Читать книгу Continuous Emission Monitoring - James A. Jahnke - Страница 51

U.S. CEM programs have been written so that gaseous pollutant emission data are traceable to National Institute of Standards and Technology (NIST) standard reference materials (SRMs). Certified calibration gases, traceability back to SRMs, are used for this purpose when conducting the required quarterly cylinder gas audit of Part 60 Appendix F – Procedure 1 and the Part 75 daily calibration verifications and quarterly linearity tests. The traceability protocols are found in the document: EPA Traceability Protocol for Assay and Certification of Gaseous Calibration Standards (U.S. EPA 2012).

In addition to the traceability protocol, the Clean Air Markets Division instituted the Protocol Gas Verification Program (PGVP) designed to ensure the accuracy of protocol calibration gases – a program that has done much to ensure the quality of CEM data [see 40 CFR 75.21(g)(6) and (7)]. To sell gases as “protocol” gases, gas suppliers must adhere to traceability protocol procedures and participate in the PGVP program. In the program, protocol gases are purchased by users, who instead of using them, send the gases to NIST for analysis against NIST standard reference materials. The results of the analyses are made publicly available, which provides an incentive for gas vendors to perform well on the blind audits. Failure to perform well can result in a loss of both credibility and customers in this competitive and lucrative business.