As of September 2005, the FCC requires wireless  Hearing Hero Review  phone manufacturers to provide carriers with some cell phones with reduced RF emissions for each of the transmission technologies. Those that are considered passing (rated "good" or "excellent") for use with hearing aids set in microphone mode will be assigned a HAC rating of M3 or M4. There are also "T" ratings for telecoil coupling. Look for a cell phone with a rating of T3 or T4 for aids coupled inductively (telecoil). M and T ratings range from 1 to 4. The higher the rating, the less likely the user will experience interference while using the cell phone.

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