PROGRAMMING OF VRAE
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4.4 Calibration of VRAE Monitor
CALIBRATION WARNINGS:
The calibration of all newly purchased RAE Systems
instruments should be tested by exposing the sensor(s)
to known concentration calibration gas before the
instrument is put into service the first time.
For maximum safety, the accuracy of the VRAE should
be checked by exposing the sensor(s) to known
concentration calibration gas before each day’s use.
In programming mode, the user may re-calibrate the sensors
in the VRAE monitor. This is a two -point calibration
process using “fresh air“ and the standard reference gas (also
known as Span Gas). First, a “fresh air” which contains
20.9% and no detectable, toxic or combustible gases is used
to set the zero point for each sensor. Then a standard
reference gas, which contains a known concentration of a
given gas, is used to set the second point of reference. The
two-point calibration procedure is detailed below. Table 4.3
shows the sub-menus for calibration operations.
Table 4.3
Calibration Sub-Menu
Fresh Air Calibration?
VOL% Zero Calibration?
Multiple Sensor Calibration?
Single Sensor Calibration?
Modify Span Gas Value?
Change LEL/VOL Span Gas?
