Terminology

Acoustic

Studies the generation, propagation and detection of acoustic phenomena.

Acoustic barrier

A sound barrier is a device used to reduce noise transmission along a certain direction. It is interposed in the path of sound propagation by air between the source and the presence ricevitore.La soil affects the propagation of sound outdoors due to interference between the reflected sound from the ground and the sound transmitted by air . The resulting attenuation depends on the extent of the source and the receiver and the surface characteristics of the soil.

Sound Field

Set of points of the propagation medium affected by the phenomenon of sound. Knowledge at every point of the acoustic quantities.

Decibels dB (A)

E 'in the relationship between the logarithmic sound pressure and sound pressure corresponding to the minimum threshold of audibility. You specify dB (A) when the monitoring was carried out taking into account the human ear and then a second weighting.

Acoustic phenomena

Oscillatory phenomena that propagate in a medium elastico.FonoassorbenteSi said of a material able to absorb the propagation of sound waves thereby reducing noise.

LEQ

E 'Level eqivalent, which is the value, expressed in decibels, a sound that has the same sound energy measured at a specific time interval. It is said when the LAeq level equivalent refers to a noise-weighted A.

LVA

E 'index for assessment of airport noise. It is obtained from equations based on the Single Event Level (SEL) of noise, that sounds just about related to a specific source, just as the air traffic.

Sound Source

Vibrating body elastic medium which transmits the stress of time-varying pressure assigned by law. The sound source gives rise to a succession of compressions and rarefactions of the air layers adjacent to it, and then generates pressure oscillations that propagate as waves. The transmission of mechanical vibration from the sound source to the medium generates an energy transfer from the source to the medium itself through the waves.

Sound

Oscillatory phenomenon capable of generating a sensation in humans. These phenomena have a frequency between 20 Hz and 20 kHz (sound). The subjective feeling is caused by fluctuations in ambient air pressure around the atmospheric pressure.

Volume

The volume is determined by the sound wave exerts pressure on the eardrum of the man who hears such a sound. The sound wave in turn is determined by the amplitude of the vibration and the distance between the point of emission of sound and that of perception.