§ 13-5. Terminology, standards, and definitions.
(a)
Terminology and standards. All technical acoustical terminology and standards used in this chapter which are not defined in subsection (b) shall be read or construed in conformance with the American National Standards Institute, Inc. ("ANSI") publication entitled "Acoustical Terminology," designated as ANSI S1.1-1960, or its successor publication.
(b)
Definitions. The following words, terms and phrases, when used in this chapter, shall have the meanings ascribed to them in this section, unless the context clearly indicates a different meaning:
(1)
A-weighted sound pressure level shall mean the sound pressure level, in decibels, as measured on a sound level meter using the A-weighting network. The level so read shall be designated as dB(A).
(2)
Ambient sound level or background sound level shall mean the background sound pressure level at a given location, normally specified as a reference level to study a new intrusive sound source. Ambient sound levels may be measured to provide a reference point for analyzing an intrusive sound to a given environment.
(3)
ANSI shall mean the American National Standards Institute.
(4)
Construction shall mean any site preparation, assembly, erection, substantial repair, alteration, or similar action, for or on public or private thoroughfares, structures, utilities or similar property.
(5)
Decibel or dB shall mean a unit for describing the amplitude of sound, equal to twenty (20) times the logarithm to the base 10 of the ratio of the pressure of the sound measured to the reference pressure, which is twenty (20) micropascals per square meter.
(6)
Demolition shall mean any dismantling, destructing or razing of structures, utilities, public or private thoroughfares, or similar property.
(7)
Emergency shall mean any occurrence or circumstance involving actual or imminent physical death or trauma, or property damage, demanding immediate emergency work or service.
(8)
Emergency work or emergency service shall mean any labor performed for the purpose of preventing or alleviating, or attempting to prevent or alleviate, an emergency.
(9)
Equivalent sound pressure level (Leq) shall mean a sound level descriptor based on the average acoustic intensity over time. Leq is intended as a single number indicator to describe the mean energy or intensity level over a specified period of time during which the sound level fluctuated. Leq is measured in dB and must be A-weighted.
(10)
Leq, see definition for "equivalent sound pressure level."
(11)
Motor vehicle shall mean any vehicle defined as "motor vehicle" by F.S. § 320.01(1).
(12)
Multifamily residential dwelling shall mean a building designed or used exclusively for residential occupancy by two (2) or more families.
(13)
Multifamily residential dwelling unit shall mean the portion of a multifamily residential dwelling designed or used exclusively for residential occupancy by only one family.
(14)
Noise shall mean any sound produced in such quantity and for such duration that it annoys, disturbs or may injure a man or woman of normal sensitivities.
(15)
Noise-sensitive zone shall mean a quiet zone where serenity and quiet are of extraordinary significance, which is open or in session, and which is demarcated by conspicuous signage identifying it as a noise-sensitive or quiet zone. Noise-sensitive zones may include schools, public libraries, churches, hospitals, nursing homes, and other areas defined as such pursuant to a resolution adopted by the board of county commissioners.
(16)
Person shall mean an individual, association, partnership, or corporation, including any officer, employee, department, agency or instrumentality of the United States, the state or any political subdivision thereof.
(17)
Plainly audible means any electronically amplified music or sound that can be clearly heard by an officer using his normal hearing faculties not enhanced by any device such as a microphone or hearing aid. Where distance measurements are required by this section to determine whether sound is plainly audible for purposes of this article, measurements shall be taken in accordance with the following requirements:
a.
The officer must have a direct line of sight to the relevant location (i.e., the location of the noise, real property line, or motor vehicle), so that the officer can readily identify the distance involved.
b.
The officer need not determine the particular words or phrases being produced or the name of any song or artist producing the sound. The detection of a rhythmic bass reverberating type sound is sufficient to constitute a plainly audible sound.
(18)
Public right-of-way shall mean any street, avenue, boulevard, highway, sidewalk, alley, or similar place normally accessible to the public which is owned or controlled by the county.
(19)
Pure tone shall mean any sound which can be distinctly heard as a single pitch or a set of single pitches.
(20)
Real property line means either: (i) the imaginary line including its vertical extension that separates one parcel of real property from another; or (ii) the vertical and horizontal boundaries of a dwelling unit that is part of a multifamily dwelling unit such as a condominium, townhouse or apartment building.
(21)
Residential areas means recorded and unrecorded subdivisions and those areas in which there is a concentration of residential dwelling units on lots or tracts of less than five (5) acres.
(22)
RMS sound pressure shall mean the square root of the time averaged square of the sound pressure.
(23)
Single-family residential dwelling shall mean a detached dwelling containing complete housekeeping facilities for only one family, designed for or occupied exclusively by one family for usual domestic purposes, and having no enclosed space or cooking facilities or sanitary facilities in common with any other dwelling.
(24)
Single-family residential dwelling lot shall mean the parcel of land upon which a single family residential dwelling is located.
(25)
Sound shall mean an oscillation in pressure, stress, particle displacement, particle velocity or other physical parameter, in a medium (typically air). The description of sound may include any characteristic of such sound, including duration, intensity, and frequency.
(26)
Sound level shall mean the sound pressure level obtained by the use of a sound level analyzer using weighting A, B, or C as specified in American National Standards Institute specifications for sound level analyzers (ANSI S1.4-1971), or successor publications. If the weighting employed is not indicated, the A-weighting shall apply.
(27)
Sound level analyzer shall mean an instrument which includes a microphone, amplifier, RMS detector, integrator or time averager, output meter, and weighting network used to measure sound pressure levels. The output analyzer reads sound pressure level when properly calibrated. The sound level analyzer shall be of Type 2 or better, as specified in the American National Standards Institute publication entitled "Specifications for Sound-Level Meters," designated as ANSI S1.4-1971 or successor publications.
(28)
Sound pressure shall mean the instantaneous difference between the actual pressure and the average or barometric pressure at a given point in space, as produced by the presence of sound energy.
(29)
Sound pressure level shall mean twenty (20) times the logarithm to the base ten (10) of the ratio of the RMS sound pressure to the reference pressure of twenty (20) micropascals per square meter. The sound pressure level is denoted Lp (or SPL) and is expressed in decibels.
(30)
Vibration measuring device (VMD) means a three (3) component vibration measuring device.
(31)
Vibration shall mean a periodic motion of the particles of an elastic body or medium in alternatively opposite directions from the position of equilibrium when that equilibrium has been disturbed; the action of vibrating; the state of being vibrated. As applied in this chapter shall mean ground-borne vibration.
(Ord. No. 99-2, § 1, 1-19-99; Ord. No. 15-08, § 1, 6-16-2015)