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.
11. Important information: Cell phones
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