INFICON 2020ComboPRO Portable Photoionization Detector - Manual (Page 54)

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Figure 14. Interval Mode Display
GAS Mode
In GAS mode, the benzene pre-filter tube (Part No. F1760161) is used to measure
benzene. The GAS mode is a filter tube mode, so all benzene measurements require
the installation of the pre-filter tube holder (Part No. A1790500) and one of the
benzene pre-filter tubes. The benzene pre-filter tube, which is mounted at the head
of the tube holder, adsorbs all substances with the exception of benzene in order to
selectively measure benzene. The entire process is menu driven. The benzene
measurement value is displayed after 45 seconds.
Activating the GAS mode opens a dialog which calls for a device calibration. The
benzene measurement screen is displayed after installation of the benzene pre-filter
tube.
Figure 15. Gas Mode Display for Benzene Measurements
The following values are displayed: benzene concentration in ppm, STEL value, the
highest benzene measurement value recorded so far (SMAX), the amount of