Teledyne GFC 7001E Auditing Procedure, Precision Calibration Procedures, Calibration Audit

EPA Calibration Protocol Model GFC7001E Carbon Dioxide Analyzer

Alternate units, make sure ppm units are selected for EPA monitoring. See Section 6.6.4. The analyzer should be calibrated on the same range used for monitoring.

10.3.1.PRECISION CALIBRATION PROCEDURES

To perform a precision calibration during the instrument set up, the input sources of zero air and sample gas and procedures should conform to those described in Section Error! Reference source not found. for analyzers with no valve options or with an IZS valve option installed and Section 9.3 for analyzers with Z/S options installed.

10.4.AUDITING PROCEDURE

An audit is an independent assessment of the accuracy of data. Independence is achieved by having the audit made by an operator other than the one conducting the routine field measurements and by using audit standards and equipment different from those routinely used in monitoring. The audit should be a true assessment of the measurement process under normal operations without any special preparation or adjustment of the system. Routine quality control checks conducted by the operator are necessary for obtaining and reporting good quality data, but they are not considered part of the auditing procedure. Audits are recommended once per quarter, but frequency may be determined by applicable regulations and end use of the data.

Refer to The Q.A. Handbook1 Volume II, Part 1 Section 16 (for a more detailed description).

10.4.1.CALIBRATION AUDIT

A calibration audit consists of challenging the GFC 7001E/EM with known concentrations of CO. The difference between the known concentration and the analyzer response is obtained, and an estimate of the analyzer's accuracy is determined.

The recommended audit schedule depends on the purpose for which the monitoring data are being collected. For example, Appendix A, 40 CFR 585 requires that each analyzer in State and Local Air Monitoring Network Plan (SLAMS) be audited at least once a year. Each agency must audit 25% of the reference or equivalent analyzers each quarter. If an agency operates less than four reference or equivalent analyzers, it must randomly select analyzers for reauditing so that one analyzer will be audited each calendar quarter and each analyzer will be audited at least once a year.

Appendix B, 40 CFR 585 requires that each Prevention of Significant Deterioration (PSD) reference or equivalent analyzer be audited at least once a sampling quarter. Results of these audits are used to estimate the accuracy of ambient air data.

10.4.2.DATA REDUCTION AUDIT

A data reduction audit involves transcribing analyzer data and determining if the collected data is within the control limits, generally 2 ppm between the analyzer response and the audit value. The resulting values are recorded on the SAROAD form. If data exceeds 2 ppm, check all of the remaining data in the 2-week period.

Teledyne Analytical Instruments 223