8
NOISE CRITERIA CURVES
4
90
80
70
60
50
40
30
20
10
63
125
250
500
1000
2000
4000
8000
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCT
A
VE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
Test conditions,
Cooling : Dry-bulb temperature 27
:
Wet-bulb temperature 19
:
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
42
SPL(dB(A))
LINE
NOTCH
High
90
80
70
60
50
40
30
20
10
63
125
250
500
1000
2000
4000
8000
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCT
A
VE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
Test conditions,
Cooling : Dry-bulb temperature 27
:
Wet-bulb temperature 19
:
45
SPL(dB(A))
LINE
NOTCH
High
MS-C18TV -
E1
MS-C24TV -
E1
90
80
70
60
50
40
30
20
10
63
125
250
500
1000
2000
4000
8000
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCT
A
VE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
Test conditions,
Cooling : Dry-bulb temperature 35
:
Wet-bulb temperature 24
:
52
SPL(dB(A))
LINE
NOTCH
High
90
80
70
60
50
40
30
20
10
63
125
250
500
1000
2000
4000
8000
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCT
A
VE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
Test conditions,
Cooling : Dry-bulb temperature 35
:
Wet-bulb temperature 24
:
53
SPL(dB(A))
LINE
NOTCH
High
MU-C18TV -
E1
MU-C24TV -
E1
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