Until only a few years ago there was little one could do about moisture-related problems in hearing instruments in a desiccant kit or add gain if the instrument was suspected of being damaged. However, a number of hearing instrument clearing devices in the last few years have been developed to help solve moisture problems, including the vacuum-generating device from Best Computes, MedRx and Starkey.

"Our information suggests that a hearing instrument can be dampened from 0-8 dB at 3000 Hz within 30 days of the fitting by moisture and debris," says Bill Burden, founder of Best Computes, manufacturer of the MarkV cleaning system for dispensers and the Sentinel drying system designed for everyday (at-home) patient use. "For many years, a number of dispensers have been using vacuums that they have 'jury-rigged' in order to remove debris (ear wax) from hearing instruments. Dispensing professionals also use canned air and tools to clean volume controls and other parts of the aid. However, the moisture problem cannot be effectively addressed this way."

The technology developed by Best Computes features a proprietary canister on the top of the device designed to "bleed" air over the hearing instruments while a vacuum exerts pressure. Alterative designs are offered on competitive units. A meter on the face of some of these instruments indicates the vacuum pressure-level, which Burden says can be helpful for ensuring that the vacuum is working unobstructed and drawing optimal pressure.

With the Mark V cleaning device designed for use in dispensing offices, the hearing instrument microphone, receiver and vents are vacuumed using the appliance's milled needle probe, then the instrument is place in the vacuum chamber which runs for five minutes, shutting off automatically. The probe-needle is then reinserted into the microphone and receiver to remove the remainder of the moisture and debris.

Burden believes that the marketing potential for these types of devices is large: "debris management is done extremely well by some hearing care professionals, and not at all by others. When the dispenser starts talking about making a client's existing equipment sound better, people who put their hearing instruments in the drawer start paying attention, and they generally are not adverse to coming into the office and paying a small fee to see if the cleaning system can enhance their hearing performance. Whether the professional bills for the service or not, it is a very important component for a dispensing office. However, if the service is billed for, like anything else, this gives it a validity and value.

"Moisture-related hearing instrument failures are not any-one's fault, and they occur regardless of climatic conditions. The problems are the product of tiny, complex devices living in a very electronics hostile environment, the human body.

"If we could start pulling the hearing instruments that are in drawers due to moisture problems and placing them back on people, as well as reducing repairs and increasing the service life of the instruments: I believe we could radically improve customer satisfaction.