- “M” (Microphone) Rating
Since September 2005, cell phone companies have been required to provide several models of cell phones that are rated as being hearing aid compatible when used with hearing aids in the standard microphone setting (M3 or M4). If you use your cell phone while wearing your hearing aids in the microphone (“M”) mode, look for one that is rated M3 or M4. The higher the rating, the less likely you will experience interference.
- “T” Telecoil Rating
Since September 18, 2006, cell phone companies have been required to provide several cell phone that are rated as being hearing aid compatible when used in t-coil mode (t3 or T4). If you use your cell phone while wearing you hearing aids in t-coil (“T”) mode, look for a phone that is rated T3 or T4. Again, this will not guarantee that these phones will be intereference-free when using your t-coils, but the higher the rating, the less likely you will experience interference.