The current version of US EPA Clean Air Markets Monitoring Data Checking software (MDC) is MDC v4.2.46, revised as of March 15, 2004. This version of MDC supersedes MDC v4.1.42 which was previously posted in December, 2003.
This new version is being released to provide significant changes to the QA Status Evaluation portion of MDC Hourly. Unlike previous versions, it does not rely on RTs 697, 698 or 699 to determine test deadline extensions or test exemptions due to non-QA operating quarters, linearity exemptions due to low span values, or grace period extensions. This version also checks the linearity status of both ranges of dual range analyzer components (NOXA, SO2A, etc.) to make sure required tests were performed. MDC v4.2.46 also includes minor fixes to problems that were reported in the previous version.