6
AUDIO INPUT LEVELS
The audio levels in the earphones are dependent on the audio input level. To prevent
harmful noise levels in the earphones, never exceed the values and usage described
in Figure A:1. Mean/average level of electrical input. Maximum permitted audio input
level for 8 hours of usage time, compressed speech and music is
xxx
mV, see Figure
A:1, page
2
.
TEST RESULTS AND TECHNICAL DATA
TESTED ACCORDING ANSI , AS/NZ
*D1) Frequency, Hz, *D2) Mean Attenuation, dB, *D3) Standard Deviation, dB, *D4)
Mean-minus standard deviation, dB. *D5) Headband Force.
EXAMPLE:
1.
The environmental noise level at the ear is
xx
dB (A).
2.
The NRR is
xx
decibels (dB).
3.
The level of noise entering the ear is approximately equal to
xx
dB (A).
CAUTION:
For noise environments dominated by frequencies below 500 Hz, the
C-weighted environmental noise level should be used. Improper fit of this device will
reduce its effectiveness in attenuating noise. Although hearing protectors can be
recommended for protection against the harmful effects of impulse noise, the Noise
Reduction Rating (NRR) is based on the attenuation of continuous noise and may not be
an accurate indicator of the protection attainable against impulse noise, such as gunfire.
Constant or repetitive exposure to impulsive noise may lead to serious injury, including
temporary or permanent deafness. The Noise Reduction Rating (NRR) calculated from the
attenuation data is xx dB. Earmuffs must be properly fitted to attenuate noise effectively.
Refer to instructions.
NOTE:
The Noise Reduction Rating is derived from testing procedures at an independent
laboratory and in accordance to acceptable A.N.S.I. standards. Actual noise reduction
can vary from laboratory results as labelled. Protection is maximized when: proper
protector is selected for application, a good training program is utilized and proper
fitting techniques are followed.
ATTENUATION DATA
Verishield is tested and approved in accordance with ANSI S3.19-1974 Standard at
Michael & Associates Inc., USA. Verishield Attenuation Data according to American
National Standards Institute Specifications ANSI S3.19-1974 (in passive mode,
electronics switched off)
The level of noise entering a person’s ear, when hearing protection is worn as directed, is
closely approximated by the difference between the A-weighted environmental level and
the NRR.
ELECTRICAL INPUT / USAGE TIME - FIG. A:1
Maximum permitted audio input level for 8 hours of usage time, compressed speech
and music xxx mV.
Hours of usage/day
Heures d’utilisation par jour, Horas de uso/día *1)
