All terminology used in this section shall be as defined herein or, if not defined, given plain meaning by reference to common dictionary definition. When interpretation is required by reference to a source more definitive than this code or a dictionary, reference shall first be made to publications of the American National Standards Institute (ANSI):
A-weighted sound level. The sound pressure level in decibels as measured on a sound level meter using the A-weighted network. The level so read is designated dBA.
Apparent property line. The line along the surface, and its vertical plane extension, which separates one (1) lot or parcel of property from another.
Construction. Any site preparation, assembly, erection, substantial repair, alteration or similar action, but excluding demolition, for or on public or private right-of-way, structures, utilities or similar property, and excluding well pointing.
Decibel (dB). A unit for measuring the volume of sound or noise, equal to twenty (20) times the logarithm to the base ten (10) of the ratio of the pressure of the sound or noise measured to the reference pressure, which is twenty (20) micropascals (twenty (20) micro-newtons per square meter).
Demolition. Any dismantling, intentional destruction or removal of structures, utilities, public or private right-of-way surfaces or similar property.
Emergency. Any occurrence or set of circumstances involving actual or eminent physical trauma or property damage which demands immediate action.
Emergency vehicle. A motor vehicle used in response to a public emergency or to protect persons or property from imminent danger.
Emergency work. Any work necessary to restore property to a safe condition following a public calamity, work to restore public utilities, or work required to protect person or property from an imminent exposure to danger.
Equivalent. The level of a constant sound, which in a given situation and time period, has the same sound energy as does a time varying sound.
Impulse noise. A discrete noise or series of such noises of short duration (generally less than one (1) second) in which the sound pressure level rises very quickly to a high before decaying to the background level. Examples of sources of impulse noise, includes explosions and the discharge of firearms.
L10 sound level. The sound level exceeded for more than ten (10) percent of a measurement period which for the purposes of sections 15-8 through 15-8.9
shall not be less than ten (10) minutes. LMAX. The maximum A-weighted sound level for a given event.
Legal holidays. Those recognized by the city include New Year’s Day, Martin Luther King, Jr. Day, Presidents Day, Memorial Day, Independence Day, Labor Day, Veterans Day, Thanksgiving Day, day after Thanksgiving, Christmas Eve, and Christmas Day or any other legally recognized holiday.
Maximum sound level. The greatest A-weighted sound level reading obtained when measuring a source of sound during a designated time interval using the fast meter exponential integration time.
Micropascal. The international unit for pressure, analogous to pounds per square inch in English units; one (1) microPascal is one millionth of a Pascal; the reference pressure used for airborne sound is twenty (20) microPascals.
Motorboat. Any boat or vessel propelled or powered by machinery whether or not such machinery is the principal source of propulsion; including but not limited to boats, barges, amphibious craft, water-ski towing devices, jet skis and hover craft.
Motorized equipment. Any self-propelled vehicle, such as, but not limited to, passenger cars, trucks, truck trailers, semi-trailers, campers, motorcycles, mini-bikes, go- carts, gopeds, dune buggies, all- terrain vehicles or racing vehicles which are propelled by mechanical power.
Multifamily dwelling. A building or other shelter that has been divided into separate units to house more than one (1) family.
Noise. For the purposes of this chapter, noise is any sound that is in violation of any provision of this chapter.
Noise disturbance. Any sound or noise, in quantities which are plainly audible and may be potentially harmful or injurious to human health or welfare, animal or plant life, or property, or unnecessarily interfere with the enjoyment of life or property, including outdoor recreation. Any plainly audible noise which is so harsh, prolonged, unnatural, or unusual in time or place as to occasion discomfort to any persons within the neighborhood and/or adjacent neighborhood(s) from which said noises emanate, or as to interfere with the peace and comfort of neighbors or their guests, or operators or customers in places of business, or as to negatively affect such residences or places of business.
Noise sensitive zone. Existing quiet zones until designated otherwise by a competent authority. Noise sensitive zones include but are not limited to operations of schools, libraries open to public, churches, synagogues, mosques, hospitals, residential zones (after 11:00 p.m.), and nursing homes.
Octave band sound level. The unweighted sound pressure level in the specified octave band.
Person. Any natural person, individual, association, partnership, corporation, municipality, governmental agency, business trust, estate, trust, two (2) or more persons having a joint or common interest or any other legal entity including any officer, employee, department, agency, or instrumentality of the United States, a state or any political subdivision of a state or any other entity whatsoever of any combination of such, jointly or severally.
Plainly audible. A sound which is capable of being heard by a human being without the assistance of a mechanical or electronic listening or amplifying device.
Powered model vehicle. Any self-propelled airborne, waterborne or landborne plane, vessel or vehicle which is not designed to carry persons, including but not limited to any model airplane, boat, car or rocket.
Private right-of-way. Any street, avenue, boulevard, highway, sidewalk, bike path, or alley, or similar place, which is not owned or controlled by a governmental entity.
Public right-of-way. Any street, avenue, boulevard, highway, sidewalk or alley or similar place normally accessible to the public which is owned or controlled by a governmental entity.
Public space. Any real property or structures thereon normally accessible to the public.
Pure tone. Any sound which can be distinctly heard as a single pitch or a set of single pitches. For the purpose 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 (2) contiguous one-third octave bands by five (5) dB for center frequencies of 500 Hz and above and by eight (8) dB for center frequencies between 160 and 400 Hz and by fifteen (15) dB for center frequencies less than or equal to 115 Hz.
Real property line. An imaginary line along the surface, and its vertical plane extension, which separates the real property owned, rented or leased by one person from that owned, rented or leased by another person, excluding intra-building real property divisions.
Receiving land use. The land, which is receiving the noise or sound as designated by the city zoning map (and for recently incorporated areas, the effective zoning category).
Residential. A parcel of land whose use is designated to provide only permanent housing and excluding all tourist accommodations which includes but is not limited to hotels, motels, apartment hotels, etc.
RMS sound pressure. The square root of the time averaged square of the sound pressure.
Sound. An oscillation in pressure, stress, particle displacement, particle velocity or other physical parameter, in a medium with internal forces. The description of sound may include any characteristic of such sound including duration, intensity and frequency.
Sound disturbance. Any sound or noise which is:
(1) Plainly audible beyond a distance of twenty-five (25) feet or further from the apparent property line from which the sound emanates, in a single residential zoning district, or
(2) Plainly audible in a dwelling unit adjacent to the unit from which the sound emanates or is plainly audible twenty-five (25) feet or further from the apparent property line from which the sound emanates, in multi-family residential zoning districts.
(3) Plainly audible beyond a distance of one hundred (100) feet or further from the apparent property line from which the sound emanates when the sound emanates in a commercial zoning district and is heard in a residential zoning district.
(4) Plainly audible beyond a distance of one hundred (100) feet or further from the apparent property line from which the sound emanates when the sound emanates in a public use zoning district and is heard in a residential zoning district.
For purpose of enforcement, it is not necessary to specifically identify the property line as would be depicted on a survey, rather an approximation of the property line may be used taking into consideration physical landmarks such as fences, landscaping, setbacks, driveways, or ground treatment.
Sound level. The weighted sound pressure level obtained by the use of a metering characteristic and weighting A, B, or C as specified in American National Standards Institute specification for sound level meters, ANSI S1.4-1971, or in successor publications. If the weighing employed is not indicated, the A-weighting shall apply.
Sound level meter. An instrument which includes a microphone, amplifier, RMS detector, integrator or time averager, output meter and weighing networks used to measure sound pressure levels. The output meter reads sound pressure levels when properly calibrated, and the instrument is of Type 2 or better, as specified in the American National Standards Institute Publication S1.4-1971, or its successor publications.
Sound pressure. 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.
Sound pressure level. 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 (2 x 106N/m2). The sound pressure level is denoted Lp or SPL and is expressed in decibels.
Use. Any activity, event, operation or facility which creates noise.
Weekday. Any Monday through Friday (at 6:00 p.m.) which is not a legal holiday as defined herein.
Weekend. Any Saturday or Sunday (until 8:00 p.m.).
(Ord. No. 85-16, § 2, 3-19-85; Ord. No. 86-3, § 1, 3-4-86; Ord. No. 11- 003, § 2, 2-15-11; Ord. No. 18-033, § 2, 12-4-18)
