Real-Ear Measurements 115
5.2.4 Placing the Probe Tube
To ensure the proper insertion depth of the probe tube into the ear canal, the
following marking procedure is necessary. After some practice, the procedure is
easy.
1. Place an unattached probe tube on a flat surface along with the client’s
earmold or shell as shown in Figure 5.2.4A so that the tube rests along the
bottom of the canal part of the earmold, with the tube extending at least 5
mm past the canal opening.
2. Mark the probe tube with a marking pen where it meets the outside surface
of the earmold.
3. Place the wedge-style earhook on the client’s ear.
4. Attach the reference microphone, facing forward, on the wedge of the
earhook, directly above the ear to be tested.
5. Attach the probe tube to the body of the probe microphone and then attach
the Probe Microphone to the round Velcro pad on the ear hanger.
6. Insert the probe tube into the client’s ear so that the mark is at the location
where the bottom of the outer surface of the earmold would be. See Figure
5.2B.
Hints: To help keep the probe tube in place, position the tube so that it runs
through the tragal notch, resting against the lower edge of the tragus (Figure
5.2.4B) If necessary, reposition the body of the probe microphone lower on the
Velcro button of the ear hanger. If desired, use surgical tape to hold the tube in
position.
Reference
microphone
Wedge-style
earhook
Probe
microphone
Probe
tube
Figure 5.2.4A Figure 5.2.4B Figure 5.2.4C
Mark the probe tube. Place the microphones Insert the hearing aid.
