;
,
,
),
3M.
FCC
EN 352
A :1
( )
A :2
, Mean att (dB)
A :3
A :4
A:5 H =
M =
L =
ANSI S3.19-1974
B :1
( )
B:2
, Mean Att (dB)
B :3
,
1.
,
2. NRR 23
(dB).
3.
:
C-
/
C :1
C :2
C :3
C :4
EN352-3:2003:
D. AS/NZS 1270:2002:
.
D :1
D :2
D :3
D :4
: S =
HRXS220A, HRXS221A, HRXS221A-NA
E : 1
(
E : 2
(
;
:
,
:
:
, St dev (dB)
, APV (dB)
, St Dev (dB)
,
A-
, 92 dBA.
,
.
AS/NZS 1270:2002
, Mean Att
, St Dev
,
,
, M =
, L =
, PVC, PA)
)
133
.
,
(
.
.
(ƒ 2000
).
(500
< ƒ < 2000
).
(ƒ 500Hz).
69 dB(A).
500
,
:
,
, 3M
,
.
,
NRR.
,
,