User Guide

62
sonic · BLiss
Cell Phone and Hearing Instrument
Compatibility
Some hearing instrument users have reported
a buzzing sound in their devices when they are
using cell phones, indicating that the cell phone
and hearing instrument may not be compatible.
The compatibility of a particular hearing instrument
and cell phone can be predicted by adding the rating
for the hearing instrument immunity to the rating
for the cell phone emissions (ANSI C63.19-2006
American National Standard Methods of Measurement
of Compatibility between Wireless Communication
Devices and Hearing Aids).
For example, the sum of a hearing instrument with
a rating of 2 (M2/T2) and a telephone with a rating
of 3 (M3/T3) would result in a combined rating of
5. According to the standard, any combined rating
that equals at least 5 would provide “normal use”;
a combined rating of 6 or greater would indicate
“excellent performance.”