Frederick, Maryland Air Quality
Frederick County, Maryland (MD)
→ Stableover 10 years
10-Year AQI Trend
The solid line shows the median AQI each year. The dashed line shows the 90th percentile (worst 10% of days).
Air Quality Day Breakdown
Number of days per year in each EPA AQI category. Green = Good (AQI 0-50), Yellow = Moderate (51-100), Orange = Unhealthy for Sensitive Groups (101-150), Red = Unhealthy or worse (151+).
Year-by-Year Data
| Year | Median AQI | 90th Pct | Max AQI | Good Days | Moderate | Unhealthy+ | Pollutant |
|---|---|---|---|---|---|---|---|
| 2023 | 44 | 77 | 136 | 167 | 59 | 6 | Ozone |
| 2022 | 41 | 51 | 115 | 212 | 23 | 1 | Ozone |
| 2021 | 41 | 58 | 126 | 207 | 36 | 1 | Ozone |
| 2020 | 40 | 49 | 90 | 217 | 20 | 0 | Ozone |
| 2019 | 44 | 58 | 112 | 198 | 44 | 1 | Ozone |
| 2018 | 41 | 61 | 100 | 204 | 41 | 0 | Ozone |
| 2017 | 42 | 64 | 105 | 190 | 51 | 2 | Ozone |
| 2016 | 43 | 74 | 122 | 151 | 57 | 3 | Ozone |
| 2015 | 44 | 67 | 119 | 160 | 48 | 1 | Ozone |
| 2014 | 42 | 58 | 80 | 171 | 37 | 0 | Ozone |
What This Means for Frederick County Residents
Frederick, Maryland has received an Air Quality Grade of B (65/100) based on a decade of monitoring data from the EPA's air quality monitoring program. The current median AQI of 44 falls in the "Good" range.
The primary pollutant affecting this area is Ground-Level Ozone. Over the past 5 years, this area has averaged 2 unhealthy air quality days per year — days when sensitive groups (children, elderly, those with respiratory conditions) should limit outdoor activity. The American Lung Association's State of the Air report provides additional context on long-term health risks from air pollution exposure.
Related Cities in Maryland
Frequently Asked Questions
Frederick, Maryland has a current median AQI of 44, which falls in the "Good" range. The area has received an Air Quality Grade of B (65/100) based on 10 years of EPA monitoring data.
Air quality in Frederick, Maryland is stable over the past decade. The median AQI has changed by +2 points from 2014 to 2023.
Frederick, Maryland averages 2 unhealthy air quality days per year over the past 5 years. On these days, sensitive groups including children, the elderly, and those with respiratory conditions should limit outdoor activity.
The primary pollutant affecting Frederick, Maryland is Ground-Level Ozone. This is the dominant contributor to elevated AQI readings in the Frederick County area.
Frederick, Maryland averages 2 unhealthy air days per year. This is relatively low, making it a reasonable choice for asthma sufferers. The primary pollutant is Ground-Level Ozone, which is a known asthma trigger.
With a median AQI of 44 (Good), outdoor exercise in Frederick, Maryland is generally safe year-round. Frederick, Maryland averages 2 days per year when athletes should move workouts indoors.