CareFusion Smoke Check Manuel D'utilisation page 49

Turn the unit on by pushing the central slide switch up and the three
colored lights will illuminate momentarily together with all the display
legends:
Ask the subject to inspire and hold their breath.
The unit will auto-zero for twelve seconds during which time the
following will be displayed:
Important note: the unit must not be used during this period.
After twelve seconds the display will change to:
Bat
7-10 ppm
Wait
Blow
0-6 ppm
Gas
Wait
Wait
0-6 ppm
20+ ppm
11-20 ppm
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