Q: I’ve heard a lot about waterproof hearing aids lately, is this important feature to look for? Are all waterproof hearing aids completely waterproof?
A: This question came from a client who swims a lot, particularly when she is down south in Florida. It’s an excellent question and one that I am happy to say has several answers. You see, up until a few years ago, hearing aids were highly allergic to water. Even more so if the water contained any salt, a compound that can damage so many otherwise sturdy materials. We all know the effects of road salt on the chassis of our cars, and it is significantly more potent to the components of a hearing aid. Sweat is one of the major causes of hearing aid malfunction, particularly for those who are very active.
There are several companies who manufacture both waterproof and water resistant hearing aids. Two of the most vocal are Phonak and Siemens; Phonak’s H2O series, and now the Q series, claim to be completely water PROOF. Siemens Aquarius line makes the same claim. Well the proof was in the pudding; we tested both by putting two functioning, battery laden hearing aids, one from each company, into a glass of water for three hours. The test would be, once they were taken out, would they work? The answer was yes, on both counts. Granted, we had to shake the excess water from the soundtubes (they act like capillaries, water can be taken up with very little force), but both performed perfectly after their mutual baths.
So where does this become important? And how is it that this is accomplished, when it has never been possible before? Well, you may have heard a recent buzz word, “nanotechnology”; essentially this means any product that has to be measured to no more than 100 nanometers, or billionths of a meter. That’s a “B”, so take a meter stick and cut it into a billion equal pieces, then use less than 100 of those pieces. It’s pretty small! Well, nanotechnology is currently in its infancy, but it’s uses are being studied for everything from rust proofing to yet smaller computer chips. In this case, the technology is being used to create a liquid impermeable, but gas permeable coating, which is glazed onto everything inside the hearing aid: microphone, receiver, battery contacts, amplifier, computer chip – everything. The very small atoms and molecules in the coating, which are generally spherical, have even more nanoscopic gaps between them, large enough to let gases through, (i.e. air, carbon dioxide), but too small to allow liquids like water permeate it. If water doesn’t get in, it’s conductive properties are not going to effect the performance of the electronics inside, rendering the hearing aid water proof.
Both of these companies have tested their products to 10 meters of depth in seawater, both passed and both are tremendously good products. Siemens promotes theirs with the assistance of a severely hard of hearing Olympic swimmer and professional dancer, Kristy Swain, who uses a peripheral device to transmit music from her iPod to her hearing aids while she’s swimming laps in the pool. Phonak used my employee, Andrea Sloan, who ran a marathon in Vermont, endured pouring rain and sweated buckets, none of which phased the H2O product.
Widex, who make the previously written about Zen product, also have a hearing aid which is less pervious to water, although they don’t claim it is water proof. Instead they call it water resistant, but have not performed depth tests to see what level the product is waterproof to. Instead they promote the removal of the hearing aids for bathing and swimming.