Indiana has an extensive network of ambient air monitors measuring air quality across the state. Each region on the map below provides a link to a presentation with historical monitoring data trend charts for the six criteria pollutants regulated by the Clean Air Act. The six criteria pollutants are particulate matter, sulfur dioxide, nitrogen dioxide, ozone, carbon monoxide and lead. Each region does not necessarily monitor for each of the six criteria pollutants but all available data for each region is included in the presentation. These regions were developed to provide information that is more detailed so that readers can focus on the area of the state where they live and work. These regions have no policy or legal implications. Our goal is to present historical air quality data in an easy to read format.
Historical Air Quality Data
- Central Regional Data [PDF]
- Central Southeastern Data [PDF]
- Central Southwestern Data [PDF]
- East Central Data [PDF]
- Lower North Central Regional Data [PDF]
- Lower Northwestern Regional Data [PDF]
- North Central Regional Data [PDF]
- Northeastern Regional Data [PDF]
- Northwestern Regional Data [PDF]
- Southeastern Data [PDF]
- Southwestern Data [PDF]
- West Central Regional Data [PDF]