User Manual

30
If your hearing device happens to be vulnerable
to interference, you may not be able to use a
rated mobile device successfully. Trying out the
mobile device with your hearing device is the
best way to evaluate it for your personal needs.
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 nd 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.