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Clean Air Status and Trends Network (CASTNET)

CASTNET is a national monitoring network established to assess trends in pollutant concentrations, atmospheric deposition, and ecological effects due to changes in air pollutant emissions.

Clean Air Status and Trends Network (CASTNET)

COVID-19 Update

We are working closely with CASTNET operators, calibrators, and laboratory personnel to protect their safety and the health of their families. During an emergency or COOP, ambient air monitoring programs are a mission essential function and should continue, but we may experience gaps in the data record as local directives prohibit operators from visiting the sites. Currently, all CASTNET sites are operating following standard procedures and schedules. Data will continue to be flagged following the procedures in the QAPP and completeness criteria applied to aggregate data products. Updates will be provided if we experience a degradation in service.