Air Quality Index Basics

The Air Quality Index (AQI) is a scale used to convey the effect of local air quality on public health. 

The AQI represents the amount of an air pollutant on a scale from 0-500. The higher the value the greater the level of pollution and potential health risk. The values are sorted into six color-coded categories ranging from "Good" (1-50) to "Hazardous" (301-500). While there is no "healthy" amount of air pollution, any AQI value below 100 is considered to be acceptable for public health. 
 

AQI Value Category & Description
1-50 Good: Air quality is satisfactory, and air pollution poses little or no risk to public health.
51-100 Moderate: Air quality is considered acceptable. However, there may be a risk for some people, particularly those who are unusually sensitive to air pollution.
101-150 Unhealthy for Sensitive Groups: Members of sensitive groups may experience health effects. Others are less likely to be affected.
151-200 Unhealthy: Any member of the general public may experience health effects; members of sensitive groups may experience more serious health effects
201-300 Very Unhealthy: Health alert. The risk of health effects is increased for everyone.
301 and above Hazardous: Health warning of emergency conditions. Everyone is more likely to be affected.

AQI Pollutants

The AQI is calculated for five common air pollutants monitored in our air: ground-level ozone, particle pollution, carbon monoxide, sulfur dioxide, and nitrogen dioxide. Two pollutants, ozone and fine particle pollution, are generally the highest, and therefore set Louisville’s AQI.

Ground-level ozone (O3) is a colorless gas that can cause or worsen coughing, irritated lungs or throat, and difficulty breathing. Ozone levels are generally higher on hot, sunny, calm, and dry days. 

Fine particle pollution (PM2.5) is a general term for a mixture of tiny solid and liquid droplets suspended in the air. When inhaled, these can cause or aggravate heart and lung issues. Sources include wood fires, industrial processes, and vehicle emissions. 
 

Resources

Enter your address and MyLouisville will find nearby city services in the following categories:

  • Garbage Icon Solid Waste Services
  • Police Badge Icon Emergency Services
  • Political Info Icon Political Info
  • House Icon General Location Info

Find your garbage, recycling, yard waste and large-item set-out dates. Sign up for large-item set out and street sweeping reminders by email and text!

The new Metro311 Reporting System and our new 311 mobile app is live!

Report Something to Us!



Call MetroCall at 311 or (502) 574-5000

No service has been selected.

No form has been selected.