What is a Hearing Test
...and what does it indicate?
Hearing testing has not changed much since the 1940's - The only real difference is that our equipment has gotten more sensitive. Modern clinics use advanced equipment that enables testing up to 20,000 Hz instead of the standard 8,000 Hz.
When we test, we produce a graph but what does it really tell us?
It give us the "hearing loss" of the person.
The majority of damage to the ear (or "hearing loss") in most people are in the higher frequencies. But it is the low frequencies that determine how loud we hear things. Things like people walking up behind us, cars coming, calling our names. A sharp drop in hearing higher frequencies is often an indicator of noise-induced hearing loss.
So our ability to determine loudness or what we consider hearing is fine. Most people with a "hearing loss" "hear" as well as people without a hearing loss, which is why we hate the term "hearing loss"!
What is impaired is communication. You can hear most things; you just have to work harder. And really, who wants to work that hard all the time?
It’s tiring. And made more difficult in situations like noise or people who speak with an accent or a soft squeaky voice. Which means you tune out. Then it's a problem. In fact, fatigue is probably the most common symptom of a hearing problem.
An audiogram represents primarily how well the ear (as an organ) is functioning. 10% of hearing is done here. The other 90% is done between the ears (your brain). The images to the right shows what a standard audiogram looks like. (Thanks to the Tinnitus and Hearing Clinic for supplying these audiograms.)
Hearing level is in decibels. This is a logarithmic scale, like the Richter scale, rather than a linear scale. Frequency is reflected across the bottom, with 125 Hz indicating your ability to hear low pitched bass sounds, while 4,000 Hz indicates your hearing ability in high pitched treble sounds.
The X's represent the left ear and the O's the right. Before photocopiers, the right was always red and the left always blue. A normal graph would have all the X's and O's above 15 dB. (We have changed the bar. It used to be 20 dB and many people still use that level. But like golf, the lower the level, the better.)
This third audiogram shows the most common type of hearing loss. It is a high frequency loss that is caused by noise, medications (ototoxicity) or genetics.
Medications that cause hearing loss are also known as ototoxic medications. Here's a list of some of the common medications that cause hearing loss.. viagra included!
We are sad whenever hearing loss is caused by noise. See, noise-induced hearing loss is 100% preventable. You can take steps to protect yourself from noise exposure.
It is a myth that old age causes hearing loss - Living does!
1 in 4 kiwis suffer from noise-induced hearing loss (NIHL) Are headphones all to blame? Does age cause hearing loss?
It doesn't have to be difficult or costly. Learn the 3 basic steps to help you effectively control noise in your environment.
How can I protect my staff or myself at my workplace? What does the law say about noise exposure?