Welch Allyn MicroTymp® 4 Tympanometer User Manual
DIR 80024157 Ver A
Page 29
Remove the probe and repeat the test with the three remaining test cavities. When tested at
elevations below 1,000 ft, the display should show the volume of the 0.2ml, & 0.5ml test cavities
to within ± 0.1ml. The volume of the 5.0ml test cavity should be shown within ± 0.25ml. When
the checks have been completed press
◄
to return to main menu.
TEST
CAVITY
READINGS
AT
ELEVATIONS
GREATER
THAN
1,000FT
ABOVE
SEA
LEVEL
The instrument is a pressure sensitive device that makes measurements relative to ambient air
pressure. Changes in air pressure due to weather or elevation will affect the ECV readout of the
instrument. Slight weather related barometric pressure changes will usually yield volume
readouts with ± 0.1 ml of the expected cavity value, but barometric pressure changes due to
elevation can be more significant. These changes in pressure do not affect the accuracy of the
compliance measurement system in any way. However, it will affect the ECV and Test Cavity
values.
If the MicroTymp 4 is being used at an elevation greater than 1,000 ft, when new, and after
each recalibration, perform a Daily Check on all 4 test cavity volumes (0.2ml, 0.5ml, 2ml & 5ml).
Record the displayed values for each cavity and use these values are “normal” when
performing Daily Checks each day thereafter.
Elevation (above sea level)
Resulting 2.0 ml reading
Feet
Meters
0
0
2.0 ±0.1
1000
304.8
2.1 ±0.1
2000
609.6
2.2 ±0.1
3000
914.4
2.2 ±0.1
4000
1219.2
2.3 ±0.1
5000
1524.0
2.4 ±0.1
6000
1828.8
2.5 ±0.1
7000
2133.6
2.6 ±0.1
