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Safety information
M-Ratings
: Wireless mobile devices rated M3 or M4
meet FCC requirements and are likely to generate less
interference to hearing devices than mobile devices
that are not labeled. M4 is the better/higher of the two
ratings. M-ratings refer to enabling acoustic coupling
with hearing aids that do not operate in telecoil mode.
T-Ratings
: Mobile devices rated T3 or T4 meet
FCC requirements and are likely to generate less
interference to hearing devices than mobile devices
that are not labeled. T4 is the better/higher of the two
ratings. T-ratings refer to enabling inductive coupling
with hearing aids operating in telecoil mode.
Hearing devices may also be rated. Your hearing aid
manufacturer or hearing health professional may
help you find this rating. Higher ratings mean that the
hearing device is relatively immune to interference
noise.
Under the current industry standard, American National
Standards Institute (ANSI) C63.19, the hearing aid and
wireless mobile device rating values are added together
to indicate how usable they are together. For example,
if a hearing aid meets the M2 level rating and the
wireless mobile device meets the M3 level rating, the
sum of the two values equals M5.
