7
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
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
PUH18EK
53
SPL(dB) 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 re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
SPL(dB) LINE
PUH24EK
PUH24EK1
55
90
80
70
60
50
40
30
20
10
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
63 125 250 500 1000 2000 4000 8000
BAND CENTER FREQUENCIES, Hz
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
SPL(dB) LINE
PUH30EK PUH36EK
PUH30EK
1 PUH36EK1
PUH30EK
2 PUH36EK2
55
Ambient temperature 80°F
Test conditions are based on JIS Z8731
3.3ft
3.3ft
MICROPHONE UNIT
GROUND
90
80
70
60
50
40
30
20
10
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
63 125 250 500 1000 2000 4000 8000
BAND CENTER FREQUENCIES, Hz
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
SPL(dB) LINE
PUH42EK PUH42EK7
PUH42EK1 PUH42EK71
56
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