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20. Important information:
Cellphones
Some hearing aid users have reported a buzzing sound
intheir hearing aids when they are using cell phones.
According to the ANSI 63.19 (American National
StandardMethods 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
therating for the hearing aid immunity to the rating for
the cell phone emissions. The sum of the hearing
aidrating (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
classications are based upon the best information
available but cannot guarantee that all users
will be satised. The immunity of this hearing aid is at
least M2/T2.