The vertical Y axis represents decibels. Decibels represent the hearing level, or how loud it is. The number of decibels are lower at the top of the chart, and get higher as you go downward. It is divided into three parts: The top part of the chart is the softer sounds, the middle part is the moderate sounds, and the bottom part is the louder sounds.
The audiologist tests your hearing at a range of frequencies. The audiologist is checking to see what the softest sound you can hear at each frequency is. For example, at 125 Hz you may be able to only hear the sound at 50 decibels.
A completed audiogram will have X's and O's on it. Each X stands for your left ear. Each O stands for your right ear. Look at the audiogram to see where the X's and O's line up with the decibel axis.
- Normal-hearing people will have X's and O's that don't go above 20 decibels.
- People with a mild hearing loss will have X's and O's in the 20 to 40 decibel range.
- A moderate loss is 40 to 60 decibels.
- Severe hearing loss falls in the 60 to 80 decibel range.
- A profound hearing loss is anything greater than 80 decibels.
Looking at my own audiogram (pictured), it is obvious that my own hearing loss is very profound, literally falling off the chart.
Source:
Understanding your hearing test. http://www.earinfo.com/how-to-read-a-hearing-aid-test/ Accessed September 2010
Hearing assessment. http://www.asha.org/public/hearing/testing/assess.htm Accessed September 2010

