Important Information: Cell Phones - Sonova Phonak Lyric 3 User Manual

8. Important information: Cell phones

Some hearing aid users have reported a buzzing sound
in their hearing aids when they are using cell phones.
According to the ANSI 63.19 (American National
Standard Methods of Measurement of Compatibility
Between Wireless Communications Devices and
Hearing Instruments) standard, the compatibility of a
particular hearing aid and cell phone can be predicted
by adding the rating for the hearing aid immunity to
the rating for the cell phone emissions. The sum of the
hearing aid rating (e.g. M2/T2=2) and the telephone
rating (e.g. M3/T3=3) is 5, and any combination that
equals 5 will provide "normal use"; a sum of 6 or
greater would indicate "excellent performance". The
equipment performance measurements, categories and
system classifications are based upon the best
information available but cannot guarantee that all
users will be satisfied. The immunity of this hearing aid
is at least M2/T2.
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