User's Manual

116
SAFETY
aring 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. In the above example, 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 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 is
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.
For information about hearing aids and digital wireless
phone:
• FCC Hearing Aid Compatibility and Volume Control
http://www.fcc.gov/cgb/dro/hearing.html
• GallaudetUniversity,RERC
http://tap.gallaudet.edu/DigWireless.KS/DigWireless.htm
• Self Help for Hard of Hearing People Inc. [SHHH]
www.hearingloss.org/hat/TipsWirelessPhones.htm
• The Hearing Aid Compatibility FCC Order
http://hraunfoss.fcc.gov/edocs_public/attachmatch/ FCC-03-168A1.pdf