Model 106-H Ozone Monitor Manual Rev. D-2
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5.
CALIBRATION
Every analytical instrument is subject to some drift and variation in response, making it
necessary to periodically check the calibration. Since the reliability of the data
collected from any analytical instrument depends on the accuracy of the calibration, it
is necessary to calibrate the instrument against a recognized standard such as the
International Ozone Association (IOA) KI method. This method is detailed in the
Iodometric Method for the Determination of Ozone in a Process Gas, Revised
Standardized Procedure 001/96 (KI Method) established by members of the Quality
Assurance committees of the International Ozone Association (IOA), including the Pan
American Group (PAG), European African Group (EAG) and Nippon Islands Group
(NIG). This procedure is an expanded version of the IOA method described in:
Rakness, K., et al., Guideline for Measurement of Ozone Concentration in the Process
Gas from an Ozone Generator,
Ozone Science and Engineering
18
, 209-229 (1996).
It should be noted that there is no method directly traceable to NIST for ozone
concentrations above 1 ppm.
5.1
Equipment Required
For routine calibration, an instrument can be calibrated against a working ozone
standard, which is an ozone monitor that has been calibrated against the IOA KI
method. The equipment that is needed to carry out the calibration is commercially
available. Calibration using a working ozone standard involves the generation of
ozone concentrations that are simultaneously measured by the working standard and
the instrument undergoing calibration. This procedure requires the following
equipment:
1. Zero gas source
2. Ozone generator
3. Sampling manifold (inert material such as PTFE or FEP only)
4. Sampling lines (inert materials such as PTFE or FEP only)
5. Ozone monitor calibrated against the IOA KI Method
5.2
Calibration Procedure
A multipoint calibration should be performed within the calibration frequency, any time
major disassembly of components is performed, or any time the span checks give
results outside of the acceptable limits.
5.2.1
Instrument Preparation
1. Turn on the Model 106-H Ozone Monitor and allow it to stabilize for a
minimum of one hour.
2. Allow the working standard to warm up according to the instrument user
manual.
3. Enter the calibration menu (Main Menu / Admin / Cfg / Cal / O3) and set
the zero (Z) value to 0.00 and the slope (S) value to 1.000.
4. Connect the ozone monitor to the manifold of the ozone calibration setup.
