Welch Allyn MicroTymp 3 portable tympanometric instrument - User Manual - Manual (Page 40)

40 Interpreting test results Welch Allyn MicroTymp3 portable tympanometric instrument
Influence of altitude
As the altitude above sea level increases, the admittance of a given volume of air also
increases. Therefore, equivalent ear canal volume (+200 Vea) overestimates actual ear
canal volume as noted in the table below. To estimate ear canal volume, subtract the
appropriate value in the table from the Vea Reading. Altitude can also affect MicroTest
Cavity results. See Functional Checks starting on
page 55 .
Influence of temperature
No corrections for temperature are required with this device.
Altitude adjustments for Vea readings
Altitude Adjustment
for 0.2 cc Adjustment
for 0.5 cc Adjustment
for 1.0 cc Adjustment
for 1.5 cc Adjustment
for 2.0 cc Adjustment
for 2.4 cc
-1200 ft (-366 m) 0.0 cc 0.0 cc 0.0 cc 0.0 cc 0.0 cc 0.0 cc
0 ft (0 m) 0.0 cc 0.0 cc 0.0 cc 0.0 cc 0.0 cc 0.0 cc
1000 ft (305 m) 0.0 cc 0.0 cc 0.0 cc 0.0 cc 0.0 cc 0.0 cc
2000 ft (610 m) 0.0 cc 0.0 cc 0.0 cc 0.0 cc 0.0 cc 0.1 cc
3000 ft (914 m) 0.0 cc 0.0 cc 0.1 cc 0.1 cc 0.1 cc 0.1 cc
4000 ft (1219 m) 0.0 cc 0.1 cc 0.1 cc 0.1 cc 0.1 cc 0.1 cc
5000 ft (1524 m) 0.0 cc 0.1 cc 0.1 cc 0.1 cc 0.1 cc *
6000 ft (1829 m) 0.1 cc 0.1 cc 0.1 cc 0.2 cc 0.2 cc *
7000 ft (2134 m) 0.1 cc 0.1 cc 0.1 cc 0.2 cc 0.2 cc *
8000 ft (2438 m) 0.1 cc 0.1 cc 0.2 cc 0.2 cc 0.3 cc *
9000 ft (2743 m) 0.1 cc 0.1 cc 0.2 cc 0.3 cc 0.3 cc *
10000 ft (3048 m) 0.1 cc 0.2 cc 0.2 cc 0.3 cc 0.4 cc *
* The MicroTymp3 will read “OPEN” when used on this ear canal volume at this altitude and will not run a test.