In EGLE’s Air Quality Division, the nose knows

Every year Air Quality Division (AQD) staff respond to hundreds of air quality complaints from Michigan residents. Complaints are typically about strong odors, smoke, and dust from industrial sources. In 2024, almost 1,700 air quality complaints have been lodged, with 84% of complaints stating strong odors are impacting them. Many complainants voice concerns about health impacts, like headaches and nausea. Studies have shown that some odors can have health impacts, so investigating odor complaints is important. Examining diverse odors in variable situations requires staff to be trained to understand odors and how to analyze and document them.

An inspector will use a defined Odor Scale to document an odor investigation. This scale and its proper implementation establish the foundation for odor investigations. The 0-5 scale requires the inspector to rate the odor from “0 – Non-detect” to “5 – odor so strong as to be overpowering and intolerable for any length.” Staff also incorporate the frequency and duration of the odors into their investigation. But how are these determinations made? This is where Odor School comes in.