Technical specification ANSI C63.19 has been developed to provide a way to measure the interference experienced by hearing aid users when using hearing aids with wireless handsets. The interference may be a buzzing, humming, or a whining noise .The amount of interference experienced by hearing aid users may vary based on the level of immunity of their hearing aids.Wireless handsets are tested to C63.19 and rated M1 to M4 with respect to RF interference between the hearing aid and handset. A wireless handset with a rating of M3 or M4 usually provides reduced RF interference for hearing aids designed for compatibility.
C63.19 also provides a rating to measure a wireless handset’s compatibility to telecoil (T-coil) hearing aids. Handsets tested for telecoil compatibility are rated T1 through T4. Handsets that receive T3, T4 usually provide better performance for use with telecoil hearing aids designed for compatibility.
Although a hearing aid compatibility ratings system is not a guarantee, it is a useful tool for consumers to determine the most appropriate wireless handset to match with their hearing aid.
The following statement applies to each of the current Cat
® HAC models that are listed in the chart below.
This phone has been tested and rated for use with hearing aids for some of the wireless technologies that it uses. However, there may be some newer wireless technologies used in this phone that have not been tested yet for use with hearing aids. It is important to try the different features of this phone thoroughly and in different locations, using your hearing aid or cochlear implant, to determine if you hear any interfering noise. Consult your service provider or the manufacturer of this phone for information on hearing aid compatibility. If you have questions about return or exchange policies, consult your service provider or phone retailer.
Phone Model |
HAC Rating |
Cat® S62 Pro |
M3/T3 |
Cat® S52 |
M3/T3 |
Cat® S42 |
M3/T3 |
Cat® S61 |
M3/T3 |
Cat® S48c |
M3/T3 |
Cat® S60 |
M3/T4 |
Cat® S50c* |
M4/T3 |
Cat® S41 |
M3/T4 |
Cat® S40 |
M3/T3 |
Cat® S31 |
M3/T4 |
Cat® S30 |
M3/T4 |
Cat® S50* |
M4/T4 |
Cat® B100* |
M3/T3 |
Cat® B15 |
M3/T3 |
Cat® B15Q* |
M3/T3 |
Choose the right phone
How can I tell which cell phones will likely work the best with my hearing aids?
The FCC’s hearing aid compatibility requirements address hearing aids that operate in either of two modes – acoustic coupling (“M” rating) or inductive coupling (“T” rating). Hearing aids operating in acoustic coupling mode receive through a microphone and then amplify all sounds surrounding the user, including both desired sounds, such as a telephone’s audio signal, and unwanted ambient noise. Hearing aids operating in inductive coupling mode turn off the microphone to avoid amplifying unwanted ambient noise, instead using a telecoil to receive only audio signal-based magnetic fields generated by inductive coupling-capable telephones. The FCC’s “M” and “T” ratings indicate whether a handset can be expected to function well with a hearing aid and are generally marked clearly on the handset packaging. The “M” or “T” rating does not guarantee that the handset will function without distortion or noise, so Smithville recommends that you test the handset before purchasing.The rating scale ranges from 1 to 4. The four possibilities are: M1 or T1 (poor), M2 or T2 (fair), M3 or T3 (good) and M4 or T4 (excellent).
Only phones rated 3 or 4 are allowed to be sold as hearing aid compatible (HAC). Phones that would have only been rated 1 or 2 are deemed unacceptable.
“M” (acoustic coupling) 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).
Thus, 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. (M4 is better.) This does not guarantee that these phones will be interference-free with your specific hearing aids. However, the higher the rating, the less likely you will be to experience interference. Also, note that just because a cell phone is not rated does not mean it will cause interference–they may or may not–but unrated phones are much more likely to do so. (How much interference a cell phone causes depends to a large extent on the transmission technology used: i.e. CDMA, iDEN, TDMA or GSM with CDMA being the best and GSM the worst.)
“T” (inductive coupling) Rating
Since September 18, 2006, cell phone companies have been required to provide several cell phones that are rated as being hearing aid compatible when used in t-coil mode (T3 or T4).
Therefore, if you use your cell phone while wearing your hearing aids in t-coil (“T”) mode, look for a phone that is rated T3 or T4. (T4 is better.) Again, this will not guarantee that these phone will be interference-free when using your t-coils, but the higher the rating, the less likely it is that you will experience interference.
Note that phones rated as T3 or T4 must also be rated either M3 or M4. Therefore, phones rated as good for t-coils will also have been rated good when used with hearing aids in the microphone mode.