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Function
Equation
Noise Dose
Using Exposure
Time
Dose
ET
(
)
Dose
MT
(
)
ET
MT
⋅
:=
ET is the Exposure Time in hours
MT is the Log Length (Measurement period) in hours
Noise Dose
per Hour
DoseHour
Dose
LogLength
:=
Log Length is the Measurement period in hours
Dose is the calculated Noise Dose determined over the
Log Length (Measurement period)
Sound
Exposure Level
L
AE
10 log
t1
t2
t
P
A
( )
2
t
( )
⌠
⌡
d
P
o
( )
2
T
o
⋅
dB
:=
L
AE
10 log
⋅
E
A
E
o
⋅
dB
:=
L
AE
L
AeqT
10 log
⋅
T
T
o
⋅
dB
⋅
+
:=
E
A
is the A-weighted sound exposure in Pascal-squared
hours
E
o
is the reference sound exposure of: -
20
µ
Pa
(
)
2
1s
(
)
⋅
400 10
12
−
⋅
Pa
2
s
:=
T
o
= 1s and T = t
2
-t
1
which is the time interval for
measurement, in seconds, for sound exposure level and
time-average sound level
L
AeqT
is the equivalent continuous A-weighted sound
pressure level (re 20 µPa) in dB
