Enter the threshold levels for 500Hz, 1000Hz, 2000Hz, and 4000Hz, into the calculator to determine the pure tone average.
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Pure Tone Average Formula
The following formula is used to calculate a pure tone average.
PTA = SUM(TL) / 4
- Where PTA is is the pure tone average
- SUM(TL) is the sum of the threshold levels at the following sound frequencies:
- 500 Hz
- 1000 Hz
- 2000 Hz
- 4000 Hz
To calculate the pure tone average, add together the threshold levels at all of the hertz levels and divide by the number of levels (i.e 4 like the formula above).
What is a pure tone average?
A pure tone average is a measure of the average hearing sensitivity a person has at various frequencies.
These frequencies are typically measured at 3, 4, or 6 different frequency levels.
How to calculate pure tone average?
The following example problem outlines how to calculate a pure tone average:
First, determine the sensitivity at each of the 4 frequencies above:
In this example, these are as follows:
- 500 Hz = 5
- 1000 Hz = 6
- 2000 Hz = 7
- 4000 Hz = 8
Next, add up all the values: 5+6+7+8 = 26
Finally, divide the sum by 4 to get the pure tone average.
PTA = 26 / 4
PTA = 6.5