Hamilton, Tennessee Air Quality Today
AirHistory tracks long-run EPA monitoring rather than live readings, so for the live number check AirNow.gov below. As a baseline, Hamilton, Tennessee's most recent EPA year (2023) posted a median AQI of 51 (Moderate) against a 5-year median of 49 and an overall Grade of C. The dominant pollutant is Fine Particulate Matter (PM2.5), which tells you which days are most likely to spike.
Check Today's Live AQI in Hamilton, Tennessee
AirHistory is built on 10 years of EPA Air Quality System records, so it shows you what air quality in Hamilton, Tennessee typically looks like — not the live reading for this exact hour. For today's real-time AQI, check AirNow.gov (the EPA's official live index) or the AirNow Fire and Smoke Map during wildfire season.
That said, the history is the best predictor of a normal day. In 2023, Hamilton, Tennessee posted a median AQI of 51 (Moderate), with 175 "Good" days and 3 days that crossed into "Unhealthy for Sensitive Groups" or worse. The dominant pollutant, Fine Particulate Matter (PM2.5), is the one most likely to push today's number up — Fine particulate matter — particles less than 2.5 micrometers across — comes mostly from combustion: vehicle exhaust, wildfire smoke, residential wood burning, and industrial emissions. Because these particles are small enough to enter the bloodstream, PM2.5 is the pollutant most strongly linked to cardiovascular disease, respiratory illness, and premature death.
Hamilton, Tennessee Air Quality Snapshot
| Air Quality Grade | C55/100 |
| 5-Year Median AQI | 49 (Good) |
| Most Recent Median AQI (2023) | 51 (Moderate) |
| Dominant Pollutant | Fine Particulate Matter (PM2.5) |
| 10-Year Trend | Worsening (+0.68 AQI/yr) |
| Unhealthy Days (last 5 yr) | 6 |
| National Rank (cleanest = #1) | #917 of 1,020 (90th most polluted percentile) |
| Tennessee Rank | #21 of 23 |
What Does the C Grade Mean?
Hamilton, Tennessee earns a C — air quality is fair, but not great. With a 5-year median AQI of 49, the city sees a meaningful number of "Moderate" days each year, when the EPA flags air as a concern for unusually sensitive people.
Hamilton, Tennessee's 5-year median AQI of 49 is 8 points above the national average of 41 — meaningfully more polluted than the typical U.S. metro tracked here. Within Tennessee, Hamilton, Tennessee runs more polluted than the state average of 40 — local sources or geography are concentrating pollution above the state's typical reading.
For context within Tennessee: Roane, Tennessee currently holds the state's cleanest grade (A, AQI 36), while Shelby, Tennessee sits at the bottom (C, AQI 50).
What's in Hamilton, Tennessee's Air?
The dominant pollutant in Hamilton, Tennessee is Fine Particulate Matter (PM2.5). Fine particulate matter — particles less than 2.5 micrometers across — comes mostly from combustion: vehicle exhaust, wildfire smoke, residential wood burning, and industrial emissions. Because these particles are small enough to enter the bloodstream, PM2.5 is the pollutant most strongly linked to cardiovascular disease, respiratory illness, and premature death.
Days by Dominant Pollutant (2023)
| Pollutant | Days as Dominant | Share of Year |
|---|---|---|
| Fine Particulate Matter (PM2.5) | 258 | 71% |
| Ground-Level Ozone | 107 | 29% |
Is the Air Getting Better or Worse?
Air quality in Hamilton, Tennessee has been getting worse over the past decade, with median AQI climbing by roughly 0.7 points per year. That bucks the national trend of broad improvement, and most often reflects either growing wildfire smoke exposure (particularly across the West) or rising local emissions from population and freight growth.
In 2014, Hamilton, Tennessee posted a median AQI of 44. By 2023 that figure was 51 — a rise of 7 AQI points dirtier across 10 years of EPA records.
Year-by-Year AQI in Hamilton, Tennessee
| Year | Median AQI | Good Days | Unhealthy Days | Dominant Pollutant |
|---|---|---|---|---|
| 2014 | 44 | 193 | 1 | Ozone |
| 2015 | 43 | 211 | 3 | Ozone |
| 2016 | 47 | 179 | 3 | Ozone |
| 2017 | 51 | 156 | 2 | PM2.5 |
| 2018 | 48 | 193 | 1 | PM2.5 |
| 2019 | 51 | 181 | 0 | PM2.5 |
| 2020 | 46 | 219 | 1 | PM2.5 |
| 2021 | 48 | 191 | 1 | PM2.5 |
| 2022 | 51 | 169 | 1 | PM2.5 |
| 2023 | 51 | 175 | 3 | PM2.5 |
Health Context for Hamilton, Tennessee
Across the past five years, this area has logged just 6 days where AQI rose into the "Unhealthy for Sensitive Groups" range or worse — about 1 days per year, or roughly one every other month. That is a low count by national standards.
Healthy adults can continue normal outdoor activity in most weather, but should pay attention to AQI alerts during the worst pollution windows. People with asthma, heart disease, or pregnancy should reduce prolonged or intense outdoor exertion on flagged days, and consider running an indoor HEPA air cleaner during peak season. Because PM2.5 penetrates deep into the lungs and bloodstream, an N95 or KN95 mask provides meaningful protection on smoky or high-particulate days — surgical masks do not.
How This Grade Is Calculated
The AirHistory Air Quality Grade combines four signals: the 5-year median AQI (40% of the score), the 10-year trend direction (30%), the count of unhealthy days per year (20%), and the dominant pollutant type (10%). All four come directly from the EPA Air Quality System (AQS), which aggregates readings from federally certified monitors. Read the full methodology.
More about Hamilton, Tennessee
Hamilton, Tennessee has an Air Quality Grade of C (fair) with a 5-year median AQI of 49. The dominant pollutant is Fine Particulate Matter (PM2.5), and air quality has been worsening over the past decade.
The data source behind this answer is the EPA Air Quality System (AQS). Every figure on the page traces back to that source; the methodology page describes the inputs and the refresh cadence in full detail.
A practical caveat: the headline answer above reflects the most recent the EPA Air Quality System (AQS) vintage; underlying data is often revised for months after first publication, and the right reference for any specific decision is whichever vintage is current at the time of the decision. The as-of date is stamped on every page.
Source: EPA Outdoor Air Quality Data, 2026.