PROGRAMMING OF IAQRAE
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4.6 Change Sensor Configuration
The user may change several sensor related configurations.
The Change Sensor Configuration contains the following
configuration options:
Change VOC Measurement Gas?
Edit Correction Factor?
Enable/Disable Sensors?
Change Custom Gas Name?
Correction Factors
The PID sensor used in IAQRAE responds to a broad range of
gases. Typically, the PID sensor shows a different sensitivity to
different gases. To measure different gases, a correction factor
(CF) can be applied, defined as:
Sensitivity to a measurement gas
CF = __________________________________
Sensitivity to isobutylene calibration gas
When the monitor is calibrated to isobutylene, but used to
measure another compound, the CF is multiplied by the
reading to obtain the true concentration:
True Concentration = CF x PID reading
The IAQRAE has a library of 87 correction factors for the 10.6
eV PID sensor relative to isobutylene. The user may also use a
different gas than isobutylene to be the calibration gas.
For example, the user may choose benzene as the calibration
gas and chlorobenzene as the measurement gas. The IAQRAE
monitor will calculate a new correction factor between these
two compounds and convert the measured value into the
equivalent concentration of chlorobenzene.
