An official website of the United States government.

We've made some changes to If the information you are looking for is not here, you may be able to find it on the EPA Web Archive or the January 19, 2017 Web Snapshot.

EPA in Illinois

Outdoor Air Monitoring Data in the Willowbrook Community

EPA will be monitoring outdoor air near the Sterigenics facility to better understand the levels of ethylene oxide (EtO) in the air. The first monitors began collecting air samples on Nov. 13, 2018.  Read the Quality Assurance Project Plan for Field Sampling Plan for Ambient Air Ethylene Oxide Monitoring near Sterigenics Facility, Willowbrook, IL

Air samples will be collected every three days, over a 24-hour time frame, for three full months.

See the full available data set below or review the data by monitoring date with general wind direction and speed for each sampling period.

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.