OC196A-18
6. NOISE CRITERION CURVES
90
80
70
60
50
40
30
20
10
63
125
250
500
1000
2000
4000
8000
OCT
A
VE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
Hi
NOTCH
Lo
49
SPL(dB)
44
LINE
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
Hi
NOTCH
Lo
48
SPL(dB)
41
LINE
Wall
Unit
3.3ft
3.3ft
Ambient temperature 80˚F
Test conditions are based on JIS Z8731
PK18/24FK
PK18/24FK
1
PK18/24FK
2
90
80
70
60
50
40
30
20
10
63
125
250
500
1000
2000
4000
8000
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
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
Hi
NOTCH
Lo
45
SPL(dB)
38
LINE
PK12FK
PK12FK
1
PK30/36FK
PK30/36FK
1
PK30/36FK
2
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