4
interference will not occur in a particular installation. If this
device does cause harmful interference, which can be
determined by turning the device off and on, the user is
encouraged to try to correct the interference by one or
more of the following measures:
• Reorient or relocate the receiving antenna.
• Increase the separation distance between the two
interfering devices.
• Consult 3M Technical Services.
This product contains electrical and electronic
components and must not be disposed of using standard
refuse collection. Please consult local directives for
disposal of electrical and electronic equipment.
CAN ICES-3 (B)/NMB-3(B)
4. LABORATORY ATTENUATION
The attenuation rating (SNR/NRR) was obtained with the
device powered off.
4.1. EXPLANATION OF ATTENUATION
TABLES
4.1.1. EUROPEAN STANDARD EN 352
3M strongly recommends personal fit testing of hearing
protectors. Research suggests that users may receive
less noise reduction than indicated by the attenuation
label value(s) on the packaging due to variation in fit,
fitting skill, and motivation of the user. Refer to applicable
regulations or guidance on how to adjust attenuation
label values. In the absence of applicable regulations, it
is recommended that the attenuation rating be reduced to
better estimate typical protection.
EN 352-1 and EN 352-3
Table
ref.
Description
A:A
Headband with foam cushion
A:B
Headband with foam cushion
A:C
Carrier attachment with foam cushion
earmuff
A:D
Carrier attachment with foam cushion
earmuff
A:1
f = Octave-band centre frequency (Hz)
A:2
MV = Mean value (dB)
Table
ref.
Description
A:3
SD = Standard Deviation (dB)
A:4
APV* = MV - SD. (dB)
*Assumed protection value
A:5
H = Hearing protection estimation for high
frequency sounds (ƒ ≥ 2000 Hz).
M = Hearing protection estimation for
medium frequency sounds (50 0Hz <
ƒ < 2000 Hz).
L = Hearing protection estimation for low
frequency sounds (ƒ ≤ 500 Hz).
SNR = Single Number Rating of hearing
protection performance
A:6
S = Small
M = Medium
L = Large
EN 352-4
Table
ref.
Description
D:A
Criterion levels
D:1
D:2
D:3
D:4
H = Criterion level for high-frequency
noise
M = Criterion level for medium-frequency
noise
L = Criterion level for low-frequency noise
EN 352-6
Table
ref.
Description
E:A
External electrical safety related audio
input
E:1
Input signal level U (mV, RMS)
E:2
Sound output level (dB(A))
E:3
Criterion input signal (mV) for which the
sound output level is equal to 82 dB(A)
E:4
Sound output level for maximum input
signal (dB(A))
E:5
Time equivalent to 82 dB(A) over 8h
EN
