§ 22.10.120. Noise Standards.

This Section establishes standards for acceptable exterior and interior noise levels and describe how noise shall be measured. These standards are intended to protect persons from excessive noise levels, which are detrimental to the public, health, welfare and safety and contrary to the public interest because they can: interfere with sleep, communication, relaxation and full enjoyment of one's property; contribute to hearing impairment and a wide range of adverse physiological stress conditions; and adversely affect the value of real property.

A.

Exceptions to noise standards. The standards of this Section are not applicable to noise from the following sources.

1.

Activities conducted in public parks, public playgrounds and public or private school grounds, including but not limited to school athletic and school entertainment events;

2.

The use of any mechanical device, apparatus or equipment related to or connected with emergency activities or emergency work to protect life or property;

3.

Safety signals, warning devices, and emergency pressure relief valves;

4.

Noise sources associated with construction, provided such activities do not take place before 7:00 a.m. or after 9:00 p.m. on any day except Saturday or Sunday, or before 8:00 a.m. or after 5:00 p.m. on Saturday or Sunday;

5.

Noise sources associated with the maintenance of a residential use as listed in Section 22.06.030 (Allowable Land Uses and Permit Requirements), provided that the activities take place between the hours of 7:00 a.m. and 9:00 p.m.;

6.

Noise sources associated with agricultural land uses as listed in Section 22.06.030 (Allowable Land Uses and Permit Requirements), including but not limited to wind machines used for direct climate control, water well pumps and pest-repelling devices, provided that the pest-repelling devices are used in accordance with accepted standards and practices.

7.

Noise sources associated with work performed by private or public utilities in the maintenance or modification of its facilities;

8.

Noise sources associated with the collection of waste or garbage from property devoted to other than residential uses listed in Section 22.06.030 (Allowable Land Uses and Permit Requirements).

9.

Traffic on public roadways, railroad line operations, aircraft in flight, and any other activity to the extent regulation thereof has been preempted by state or federal law.

B.

Exterior noise level standards. The exterior noise level standards of this Section are applicable when a land use affected by noise is one of the following noise-sensitive uses: residential uses listed in Section 22.06.030 (Allowable Land Uses and Permit Requirements), except for residential accessory uses and temporary dwellings; health care services (hospitals and similar establishments only); hotels and motels; bed and breakfast facilities; schools (pre-school to secondary, college and university, specialized education and training); churches; libraries and museums; public assembly and entertainment; offices, and outdoor sports and recreation.

1.

No person shall create any noise or allow the creation of any noise at any location within the unincorporated areas of the county on property owned, leased, occupied or otherwise controlled by the person which causes the exterior noise level when measured at any of the preceding noise-sensitive land uses situated in either the incorporated or unincorporated areas to exceed the noise level standards in the following table. When the receiving noise-sensitive land use is outdoor sports and recreation, the following noise level standards shall be increased by 10 dB.

Maximum Allowed Exterior Noise Level Standards
Sound levels	Daytime 7:00 a.m. to 10:00 p.m.	Nighttime (1) 10:00 p.m. to 7:00 a.m.
Hourly Equivalent Sound Level (L eq , dB)	50	45
Maximum level, dB	70	65

 

Notes:

(1)

Applies only to uses that operate or are occupied during nighttime hours.

2.

In the event the measured ambient noise level exceeds the applicable exterior noise level standard in Subsection B.1, the applicable standard shall be adjusted so as to equal the ambient noise level plus one dB.

3.

Each of the exterior noise level standards specified in Subsection B.1 shall be reduced by five dB for simple tone noises, noises consisting primarily of speech or music, or for recurring impulsive noises.

4.

If the intruding noise source is continuous and cannot reasonably be discontinued or stopped for a time period whereby the ambient noise level can be measured, the noise level measured while the source is in operation shall be compared directly to the exterior noise level standards.

C.

Interior noise level standards. The interior noise level standards of this Section are applicable when the land use which is the source of noise and the land use which is affected by noise are both residential uses as listed in Section 22.06.030 (Allowable Land Uses and Permit Requirements), except for residential accessory uses and temporary dwellings.

1.

No person shall operate or cause to be operated a source of noise within a residential use in any location in the unincorporated areas of the county or allow the creation of any noise which causes the noise level when measured inside a residential use located in either the incorporated or unincorporated area to exceed the interior noise level standards in the following table.

Maximum Allowed Interior Noise Levels
Sound levels	Daytime 7:00 a.m. to 10:00 p.m.	Nighttime 10:00 p.m. to 7:00 a.m.
Hourly Equivalent Sound Level (L eq , dB)	40	35
Maximum level, dB	60	55

 

2.

In the event the measured ambient noise level exceeds the applicable interior noise level standard in Subsection C.1, the applicable standard shall be adjusted so as to equal the ambient noise level plus one dB.

3.

Each of the interior noise level standards specified in Subsection C.1 shall be reduced by five dB for simple tone noises, noises consisting primarily of speech or music, or for recurring impulsive noises.

4.

If the intruding noise source is continuous and cannot reasonably be discontinued or stopped for a time period whereby the ambient noise level can be measured, the noise level measured while the source is in operation shall be compared directly to the interior noise level standards.

D.

Other noise sources. The noise level standards in this Section apply to the following.

1.

Air conditioning and refrigeration. Notwithstanding the provisions of Subsection B.1, when the intruding noise source is an air conditioning or refrigeration system or associated equipment installed prior to June 4, 1992, the exterior noise level as measured as provided in Subsection E. shall not exceed 55 dB, except where the equipment is exempt from the provisions of this Chapter. The exterior noise level shall not exceed 50 dB for equipment installed or in use after June 4, 1993.

2.

Waste and garbage collection equipment. Notwithstanding the provisions of Subsection B.1, noise sources associated with the collection of waste or garbage from a residential use (as listed in Section 22.06.030 (Allowable Land Uses and Permit Requirements) by persons authorized to engage in such activity, and who are operating truck-mounted loading or compacting equipment, shall not take place before 7:00 a.m. or after 7:00 p.m., and the noise level created by these activities when measured at a distance of 50 feet in an open area shall not exceed the following standards.

a.

85 dB for equipment in use, purchased or leased prior to December 4, 1992.

b.

80 dB for the equipment described in Subsection D.1 after June 4, 1997.

c.

80 dB for new equipment purchased or leased after December 4, 1992.

d.

75 dB for new equipment purchased or leased after June 4, 1995.

3.

Electrical substations. Notwithstanding the provisions of Subsection B.1, noise from the following electrical substations shall not exceed an exterior noise level of 50 dB between 10:00 p.m. and 7:00 a.m. and 55 dB between 7:00 a.m. and 10:00 p.m., as determined at the property line of the receiving land use: Cholame, San Miguel, Templeton, Cambria, Perry, Cayucos, Baywood, Highway 1 between Morro Bay and the California Men's Colony, Goldtree, Foothill, San Luis Obispo, Oceano, Mesa, Union Oil, Callendar, and Mustang. If any of these substations undergo modifications that increase noise levels, they shall be mitigated in compliance with the policies of the Noise Element Policy Document.

E.

Noise level measurement. For the purpose of evaluating conformance with the standards of this Chapter, noise levels shall be measured as follows.

1.

Use of meter. Any noise measurement in compliance with this Section shall be made with a sound level meter using the A-weighted network (scale). Calibration of the measurement equipment utilizing an acoustical calibrator shall be performed immediately prior to recording any noise data.

2.

Measuring exterior noise levels. Except as otherwise provided in this Section, exterior noise levels shall be measured at the property line of the affected noise-sensitive land use listed in Subsection B. Where practical, the microphone shall be positioned five feet above the ground and away from reflective surfaces.

3.

Measuring interior noise levels. Interior noise levels shall be measured within the affected residential use listed in Subsection C., at points at least four feet from the wall, ceiling or floor nearest the noise source, with windows in the normal seasonal configuration. The reported interior noise level shall be determined by taking the arithmetic average of the readings taken at the various microphone locations.

[Amended 1992, Ord. 2545] [22.06.040, 042, 044, 046, 048, 050]