GSI 18
Determining the threshold (Pure Tone)
1. Present the first tone at 50 dB in the subjects better ear, or if no preference, the right ear.
Decrease the intensity in 10dB steps until the subject no longer responds. Increase the
intensity in 5dB steps until the patient responds.
NOTE: Down 10 dB, Up 5 dB.
2. The threshold is considered to be the lowest intensity at which a response has occurred
two out of three times. Record this setting on the audiogram form using the appropriate
symbol for L (X) or R (O).
Testing procedure
1. A suggested order in which to present frequencies is as follows:
1000 Hz, 500, 250 repeat 1000, 2000, 3000, 4000, 8000 Hz.
An alternative order is as follows:
250 Hz, 500, 1000, 1000 again, 2000, 3000, 4000, 8000 Hz.
2. The 1000 Hz retest is to verify the results of the test and to ensure the subject
understands the task.
If there is a difference of 20 dB or more between two successive octaves, test the inter-
octave responses (i.e., 750, 1500, 3000 Hz). Record this information on the audiogram
form.
3. Repeat for the other ear.
2-9 1718-0100 Rev. E
To Next Page
Loading...
Need help?
General
