For use in this chapter, the following terms are defined:
1. “A-weighted sound level” means the sound pressure level in decibels as measured on a sound level meter using the A-weighting network. The level so read is designated dBA.
2. “Commercial” or “commercial district” means any property which is zoned for any commercial use as defined in the Zoning Ordinance, and on which there is no commercial use or residential use.
3. “Decibels” means a unit for measuring the volume of sound, equal to 20 times the logarithm to the base 10 of the ratio of the pressure of the sound measured to the reference pressure, which is 20 micropascals (20 micronewtons per square meter).
4. “Exhaust system” means the device or combination of devices that collects the exhaust from the engine or motor, delivers the exhaust to the atmosphere, and reduces the noise emissions. “Exhaust system” includes manifold or headers, exhaust pipe, muffler, and tail pipe.
5. “Gross vehicle weight rating” means the value specified by the manufacturer as the recommended maximum weighted load of a single motor vehicle. When trailers and tractors are separable, the gross combination weight rating is the value specified by the manufacturer as the recommended maximum loaded weight of the combined vehicle.
6. “Industrial” or “industrial district” means any property zoned for any industrial use as defined in the Zoning Ordinance, and on which there is no commercial use or residential use.
7. “Motor vehicle” means every vehicle which is self-propelled.
8. “Noise disturbance” means any transmission of sound across a real property boundary from a source specifically limited by this chapter, which exceeds the sound level limits set forth in Table 1 entitled “Maximum Permissible Sound Levels from Limited Sources by Receiving Land Use.”
9. “Real property boundary” means an imaginary line along the ground surface, and its vertical extension, which separates the real property owned by one person from that owned by another person, but not including intra-building real property divisions.
10. “Receiving land use” means the use or occupancy of the property which receives the transmission of sound.
11. “Residential” or “residential district” means any property on which is located a building or structure used wholly or partially for living or sleeping purposes. This definition does not include park custodial residences or school or college dormitories.
12. “Sound” means an oscillation in pressure, particle displacement, particle velocity or other physical parameter, in a medium with internal forces which cause compression and rarefaction of that medium. The description of sound may include any characteristic of sound, including duration, density, and frequency.
13. “Sound level” means the weighted sound pressure level contained by the use of the sound level meter and A-weighting network, such as a, b, or c as specified in American National Standards Institute Specification for Sound Level Meters, ANSI S1, 4-1971. If the frequency weighting employed is not indicated, the A-weighting shall apply.
14. “Sound level meter” means an instrument used to measure sound pressure.
15. “Sound pressure” means the instantaneous difference between the actual pressure and the average or barometric pressure at a given point in space, as produced by sound energy.
16. “Sound pressure level” means twenty times the logarithm to the base 10 of the ratio of the root mean squared sound pressure to the reference pressure of 20 micropascals.
17. “Used” or “occupied,” where either word appears, shall be deemed to include the words “intended, designed, or arranged to be used or occupied.”