Missouri Humidity and Hearing Aids – Part 1

Missouri Humidity and Hearing Aids (Part 1)
     By Heather Meyer

We have already talked a little about how rain or dampness can affect the performance of hearing aids, but what about other sources of moisture? And why might a hearing aid have problems with moisture in the middle of February as well as in the middle of August?

First a little lesson on the climate of Missouri.

Located in the continental interior, Missouri often experiences extremes in temperatures. Without high mountains or oceans nearby to moderate temperature, our climate is seasonally affected by air from the cold Arctic and the hot and humid Gulf of Mexico.

Relative humidity measures the percentage of water in the air compared to how much water the air can hold and fluctuates throughout the day along with the air temperature. At the coolest time of day, humidity usually peaks because cooler air holds less water. When the temperature rises during the day, the humidity usually drops. The ten most humid cities in America have a humidity level that averages over 72.5% year round, with New Orleans at the top of the list (86%). In comparison, St Louis and St Charles average about 70%, but typically ranges from 40% (comfortable) to 95% (very humid) over the course of the year.

Why should we care about the climate of our state? What does that have to do with hearing?

Well, if you wear hearing aids, you should pay more attention to what that climate is doing to affect their performance and overall longevity.

What humidity does to Hearing Aids

Moisture and condensation can damage the electronics in your hearing aid. Much of this damage is caused by the changes in temperature, which causes a condensation of moisture within the aid. This change can occur many times a day, as someone goes in and out of heated or air-conditioned environments. High humidity and perspiration exacerbate this problem. Battery corrosion is another symptom of humidity, and can also lead to poor aid performance, so frequent checks of the hearing aid battery is advised.

Moisture can destroy the microphone and the receiver of a hearing aid, clog the sound opening or earmold tubing, and cause corrosion. Anything wet, high humidity, perspiration, condensation, accidental immersion in a bath or pool, etc. can cause damage to a hearing aid and prevent it from functioning properly.

Symptoms of a Moisture Problem

·         Intermittent stopping and starting

·         Loss of clarity or distortion, sometimes static sound in the background

·         Cutting in/out on loud noises

·         Sound fading throughout the day

·         Frequent battery consumption

o   Check that the batteries are not the cause. Batteries recover some charge when rested. They may go flat and then work again for a short while after a rest. Buzzing and distortion are commonly experienced just before the battery goes completely flat. To eliminate batteries as a cause of the problem, replace the battery as soon as the aid stops and keep the new and used batteries separated.


Sources: Liz Osborn @ Current Results Nexus; and Phonak Hearing