Definitions. Unless the context clearly indicates otherwise, the
words and phrases used in this section are defined as follows:
A BAND LEVEL
The total sound level of all noise as measured with a sound
level meter using "A" weighting network. The unit is the dbA.
AMBIENT NOISE
The all-encompassing noise associated with a given environment,
usually being a composite of sounds with many sources near and far.
BAND-PRESSURE LEVEL
The sound-pressure level for the sound contained within the
restricted band.
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,
or for the purpose of demonstrating any such sound equipment, or for
the purpose of entertaining customers and occupants of taverns and
other places of commercial business.
CYCLE
The complete sequence of values of a periodic quantity which
occurs during a period.
DECIBEL
A unit used to express the ratio of two values of a physical
quantity which are proportional to power; the number of decibels corresponding
to the ratio of two amounts of power is 10 times the logarithm to
the base 10 of this ratio.
FREQUENCY
The reciprocal of the primitive period. The unit is the cycle
per unit time and shall be specified.
MICROBAR
A unit of pressure commonly used in acoustics and is equal
to one dyne per square centimeter.
NONCOMMERCIAL PURPOSE
The use, operation or maintenance of any sound equipment
for other than a commercial purpose. "Noncommercial purpose" shall
mean and include, but shall not be limited to, philanthropic, political,
patriotic and charitable purposes.
PERIOD
The smallest increment of time for which the function repeats
itself.
PERIODIC QUANTITY
Oscillating quantity, the values of which recur for equal
increments of time.
SOUND ANALYZER
A device for measuring the band pressure level or pressure
spectrum level of sound as a function of frequency.
SOUND TRUCK
Any motor vehicles or any other vehicle regardless of motive
power, whether in motion or stationary, having mounted thereon, or
attached thereto, any sound-amplifying equipment.
SOUND-AMPLIFYING EQUIPMENT
Any machine or device for the amplification of the human
voice, music or any other sound. Sound-amplifying equipment shall
not include standard automobile radios when used and heard only by
the occupants of the vehicle in which the automobile radio is installed.
Sound-amplifying equipment, as used in this section, shall not include
warning devices or authorized emergency vehicles or horns or other
warning devices on any vehicle used only for traffic safety purposes.
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 a specified manner.
SOUND-PRESSURE LEVEL
Twenty times the logarithm to the base 10 of the ratio of
the pressure of this sound to the reference pressure, which reference
pressure shall be explicitly stated.
SPECTRUM
A description of its resolution into components, each of
a different frequency.