What are the QA/QC requirements for EPA-compliant Continuous Emission Monitoring Systems?

CEMS QA/QC per 40 CFR Part 60/75: daily calibration drift check (zero and span within allowable limits, typically +/-2.5%), Cylinder Gas Audit (quarterly, using EPA Protocol gases), Relative Accuracy Test Audit (RATA - annual, compare CEMS to reference method), Bias Adjustment Factor (calculated from RATA), and data validation procedures. Data reporting: valid hour requirements, substitution data rules for missing data, electronic reporting via ECMPS. Maintain calibration gas certificates, test records, and maintenance logs. Address out-of-control conditions per regulation. CEMS downtime affects compliance; redundancy considerations for critical applications.