CHAPTER TWENTY-SEVEN
Technical specifications
204
Technical specifications
Our OAE probe contains a microphone which is used to both calibrate the stimulus
sound level and detect the otoacoustic emission. This ensures that the same
accuracy applies to both applied stimulus and the recorded OAE sound levels. All
our probes are factory tested and calibrated to be within these limits.
27.1.11
Environmental
Protect from heat and radioactive sources
Keep dry
Transport and storage:
Temperature range: 0 to 40 Celsius
Pressure:
23KPa to 101KPa
Humidity:
10% to 90% non-condensing
Warm-up time:
<10s when unit is stored within stated temperature
range
Operating:
Indoor use
Temperature range: 5 to 40 Celsius
Humidity:
Max 80% up to 31C decreasing linearly to
5% RH at 40C
Otodynamics instruments and probes are calibrated at an ambient pressure of 101
kPa (standard atmospheric pressure at sea level). Lowering the ambient pressure
significantly (e.g. when operating at altitude) alters the acoustic response of the
probe. For instance, at an ambient pressure of 80 kPa (standard atmospheric
pressure at 2000m) changes of up to 2 dB can be observed in the response of the
probe around 2KHz. This could cause the probe to fail standard calibration tests.