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Clean Air Markets

Protocol Gas Verification Program Audit Reports

View the full reports from the 2010 and 2013 EPA protocol gas audits. The audits tested the EPA protocol gases that are used to calibrate continuous emission monitoring systems (CEMS), and the instruments used in EPA reference methods.

View the Protocol Gas Verification Program for related information.

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.

2010 EPA Protocol Gas Audit (PDF)(58 pp, 676 K)
2013 EPA Protocol Gas Audit (PDF)(59 pp, 3 MB)