Regional Office Building Air Monitoring Station, Des Plaines, Illinois

The Regional Office Building air monitoring station is located at 9511 W. Harrison Street in Des Plaines, Illinois, within Cook County. This station is part of the Illinois Environmental Protection Agency's air quality monitoring network, which supports the US EPA's Air Quality System (AQS). It serves the densely populated Chicago metropolitan area, contributing to the assessment of criteria pollutants and other atmospheric parameters. The station operates under the regulatory framework of the US Clean Air Act and the National Ambient Air Quality Standards (NAAQS). As part of the Illinois EPA network, it follows standardized siting and reporting protocols to ensure data representativeness and continuity. The station's last reported sample date is September 30, 2025, indicating ongoing operations. This monitoring station plays a vital role in tracking air quality trends in northeastern Illinois. Its data supports public health advisories, regulatory compliance assessments, and regional air quality management. The station's location in a suburban office area provides representative measurements for population exposure and urban background conditions.

The station is situated in a mixed suburban and industrial region near Chicago O'Hare International Airport. Local air quality is influenced by transportation emissions, industrial activities, and meteorological patterns from Lake Michigan. The station's measurements help characterize ozone, particulate matter, and other pollutants in a region that has historically faced challenges meeting NAAQS for ozone and PM2.5. Its data contributes to the broader understanding of urban air pollution dynamics and the effectiveness of emission reduction strategies.