Service manual

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
PU12EK
50
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
PU24EK PU30EK
PU24EK1 PU30EK1
PU24EK2 PU30EK2
PU24EK3 PU30EK3
55
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
PU18EK
PU18EK1
53
SPL(dB) LINE
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
PU36EK
PU36EK1
PU36EK2
PU36EK3
55
OC247-E--1.qxp 04.8.11 4:25 PM Page 7