Short name:
NOx Box

Full name:
Chemiluminescence NO-NO2-NOx Analyzer

What is being measured:
NOx Concentrations

Sampling Protocol:
Online

Manufacturer:
Thermo Environmental

Model:
Model 42

Instrument year :
1989

Data recording software:
Labview Program

Data analysis software:
Custom Excel Program

Raw data time resolution:
1s

Analysis data averaging:
60s

Detection limit:
0.1 ppb

Sensitivity to temperature (and correction method, if applicable): :
N/A

Sensitivity to relative humidity (and correction method, if applicable): :
N/A

Sampling method:
Direct gas sampling

Sample preparation method:
Filter particle contents before sampling; One of the measuring streams is flowing through catalyst system to convert NOx to NO

Sample residence time (chamber to instrument) (seconds):

Length of tubing (cm):

Instrument flow rate:

Tubing inner diameter:
1/4'' OD; 0.152'' ID

Tubing material:
FEP Teflon

Chemical identification method:
NO concentration is determined by Chemiluminescence method; NOx concentration is determined by the same method from another sample stream which flows through the catalyst box, assuming the catalyst can convert 100% of the NO2 into NO.

Data analysis method:
The raw signal is logged by the custom Labview program every second and is averaged to 1 min of the time range. Finally the data is pulled out by a custom Excel script.

Quantification method:
[NO2] = [NOx] - [NO].

Calibration method:
Standard NO and NOx gas with known concentrations was introduced into the instrument and calibration factor is calculated based on the comparison. THIS IS DONE EVERYTIME BEFORE AN EXPERIMENT.

Calibration drift estimate:
No estimate

Calibration schedule:
As Needed

Uncertainty estimation method:
N/A

Known interferences:
N/A

Link to supplemental information:
N/A

Additional notes:
N/A

Measurement uncertainty:
(a) Local_Time (N/A); (b) Experimental_Time (N/A); (c)NO_Concentration (+/- ?%); (d) NO2_Concentration (+/- ?%); (e) NOx_Concentration (+/- ?%)

Measurement units:
(a) Local_Time (N/A); (b) Experimental_Time (N/A); (c)NO_Concentration (ppb); (d) NO2_Concentration (ppb); (e) NOx_Concentration (ppb)