Teledyne 9110T References, Certification Procedures of Working Standards, That Appendix

Model 9110T NOx Analyzer EPA Protocol Calibration

To establish traceability, data must be obtained routinely by repeated measurements of standard reference samples (primary, secondary, and/or working standards). More specifically, working calibration standards must be traceable to standards of higher accuracy.

10.9.1.1. Certification Procedures of Working Standards

This procedure requires the use of calibrated NO gas traceable to an NIST-SRM SRM and the gas phase titration calibration procedure (Section 10.5) to calibrate the NO, NOX, and NO2 responses of the analyzer. Also the efficiency of the analyzer’s NO2 converter must be determined (Section 9.1.4).

Generate several NO concentrations by diluting the NO working standard. Use the nominal NO cylinder concentration, [NO]NOM, to calculate the diluted concentrations. Plot the analyzer NO response (in ppm) versus the nominal diluted NO concentration and determine the slope, SNOM. Calculate the NO concentration of the working standard [NO]STD from:

Equation 10-11

[NO]STD = [NO]NOM x SNOM

A more detailed procedure is presented in Reference 1 (Section 10.10).

10.9.1.2. Other Methods of Establishing Traceability

Methods of establishing traceability are:

∙Using a NO working standard traced to NIST NO2 standard.

∙Using a NO2 working standard traced to NIST NO2 standard.

∙Using a NO2 working standard traced to NIST NO standard.

IMPORTANT	IMPACT ON READINGS OR DATA
	If the NO2 impurity in the NO cylinder, [NO2]imp is greater than the 1 ppm
	value allowed in the calibration procedure, check that the NO delivery
	system is not the source of contamination before discarding the NO
	standard.
	For further information on calibration by GPT and NO2 permeation
	devices, refer to part 50 of Section 1, Title 40 CFR, Appendix F Reference
	13 of that Appendix.

10.10. REFERENCES

1.Environmental Protection Agency, Title 40, Code of Federal Regulations, Part 50, Appendix F, Measurement Principle and Calibration Procedure for the Measurement of Nitrogen Dioxide in the Atmosphere (Gas Phase Chemiluminescence), Federal Register, 41 (232), 52688-52692, December 1976 (as amended at 48 FR 2529, Jan 20, 1983).

2.Ellis, Elizabeth C. Technical Assistance Document for the Chemiluminescence Measurement of Nitrogen Dioxide, U.S. Environmental Protection Agency, Research Triangle Park, NC. 83 pages, December 1975. Available online at http://www.epa.gov/ttn/amtic/files/ambient/criteria/reldocs/4-75-003.pdf.

3.Environmental Protection Agency, Title 40, Code of Federal Regulations, Part 58, Appendix A, Measurement Principle and Calibration Procedure for the Measurement of Nitrogen Dioxide in the

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