Public Library Properties.

NOISE LEVEL STANDARDS, dBA

a) In the event the measured background noise level exceeds the applicable noise level standard in any category above, the applicable standard shall be adjusted in five (5) dBA increments so as to encompass the background noise level.

b) Each of the noise level standards specified above shall be reduced by 5 dBA for simple tone noises, consisting primarily of speech or music, or for recurring or intermittent impulsive noises.

c) If the intruding noise source is continuous and cannot reasonably be stopped for a period of time whereby the background noise level can be measured, the noise level measured while the source is in operation shall be compared directly to the noise level standards in Table I.

(Prior code § 4953; Ord. 2803, 10/19/82)

No Person shall, at any location within the unincorporated area of the County operate, or cause to be operated within a dwelling unit, any source of sound, or create, or allow the creation of, any noise which causes the noise level when measured inside a receiving dwelling unit with windows in their normal seasonal configuration to exceed the following noise level standards as set forth in Table II following:

Table II - Interior Noise Level Standards - Dwelling Unit

NOISE LEVEL STANDARDS, dBA

a) In the event the measured background noise level exceeds the applicable noise level standard in any category above, the applicable standard shall be adjusted in five (5) dBA increments so to encompass the background noise level.

b) Each of the noise level standards specified above shall be reduced by 5 dBA for simple tone noises, noises consisting primarily of speech or music, or for recurring or intermittent impulsive noises.

c) If the intruding noise source is continuous and cannot reasonably be stopped for a period of time whereby the background noise level can be measured, the noise level measured while the source is in operation shall be compared directly to the noise level standards in Table II.

(Prior code § 4954; Ord. 2803, 10/19/82)

Notwithstanding any other provision of this Ordinance, it shall be unlawful for any Person to willfully or negligently make or continue, or cause to be made or continued any unreasonably loud, unnecessary, or unusual noise which disturbs the peace and quiet of any neighborhood or which causes any discomfort or annoyance to any Person of normal sensitivity residing in the area. The factors which shall be considered in determining whether a violation of the provisions of this section exist include the following:

a) The sound level of the objectionable noise.

b) The sound level of the background noise.

c) The proximity of the noise to residential sleeping or hospital facilities.

d) The nature and zoning of the area from which the noise emanates and upon which the noise impacts.

e) The number of Persons affected by the noise sources.

f) The time of day or night the noise occurs.

g) The duration of the noise and its tonal, informational, or musical content.

h) Whether the noise is continuous, recurrent, or intermittent.

i) Whether the noise is produced by a commercial or non-commercial activity.

(Prior code § 4955; Ord. 2803, 10/19/82)

The following activities shall be exempted from the provisions of this chapter:

a) School bands, school athletic and school entertainment events.

b) Outdoor gatherings, public dances, shows and sporting and entertainment events providing said events are conducted pursuant to all County regulations.

c) Activities conducted on parks, public playgrounds and school grounds provided such parks, playgrounds and school grounds are owned and operated by a public entity.

d) Any mechanical device, apparatus or equipment used, related to or connected with emergency machinery, vehicle or work.

e) Noise sources associated with demolition, construction, repair, remodeling, or grading of any real property, provided said activities do not take place between the hours of 6:00 P.M. and 7:00 A.M. weekdays, 5:00 P.M. and 9:00 A.M. on Saturdays or at any time on Sundays, Thanksgiving and Christmas.

f) 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.

g) Mobile noise sources associated with agricultural operations provided such operations do not take place between the hours of 8:00 P.M. and 7:00 A.M.

h) Mobile noise sources associated with agricultural pest control through pesticide application provided that the application is made in accordance with restricted material permits issued by or regulations enforced by the Agricultural Commissioner.

i) Noise sources associated with the maintenance of real property used for residential purposes provided said activities take place between the hours of 7:00 A.M. and 8:00 P.M.

j) Any activity to the extent regulation thereof has been preempted by State or Federal law.

(Prior code § 4956; Ord. 2803, 10/19/82; Ord. 3208, 03/06/90)

During the three year period following the effective date of this chapter, the noise standards enumerated in section 4.88.330 and section 4.88.340 shall be increased by eight (8) dBA where the alleged offensive noise source is an air conditioning or refrigeration system or associated equipment which was installed prior to the effective date of this chapter.

(Prior code § 4958; Ord. 2803, 10/19/82)

Whenever, for the good of the public, a government agency, public utility, or private utility determines a project must be done before 7:00 A.M., or after 6:00 P.M., or weekends, and so states in its contract, change order(s), or bid documents, said work shall be exempted from this chapter.

(Prior code § 4959; Ord. 3208, 03/06/90; catchline editorially created, 6/94)

The Planning Commission of the County of San Mateo shall serve as the Noise Board of Review.

(Prior code § 4960; Ord. 2803, 10/19/82)

This Noise Board of Review is authorized to grant variances for exception from any provision of this Ordinance, subject to imposed limitations as to area, noise levels, time limits, and any other terms and conditions the Noise Board of Review determines are appropriate to protect the public health, safety and welfare. Three (3) members shall constitute a quorum and at least three (3) affirmative votes shall be required in support of any action. This section shall in no way be construed as granting authority to operate or conduct any activity which is otherwise regulated by law.

(Prior code § 4961; Ord. 2803, 10/19/82)

Any Person seeking a variance for a noise source which the Health Officer has determined violates any provision of this Ordinance may file an application with the Noise Board of Review Secretary. Said application shall be accompanied by a fee in the amount of Fifty Dollars ($50.00). The application shall contain information that demonstrates that bringing the noise source into compliance with this Ordinance would constitute an unreasonable hardship on the applicant, the community, or on other Persons. The applicant shall also set forth any actions already taken to comply with the provisions of this Ordinance. A separate application shall be filed for each noise source; provided, however, that several mobile sources operating within the boundaries of a single property may be combined into one application. Notice of an application for a variance shall be published (according to established jurisdictional procedure). Any individual who claims to be adversely affected by the allowance of the variance may file a statement with the Noise Board of Review containing any information to support his/her claim.

Upon receipt of the application and all supporting evidence deemed necessary by the Noise Board of Review, the Board shall within (30) days, (1) approve the application in whole or in part, or (2) deny the application.

Applicants for variances and Persons contesting variances may be required to submit such information as the Board may reasonably require. In granting or denying an application, the Board Secretary shall keep on public file a copy of the decision and the reason for granting or denying the variance.

(Prior code § 4962; Ord. 2803, 10/19/82)

In determining whether to grant or deny an application for variance the following criteria shall be considered:

a) The magnitude of nuisance caused by the offensive noise,

b) The uses of property within the area of impingement by the noise,

c) The time factors related to study, design, financing and construction of remedial work,

d) The economic factors related to age and useful life of equipment,

e) The general public interest and welfare.

f) Whether strict compliance with the requirement of this chapter will cause practical difficulties, unnecessary hardship or unreasonable expense and any other relevant considerations, including but not limited to, the fact that a commercial or industrial facility as defined in section 4.88.040 and section 4.88.180 commenced development prior to the existence of a resident affected by noise from such facility.

g) The extent to which a commercial or industrial applicant has endeavored to reduce noise.

(Prior code § 4963; Ord. 2803, 10/19/82; Ord. 2870, 1/3/84)

In the event the variance is granted, the applicant shall be notified of all conditions, which may include restrictions on noise level, noise duration and operating hours, an approved method of achieving compliance, and a time schedule for its implementation. The variance shall not become effective until all conditions are agreed to by the applicant. Noncompliance with any condition of the variance shall terminate the variance and subject the Person holding it to those provisions of this Ordinance for which the variance was granted.

(Prior code § 4964; Ord. 2803, 10/19/82)

A variance will not exceed one (1) year from the date on which it was granted. Application for extension of the time limits specified in variances or for modification of other substantial conditions shall be treated like applications for initial variances under this chapter.

(Prior code § 4965; Ord. 2803, 10/19/82)

Within fifteen (15) days following the decision of the Noise Board of Review, the applicant may appeal the decision to the Board of Supervisors by filing a notice of appeal with the Clerk of the Board of Supervisors. The Board of Supervisors shall either affirm, modify, or reverse the decision of the Noise Board of Review. Such decision shall be final and shall be based upon such considerations as are set forth in this chapter.

(Prior code § 4967; Ord. 2803, 10/19/82)

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 proscribed herein and shall not affect the enforceability of any other applicable provisions of law.

(Prior code § 4968; Ord. 2803, 10/19/82)

The primary responsibility for the enforcement of the provisions of this chapter shall be with the Health Officer. The Sheriff may also enforce the provisions of this chapter in his area of responsibility as described in the interdepartmental noise enforcement responsibility and procedure document established under section 4.88.310 of this chapter.

(Prior code § 4969; Ord. 2803, 10/19/82)