Hearing aids have not in the past always worked well with mobile phones, because of electronic interference between the two devices that caused static, whistling or screeching noises, or lost words. Fortunately, advances in technology and new government regulations have made the question “Will this phone work with my hearing aid?” easier to answer.
Government regulations introduce mandatory labeling requirements making it much easier to find a mobile phone compatible with your existing hearing aid.
The first thing you need to understand is that hearing aids operate in two different modes – microphone or “M” mode, and telecoil or “T” mode. Hearing aids in M mode are amplifying sounds coming through the phone. When the hearing aid is in T mode, instead of the microphone it uses its built-in telecoil to directly pick up conversations from inside the phone, in the form of electromagnetic signals. Currently, approximately 60% of hearing aids sold in the U.S. have a telecoil or T mode.
The rating system for these two modes of hearing aid operation uses a scale that ranges from the lowest sensitivity (1) to the highest sensitivity (4).To be sold in the United States as hearing aid compatible (HAC), a mobile phone or cordless handset must have a rating of at least M3 or T3.
Hearing aids and cochlear implants have a similar M and T rating system to certify how sensitive they are in each mode, and how resistant they are to radio frequency interference. When shopping for a phone, to determine its compatibility with your hearing aid, simply add its M and T ratings together with those of the phone to create a combined rating. If you get a combined total of 6 or more, that is thought of as excellent, a combination of hearing aid and phone that will be highly usable. A combined rating of 5 is thought of as normal, and suitable for most people. A combined rating of 4 is fine for short, infrequent calls, but probably not a good choice if you are a moderate to heavy phone user.
If you are shopping for a mobile phone online, you can usually use this combined rating to determine how compatible the phone you are interested in buying will be with your hearing aid. However, visiting a local store where you can try the mobile phone with your specific hearing aid is usually your best option. Use what you’ve learned in this article to narrow the phone choices based on the combined ratings and then actually make a phone call to test the two together.