Glendale Heights, Illinois Air Quality

Glendale Heights air quality today — the AQI, the main pollutant, and whether it’s safe to exercise outside right now

Glendale Heights, IL · Air quality right now

The air quality index in Glendale Heights, IL is 36 (Good) right now — safe for outdoor activity.

Is it safe to be outside in Glendale Heights today?

AQI 36 Yes — air quality is Good

Air is clean — great for outdoor activity.Main pollutant: PM2.5Observed 10:00 AM CDT

Pollutants right now

ExerciseOK to run — no air-quality limits on outdoor exercise.

How to read Glendale Heights’s air quality

Guides: The AQI Scale, Explained · Air Quality Alerts, Decoded · How to Read a Wildfire Smoke Map · Why Wildfire Smoke Travels 1,000 Miles.

Air quality over time in Glendale Heights

Across the EPA’s county records from 2020 to 2025, Glendale Heights’s cleanest year was 2025 (median AQI 42) and its most polluted was 2023 (median AQI 53); the typical (median) day has held roughly steady since 2020.

Glendale Heights’s county air-quality record by year — the median and days in each AQI category, from the EPA’s Annual AQI by County summaries.
YearMedian AQIUnhealthy+Main pollutantUSGModerateGood
2020471PM2.53149213
2021510PM2.52184179
2022470PM2.51165199
2023536PM2.511202146
2024450PM2.50136230
2025421PM2.55126233

“USG” is Unhealthy for Sensitive Groups (AQI 101–150); “Unhealthy+” combines the Unhealthy, Very Unhealthy, and Hazardous days. In 2024 the EPA tightened the annual fine-particle (PM2.5) standard to 9 µg/m³ from the previous 12 µg/m³, so counties near the old limit read worse against the new one. Source: EPA AQS annual summaries, 20202025.

Frequently asked

What was the worst year for air quality in Glendale Heights?
In the EPA's 2020–2025 county records, 2023 had the most days above AQI 100: 17 days (11 Unhealthy for Sensitive Groups, 6 Unhealthy or worse). It also had the highest median AQI, 53.
How many unhealthy air days does Glendale Heights have?
Across 2020–2025, 1% of the days reported for Glendale Heights's county had an AQI above 100 (30 of 2192), about 5 days a year. 2025 had 6 days.
What's the main air pollutant in Glendale Heights?
PM2.5: it drove Glendale Heights's county AQI on the most days in every year of the EPA's 2020–2025 records.