Sound wave attenuation calculator (noise propagation)
Calculator finds out sound wave at given distance from source with given sound pressure level.

# Beta version#

BETA TEST VERSION OF THIS ITEM
This online calculator is currently under heavy development. It may or it may NOT work correctly.
You CAN try to use it. You CAN even get the proper results.
However, please VERIFY all results on your own, as the level of completion of this item is NOT CONFIRMED.
Feel free to send any ideas and comments !

# Calculation data: measured sound level and the distance#

 Measured data (what we know) Measured sound pressure level dB Distance to source, where we measured sound level yottameter [Ym]zettameter [Zm]exameter [Em]petameter [Pm]terameter [Tm]gigameter [Gm]megameter [Mm]kilometer [km]hektometer [hm]meter [m]decimeter [dm]centimeter [cm]milimeter [mm]micrometre (micron) [µm]nanometer [nm]pikometer [pm]femtometer [fm]attometer [am]zeptometer [zm]yoctometer [ym]statute leaguemile [mi]furlong [fur]surveyor's chain [ch]engineer's chain [ch]rod [rd]fathom [fm]yard [yd]foot [ft]link [li]handinch [in]lineparsec [pc]light year [ly]light minutelight secondastronomical unit [au]sea leaguesea mile [nmi]sea cabelbritish cabelUS cabelangstrom [Å] Prediction (what we want to know) The distance, where we want to predict sound level yottameter [Ym]zettameter [Zm]exameter [Em]petameter [Pm]terameter [Tm]gigameter [Gm]megameter [Mm]kilometer [km]hektometer [hm]meter [m]decimeter [dm]centimeter [cm]milimeter [mm]micrometre (micron) [µm]nanometer [nm]pikometer [pm]femtometer [fm]attometer [am]zeptometer [zm]yoctometer [ym]statute leaguemile [mi]furlong [fur]surveyor's chain [ch]engineer's chain [ch]rod [rd]fathom [fm]yard [yd]foot [ft]link [li]handinch [in]lineparsec [pc]light year [ly]light minutelight secondastronomical unit [au]sea leaguesea mile [nmi]sea cabelbritish cabelUS cabelangstrom [Å]

# Results - sound pressure level at given distance#

 Prediction (what we want to know) Sound level predicted at second distance 80dB

# Some facts#

• If we know the sound level measured at a certain distance from the source, then we can estimate sound level, that we would observe at a different distance:
$A(r) = A(r0) - 20 ~ log\left(\frac{r}{r_0}\right)$
where:
• $A(r)$ - sound level that would be observed at the distance $r$ from the source,
• $A(r_0)$ - known sound level measured at the distance $r_0$ from the source,
• $r$ - distance from the source at which we want to estimate the sound level $A(r)$,
• $r_0$ - distance from the source at which the reference intensity was measured $A (r_0)$ ,
• $log$ - base 10 logarithm.

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