Indiana has a large network of outdoor monitors which measure for six common pollutants . These pollutants include carbon monoxide (CO), lead (Pb), nitrogen dioxide (NO2), ozone (O3), particulate matter (PM), and sulfur dioxide (SO2). This page provides reports on long-term trends.
IDEM divided the state into eight regions to provide readers with a more detailed breakdown of data where they live and work. The regions are not tied to policies or laws. Each report covers a period of 30 years. A region may not monitor for all six pollutants. All available data is included for each region.
Historical Air Quality Data
- Northwest Indiana Trend Reports [ZIP]
- North Central Indiana Trend Reports [ZIP]
- Northeast Indiana Trend Reports [ZIP]
- West Central Indiana Trend Reports [ZIP]
- Central Indiana Trend Reports [ZIP]
- East Central Indiana Trend Reports [ZIP]
- Southwest Indiana Trend Reports [ZIP]
- Southeast Indiana Trend Reports [ZIP]