Thermo Scientific 49i, Instruction Manual, Page: 144 / 314

Calibration
Calibration Procedure
4-8 Model 49
i
Instruction Manual Thermo Fisher Scientific
1. Set ozone level thumb wheel to zero.
2. At the Teflon® distribution manifold, disconnect the line from the
ozonator to the manifold and cap fitting.
3. Cap bulkhead labeled VENT.
4. Connect Teflon® line from bulkhead labeled OZONE to manifold of
ozone source being utilized for intercomparability study.
5. Make sure the same zero air is feeding both the Model 49 i Primary
Standard and the second photometer being used in study.
6. If it is desired to hold usage of zero air to a minimum, adjust the
pressure regulator feeding the ozonator to zero pressure.
7. Perform intercomparability test.
8. After completion of test, reconnect ozonator and leak check following
the “Leak Test and Pump Checkout” procedure in the “Preventive
Maintenance” chapter.
Note If an ozone analyzer is available in addition to the two ozone
photometers being checked for intercomparability, an easier
intercomparability check is to calibrate the ozone analyzer against each
photometer individually and then compare the two ozone calibration
curves.
If a calibration photometer other than a Model 49 i Primary Standard or
modified Model 49 i is being used, follow the checkout procedure given in
the Manual for the calibration photometer, or follow the procedure in the
Technical Assistance Document.
Calibration Procedure
To generate data of the highest confidence, it is recommended that a
multipoint calibration be performed:
• every three months