But now a waterproof hearing aid has been developed and it is on the market in the US, Australia and in parts of Asia including Taiwan, Singapore, Korea, Hong Kong, Malaysia, Sri Lanka and Vietnam.
Trials for humidity tolerance have been carried out in Australia.
Presenter: Cameron Wilson
Speaker: Janette Thorburn, principal audiologist at the Australian government agency, Australian Hearing
THORBURN: Well the most significant thing is that for hearing aid wearers water's always been a major problem. Not just water as you think of a splash from the rain, but humidity, which gets right into the core of the hearing aid and hearing aids are a very sophisticated electronic piece of equipment trying to transmit very good quality sound, and so that humidity would get in there and disrupt that. So this is the big advantage and our trials found that these hearing aids are amazing at being robust and not being affected by that humidity that many of us who live in the northern parts of Australia are affected by. But also in humid countries; Japan did some trials and we did some trials and we just found that patients who had these hearing aids had no problems with them.
WILSON:When you say that the humidity disrupts the sound be transferred, what does it actually do?
THORBURN: Well it causes a couple of things, it can just cause hearing aids to fail completely. For example it gets into the battery compartment and causes corrosion, so then there's no power to the hearing aid and it fails, or it can affect the microphones and get into the delicate microphones and then really affect the sound quality of what you're getting.
WILSON: So people who live in humid countries, and particularly say parts of Asia, what would have been their options in the past?
THORBURN: They would just have had a lot of hearing aid repairs, they get very expensive, often some of the government systems pay for hearing aids, but that makes it expensive for governments and taxpayers. If you've actually bought your own hearing aids you don't want to be having to re-buy them regularly.
WILSON: Ok so one of the real problems was that hearing aids become something that only the rich people and rich countries can afford?
THORBURN: Yes absolutely.
WILSON: So what's so different about what you've come up with now, how does it actually work, if you can explain that in relatively simple terms?
THORBURN: Well these hearing aids are amazing in that they have an amazing coating, an amazing sealing systems, a seal like a bottle seal but it can keep the moisture out, and these seals and the way that the outside casing is beautifully coated protect it not just from water or humidity getting in, but also dust particles and because all of that is fairly soft it also protects it from shock. So you can imagine some very delicate acoustic equipment, if you put it down a bit hard on a table or drop it, that can affect it as well. So these have the advantage of protecting hearing aids from the humidity and water, but also shock and also dust, so it's great.
WILSON: Yes, of course, so if you're in a dry environment as well. It doesn't seem like such a radical idea to encase parts of the hearing aid inside a seal to protect it. Why has it been so difficult to come up with this breakthrough?
THORBURN: People have worked on it for years and indeed there's been some different versions of this and people have tried before, but this I think it's just taken all those previous versions to perfect it, to get the seals and the plastics and the way that they're making this so perfect that you just don't get the ingress from the humidity.
WILSON:: Does it need to be refined terribly much this technology?
THORBURN: No I think we've reached the point where this is good enough, this is great, because they've actually done testing to international standards, so for example they've used the international standard IP57 that looks at resistance to water and being able to cope with being submerged in water, and these hearing aids can sit in water for 30 minutes and not have any problems. So you could go for a swim and it'd be fine. So the level they've reached now is enough for general life.
WILSON: Are they terribly more expensive than a conventional hearing aid?
THORBURN: Overall not really, they are generally more middle to higher range, so yes they do perhaps cost a little more than the average, but for this effect that you're getting and the reliability that you're buying, it's excellent.
WILSON: So if you wouldn't have accounted for the costs of regular repairs or updates in a humid environment you may be better off?
THORBURN: Yes, yes, and particularly if you live in a humid environment.
WILSON: Do the hearing aid companies at all engage in preferential pricing to allow people in poorer countries or children to have access to these products?
THORBURN: Yes certainly the hearing aid companies look at the local market and very often there are programs that involve children or for example in Australia we're very lucky that the government provides hearing aids to our pensioner adult population as well as children. So generally the hearing aid manufacturers look at the local market and yes, you're absolutely right, there are generally some concessions to people who are on pensions, lower income and children.
WILSON: Does this work like other technology, is it expected that they will become cheaper and more easily accessible to more people the longer it's around?
THORBURN: Well I guess that is true of all technology, and yes, I'm sure that that will happen, but will take a little bit of time to filter down.
WILSON: What do they actually look like, is this a big and bulky device or is it quite a discrete device?
THORBURN: No that's the beauty of it actually, they've done a great job in designing the case, it looks very neat. They're no bigger than the normal size behind the ear hearing aid, and behind the ear hearing aids these days can be quite small. So they're very discrete, it's quite amazing that they've been able to keep all that, it's great.