phone meets the M3 level rating, the sum
of the two values equal M5. 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'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.
To ensure that the Hearing Aid
Compatibility rating for your phone is
maintained, secondary transmitters
such as Bluetooth components must be
disabled during a call.
For information about hearing aids and
digital wireless phones
Wireless Phones and Hearing Aid
Accessibility
84
http://www.accesswireless.org/
Gallaudet University, RERC
http://tap.gallaudet.edu/Voice/
FCC Hearing Aid Compatibility and Volume
Control
http://www.fcc.gov/cgb/dro/hearing.html
The Hearing Aid Compatibility FCC Order
http://hraunfoss.fcc.gov/edocs_public/
attachmatch/FCC-03-168A1.pdf
Hearing Loss Association of America
[HLAA]
http://hearingloss.org/content/
telephones-and-mobile-devices