In order to control unnecessary, excessive, and annoying noise in the City of Mill Valley, it is declared to be the policy of the City to prohibit such noise generated from or by all sources as specified in this chapter. It shall be the policy of the City to maintain quiet in those areas which have low noise levels and to implement programs aimed at reducing noise in those areas within the City where noise levels are above acceptable values.
It is determined that certain noise levels are detrimental to the public health, welfare and safety, and are contrary to the public interest. Therefore, the City Council does ordain and declare that creating, maintaining, or causing directly or indirectly any noise in a manner prohibited by or not complying with the provisions of this chapter is a public nuisance and shall be punishable as such.
(Ord. 899 § 1, September 19, 1977; Ord. 1174 § 1, February 5, 2001)
As used in this chapter, unless the context otherwise clearly indicates, the words, phrases, and terms used in this chapter are defined as follows:
"'A' weighted network"
means an electrical network utilized in a sound level meter to provide a prescribed frequency response. The frequency response characteristics are those specified in American National Standards Institute publication SI 4-1971, or the most recent revision thereof.
"'A' weighted sound level"
means total sound level in decibels of all sound as measured with a sound level meter using the slow meter response and the "A" weighted network. The reference pressure shall be 20 microPascals.
"Agricultural property"
means a parcel of property which is undeveloped for any use other than agricultural purposes.
"Ambient noise"
means the all-encompassing noise associated with a given environment, being usually a composite of sounds from many sources near and far. For the purpose of this chapter, "ambient noise level" is the lowest tendency of the sound level meter needle which is repeated during a 10-minute period of observation. The ambient level is approximately equal to L90, which is the level exceeded 90% of the time.
"'C' weighted network"
means an electrical network utilized in a sound level meter to provide a prescribed frequency response. The frequency response characteristics are those specified in American National Standards Institute publication SI 4-1971, or the most recent revision thereof.
"Commercial purpose,"
in relation to sound amplifying equipment, means the use, operation, or maintenance of any sound amplifying equipment for the purpose of advertising any business, or any goods, or any services, or for the purpose of attracting the attention of the public to, or advertising for, or soliciting patronage of customers to or for any performance, show, entertainment, exhibition, or event, or for the purpose of demonstrating such sound equipment.
"Construction"
means any site preparation, assembly, installation, development, substantial repair, alteration, demolition or similar activity, public or private rights-of-way, structures, improvements, utilities, or other property.
"Decibel"
means one-tenth of a bel. Thus, a decibel is 10 times the logarithm to the base 10 of a ratio of two quantities which are proportional to power.
"Emergency work"
means any work necessary to restore property to a safe condition following a public calamity or work required to protect persons or property from an imminent exposure to danger 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, residential, agricultural, and commercial machinery and equipment, pumps, fans, compressors, air conditioners, and refrigeration equipment.
"Impulsive noise"
means a noise characterized by brief excursions of sound pressures whose peak levels are very much greater than the ambient noise level (such as might be produced by the impact of a pile driver) typically with one second or less duration.
"Intruding noise level"
means the total sound level created, caused, maintained, or originating from an alleged offensive source in decibels at a specified location while the alleged offensive source is in operation.
"Legal holiday"
means the following days: the first day of January, the third Monday in January, the 12th day in February, the third Monday in February, the last Monday in May, the fourth day of July, the first Monday in September, the 11th day in November, Thanksgiving Day, the 25th day of December, or any other holiday designated by the State of California.
"Licensed"
means the issuance of a formal license or a permit by the appropriate jurisdictional authority; or, where no permits or licenses are issued, the sanctioning of the activity by the jurisdiction as noted in public record.
"Mobile noise source"
means any noise source other than a fixed noise source.
"Motor vehicle"
means, but is not limited to, automobiles, trucks, motorcycles, minibikes, and go-carts.
"Noncommercial purpose"
in relation to sound amplifying equipment means the use, operation, or maintenance of any sound equipment for other than a commercial purpose including, but not limited to, philanthropic, political, patriotic, and charitable purposes.
"Owner/occupant builder"
means the person residing at the property upon which improvements are being made, or his/her immediate family.
"Person"
means any individual, firm, association, co-partnership, joint venture, corporation, or any entity, public or private in nature.
"Property plane"
means a vertical plane including the property line which determines the property boundaries in space.
"Recreation area"
means a public park or other public land maintained for active recreation or any private land legally maintained for active recreation.
"Sound amplifying equipment"
means any machine or device for the amplification of the human voice, music, or any other sound, excluding standard automobile radios when used and heard only by the occupants of the vehicle in which the radio is installed.
"Sound level meter"
means an instrument, including a microphone with wind screen, an amplifier, an output meter, and frequency weighting networks for the measurement of sound levels, which satisfy the requirements pertinent for type S2A meters in American Standard Specifications for sound level meters, SI 4-1971, or the most recent revision thereof. The sound level meter and calibrator shall be certified annually by an independent authorized service agency to insure instruments meet the specifications.
"Sound pressure level."
The "sound pressure level" in decibels of a sound is 20 times the logarithm to the base 10 of the ratio of the pressure of this sound to the reference pressure. The reference pressure shall be 20 microPascals.
"Sound truck"
means any motor vehicle, or any other vehicle regardless of motive power, whether in motion or stationary, having any sound amplifying equipment mounted on or attached to it.
"Tone."
A noise possesses "tones" or "tonal content" when the auditory sensation of pitch is distinguishable in the noise.
(Ord. 899 § 1, September 19, 1977; Ord. 1174 § 1, February 5, 2001)
A. 
Departmental Actions. All departments shall, to the fullest extent consistent with their authorities under other laws administered by them, carry out their programs in such a manner as to further the policies stated in Section 7.16.010.
B. 
Project Approval. Each department whose duty it is to review and approve new projects or changes to existing projects that result or may result in the emission of noise shall require compliance with this chapter.
C. 
Low Noise Emission Products. The City is encouraged to use low noise emission products. Products which have been certified by the Administrator of the U.S. Environmental Protection Agency pursuant to Section 15 of the Noise Control Act of 1972, as low noise emission products should be used in preference to any other products when practicable.
(Ord. 899 § 1, September 19, 1977; Ord. 1174 § 1, February 5, 2001)
A. 
Investigation. Upon receipt of a complaint from a citizen, the enforcing officer or his/her designee, equipped with a sound level meter satisfying the requirements specified in Section 7.16.020, shall investigate the complaint. The investigation shall consist of a measurement and the gathering of data to adequately define the noise problem, including the following:
1. 
Nonacoustic data;
2. 
Type of noise source;
3. 
Location of noise source relative to complainant's property;
4. 
Time period during which noise source is considered by complainant to be intrusive;
5. 
Total duration of noise produced by noise source;
6. 
Date and time of noise measurement survey.
B. 
Noise Measurement Procedure. Utilizing the "A" or "C" weighting scale of the sound level meter and the "slow" meter response, the noise level shall be measured at a position or positions along the complainant's property line closest to the noise source or at the location along the boundary line or on the complainant's property where the noise level is at the maximum level. Generally, the microphone shall be located five feet above the ground unless another elevation is deemed appropriate. If the noise complaint is related to interior noise levels, interior noise measurements shall be made within the affected residential unit. The measurements shall be made at a point at least four feet from the wall, ceiling, or floor nearest the noise source. Calibration of the instrument being used shall be performed immediately prior to and immediately after recording any noise data utilizing an acoustic calibrator. The noise levels at the property line, with the alleged noise source in operation, shall be recorded on a data sheet, along with other pertinent data.
If possible, the ambient noise shall be measured at the same locations along the property line utilized in the preceding paragraph, with the alleged offending noise source inoperative. The noise levels measured for this condition shall also be recorded on the survey data sheet. If for any reason the alleged offending noise source cannot be shut down, then the ambient noise must be estimated by performing a measurement in the same general area of the source but at a sufficient distance such that the noise from the source is inaudible. If the difference between the noise levels with noise source operating and not operating is six decibels or greater, then the noise measurement of the alleged source can be considered valid with a small correction applied to account for the contribution of the ambient noise. The correction is to be applied in accordance with data shown in Table A-1.
TABLE A-1
BACKGROUND NOISE CORRECTION FOR SOUND LEVEL MEASUREMENTS
Difference between total noise and background noise alone
(Decibels)
Amount to be subtracted from total noise measurement
(Decibels)
6 - 8
1
8 - 10
0.5
10
0
(Ord. 899 § 1, September 19, 1977; Ord. 1174 § 1, February 5, 2001)
A. 
Notwithstanding any other provision of this chapter, it is unlawful for any person to willfully make or cause to be made any loud, unnecessary, or unusual noise which disturbs the peace and quiet of any neighborhood or which causes discomfort or annoyance to any reasonable person of normal sensitiveness residing in the area.
B. 
The standards which shall be considered in determining whether a violation of the provisions of this section exists shall include, but not be limited to, the following:
1. 
The sound level of the objectionable noise;
2. 
The sound level of the ambient noise;
3. 
The proximity of the noise to residential sleeping facilities;
4. 
The nature and zoning of the area within which the noise emanates;
5. 
The density of the inhabitation of the area within which the noise emanates;
6. 
The time of day or night the noise occurs;
7. 
The duration of the noise and its tonal content;
8. 
Whether the noise is continuous, recurrent, or intermittent;
9. 
Whether the noise is produced by a commercial or noncommercial activity;
10. 
The intensity of the noise;
11. 
Whether the noise is natural or unnatural;
12. 
Whether the noise is usual or unusual;
13. 
Compliance with any project conditions of approval.
(Ord. 899 § 1, September 19, 1977; Ord. 1174 § 1, February 5, 2001)
A. 
The noise limits specified in Table A-2 as adjusted by Table A-4 shall, unless otherwise specifically indicated, apply to all property within a designated zone. It is unlawful for any person to create, maintain, or cause any noise which exceeds such limits when measured in the manner and at the locations set forth in Section 7.16.040.
B. 
The numerical limits given in Table A-2 and in Table A-3 shall be adjusted by the addition of the following adjustments where appropriate:
Noise Condition
Adjustment to Limits
(in Decibels)
1. Noise contains a steady, audible tone, such as a whine, screen or hum
-5
2. Noise is repetitive, impulsive noise, such as hammering, riveting or barking
-5
3. Noise occurs more than five but less than 15 minutes per hour
+5
4. Noise occurs more than one but less than five minutes per hour
+10
5. Noise occurs less than one minute per hour
+20
C. 
If the measurement location is on a boundary between two different zones, the noise level limit applicable to the lower noise zone shall apply.
TABLE A-2
Zone
Time
Noise level (dBA)* **
Single family Residential and Open Areas (RS, RP, OA)
9:00 p.m.—7:00 a.m.
45
 
7:00 a.m.—9:00 p.m.
50
Multi-family Residential (all RM)
9:00 p.m.—7:00 a.m.
50
 
7:00 a.m.—9:00 p.m.
55
Professional-Administrative (PA)
9:00 p.m.—7:00 a.m.
55
 
7:00 a.m.—9:00 p.m.
60
Commercial (CG and CR)
9:00 p.m.—7:00 a.m.
55
 
7:00 a.m.—9:00 p.m.
65
*
Refer to Section 6.04.179 of this Code relating to animal nuisances.
**
In the case of an elevated or directional sound source, compliance with the noise limits is to be maintained at any location or elevation along and beyond the property line.
(Ord. 899 § 1, September 19, 1977; Ord. 1174 § 1, February 5, 2001)
A. 
No person shall create or maintain or cause to be created or maintained within the interior of a multi-family dwelling four feet from any wall, floor, or ceiling any noise which exceeds the limits of Table A-3 below, as adjusted by correction factors under subsection B of Section 7.16.060, and as adjusted by Table A-4 except within the apartment where the noise source or sources may be located.
B. 
All school, hospital, and residential uses and construction commenced after October 19, 1977, shall employ construction methods and materials which the Building Inspector and/or City Engineer determine will ensure compliance with the limits specified in Table A-3.
TABLE A-3
Type of Land Use
Time Interval
Allowable Interior Noise Level (dBA)
Residential
9:00 p.m.—7:00 a.m.
35
 
7:00 a.m.—9:00 p.m.
45
School
7:00 a.m.—9:00 p.m.
45
Hospital
Any Time
35
(Ord. 899 § 1, September 19, 1977; Ord. 1174 § 1, February 5, 2001)
The following activities shall be exempted from the provisions of this chapter:
A. 
Occasional outdoor gatherings, public dances, shows, and sporting and entertainment events, provided such events are conducted pursuant to a permit or license issued by the City relative to the staging of such events;
B. 
Any mechanical device, apparatus or equipment used, related to, or connected with any emergency machinery, vehicle, work or warning alarm or bell, provided the sounding of any bell or alarm on any building or motor vehicle shall terminate its operation within 15 minutes of its being activated;
C. 
Noise sources associated with or vibration created by construction, repair, remodeling, or grading of any real property or during authorized seismic surveys, provided such activities do not take place between the hours of 6:00 p.m. and 7:00 a.m. on weekdays, or at any time on Saturday, Sunday or a legal holiday and provided any vibration created does not endanger the public health, welfare and safety. Heavy equipment and power tools are restricted to weekdays between the hours of 8:00 a.m. and 5:00 p.m. Owner/occupant builders are exempt from the time and heavy equipment and power tools restrictions on Saturdays between the hours of 9:00 a.m. and 5:00 p.m.
D. 
The use of backup, emergency generators during a prolonged power outage or emergency, as declared by the City of Mill Valley, state or local government agency, provided that the generator's owner has a building permit and the generator complies with current fire and building codes. During a prolonged power outage period, generators for commercial uses may be operational 24 hours per day but should be shut off when not critically needed to minimize the disturbance of neighbors. Generators for residential uses shall comply with setback standards of the underlying zoning district, be placed in an area that is reasonably practical for the homeowner that is least disruptive to neighbors. Generators supporting residential uses shall not be operated during the hours of 9:00 p.m. to 7:00 a.m., except as required for a bonafide health or medical need. Testing of emergency generators shall be limited to the hours between 9:00 a.m. and 8:00 p.m. on any day and shall be limited in duration to that specified by manufacturer's specifications. Generator installations require a building permit from the City's Building Division. For the purpose of this section a "prolonged power outage" means a power outage that is no less than four hours in duration.
(Ord. 899 § 1, September 19, 1977; Ord. 1174 § 1, February 5, 2001; Ord. 1310 § 1, September 16, 2019; Ord. 1332 § 2, December 6, 2021)
A. 
Motor Vehicles. It is unlawful for any person to operate any motor vehicle which is not subject to registration under the Vehicle Code in such a manner that the noise limits described in Section 23130 of the Vehicle Code are exceeded. Any measured noise level exceeding these limits shall be deemed to be prima facie evidence of a violation of the provisions of this section.
B. 
Hawkers and Peddlers. It is unlawful for any person to sell anything by outcry within any area of the City zoned for residential uses. The provisions of this section shall not be construed to prohibit the selling by outcry of merchandise, food, and beverages at licensed sporting events, parades, fairs, circuses, or other similar licensed public entertainment events.
C. 
Attracting Attention Using Noise. It is unlawful for any person to use any drum or other instrument or device of any kind for the purpose of attracting attention by the creation of noise. This section shall not apply to any person who is a participant in a school band or duly licensed parade, or who has been otherwise duly licensed to engage in such conduct.
D. 
Construction Projects. Construction projects shall not take place between the hours of 6:00 p.m. and 7:00 a.m. on weekdays, or at any time on Saturday, Sunday, or a legal holiday without issuance of a special permit. Exception: No permit is required to perform emergency work. Contractors shall be required to prominently display a notice of the date of commencement of construction noise at least three days prior to actual commencement. Such notice shall be located on the construction site and shall be readable from the closest adjacent street.
E. 
Amplified Sound. While recognizing that the use of sound amplifying equipment is protected by the constitutional rights of freedom of speech and assembly, the City nevertheless feels obligated to reasonably regulate the use of sound amplifying equipment in order to protect the correlative constitutional rights of the citizens of this community to privacy and freedom from public nuisance of loud and unnecessary noise.
1. 
Amplified Sound Out-of-Doors—Permit Required. Persons intending to install, use or operate within the City a loudspeaker or sound amplifying equipment in a fixed or moveable position or mounted upon any sound truck for the purpose of giving instructions, directions, talks, addresses, lectures, or transmitting music to any persons or assemblages of persons in or upon any private property out-of-doors or upon any street, alley, sidewalk, park, or public property out-of-doors shall obtain a permit from the City. Such permit shall be issued for one day at a time and shall allow the operation of the amplifying equipment between the hours of 9:00 a.m. and 6:00 p.m. on weekdays and Saturday and between 12:00 noon and 6:00 p.m. on Sundays and legal holidays. The equipment shall be controlled by the permit holders so as not to disturb or be a nuisance to a person of normal sensitiveness. The only sounds allowed shall be of music or of human speech.
2. 
Amplified Sound Emanating From Within a Building. Amplified sound emanating from within a building shall not exceed limits in Table A-2 at and beyond the property line.
F. 
Noise Arising from Residential Activities. Certain types of activities and noise sources associated with residential living, although not considered acceptable by most residential inhabitants, are, nevertheless, tolerated. It is the purpose of this section to allow these noise sources to persist, however, at controlled noise levels and at specified times. The general noise limits of Table A-2 and the specified adjustments of subsection B of Section 7.16.060 apply to the noise sources listed in Table A-4 below, except during the time periods specified. The higher noise limits listed in Table A-4 are allowed only between the hours of 7:00 a.m. and 9:00 p.m. on weekdays and between the hours of 9:00 a.m. and 9:00 p.m. on Saturdays, and on Sundays and legal holidays as designated in Table A-4.
TABLE A-4
Noise Source Type
Noise Levels (dBA)
Sundays and Legal Holidays
Power garden equipment
80
Limits set in Table A-2
People during outdoor activities
70
12:00 noon to 9:00 p.m.
Musical activity indoors
Adjustments to +10 to limits in Table A-2
12:00 noon to 9:00 p.m.
G. 
Noise Arising From Activities in Recreation Areas. Activity noise levels in any recreation area shall not exceed 70 dBA between 7:00 a.m. and 9:00 p.m. on any day. The limits of Table A-2 shall apply between 9:00 p.m. and 7:00 a.m.
H. 
Noise Arising From Activities at Tennis Courts. Activity noise levels at municipal tennis courts and at private tennis clubs shall not exceed 70 dBA between 7:00 a.m. and 10:00 p.m. on any day. The limits of Table A-2 shall apply between 10:00 p.m. and 7:00 a.m.
I. 
Gasoline Powered Blowers. It shall be unlawful for any person to operate a gas-powered device to blow leaves, dirt or other debris off sidewalks, driveways, lawns or other surfaces within any area of the City.
(Ord. 1119, January 4, 1993; Ord. 1332 § 2, December 6, 2021)
A. 
The owner or operator of a noise source which violates any of the provisions of this chapter may apply for a variance from the regulations designated in this chapter, on the basis of undue hardship, to the Planning Commission. Any variance granted by the Planning Commission shall contain all conditions upon which said variance has been granted and shall specify a reasonable time period that the variance shall be effective. The Planning Commission may grant the variance as applied for only if it is found that:
1. 
Additional time is reasonably necessary for the applicant to alter or modify his or her activity or operation to comply with this chapter; or
2. 
The activity, operation or noise source will be of temporary duration, and cannot be done in a manner that would comply with this chapter; or
3. 
No other reasonable alternative is available to the applicant.
B. 
The Planning Commission may prescribe any reasonable conditions or requirements it deems necessary to minimize adverse effects upon the community or the surrounding neighborhood.
C. 
The application shall be accompanied by a fee as established by the City Council.
D. 
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.
E. 
An applicant for a variance shall remain subject to prosecution under the terms of this chapter until a variance is granted.
(Ord. 899 § 1, September 19, 1977; Ord. 1174 § 1, February 5, 2001)
Any noise exceeding the noise level limits specified in Sections 7.16.060 and 7.16.070 and as adjusted by Table A-4 shall be deemed to be prima facie evidence of a violation of the provisions of this chapter.
(Ord. 899 § 1, September 19, 1977; Ord. 1174 § 1, February 5, 2001)
A. 
City Engineer—Police Department—Building Official. Responsibility for enforcement of this chapter shall be delegated to the offices of the City Engineer, the Building Official or the Police Department. Requests for special permits for construction projects shall be directed to the office of the City Engineer. Such permits may be issued in accordance with subsection D of Section 7.16.090. The City Engineer and/or the Building/Zoning Code Inspector, acting as his or her designee, shall be satisfied that appropriate methods are employed in new construction and new uses in order to meet the interior noise standards specified in Table A-4.
Complaints about construction noise which are made during the working day (9:00 a.m. to 5:00 p.m., Monday through Friday) shall be investigated by the City Engineer, Building Official or his or her designee. Complaints about all other noises shall be investigated by an officer of the Police Department. When the office of the City Engineer or Building Official is closed, complaints about construction noises shall also be investigated by a police officer.
B. 
Enforcement Procedure. Whenever the enforcing officer has reason to believe that the noise level limits of this chapter have been violated, he or she shall see that noise measurements in accordance with the procedures specified in Section 7.16.040 are performed.
C. 
Interference With Enforcement Procedures. No person shall interfere with, oppose, or resist any authorized person charged with the enforcement of this chapter while such person is engaged in the performance of his or her duty.
D. 
Immediate Threat to Health and Welfare. The enforcing officer shall order an immediate halt to any sound in excess of limits established by this chapter which exposes any person to an immediate threat to health and welfare.
E. 
Report and Evaluation. The City Engineer, Building Official and the police officers involved in this program shall keep records of their activities in enforcing the noise regulations and shall submit a report and evaluation together with recommendations to the City Manager annually.
(Ord. 899 § 1, September 19, 1977; Ord. 1174 § 1, February 5, 2001)
If any provision, clause, sentence, or paragraph of this chapter or the application thereof to any person or circumstance shall be held invalid, such invalidity shall not affect the other provisions or application of the provisions of this chapter which can be given effect without the invalid provisions or application and, to this end, the provisions of this chapter are declared to be severable.
(Ord. 899 § 1, September 19, 1977; Ord. 1174 § 1, February 5, 2001)