immune than others to this
interference noise, and phones also
vary in the amount of interference
they generate.
The wireless telephone industry
has developed a rating system for
wireless phones, to assist hearing
device users to find phones that
may be compatible with their
hearing devices. Not all phones
have been rated. Phones that are
rated have the rating on their box or
a label located on the box.
The ratings are not guarantees.
Results will vary depending on the
user's hearing device and hearing
loss. If your hearing device
happens to be vulnerable to
interference, you may not be able to
use a rated phone successfully.
Trying out the phone with your
hearing device is the best way to
evaluate it for your personal needs.
M-Ratings: Phones rated M3 or M4
meet FCC requirements and are
likely to generate less interference
to hearing devices than phones that
are not labeled. M4 is the
better/higher of the two ratings.
Hearing devices may also be rated.
Your hearing device manufacturer
or hearing health professional may
help you find this rating. Higher
ratings mean that the hearing
device is relatively immune to
interference noise. The hearing aid
and wireless phone rating values
are then added together. A sum of 5
is considered acceptable for
normal use. A sum of 6 is
considered for best use.
In the above example, if a hearing
aid meets the M2 level rating and
the wireless phone meets the M3
level rating, the sum of the two
values equal M5. This should
provide the hearing aid user with
"normal usage" while using their
hearing aid with the particular
wireless phone. "Normal usage" in
this context is defined as a signal
quality that's acceptable for normal
operation.
The M mark is intended to be
synonymous with the U mark. The T
mark is intended to be synonymous
with the UT mark. The M and T
marks are recommended by the
Alliance for Telecommunications
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