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8
3-3. NOISE CRITERION CURVES
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 (0 dB = 0.0002
µ
bar)
BAND CENTER FREQUENCIES, Hz
PCFY-P15NGMU-E
High
NOTCH
Medium1
Medium2
Low
38
SPL(dB)
36
33
29
LINE
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 (0 dB = 0.0002
µ
bar)
BAND CENTER FREQUENCIES, Hz
PCFY-P24NGMU-E
High
NOTCH
Medium1
Medium2
Low
39
SPL(dB)
37
34
32
LINE
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 (0 dB = 0.0002
µ
bar)
BAND CENTER FREQUENCIES, Hz
PCFY-P30NGMU-E
High
NOTCH
Medium1
Medium2
Low
43
SPL(dB)
41
38
36
LINE
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 (0 dB = 0.0002
µ
bar)
BAND CENTER FREQUENCIES, Hz
PCFY-P36NGMU-E
High
NOTCH
Medium1
Medium2
Low
44
SPL(dB)
42
39
37
LINE
UNIT
About 1.4m
MICROPHONE
CEILING
1m
1m
OC343A-1.qxp 06.8.2 11:31 AM Page 8