SM010-3 Siemens SD 270 Operating & Service Manual Page 17
4 Sequence of Operation and Suggested Test Procedure
The following applies to air conduction measurements – refer also to ISO
8253 for further guidance.
4.1 Pre-test
(1) Switch the audiometer on
(2) Perform a listening check
(3) Decide whether to use the Threshold Retention Function, the Store on
2 of 3 option, or an audiogram card to record the thresholds
(4) Position the audiometer so that the patient cannot see the control
panel or any movement of the operator’s hands
(5) Fit the headset to the patient and use the TALKOVER
key to give the
following instructions to the patient:
“As soon as you hear the tone, press the response switch. When you
no longer hear the tone release the response switch”
(6) Select the better hearing ear (according to the patient) by pressing
either the LEFT or RIGHT key
4.2 Test
(7) Present the first test tone at 30dB at 1kHz
(8) If the patient responds, reduce the signal level in 10dB steps until they
no longer respond; then increase the signal level in 5dB steps until the
patient responds
(9) If the patient fails to hear the first tone, increase the signal level in 5dB
steps until they do respond and then continue with step 10
(10) Repeat the test by reducing the signal level in 10dB steps until the
patient no longer responds; then increase the signal level in 5dB steps
until they do respond and note this level
(11) If Store on 2 of 3 is selected, go to step 13
(12) Repeat step 10 until the patient responds three out of a maximum of
five times at the same signal level, indicating the patient’s hearing
threshold level for that frequency; mark the threshold on an audiogram
card or press the STORE key once to activate the Threshold
Retention Function which displays the threshold on screen
(13) If Store on 2 of 3 is selected, repeat step 10 until the patient has
responded 2 out of a maximum of 3 times at the same signal level;
this will automatically display the threshold on the screen
(14) Proceed to the next test frequency and repeat steps 7 to 13
(15) Repeat steps 7 to 14 for the other ear