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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.
T-Ratings
: Phones rated T3 or T4 meet FCC
requirements and are likely to generate less
interference to hearing devices than phones that are
not labeled. T4 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
is synonymous for T ratings. 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 is 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 Industries
Solutions (ATIS). The U and UT marks are referenced
in Section 20.19 of the FCC Rules.
The HAC rating and measurement procedure are
described in the American National Standards
Institute (ANSI) C63.19 standard.
Other Medical Devices
If you use any other personal medical devices, consult
the manufacturer of your device to determine if it is
adequately shielded from external RF energy. Your
physician may be able to assist you in obtaining this
information. Switch your phone off in health care
facilities when any regulations posted in these areas
instruct you to do so. Hospitals or health care facilities
may be using equipment that could be sensitive to
external RF energy.
Vehicles
RF signals may affect improperly installed or
inadequately shielded electronic systems in motor
vehicles. Check with the manufacturer or its
M3 + M2 = 5
T3 + T2 = 5
Virgin M340.book Page 81 Tuesday, April 14, 2009 4:14 PM