LG 450 User Manual page 89

The HAC rating and measurement procedure are described in the American
National Standards Institute (ANSI) C63.19 standard.
To enter 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
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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