7
NOISE CRITERIA CURVES
3
MSH-C18SV -
E1
MUH-C12SV -
E1
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
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
Test conditions, Cooling : DB 27: WB 19:
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
COOLING
FUNCTION
42
SPL(dB(A)) LINE
Hi
NOTCH
HEATING
Heating : DB 20: WB - :
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
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
Test conditions, Cooling : DB 35: WB 24:
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
COOLING
FUNCTION
49
SPL(dB(A)) LINE
Hi
NOTCH
HEATING
Heating : DB 7: WB 6:
MUH-C07SV -
MUH-C09SV -
E1
E1
MUH-C18SV -
E1
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
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
Test conditions, Cooling : DB 35: WB 24:
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
COOLING
FUNCTION
47
SPL(dB(A)) LINE
Hi
NOTCH
HEATING
Heating : DB 7: WB 6:
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
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
Test conditions, Cooling : DB 35: WB 24:
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
COOLING
FUNCTION
45
SPL(dB(A)) LINE
Hi
NOTCH
HEATING
Heating : DB 7: WB 6:
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