CareFusion MicroCO Meter Betriebshandbuch Seite 20

The unit must not be used, however, for one second after the unit is
first switched on i.e. before the countdown commences. Exp ired
alveolar gas is then entrapped between sensor and mouthpiece valve.
The display reading will rise to a plateau over the course of a several
seconds. The final value will be held until the unit is turned off and
represents parts per million C O or %C OHb depending on the slide
switch position.
The lights will come on according to the table on page 12 and the red
light will flash and an alarm will sound if the measurement rises above
72ppm (12%C OHb).
If this occurs then the possibility of C O poisoning should be
investigated as this level of C O is unlikely to be produced by cigarette
smoking.
Important note:
Before repeating a measurement the unit must be turned off,
and the mouthpiece and adapter removed for at least 1 minute.
This is to allow re-equilibration with ambient air and to dry the
surface of the sensor. Visually inspect that all moisture has
evaporated from the surface of the sensor before reuse.
If the unit is switched on again too quickly after use there may be a
response to residual expired carbon monoxide from the previous test.
In this case the display will show:
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