§ 21-51. Definitions and standards.

[As used in this division the following words and terms shall have the meanings respectively ascribed:]

A-weighted sound 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 is designated dB(A) or dBA.

Daytime/evening shall mean the hours between six o'clock a.m. and ten o'clock p.m., Sunday through Thursday and six o'clock a.m. and eleven o'clock p.m. Friday and Saturday.

Director shall mean Director of Housing and Neighborhood Services Department.

Impulsive sound shall mean sound of short duration, usually less than one second, with an abrupt onset and rapid decay. Examples of sources of impulsive sound include explosions, drop forge impacts, and the discharge of firearms.

Leq shall mean an average measure of continuous noise that has the equivalent acoustic energy of the fluctuating signal over the same time period. The time period of monitoring will be continuous over any two (2) hours and will use the A-weighting network reported in decibel units.

Nighttime shall mean the hours between ten o'clock p.m. and six o'clock a.m., Sunday through Thursday and eleven o'clock p.m. and six o'clock a.m. Friday and Saturday.

Noise nuisance shall mean any loud, irritating, vexing or disturbing sound originating from a nearby property under separate ownership which causes injury, discomfort, or distress of a person of reasonable nervous sensibilities, or any sound that exceeds the maximum permitted sound levels specified in subsections 21-52(a) (6)(b), (9)—(12), and 21-60(b).

Sound level shall mean the weighted sound pressure level obtained by the use of a sound level meter and frequency weighting network such as A, B or C as specified in American National Standards Institute specifications for sound level meters (ANSI S1.4-1971). If the frequency weighting employed is not indicated, the A-weighting shall apply.

Sound level meter shall mean an instrument which includes a microphone, amplifier, RMS detector, integrator or time averages, output meter, and weighting network used to measure sound pressure levels.

(Ord. No. 94706, § 2(Attach. A), 9-13-01; Ord. No. 2007-04-05-0371, § 1, 4-5-07)