500.05: REGULATIONS FOR NOISE — Porterville Municipal Code

A. Noise Exposure; Compatibility Criteria: In regard to noise exposure levels, land uses are classified as being either "normally compatible", "conditional" or "incompatible" as defined below. All land uses are compatible at noise exposure less than CNEL fifty five (55) dB.

Normally compatible:

a. Indoor Uses: Either the activities associated with the land use are inherently noisy or standard construction methods will

sufficiently attenuate exterior noise to an acceptable indoor community noise equivalent level (CNEL); for land use types that are compatible because of inherent noise levels, sound attenuation must be provided for associated office, retail, and other noise sensitive indoor spaces sufficient to reduce exterior noise to an interior maximum of CNEL fifty (50) dB.

b. Outdoor Uses: Except as noted in the table, activities associated with the land use may be carried out with minimal interference

from aircraft noise.

Conditional:

a. Indoor Uses: Building structure must be capable of attenuating exterior noise to the indoor CNEL indicated by the number in the

table cell.

b. Outdoor Uses: Caution shall be exercised with regard to noise sensitive outdoor uses; these uses are likely to be disrupted by

aircraft noise events; acceptability is dependent upon characteristics of the specific use. Noise sensitive land uses are ones for which the associated primary activities, whether indoor or outdoor, are susceptible to disruption by loud noise events. The most common types of noise sensitive land uses include, but are not limited to, the following: residential, hospitals, nursing facilities, intermediate care facilities, educational facilities, libraries, museums, places of worship, childcare facilities, and certain types of passive recreational parks and open space.

Incompatible:

a. Indoor Uses: Unacceptable noise interference if windows are open; at exposures above CNEL sixty five (65) dB, extensive

mitigation techniques required to make the indoor environment acceptable for performance of activities associated with the land use.

b. Outdoor Uses: Severe noise interference makes the outdoor environment unacceptable for performance of activities associated

with the land use.

B. Noise Exposure; Land Use Compatibility: Table 500.05B of this section describes the compatibility of various land uses within the noise impact zones as shown in section 500.10, map 500-1, "Airport Impact Map: Future Noise", of this article. Land uses not specifically listed in table 500.05B of this section shall be evaluated by the zoning administrator based on the criteria for the most similar comparable use.

The "conditional criteria" column lists the criteria to be met by uses listed as "conditional". The note numbers refer to criteria listed at the end of the table.

When a proposed building lies within multiple CNEL range zones (e.g., partly in 60 to 65 dB and partly in 65 to 70 dB), the higher range zone applies for the purposes of determining sound attenuation requirements unless less than twenty five percent (25%) of the building floor area is within that zone. In such case, the lower range zone may be used.

TABLE 500.05B: LAND USE COMPATIBILITY BY NOISE EXPOSURE LEVEL

NC = Normally compatible C = Conditional I = Incompatible Exterior Noise Exposure Conditional Land Use (CNEL dB) Criteria Exterior Noise Exposure (CNEL dB) Conditional Land Use 55 - 60 - 65 - 70 - 75 - Criteria 60 65 70 75 80 Outdoor uses (limited or no activities in buildings): Natural land areas: woods, brush NC NC NC NC NC See note 1 lands, desert Water: floodplains, wetlands, lakes, reservoirs Agriculture (except residences and livestock): crops, orchards, NC NC NC NC NC vineyards, pasture, rangeland

Livestock uses: feedlots, stockyards, breeding, fish C C C C I See note 2 hatcheries, horse stables Outdoor major assembly facilities (capacity 1,000 people): spectator oriented outdoor C C C I I See note 3 stadiums, amphitheaters, fairgrounds, zoos Group recreation (limited spectator stands): athletic fields, NC NC C I I See note 3 water recreation facilities, picnic areas Small/nongroup recreation: golf courses, tennis courts, shooting NC C C I I See note 3 ranges Local parks: children oriented neighborhood parks, NC C I I I See note 3 playgrounds Camping: campgrounds, recreational vehicle/motor home NC NC I I I parks Cemeteries (excluding chapels) NC NC NC NC I See note 4 Residential and lodging uses: Single-family residential: individual dwellings, townhouses, C, 40 C, 40 I I I See note 5 mobile homes, bed and breakfast inns Multi-family residential C, 40 C, 40 I I I See note 5 Long term lodging (>30 nights): NC C, 45 I I I extended stay hotels, dormitories Short term lodging (30 nights): hotels, motels, other transient lodging (except NC C, 45 I I I conference/assembly facilities)

Congregate care: retirement homes, assisted living, nursing homes, intermediate care facilities Educational and institutional uses: Family daycare homes (14 children) Children's schools: K - 12, daycare centers (>14 children); NC I I I I school libraries Adult education classroom space: adult schools, colleges, NC C, 45 C, 45 I I See note 6 universities Community libraries NC C, 45 I I I Indoor major assembly facilities (capacity 1,000 people): auditoriums, conference centers, NC C, 45 C, 45 I I concert halls, indoor arenas, casinos Indoor large assembly facilities (capacity 300 to 999 people): movie theaters, places of NC C, 45 C, 45 I I worship, cemetery chapels, mortuaries Indoor recreation: gymnasiums, clubhouses, athletic clubs, dance NC NC C, 50 I I studios Inpatient medical: hospitals, mental hospitals Outpatient medical: healthcare centers, clinics Penal institutions: prisons, reformatories

Public safety facilities: police, fire stations Commercial, office and service uses: Major retail: regional shopping centers, "big box" retail Local retail: community/neighborhood NC NC C, 50 I I shopping centers, grocery stores Eating/drinking establishments: restaurants, fast food dining, NC NC C, 50 I I bars Limited retail/wholesale: furniture, automobiles, heavy equipment, lumberyards, nurseries Offices: professional services, doctors, finance, civic; radio, television and recording studios, NC NC C, 50 I I office space associated with other listed uses Personal and miscellaneous services: barbers, car washes, NC NC C, 50 I I print shops Vehicle fueling: gas stations, trucking and transportation C, NC NC NC C, 50 terminals 50

Industrial, manufacturing, and storage uses: Hazardous materials production: NC NC NC NC NC oil refineries, chemical plants Heavy industrial NC NC NC NC NC Light industrial, high intensity: C, food products preparation, NC NC NC C, 50 50 electronic equipment Light industrial, low intensity: C, machine shops, wood products, NC NC NC C, 50 50 auto repair Research and development NC NC C, 50 C, 50 I Indoor storage: wholesale sales, warehouses, mini/other indoor NC NC NC NC NC storage, barns, greenhouses Outdoor storage: public works yards, automobile dismantling Mining and extraction NC NC NC NC NC Transportation, communication, and utilities: Airport terminals: airline, general aviation Rail and bus stations NC NC NC C, 50 I Transportation routes: road and rail rights of way, bus stops Auto parking: surface lots, structures Communications facilities: emergency communications, NC NC NC NC NC broadcast and cell towers Power plants NC NC NC NC NC Electrical substations NC NC NC NC NC Wastewater facilities: treatment, disposal Solid waste disposal facilities: NC NC NC NC NC landfill, incineration Solid waste transfer facilities, recycle centers

Notes:

Conditional Criteria:

Compatible at levels indicated, but noise disruption of natural quiet will occur.
Exercise caution with uses involving noise sensitive animals.
Exercise caution if clear audibility by users is essential.
Compatible at levels indicated, but noise disruption of outdoor activities will occur.
Only on existing residential parcels; no subdivisions are allowed.
Applies only to classrooms; offices, laboratory facilities, gymnasiums, outdoor athletic facilities, and other uses to be evaluated as indicated for those land use categories.

C. Single Event Noise Levels: Single event noise levels shall be considered when evaluating the compatibility of highly noise sensitive land uses such as residences, schools, libraries, and outdoor theaters. Susceptibility to speech interference and sleep disturbance are among the factors that make certain land uses noise sensitive. Single event noise levels are especially important in areas that are regularly overflown by aircraft, but that do not produce significant CNEL contours (helicopter overflight areas are a particular example). Flight patterns for Porterville Municipal Airport shall be considered in the review process. Acoustical studies or on site noise measurements may be required to assist in determining the compatibility of sensitive uses.

D. Maximum Acceptable Interior Noise Levels: Land uses for which interior activities may be easily disrupted by noise shall comply with the following maximum, aircraft related, interior noise level criteria:

CNEL forty (40) dB in any habitable room of single- or multi- family residences.
CNEL forty five (45) dB for: hotels, motels, and other lodging; hospitals and nursing homes; places of worship, meeting halls,

theaters, and mortuaries; and schools, libraries, and museums.

CNEL fifty (50) dB in offices and office areas of industrial facilities.

E. Residential Interior Noise Level Reduction: New dwellings exposed to CNEL above sixty (60) dB shall incorporate the following noise reduction design measures unless alternative designs that achieve and maintain an interior noise level of CNEL forty (40) dB are incorporated and verified by a board certified acoustical engineer:

All facades must be constructed with substantial weight and insulation;
Sound rated windows providing noise reduction performance similar to that of the facade must be included for habitable rooms;
Sound rated doors or storm doors providing noise reduction performance similar to that of the facade must be included for all

exterior entries;

Acoustic baffling of vents is required for chimneys, fans, and gable ends;
Installation of a mechanical ventilation system affording comfort under closed window conditions; and
Double stud construction, double doors, and heavy roofs with ceilings of two (2) layers of gypsum board on resilient channels.

(Ord. 1801, 12-3-2013)