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4.6 AUDIOMETRY
NORMAL
A normal response from a child should be at or below 20 dB HL.
A normal response from an adult may be higher, at or below 25 dB HL.
These normal values assume a sufficiently quiet environment
during testing.
ABNORMAL
In children, a failure to respond to a 20 dB HL (or lower) stimulus pre-
sentation during a retest performed four to six weeks after the initial
test, would indicate the need for more extensive diagnostic testing to
determine the cause.
In adults, a failure to respond at or below 25 dB HL when the room
noise levels are low, indicates the need for more evaluation. How-
ever, the age and employment history of the individual must also be
considered.
4.7 SPECIAL MESSAGES AND ERROR CODES
Special messages and error code numbers may be displayed on the
screen or on the printout. Special messages appear to apprise the op-
erator of certain situations. For example, if there is no test result on the
screen and the PRINT SCREEN button is pressed, the printer will
indicate “No Test To Print”.
An error code appears as a two-digit number prefixed by the letter
“E”. If an error code appears, repeat the operation that caused the
error code to appear. If the error code appears for the second time,
contact Welch Allyn with the exact error code number.
4.8 SAMPLE TEST RESULTS
Range of Normals
Ear Canal Volume 0.2 - 2.0
Compliance Peak 0.2 - 1.4
Pressure Peak –150 - +100
Gradient 60 - 150 Child
50 - 110 Adult
Acoustic Reflex Yes or No
FIGURE 4-1: RANGE OF NORMALS
