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Pre-generated AQS Data Files

Published by U.S. EPA Office of Air and Radiation (OAR) - Office of Air Quality Planning and Standards (OAQPS) | U.S. Environmental Protection Agency | Catalog Last Checked: July 07, 2026 at 11:39 AM | Dataset Last Updated: January 01, 2014
TThis page contains large files of data intended for use by people who understand the EPA ambient air quality monitoring program and data. Some contain data summarized on an annual basis (annual summary files), some contain data summarized on a daily basis (daily summary), and some contain raw data (sample data as reported). These are the standard time aggregations EPA calculates and stores (we do not have monthly data). All but the annual summary have data files grouped by parameter: Criteria Gases, Particulates, Meteorological, Toxics, Ozone Precursors, and Lead Blanks (Blanks are empty cannisters that are measured for speciation quality assurance reasons)

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