Ecotech Acoem Serinus 10 - Set-Up; Figure 101 - Typical Uses of Transfer Standards to Calibrate Instruments

Serinus® 10 User Manual 3.2
Page 122
 Ozone Transfer Standard Level 3 and greater – At beginning and end of Ozone season or every 6
months whichever is less.
Ecotech is able to offer a Level 2 and lower Ozone calibration service.
Note: Transfer standards must meet the requirements and specifications set forth by the user’s
local regulatory authority.
5.2.2 Set-Up
There are two common configurations used for certifying a photometer.
A Level 4 Ozone generation device supplies known concentrations of O3 to both the instrument being
certified and a Level 3 transfer standard. The photometer being certified can be compared to the Level
3 certified photometer.
A Level 2 Ozone generator and photometer both supplies and measures the levels of O
3
which is delivered to the instrument being certified.
Figure 101 – Typical uses of Transfer Standards to Calibrate Instruments.
To ensure good calibration, ensure the following;
 The calibration photometer (designated as a transfer standard) must be dedicated exclusively to
use as a calibration standard. It should always be used with clean, filtered zero air and never used
for ambient air sampling.
 All connections between components in the calibration system downstream of the O
3
generator
should be of glass, Teflon® or other relatively inert materials.
 Tubing should be of sufficient diameter to insure a negligible pressure drop at the photometer
connection and other output ports
 The zero air must be free of contaminants which would cause a detectable response from the O
3
analyser and it should be free of NO, C
2
H
4
and other species which react with O
3
.
 One source of zero air should be used for both the Ozone generation and the reference
measurement. This will ensure that other measurement variables (water vapour, other interferent
etc.) are eliminated from the calibration.
 The system must have a vent designed to ensure atmospheric pressure is maintained in the
photometer and to prevent ambient air from entering the manifold.