NOy*/NOy
Audit and Calibration
Purpose: The NOy*/NOy audit and calibration is to assure that the NOy*/NOy analyzer has the correct
gas response. This can be accomplished
by introducing a known quantity of gas to the inlet and auditing the response
on the instrument. The terminology for
this type of audit is GRC (Gas Replacement Calibration). Each GRC has a RF (Response Factor). This RF value should be 1.000 +/- 2%.
Required Equipment: Precision flat head
screwdriver
Analyzer Setup
1. The
Background (BKG) and Coefficient (COEF) on the analyzer should be set to 0.0
and 1.000.
2.
On the “C” or “CTL”
model analyzers press “Menu” and scroll to “Calibration Factors” and press
“Enter”. At this point, the parameters
should be set as follows: Pre BKG PPB
=0.0, NO BKG PPB= 0.0, NOx BKG PPB =0.0, NO COEF =1.000, NOx COEF =1.000 &
NO2 COEF =1.000. Press Run when
finished.
Analyzer Audit
1. Open
the Gas Calibration Worksheet and enter the correct NO concentration (found on
the gas cylinder) in the blank
provided.
3.
In Site Manager screen go to the Tools tab and select Trigger Cals.
4.
In the Trigger Cals menu
select NOy Zero and press Start Calibration.
5.
Under the Tools tab
select Query 1-Minute Data.
6.
In the Query Data Tool
Menu select the Air MFC, Gas MFC, NOy* and NOy.
7.
Wait 13 minutes and
verify the Zeros for NOy* and NOy
are stable (+/-0.1 ppb). Contact
8.
Enter the Air MFC, NOy* and NOy data in the
appropriate blank for the NOy Zero on the Gas
Calibration Worksheet in the As Found section.
9.
Go to Trigger Cals and
press Stop Calibration then select NOy*/NOy NO GRC Point 1 and press Start Calibration.
10.
Wait 13 minutes and
verify the data for Noy* and NOy are stable (+/-
0.2ppb), then press Get Data.
11.
Enter the Air MFC, Gas
MFC, NOy* and NOy data in
the appropriate blanks for the NOy*/NOy NO GRC Point 1 on the Gas Calibration Worksheet in the
As Found section.
12.
The RF is now displayed
in the worksheet. If the RF is between
0.98 and 1.02, the audit is complete.
13.
Close the Trigger Cals
and Query Data windows.
14.
Save the Gas calibration
worksheet.
15.
If the RF is not within
specification continue with the Analyzer Calibration procedure.
Analyzer Calibration
1. This procedure will be used to calibrate the
analyzer and obtain a corrected RF value for the NOy*/NOy analyzer.
2.
Enter the As Found data
for NOy Zero in the As Left section for NOy Zero.
3.
On Site Manager go to
the Tools tab and select Trigger Cals.
4.
In the Trigger Cals menu
select NOy*/NOy Zero and
wait 5 minutes for data to be captured for First Light use.
5.
In the Trigger Cals Menu
select NOy*/NOy NO GRC
Point 1 and press Start Calibration.
6.
Under the Tools tab
select Query 1-Minute Data.
7.
In the Query Data Tool
Menu select the Air MFC, Gas MFC, NOy* and NOy.
8.
Wait 13 minutes and
verify the data for NOy* and NOy
are stable (+/- 0.2 ppb). If the query
data numbers are approximately equal to the number on Site Manager, then the
data is stable and an average can be taken.
9.
Adjust the instrument to
the Actual Expected value from the As Found section of the worksheet.
a.
On “C” or “CTL” class
analyzers the PMT can be adjusted by taking the top off of the analyzer. With the top of the analyzer off look on the
right side of the bulkhead at the front.
There is a blue box with an orange grommet on the top. Inside the grommet is the PMT adjustment
screw. Some CTL model analyzers have
been modified so that the PMT can be adjusted through the front panel. Adjust the analyzer until the NO channel on
the analyzer or NOy* on Site Manager is approximately
equal to the Actual Expected value from the As Found section worksheet.
10.
When the analyzer
calibration is complete, let the analyzer stabilize for 5 minutes.
11.
On the Query 1-Minute
Data tool press Get Data.
12.
Enter the Air MFC, Gas
MFC, NOy* and NOy data in
the appropriate blank for the NOy*/NOy NO GRC Point 1 on the Gas Calibration Worksheet in the
As Left section.
13.
The RF is now displayed
in the worksheet. If the RF is between
0.98 and 1.02, the calibration is complete.
If the RF is not within specification, repeat the procedure again.
14.
When the instrument is
finished being calibrated make sure to put it back
into the Run mode.
15.
Close the Trigger Cals
and Query Data windows.
16.
Save the Gas Calibration
worksheet.
NOy*/NOy NO2 Conversion
Efficiency Audit
1.
This procedure will
obtain the current RF value for the NO2 Conversion Efficiency.
2.
Open the Gas Calibration
Worksheet and go to the NO2 Conv Eff Worksheet tab. Enter the correct NO and NO2 concentrations
(found on the gas cylinder) in the blanks provided.
3.
An NO audit of the
analyzer has to be completed before the NO2 conversion efficiency can be
completed. You may use that day’s
information if available. If it is
available enter the information and start with Step 15. Otherwise continue with the next Step.
4.
On the Site Manager
screen go to the Tools tab and select Trigger Cals.
5.
In the Trigger Cals menu
select NOy Zero and press Start Calibration.
6.
Under the Tools tab
select Query 1-Minute Data.
7.
In the query data tool
menu select the Air MFC, Gas MFC, NOy* and NOy.
8.
Wait 13 minutes and
verify the Zeros for NOy* and NOy
are stable (+/-0.1 ppb). Contact
9.
Enter the Air MFC, NOy* and NOy data in the
appropriate blank for the NOy Zero on the NO2 Conv
Eff Worksheet in the NOy*/NOy
Analyzer Response section.
10. Go to Trigger Cals and press Stop Calibration
then select NOy*/NOy NO GRC
Point 1 and press Start Calibration.
11. Wait 13 minutes and verify the data for NOy* and NOy are stable (+/-
0.2ppb), then press Get Data.
12. Enter the Air MFC, Gas MFC, NOy*
and NOy data in the appropriate blanks for the NOy*/NOy NO GRC Point 1 on the
NO2 Conv Eff Worksheet in the NOy*/NOy Analyzer Response section.
13. The RF is now displayed at the far right of the
worksheet.
14. Save the Gas Calibration Worksheet.
15. In the Trigger Cals menu select NOy Zero and press Start Calibration.
16. Under the Tools tab select Query 1-Minute Data.
17. In the query data tool menu select the Air MFC,
Gas MFC, NOy* and NOy.
18. Wait 13 minutes and verify the Zeros for NOy* and NOy are stable (+/-0.1
ppb). Contact
19. Enter the Air MFC, NOy*
and NOy data in the appropriate blank for the NOy Zero on the NO2 Conv Eff Worksheet in the NOy*/NOy NO2 Conversion
Efficiency section.
20. Go to Trigger Cals and press Stop Calibration
then select NOy*/NOy NO2
GRC Point 1 and press Start Calibration.
21. Wait 13 minutes and verify the data for NOy* and NOy are stable (+/-
0.2ppb), then press Get Data.
22. Enter the Air MFC, Gas MFC, NOy*
and NOy data in the appropriate blanks for the NO/NO2
NO2 GRC Point 1 on the NO2 Conv Eff Worksheet in the NOy*/NOy NO2 Conversion Efficiency section.
23. The RF is now displayed at the far right of the
worksheet.
24. If the RF is less than 0.95 it is out of spec
and the RF will turn red.
25. Contact
26. Close the Trigger Cals and Query Data windows.
27. Save the Gas Calibration Worksheet.