Indoor Service Manual
11
10
OCH669A
NOISE CRITERION CURVES
UNIT
4 ft
MICROPHONE
CEILING
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
High
Medium
31
SPL(dB)
28
LINE
<60Hz>
NOTCH
Low
25
SLZ-KF09NA.TH
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
High
Medium
39
SPL(dB)
34
LINE
<60Hz>
NOTCH
Low
27
SLZ-KF15NA.TH
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
High
Medium
34
SPL(dB)
30
LINE
<60Hz>
NOTCH
Low
25
SLZ-KF12NA.TH
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
High
Medium
43
SPL(dB)
40
LINE
<60Hz>
NOTCH
Low
32
SLZ-KF18NA.TH
NOTE: The sound level is measured in an anechoic room where
echoes are few, when compressor stops. The sound
may be bigger than the indicated level in actual use due
to surrounding echoes. The sound level can be higher
by about 2 dB than the indicated level during cooling
and heating operation.