07/2398 - Revised Noise Report and cover letters to referral agencies [As Published] · 132007.2398

RSL Care

Proposed RSL Retirement Village, Cooroy - Road and Rail Noise Assessment (Revised)

 

APPENDIX B: GLOSSARY OF ACOUSTIC TERMINOLOGY

A-Weighting

dB (decibel)

dB(A)

Facade Noise Level

Free Field

Hertz (Hz)

L

‘Aeq

Equivalent Continuous
Sound Level

bnso.r

bas 0,7

Lato, T

bwa

A response provided by an electronic circuit which modifies
sound in such a way that the resulting level is similar to that
perceived by the human ear.

This is the scale on which sound pressure level is expressed. It
is defined as 20 times the logarithm of the ratio between the
root-mean-square pressure of the sound field and the reference
pressure (0.00002N/m?).

This is a measure of the overall noise level of sound across the
audible spectrum with a frequency weighting (i.e. ‘A’ weighting)
to compensate for the varying sensitivity of the human ear to
sound at different frequencies.

Refers to a sound pressure level determined at a point close to
an acoustically reflective surface (in addition to the ground).
Typically a distance of 1 metre is used.

Refers to a sound pressure level determined at a point away
from reflective surfaces other than the ground with no significant
contribution due to sound from other reflective surfaces;
generally as measured outside and away from buildings.

A measure of the frequency of sound. It measures the number
of pressure peaks per second passing a point when a pure tone
is present.

This is the equivalent steady sound level in dB(A) containing the
same acoustic energy as the actual fluctuating sound level over
the given period. For a steady sound with small fluctuations, its
value is close to the average sound pressure level.

This is the dB(A) level exceeded 90% of the time, T.

This is the dB(A) level exceeded 10% of the time, T.

This is the dB(A) level exceeded 50% of the time, T.

The A-weighted sound power level in dB.

 

AIR NOISE ENVIRONMENT PTY LTD

INETWORK/PROJECTS/1750/REPORTING/2008 REVISION/17S0REPORTO4.ODT Page B1

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