For your safety
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 and WLAN components must
be disabled during a call.
When you're talking on a cell phone, it's recommended that you turn the BT
(Bluetooth) or WLAN mode off for HAC.
For information about hearing aids and digital wireless phones
Wireless Phones and Hearing Aid Accessibility
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
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