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T-Ratings
: Phones rated T3 or T4 meet
FCC requirements and are likely to
generate less interference to hearing
devices than phones that are not
labeled. T4 is the better/higher of the
two ratings.
Hearing devices may also be rated. Your
hearing device manufacturer or hearing
health professional may help you find
this rating. Higher ratings mean that the
hearing 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 is synonymous for T ratings.
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
M3 + M2 = 5
T3 + T2 = 5
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