I have seen the term "water-resistant" used for hearing aids and even for submergible cochlear implant processors. Are there any hearing aids that are waterproof?
That's a good question. After surveying hearing aid users across the United States, we found that there was a gap in the market for a truly waterproof, dustproof and shock-resistant instrument. We have successfully tackled all three concerns in the Aquaris™ product line, now commercially available.
The Aquaris housing is one solid piece with no seams and no screws or pins. The only entry points are the battery compartment, microphones, and the receiver area. We use the term bottle housing, in that we want to have the fewest number of openings in the housing as possible.
From a design standpoint, we incorporated a silicone seal that prevents any water from getting inside of the battery compartment. Keeping in mind that the battery needs air to breathe and function, there's a waterproof membrane that still enables the transfer of air in and out of the battery compartment to support the battery.
The microphones are also covered with a watertight membrane, as well as an extra cover on top of that to help deflect water and prevent any damage to the membrane. If we look at the receiver, there's a gasket around the base to prevent water from getting inside of the receiver opening. The receiver itself has a nanocoating on the grid, which prevents water from seeping in, working in conjunction with a thin tube or standard tube with earhook and earmold. Any custom earmold can be worn for daily use, but we recommend a non-vented, fully-occluding earmold for swimming.
To help prove and support what this housing is doing, we put it through an Ingress Protection rating test. Aquaris achieved a rating of IP57. The 5 in IP57 means that it is dustproof. The instrument is put into a dust chamber with fine powder blowing on it for eight hours, and it still has to function completely satisfactorily when it comes out of that chamber. The seven in IP57 means that the instrument can be completely submerged into three feet of water for thirty minutes and come out completely operational.
You can view more details about these tests and actually watch them being performed in a YouTube video, entitled Siemens Aquaris, tested tough. There are a number of videos on Aquaris, including the IP57 test, also on our Web site.
Eric Branda, Au.D. is the Senior Manager of Product Management at Siemens Hearing Instruments. He is responsible for the entire product life cycle, from development through phase-out.