§ 22-36. Airport noise abatement.

Airport noise control requirements for buildings constructed in the unincorporated portions of Sarasota County in the vicinity of the Sarasota-Bradenton Airport.

(a)

Airport noise control. It is the intent of this section to establish sound isolation requirements for exterior walls, roofs, doors, windows, and sloped glazing on buildings constructed within Airport Noise Contours established by the Sarasota-Manatee Airport Authority. Due to the conditions existing within the Airport Noise Contours, it is necessary to adopt insulation requirements for these areas which are more stringent than those required by the Florida Building Code.

(b)

Noise contour map. This section adopts by reference the Airport Noise Contour Map prepared by the Sarasota-Manatee Airport Authority titled "Sarasota County, SRQ Part 150 Implementation." One copy of the Airport Noise Contour Map will be kept on file with the Clerk of Court in the Board Records Office and three copies of the map will be kept on file in the permitting and inspections operations facility.

(c)

Definitions. For the purposes of this section, the following terms shall have the meanings set forth herein unless the context clearly indicates otherwise.

(1)

Aircraft Noise Reduction means the difference between aircraft sound level inside and outside of a building space.

(2)

Airport Noise Contours means contours drawn around the active or planned future runways of an airport, based on the Ldn or equivalent noise estimating methodology, which contours establish the noise impact areas of the airport.

(3)

Day-Night Average Sound Level (Ldn) means a 24-hour energy average sound level expressed in dBA, with a ten decibel penalty applied to noise occurring between 10:00 p.m. and 7:00 a.m.

(4)

dBA means a unit of corrected sound level measured in decibels on the A scale of the sound level meter providing a measurement of sound in accordance with levels actually heard by the ear.

(5)

Decibel (dB) means a unit for measuring the relative intensity 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 referenced pressure, which is twenty micropascals (twenty micronewtons per square meter). In terms of human perceptions of continuous sound, a three dB change is clearly perceptible; a ten dB change is perceived as a doubling or halving of loudness.

(6)

Noise Impact Areas means those areas in the vicinity of an airport, as shown on a noise contour map, which are impacted by noise from aircraft operations of an airport.

(d)

Performance standards. The sound isolation requirements specified herein are stated in terms of three classes of aircraft noise reduction. These classes are defined in terms of the following interior noise levels.

(1)

Thirty-five Ldn Reduction. Sound isolation adequate to limit an interior noise level so that it does not exceed 45 Ldn in buildings located within the 75 Ldn noise contour.

(2)

Thirty Ldn Reduction. Sound isolation adequate to limit an interior noise level so that it does not exceed 50 Ldn in buildings located within the 75 Ldn noise contour, and an interior noise level that does not exceed 45 Ldn in buildings located between the 70 and 75 Ldn noise contours.

(3)

Twenty-five Ldn Reduction. Sound isolation adequate to limit an interior noise level so that it does not exceed 50 Ldn in buildings located between the 70 and 75 Ldn noise contours, and an interior noise level that does not exceed 45 Ldn in buildings located between the 65 and 70 Ldn noise contours.

(e)

Sound isolation requirements.

(1)

Exterior walls, roofs, doors, windows, and sloped glazing located in the Airport Noise Impact Contour Areas shall have acoustical characteristics which provide the noise level standards listed below in Table 1.

TABLE 1. NOISE LEVEL STANDARDS

Occupancy	75 Ldn	70 Ldn	65 Ldn
GROUP A
Amusement Park Buildings, Auditoriums, Churches, Dance Halls, Gymnasiums, Restaurants, Motion Picture Theaters, Museums, Passenger Depots, Public Assembly Halls, Recreation Halls, Theaters for Stage Production	35	30	25
Stadiums and Grandstands	NSR	NSR	NSR
Tents for Assembly	NSR	NSR	NSR
Other	35	30	25
GROUP B
Animal Hospitals, Kennels, Pounds, Automobile Showrooms, Banks, Barber Shops, Beauty Shops, Car Wash, Civic Administration, Dry Cleaning, Electronic Data Processing, Florist and Nurseries, General Post Offices, Greenhouses, Laundries, Office Buildings, Police Stations, Print Shops, Professional Services, Radio & TV Stations, Telephone Exchanges	35	30	NSR
Bowling Alleys, Clinic Outpatient, Laboratories	35	30	25
Educational Occupancies above the 12th Grade, Libraries (other than school)	35	30	25
Other	35	30	NSR
GROUP E and I
Educational Purposes through the 12th Grade, Child Care Facilities, Medical, Surgical, Psychiatric, Nursing or Custodial Care on a 24-Hour Basis, Hospitals, Nursing Homes, Detoxification Facilities, Vocational Schools, Business Schools	35	30	25
Other	35	30	25
GROUP M
Department Stores, Drug Stores, Markets, Retail Stores, Shopping Centers, Sales Rooms, Wholesale Stores (other than warehouses)	35	30	NSR
Other	35	30	NSR
GROUP R
Hotels and Motels, Boarding Houses (transient), Apartment Houses, Boarding Houses (not transient), Convents, Fraternities and Sororities, Monasteries, Dormitories, One-and Two-Family Dwellings	35	30	25
Manufactured Home Parks, RV Parks or Camping Areas	35	30	25
Other	35	30	25

 

Note:  No Special Requirements

(2)

Compliance with the aircraft sound isolation performance standards shall be established by certification from a registered professional architect or engineer that when constructed in accordance with the approved plans, the building shall achieve the specified interior noise levels, or by the use of assemblies having the Sound Transmission class ratings specified below in Table 2.

TABLE 2. MINIMUM SOUND TRANSMISSION OF ASSEMBLIES

% Openings	Noise Reduction	Exterior Walls and Walls	Exterior Doors, Windows and Sloped Glazing
1—25%	35 Ldn	50	42
	30 Ldn	45	37
	25 Ldn	39	28
26—70%	35 Ldn	55	45
	30 Ldn	50	31
	25 Ldn	45	37

 

(f)

Applicability.

(1)

This section shall be applicable to all new and existing buildings being substantially improved within the 65 Ldn contour line as shown on the Noise Contour Map.

(2)

"Substantially Improved" means any repair, reconstruction, or improvement of a building, the cost of which equals or exceeds 50 percent of the market value of the building either prior to the commencement of the improvement or prior to the commencement of repair or reconstruction.

(3)

For the purpose of this section, substantial improvement is considered to occur when the first alteration of any wall, ceiling, floor, or other structural part of the building commences, whether or not that alteration affects the external dimensions of the building.

Substantial improvement does not include any project for improvement of a building to comply with Federal, State, or Local health, sanitary, or safety codes which are solely necessary to assure safe living conditions or any alteration of a structure listed on the National Register of Historic Places or a State Inventory of Historic Places.

(g)

The Building Official is authorized to grant an exception to the requirements of this section for replacement manufactured homes and park trailers when the applicant for a building permit:

(1)

Demonstrates that the replacement manufactured home or park trailer is located in a manufactured home or recreational vehicle park existing on January 1, 2001; and

(2)

Provides a notarized Owner Affidavit acknowledging that the manufactured home or park trailer does not comply and cannot be practicably modified to comply with the sound isolation requirements of this section.

(Ord. No. 98-013, § 6, 2-17-1998; Ord. No. 2000-053, § 6, 7-25-1998; Ord. No. 2001-035, § 2, 5-23-2001; Ord. No. 2004-030, § 1, 3-17-2004)

Cross reference

Noise, § 54-151 et seq.