For the purpose of this subchapter, the following definitions shall apply unless the context clearly indicates or requires a different meaning.
AMBIENT NOISE. The all-encompassing noise associated with a given environment, being usually a composite of sounds from many sources near and far. For the purpose of this chapter, AMBIENT NOISE LEVEL is the level obtained when the noise level is averaged over a period of 15 minutes without inclusion of noise from isolated identifiable sources, at the location and time of day near that at which a comparison is to be made.
A-WEIGHTED SOUND PRESSURE LEVEL. The sound pressure level as measured with a sound meter using the "A"-weighting network. The standard notation is dBA.
COMMERCIAL PURPOSE. Includes the use, operation or maintenance of any sound amplifying equipment for the purpose of advertising any business, or any goods, or any services, or for the purpose of attracting the attention of the public to, or advertising for, or soliciting patronage or customers to or for any performance, show, entertainment, exhibition or event, for the purpose of demonstrating any such sound equipment.
COMMERCIAL ZONE. An area designated as neighborhood commercial (C-1), central business district (CBD), general commercial (C-2), or freeway commercial (FC) on the city zoning map.
CYCLICALLY VARYING NOISE. Steady or non-steady noise which varies in amplitude such that the same sound pressure level is obtained repetitively at reasonably uniform intervals of time. A beat is one class of noise.
DAY. The time period from 7:00 a.m. of one day to 10:00 p.m. of the same day.
DECIBEL (dB). A unit for expressing the ratio between two quantities of acoustical signal powers; the number of decibels corresponding to the ratio of two amounts of power is ten times the logarithm to the base ten of this ratio.
EMERGENCY WORK. Work made necessary to restore property to a safe condition following a public calamity, or work required to protect persons or property from an imminent exposure to danger, or work by private or public utilities when restoring utility service.
IMPULSIVE SOUND. A short-duration sound (such as might be produced by the impact of a drop hammer or a pile driver) with one second or less duration.
INDUSTRIAL ZONE. An area designated as commercial manufacturing (CM), office industrial (OI), industrial commercial (IC) or industrial (I) on the city zoning map.
MOTOR VEHICLES. Includes, but is not limited to, automobiles, trucks, motorcycles, mini bikes and go-carts.
NIGHT. The time period from 10:00 p.m. of one day to 7:00 a.m. of the following day.
NONCOMMERCIAL PURPOSE. The use, operation or maintenance of any sound equipment for other than a commercial use. NONCOMMERCIAL PURPOSE means and includes, but is not limited to, philanthropic, political, patriotic and charitable purposes.
PERSON. A person, firm, association, copartnership, joint venture, corporation, or any entity, public or private in nature, excluding the city.
PROPERTY BOUNDARY LINE. An imaginary line at the ground surface, which separates the real property owned by one person from that owned by another person and its vertical extension. This includes multiple-family dwelling units, with the property boundary being the wall separating the adjoining dwelling units.
PURE TONE. A sound wave whose instantaneous sound pressure varies essentially as a simple sinusoidal function of time.
RESIDENTIAL ZONE. An area designated as single family residential zone (R-I), residential garden (RG), or high-density multiple-family residential zone (R-3) on the city zoning map.
SOUND. The sensation perceived by the sense of hearing. For the purpose of this chapter, the terms sound and noise shall be used synonymously.
SOUND AMPLIFYING EQUIPMENT. Any device or equipment which amplifies the volume of any sound.
SOUND LEVEL (NOISE LEVEL). Expressed in decibels (dB) is the sound measured with the "A"-weight scale and with slow response by a sound level meter.
SOUND LEVEL METER. An instrument including a microphone, an amplifier, an output meter, and "A" frequency weighting networks for the measurement of sound levels, which satisfies the pertinent requirements in American Standard Specifications for Sound Level Meters SL4-1971 or the most recent revision thereof.
SOUND PRESSURE LEVEL. Twenty times the logarithm to the base ten of the ratio of the root-mean-square sound pressure to the reference pressure, which is 20 micronewtons per square meter.
SOUND TRUCK. Any motor vehicle or any other vehicle, regardless of motive power, whether in motion or stationary, which carries, is equipped with or which has mounted thereon, or attached thereto, any sound amplifying equipment for commercial, political or charitable purposes.
STEADY NOISE. Noise for which the sound pressure level remains essentially constant during the period of observation. It does not vary more than six dBA when measured with the slow meter characteristic of a sound level meter.
(Ord. 1114, passed 5-1-96; Am. Ord. 1388, passed 9-21-16)