§ 130.22  DEFINITIONS.
   For the purpose of this subchapter, the following definitions shall apply unless the context indicates or requires a different meaning.
   AMBIENT SOUND LEVEL.  The all-encompassing noise associated with a given environment, being a composite of sounds from many sources, near and far. AMBIENT SOUND LEVEL is the average noise level excluding random or intermittent noises and excluding the alleged offensive noise.
   AMPLIFIED SOUND.  Any sound or noise, including the human voice, that is increased in volume or intensity by means of mechanical and / or electrical power.
   ANEMOMETER.  An instrument used to test and measure the wind speed, with an accuracy of +/- 10% at 20 mph.
   A-WEIGHTED SOUND LEVEL.  The sound level pressure level in decibels as measured on a sound level meter using the A-weighting network proscribed for sound level meters which is designed to reflect the acuity of the human ear. The level so read is designated dB(A) or dBA.
   A-WEIGHTING SCALE.  A sound filtering system contained in a sound meter that adjusts (weights) the incoming sound energy to approximate human hearing.
   CALIBRATOR.  A device used to standardize the reading of a sound meter or other device.
   CONSTRUCTION.  The erection, repair, assembly, alteration, landscaping, or demolition of any building or building site.
   CONTINUOUS NOISE.  A noise level that is without interruption in the same mode. Examples would be machinery such as a pump or blower. Sound measurements shall be made with the sound level meter using the A-weighting scale and on the slow response setting.
   DECIBEL OR DB(A).  A unit to measure the amplitude of sounds. As a sound measured in decibels increases, so does its loudness.
   FIELD CALIBRATION.  Calibration of the sound level meter using an external sound level calibrator for the purpose of ensuring the accuracy of sound level readings.
   IMPULSIVE NOISE.  A noise characterized by brief excursions of sound pressure whose peak levels are much greater than the ambient noise level, typically with short duration. Examples would be noise from a gunshot or firecracker. Sound measurements shall be made with the sound level meter using the A- weighting scale and on the fast response setting.
   INTERMITTENT NOISE.  A noise level that cycles or is discontinuous, or a noise level that increases and decreases. Examples would be noise from a passing airplane or vehicle. Sound measurements shall be made with the sound level meter using the A-weighting scale and on the fast response setting.
   MOTORIZED VEHICLE.  Any vehicle as defined in G.S. 20-4.01(49) including, but not limited to:
      (1)   Excursion passenger vehicles as defined in G.S. 20-4.01(27)a.
      (2)   Common carriers of passengers as defined in G.S. 20-4.01(27)c.
      (3)   Motorcycles and mopeds as defined in G.S. 20-4.01(27)d. and d.1.
      (4)   Truck tractors as defined in G.S. 20-4.01(48).
      (5)   Farm tractors as defined in G.S. 20-4.01(11).
   NOISE.  Any sound that annoys or disturbs humans or that causes or tends to cause an adverse psychological or physiological effect on humans.
   NOISE DISTURBANCE.  Any sound or noise which:
      (1)   Endangers or injures the health or safety of humans or animals;
      (2)   Endangers or injures personal or real property; or
      (3)   Disturbs a reasonable person of normal sensitivity or interferes with normal human activity.
   Except as otherwise provided herein, for purposes of this subchapter, a sound will be considered a NOISE DISTURBANCE if it exceeds the decibel level thresholds established by the sound level according to the  time of day.
   PERSON.  Any individual, association, firm, partnership, corporation, or business entity.
   REVOLUTIONS PER MINUTE (RPM).  The number of times the crankshaft of an engine revolves in 1 minute.
   SOUND.  Any disturbance of the air or other medium that is detectable by the unaided human ear or which produces vibrations detectable by reasonable persons of normal sensitivity.
   SOUND LEVEL METER.  An instrument that includes an omnidirectional microphone, a windscreen, an amplifier, an output meter, and frequency-weighting network for measurement of sound level, such as the A-weighting scale. A sound meter shall be a Type 1, Type S1A, Type 2 or Type S2A meter, meeting the standards specified by the ANSI S1.4-1983 (R2006). Sound meters shall be operated and calibrated as recommended by the manufacturer.
   STATIC OR STATIONARY NOISE LEVEL TEST.  Test levels are checked by utilizing a sound meter according to the methods and standards contained in this subchapter.
   TACHOMETER.  A device used to measure revolutions per minute (RPM) of an engine. TACHOMETERS may be permanently affixed to the vehicle, or may be portable units such as hand-held electric, vibrating reed, or inductive tachometers.
(2002 Code, Ch. 84, § 84.04)  (Ord. passed 6-23-2003; Am. Ord. passed 4-20-2004; Am. Ord. passed 7-19-2011)