Samsung SPH-M300ISASPR - Manual (Page 252)

228 Section 4A: Important Safety Information
Using Your Phone With a Hearing Aid
Device
Your Sprint Nextel phone has been tested for hearing aid device
compatibility. When some wireless phones are used near some hearing
devices (hearing aids and cochlear implants), users may detect a buzzing,
humming, or whining noise. Some hearing devices are more immune than
others to this interference noise and phones also vary in the amount of
interference they generate.
The wireless telephone industry has developed ratings for some of their
mobile phones, to assist hearing device users in finding phones that may
be compatible with their hearing devices. Not all phones have been rated.
Phones that have been rated have a label located on the box.
Your Sprint Vision M300 phone by Samsung has an M4 rating and a T4
rating.
These ratings are not guarantees. Results will vary depending on the level
of immunity of your hearing device and degree of your 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 it for your personal needs.
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
be more usable with a hearing device's telecoil ("T Switch" or "Telephone
Switch") than unrated phones. T4 is the better/higher of the two ratings.
(Note that not all hearing devices have telecoils in them.)
The more immune your hearing aid device is, the less likely you are to
experience interference noise from your wireless phone. Hearing aid
devices should have ratings similar to phones. Ask your hearing healthcare
professional for the rating of your hearing aid. Add the rating of your
hearing aid and your phone to determine probable usability:
ⅷ Any combined rating equal to or greater than six offers best use.
ⅷ Any combined rating equal to five is considered normal use.
ⅷ Any combined rating equal to four is considered usable.