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Clean Air Markets

Control Chart Methodology for Detecting Under-reported Emissions

EPA has begun to apply the control chart methodology described in this paper to electronically identify the potential development of sampling system in-leakage (or other monitoring system problems) that result in the under-measurement of emissions data. This paper describes the steps that the Agency intends to use to evaluate CO2 data for indications of data problems. Return to Emissions Monitoring and Reporting for more emissions monitoring resources.

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