For the purpose of this chapter, the following definitions shall apply unless the context clearly indicates or requires a different meaning. All terminology used in this chapter and not defined below shall be in conformance with applicable publications of the American National Standards Institute (ANSI) or its successor body.
AMBIENT NOISE LEVEL. The sound pressure level of the all encompassing noise associated with a given environment, being usually a composite of sounds from many sources.
A-WEIGHTED SOUND PRESSURE LEVEL. The sound pressure level as measured on a sound level meter using the A-weighting network. The level so read shall be designated dB(A) or dBA.
CONTINUOUS NOISE. A steady, fluctuating or impact noise which exists essentially without interruption for a period of one hour or more.
CYCLICALLY VARYING NOISE. Steady, fluctuating or impulsive noise which may or may not contain a pure tone and which varies in sound pressure level such that the same level is obtained repetitively at reasonably uniform intervals of time.
DECIBEL. A logarithmic (dimensionless) unit of measure often used in describing the amplitude of sound. DECIBEL is denoted as dB.
DEPARTMENT. The County Department of Health or any municipal agency related to the noise control programs such as the Board of Health, the Community Development Department and the Police Department.
DEVICE. Any mechanism which is intended to produce or which actually produces noise when operated or handled.
EMERGENCY VEHICLE. A motor vehicle used in response to a public calamity or to protect persons or property from imminent danger.
EMERGENCY WORK. Work made necessary to restore property to a safe condition following a public calamity, work to restore public utilities or work required to protect persons or property from an imminent exposure to danger.
FLUCTUATING NOISE. When the sound pressure level of a fluctuating noise varies more than 6 dB(A) during the period of observation, when measured with the slow-meter characteristic of a sound level meter, and does not equal the previously existing ambient noise level more than once during the period of observation.
IMPULSIVE NOISE. A noise characterized by brief excursions of sound pressure whose peak levels exceed the ambience by 10 dB. The duration of a single impulse is usually less than one second and requires the use of a sound level meter specially adapted for its measurement.
MOTOR VEHICLE. As defined in the Motor Vehicle Code of the state or any vehicles which are propelled or drawn by mechanical equipment, such as, but not limited to, passenger cars, trucks, truck-trailers, semitrailers, campers, motorcycles, minibikes, go-carts, snowmobiles, amphibious craft on land, dune buggies or racing vehicles.
MUFFLER. Any apparatus whose primary purpose is to transmit liquids or gases while causing a reduction in sound emission at one end.
NOISE. Any sound which is unwanted or which causes or tends to cause an adverse physiological or psychological effect on human beings.
NOISE DISTURBANCE. Any sound which annoys, disturbs or perturbs reasonable persons with normal sensitivities or any sound which injures or endangers the comfort, repose, health, hearing, peace or safety of other persons.
PERSON. Any individual, association, partnership or corporation, public or private.
PLAINLY AUDIBLE NOISE. Any noise for which the information content of that noise is unambiguously communicated to the listener, such as, but not limited to, understandable spoken speech or comprehensible musical rhythms.
POWERED MODEL VEHICLES. Any powered vehicles, either airborne, waterborne or landborne, which are designed not to carry persons or property, such as, but not limited to, model airplanes, boats, cars, rockets and which can be propelled by mechanical means.
PROPERTY BOUNDARY. An imaginary line at the ground surface, and its vertical extension, which separates the real property owned by one person from that owned by another person.
PUBLIC RIGHT-OF-WAY and PUBLIC SPACE. Any street, avenue, boulevard, highway, alley or public space which is owned or controlled by a public government entity.
PURE TONE. Any noise which can be distinctly heard as a single pitch or a set of single pitches. For the purposes of measurement, a “pure tone” shall exist if the one-third octave band sound-pressure level in the band with the tone exceeds the arithmetic average of the sound pressure levels of the two contiguous one-third octave bands by 5 dB for frequencies of 500 hertz and above by 8 dB for frequencies between 160 and 400 hertz and 15 dB for frequencies less than or equal to 125 hertz.
REPETITIVE IMPULSIVE NOISE. Repetitive noise which is composed of impulsive noises that are repeated at sufficiently slow rates such that a sound level meter set at a fast-meter characteristic will show changes in sound pressure level greater than 2 dB(A).
RMS SOUND PRESSURE. The square root of the time averaged square of the sound pressure, denoted Prms.
SOUND. A temporal and spatial oscillation in pressure, or other physical quantity, in a medium with internal forces, that causes compression and rarefaction of that medium and which propagates at finite speed to distant points.
SOUND LEVEL METER. An instrument, including a microphone, amplifier, RMS detector and integrator or time averager, output meter and weighting networks, used to measure these sound pressure fluctuations. For enforcement of this chapter, the “sound level meter” (Model 215-4512 AM) of Quest Electronics, Oconomowoc, Wisconsin, shall be used unless the Noise Control Officer otherwise approves usage of any other “sound level meter.”
SOUND PRESSURE. The instantaneous difference between the actual pressure and the average or barometric pressure at a given point in space.
SOUND PRESSURE LEVEL. Twenty times the logarithm to the base 10 of the ratio of the RMS sound pressure to the reference pressure which shall be 20 micropascals, denoted Lp or SPL.
STATIONARY EMERGENCY SIGNALING DEVICES. Any device, excluding those attached to motor vehicles, used to alert persons engaged in emergency operations. These include, but are not limited to, fire fighters, first-aid squad members and law enforcement officers, whether paid or volunteer.
STATIONARY NOISE SOURCE. Any device, fixed or movable, which is located or used or geographically defined, real property other than a public right-of-way.
STEADY NOISE. A sound pressure level which remains essentially constant during the period of observation, i.e., the fluctuations are too small to meet the criterion for fluctuating noise.
VIBRATION. A temporal spatial oscillation of displacement, velocity or acceleration in a solid material.
WEEKDAY. Any Monday, Tuesday, Wednesday, Thursday or Friday which is not a legal holiday.
('74 Code, § 89-3) (Ord. 259-1985, passed 1-14-85)