8
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
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 µbar)
BAND CENTER FREQUENCIES, Hz
PMFY-P06NBMU-E
PMFY-P06NBMU-E1High
NOTCH
Medium1
Medium2
Low
35
SPL(dB)
33
30
27
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
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 µbar)
BAND CENTER FREQUENCIES, Hz
PMFY-P08NBMU-E
PMFY-P12NBMU-E
PMFY-P08NBMU-E1
PMFY-P12NBMU-E1
High
NOTCH
Medium1
Medium2
Low
37
SPL(dB)
36
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
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 µbar)
BAND CENTER FREQUENCIES, Hz
PMFY-P15NBMU-E
PMFY-P15NBMU-E1High
NOTCH
Medium1
Medium2
Low
39
SPL(dB)
37
35
33
LINE

UNIT

5ft

MICROPHONE

CEILING

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