15
4-4. 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
BAND CENTER FREQUENCIES, Hz
PMFY-P20VBM-E
PMFY-P20VBM-E
1
PMFY-P20VBM-E#2
PMFY-P20VBM-ER3
PMFY-P20VBM-ER4
High
NOTCH
Medium1
Medium2
Low
35
SPL(dB)
33
30
27
LINE
OCT
A
VE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002
μ
bar)
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
BAND CENTER FREQUENCIES, Hz
PMFY-P25/32VBM-E
PMFY-P25/32VBM-E
1
PMFY-P25/32VBM-E#2
PMFY-P25/32VBM-ER3
PMFY-P25/32VBM-ER4
High
NOTCH
Medium1
Medium2
Low
37
SPL(dB)
36
34
32
LINE
OCT
A
VE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002
μ
bar)
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
BAND CENTER FREQUENCIES, Hz
PMFY-P40VBM-E
PMFY-P40VBM-E
1
PMFY-P40VBM-E#2
PMFY-P40VBM-ER3
PMFY-P40VBM-ER4
High
NOTCH
Medium1
Medium2
Low
39
SPL(dB)
37
35
33
LINE
OCT
A
VE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002
μ
bar)
UNIT
1.5m
MICROPHONE
CEILING
OC307E
