Thermo Scientific 49i, Instruction Manual, Page: 139 / 314

Calibration
Instrument Preparation
Thermo Fisher Scientific Model 49
i
Instruction Manual 4-3
Figure 4-1. Model 49 i Connected as Calibrator
Instrument
Preparation
Use the following procedure to prepare the instrument prior to calibration.
1. Turn on the instrument and allow it to stabilize for a minimum of one
hour. Perform the service checks in the “Preventive Maintenance”
chapter.
2. Connect the Model 49 i to the ozone manifold. If a Teflon® particulate
filter is being used, it must be installed prior to calibration.
Calibration
Photometer System
Preparation
As indicated in the EPA Technical Assistance Document there are several
tests that should be performed prior to the use of an ozone UV photometer
as a calibrator to ensure the accuracy of the measurements. These tests
include:
• System check
• Ozone loss test
• Linearity check
• Intercomparability test
System Check
A step-by-step checkout procedure to verify proper operation of a Model
49
i Primary Standard (or a Model 49 i modified as described earlier) is as
follows: