41
90
80
70
60
50
40
30
20
10
63
125
250
500
1000
2000
4000
8000
APPROXIMATE
TERESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCT
A
VE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
PKH-P4FALH
PKH-P4FALH
1
PKH-P4FALH
2
PKA-P4FAL
PKA-P4FAL
1
PKA-P4FAL
2
Hi
NOTCH
Lo
46
SPL(dB)
41
LINE
90
80
70
60
50
40
30
20
10
63
125
250
500
1000
2000
4000
8000
APPROXIMATE
TERESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCT
A
VE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
PKH-P2.5/3FALH
PKH-P2.5/3FALH
1
PKH-P2.5/3FALH
2
PKA-P2.5/3FAL
PKA-P2.5/3FAL
1
PKA-P2.5/3FAL
2
Hi
Lo
45
SPL(dB)
39
LINE
NOTCH
6. NOISE CRITERION CURVES
UNIT
WALL
1m
1m
MICROPHONE
Ambient temperature 27
:
Test conditions are based on JIS Z8731
OC175B--2.qxp 01.10.2 3:12 PM Page 41
