LG Optimus F7 User Manual page 90

Safety
90
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.
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 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.
When you're talking on a cell phone, it's recommended that you turn the BT
(Bluetooth) mode off for HAC.
According to HAC policy(KDB 285076), we state this handset has not been
rated for hearing aid compatibility with respect to the WiFi capability.
For information about hearing aids and digital wireless phones
FCC Hearing Aid Compatibility and Volume Control
http://www.fcc.gov/cgb/dro/hearing.html
Gallaudet University, RERC
http://tap.gallaudet.edu/Voice/
Hearing Loss Association of America [HLAA]
http://hearingloss.org/content/telephones-and-mobile-devices
The Hearing Aid Compatibility FCC Order
http://hraunfoss.fcc.gov/edocs_public/attachmatch/FCC-03-168A1.pdf
In the example to the left, 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