LG CU400 - Manual (Page 105)

101
Safety Guidelines
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 be more
usable with a hearing device’s telecoil
(“T Switch” or “Telephone Switch”) than
unrated phones. T4 is the better/higher of
the two ratings. (Note that not all hearing
devices have telecoils in them.)
Hearing devices may also be measured for immunity to
this type of interference. Your hearing device
manufacturer or hearing health professional may help
you find results for your hearing device. The more
immune your hearing aid is, the less likely you are to
experience interference noise from mobile phones.
To ensure that the Hearing Aid Compatibility rating for
your phone is maintained, secondary transmitters such
as Bluetooth and WLAN components must be disabled
during a call. See Page 74 for instructions to disable
these components.