[1]
Editor's Note: This Article was originally enacted 11-19-1968 effective 12-7-1968.
As used in this Article, the following terms shall have the meanings indicated:
AMBIENT NOISE
All-encompassing noise associated with a given environment.
BAND-PRESSURE LEVEL
The "band-pressure level" of a sound for a specified frequency band is the sound-pressure level for the sound contained within the restricted band. The reference pressure must be specified.
BEL
A unit of level when the base of a logarithm is 10, and is restricted to levels of quantities proportional to power.
CYCLE
The complete sequence of values of a periodic quantity that occur during a period.
DECIBEL
One-tenth of a bel, and is a unit of level when the base of the logarithm is the tenth root of 10 and the quantities concerned are proportional to power.
DURATION
The duration of a transient noise from a machine during the entire period when the transient noise is first distinguished from the ambient noise until the noise from the same machine finally recedes into the ambient noise shall be the period of time beginning when the transient noise first exceeds a certain band-pressure level until it no longer exceeds the same band-pressure level, provided that it remains above the same band-pressure level for at least 1/3 of the total duration.
FREQUENCY
The frequency of a function periodic in time is the reciprocal of the primitive period. The unit is the cycle per unit time and must be specified.
MICROBARS
A unit of pressure commonaly used in acoustics and is equal to one dyne per square cen-timeter.
NOISE
Any increase in the ambient noise, measured as provided in this Article, caused by any mechanical device, including aircraft.
PERSON
Any individual, firm, association or corporation, whether such person be the owner, lessee or charterer, his or its pilots or copilots, as to aircraft, and any individual, firm, association and corporation, its servants, agents or employees, as to any other sound-producing device or mechanism.
SOUND ANALYZER
A device for measuring the bandpressure level or pressure spectrum level of a sound as a function of frequency.
SOUND-LEVEL METER
An instrument, including a microphone, an amplifier, an output meter and frequency-weighting networks, for the measurement of noise and sound levels in the manner provided by this Article.
SOUND-PRESSURE LEVEL
The "sound-pressure level," in decibels, of a sound is 20 times the logarithm to the base 10 of the ratio of the pressure of this sound to the reference pressure, which reference pressure must be explicitly stated.
SPECTRUM
A function of time and is a description of its resolution into components, each of different frequency, and is also used to signify a continuous range of components usually wide in extent within which waves have some specified characteristics such as audio-frequency spectrum," and is also applied to functions of variables other than time.
STEADY NOISE
Any noise having a duration in excess of one minute, and the limits of Table II of this Article[1] shall apply.
TRANSIENT NOISE
Any noise having a duration of one minute or less, and the limits of Table I of this Article[2] shall apply.
[1]
Editor's Note: See § 144-5B.
[2]
Editor's Note: See § 144-5A.
No person shall operate or cause to be operated any mechanism or device, including but not limited to airplanes, which shall create a noise within the Town of Hempstead exceeding the limiting noise spectra set forth in Tables I and II, as follows:
A. 
Table I.
(1) 
Limiting noise spectrum for transient noise.
Band Pressure Level Decibels re 0.0002 Microbars
Octave Band Center Frequency
(cycles per second)
92
63
87
125
79
250
72
500
66
1,000
60
2,000
54
4,000
52
8,000
(2) 
During the daytime from 7:00 a.m. to 7:00 p.m., the limits of Table I hereinbefore set forth shall apply to transient noises having a duration in excess of 12 seconds. During the night, from 7:00 p.m. to 7:00 a.m., the same limits shall apply to transient noises having a duration in excess of six seconds.
B. 
Table II.
Limiting Noise Spectrum for Steady Noise
Band Pressure Level Decibels re 0.0002 Microbars
Octave Band Center Frequency
(cycles per second)
72
63
67
125
59
250
52
500
46
1,000
40
2,000
34
4,000
32
8,000
Noise measurements and limits shall conform to the following practices:
A. 
Noise shall be measured at an altitude not exceeding 100 feet above sea level.
B. 
Measurements of noise emanating from any mechanism or device, including but not limited to motor vehicles, shall be made at a distance of at least 100 feet from the longitudinal center line of the vehicle.
C. 
Machinery noise originating on private property shall be measured at the property line of the property on which the noise source is located.