User's Manual

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device and hearing loss. If your hearing device
happens to be vulnerable to interference, you may
not be able to use a rated phone successfully. Trying
out the phone with your hearing device is the best
way to evaluate this.
M-Ratings: Phones rated M3 or M4 meet FCC
requirements and are likely to generate less
interference to hearing devices than phones that are
not labeled. M4 is the better/higher of the two ratings.
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 example illustrated above, 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 should provide the hearing-aid user
with “normal usage” while using their hearing aid with