Welch Allyn TM286, Directions For Use Manual

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62 Standards, Specifications, and Accessories Welch Allyn TM286 Auto Tymp
Pneumatic System
Acoustic Reflex Stimuli
Output Levels
Pressure Range: +200 to -400 daPa
Notes:
1. 1 daPa = 1.02 mm H
2
0
2. The pressure sweeps to at least -100 daPa. To save test time, pressure
sweep stops when tympanogram returns to baseline after -100 daPa.
3. Full pressure sweep for 5 cm
3
from sea level to 7000 ft. altitude with no
leak.
Pressure Accuracy: ±10 daPa or ±15%, whichever is greater
Rate of Sweep: 600 daPa/sec except near tympanogram peak where sweep rate slows to
200 daPa/sec to provide better definition of peak compliance.
Direction of Sweep Positive to negative
Tympanogram Test Time: Approximately 1 second
Note
High compliance tympanograms will take somewhat longer.
Gradient: Measurement of the tympanogram width taken at 50% of peak
compliance.
Frequencies: 500, 1000, 2000, and 4000 Hz for ipsilateral stimulation
Accuracy: ±3%
Total Harmonic Distortion: <5% for outputs less than 110 dB HL and <10% at 110 dB HL
Rise/Fall Time: 5 to 10 msec
Transducers
IPSILATERAL: Probe Assembly
IPSILATERAL: 500 and 4000 Hz: 80, 90,100 dB HL
1000 and 2000 Hz: 85, 95, 105 dB HL
NOTES:
1. Ipsilateral stimuli are time multiplexed with probe tone (93 ms ON, 66 ms
OFF).
2. Stimuli are presented at lowest level first. If there is no response, the
intensity is increased by 10 dB until a response is detected or the maximum
dB HL is reached.
Pressure: Reflex measures are set automatically to pressure at peak compliance with
an offset of -20 daPa if peak pressure is negative and +20 daPa if peak
pressure is positive.
Reflex Determination: Compliance change of 0.05 cm
3
or greater.
Reflex Test Time: 1 to 12 seconds depending upon the number of ipsilateral
test frequencies selected (4 maximum) and intensity required.