Health and Safety Information 191
The wireless telephone industry has developed a rating
system for wireless mobile devices to assist hearing device
users find mobile devices that may be compatible with their
hearing devices. Not all mobile devices have been rated.
Mobile devices that are rated have the rating on their box or
a label located on the box.
The ratings are not guarantees. Results will vary depending
on the user's hearing device and hearing loss. If your hearing
device happens to be vulnerable to interference, you may not
be able to use a rated mobile device successfully. Trying out
the mobile device with your hearing device is the best way to
evaluate it for your personal needs.
M-Ratings
: Mobile devices rated M3 or M4 meet FCC
requirements and are likely to generate less interference to
hearing devices than mobile devices that are not labeled. M4
is the better/higher of the two ratings.
T-Ratings
: Mobile devices rated T3 or T4 meet FCC
requirements and are likely to generate less interference to
hearing devices than mobile devices 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 mobile device 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.
If a hearing aid meets the M2 level rating and the wireless
mobile device 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
mobile device.
“Normal usage” in this context is defined as a signal quality
that is acceptable for normal operation. The M mark is
intended to be synonymous with the U mark. The T mark is
intended to be synonymous with the UT mark. The M and T
M3 + M2 = 5
T3 + T2 = 5