Thousands of people in communities across parts of Georgia (including Dalton, Adrian, and Louisville) and Tennessee (including Chattanooga, Dunlap, and Tracy City) have been advised to stay indoors, after the Environmental Protection Agency (EPA) recorded that fine particle pollution (PM2.5) had reached “unhealthy” levels, as of January 22, 2026, at 2.45 a.m., according to the AirNow Map.
Why Does This Matter
When local air quality readings are classified as “unhealthy,” the EPA warns that everyone in the affected area might begin to experience certain health effects, ranging from coughing and eye, throat, and nose irritation to chest tightness and shortness of breath.
Members of sensitive groups, which include children, the elderly, and people with existing heart and lung health conditions, may experience more serious health effects.
What To Do When Air Is “Unhealthy”
When air quality reaches “unhealthy” levels, the EPA advises everyone in the affected area to take more breaks during outdoor activities, reduce activity intensity, and move longer or more strenuous activities indoors when possible, until the air quality improves.
Local health agencies, such as New York City’s Department of Health, recommend wearing a properly fitted respirator (such as an N95 or KN95) to help reduce exposure when someone must remain outdoors for extended periods.
Individuals in sensitive groups should be particularly cautious, as elevated PM2.5 levels can exacerbate or trigger heart and lung issues.
The EPA also advises checking real‑time conditions and forecasts to plan activities for when air quality is better, and to keep medications and asthma action plans current for those with respiratory conditions
How Air Pollution Affects Health
According to the EPA, fine particulate matter—known as PM2.5—consists of “fine inhalable particles, with diameters that are generally 2.5 micrometers and smaller.”
Because of their small size, PM2.5 can penetrate deep into the lungs and enter the bloodstream, which is why exposure to PM2.5 can trigger a range of health effects, including asthma, decreased lung function, and increased respiratory issues, and can contribute to serious outcomes for people with cardiovascular conditions.
What Causes ‘Unhealthy’ Air Quality
PM2.5 comes from multiple sources, including direct emissions and the formation of particles in the atmosphere from gases. According to the EPA, common sources of increased PM2.5 include power plants, industrial activities, vehicles, wood burning, and wildfires.
How the EPA Measures Air Quality
The EPA uses the Air Quality Index (AQI) to measure and report the air quality across America. The AQI uses a scale and six categories to establish the health concern levels, with the higher the AQI value, the greater the level of air pollution and the greater the health concern.
The categories are:
- Good (0–50): Air quality is satisfactory, and air pollution poses little or no risk
- Moderate (51–100): Air quality is acceptable; some pollutants may be a moderate health concern for a very small number of unusually sensitive people
- Unhealthy for Sensitive Groups (101–150): Members of sensitive groups may experience health effects, but the general public is less likely to be affected
- Unhealthy (151–200): Some members of the general public may experience health effects, and members of sensitive groups may experience more serious effects
- Very Unhealthy (201–300): A health alert is issued as the risk of health effects is increased for everyone
- Hazardous (301–500): A health warning of emergency conditions is issued as everyone is more likely to be affected.