Section 106-6 DEFINITIONS.

For the purposes of this ordinance, the following words and phrases shall have the meanings respectively ascribed to them by this subsection.

A. A-weighted sound level. The sound pressure level in decibels as measured on a sound level meter using the A-weighting network. The level so read is designated dB(a) or dBA.

B. Daytime. The local time of day between the hours of 7:00 A.M. and 10:00 P.M.

C. Decibel (dB). A unit for measuring the volume of a sound equal to twenty (20) times the logarithm to the base ten (10) of the ratio of the pressure of the sound measured to the reference pressure, which is twenty (20) micropascals (twenty micronewtons per square meter).

D. dBA shall mean the sound pressure level as measured on a sound meter set to slow response to the A-weighted scale to approximate the frequency response of the human auditory system.

E. Emergency work shall mean work made necessary to restore property to a safe condition following a public calamity, or work required to protect persons or property from immediate exposure to danger, including work performed by public service companies when emergency inspection, repair of facilities or restoration of services is required for the immediate health, safety or welfare of the community.

G. Noise shall mean any sound which may cause or tend to cause an adverse psychological or physiological effect on human beings.

H. Noise source shall mean any equipment, motor vehicle, motorcycle or facility, fixed or movable, capable of emitting sound beyond the property boundary of the property on which the equipment is used, but not including motor vehicles or motorcycles operated on public rights-of-way.

I. Sound. An oscillation in pressure, particle displacement, particle velocity or other physical parameter in a medium with internal forces that causes compression and rarefaction of that medium. The description of sound may include any characteristic of such sound including duration, intensity, and frequency.

J. Sound level. The weighted sound pressure level obtained by the use of an approved sound level meter and the A-frequency weighting network, as specified in American National Standards Institute specifications for sound level meters.

K. Sound level meter-shall mean an instrument to measure sound pressure levels which shall meet or exceed performance standards for a "type two" meter as specified by the American National Standards Institute.

L. Sound pressure shall mean the instantaneous difference between the actual pressure and the average or barometric pressure at a given point in space.