HAMMOND CAAP- Hammond- 141st St. Air Monitoring Station, Hammond, Indiana

HAMMOND CAAP- Hammond- 141st St. is an air monitoring station located at 1300 141st Street in Hammond, Indiana, within Lake County. The station is operated by the Indiana Department of Environmental Management's Office of Air Quality and is part of the broader US EPA Air Quality System (AQS) network, which monitors criteria pollutants and other atmospheric parameters across the United States. The station reports to the Indiana Department of Environmental Management and provides continuous ambient air quality data. As part of the national AQS network, it follows EPA-mandated siting criteria and quality assurance procedures to ensure representativeness and data reliability. The station's last reported sample date is September 28, 2025, indicating ongoing operations. Located in an industrial and urban area near the Illinois border, this station contributes to understanding local air quality impacts from sources such as transportation, industry, and regional pollution transport. Data from this station supports regulatory compliance with National Ambient Air Quality Standards (NAAQS) and informs public health advisories.

The station is situated in Hammond, Indiana, a city with a mix of industrial facilities, major highways, and proximity to Chicago. Air monitoring in this region focuses on criteria pollutants like ozone, particulate matter, and nitrogen dioxide, which are influenced by local emissions and regional transport. The station's siting is designed to capture representative ambient concentrations for population exposure assessment and regulatory compliance.