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Understanding AQI Alerts: Essential Information for Your Health

June 18, 2026 · The Clime Team
Understanding AQI Alerts: Essential Information for Your Health

The Air Quality Index (AQI) is a standardized system used to communicate the quality of air in a specific area, indicating potential health risks associated with outdoor air pollution. Understanding AQI alerts is crucial for safeguarding your health, especially during periods of elevated pollution levels.

What Is the AQI?

The AQI is a numerical scale ranging from 0 to 500, where lower values represent better air quality and higher values indicate worse air quality. The scale is divided into six color-coded categories, each corresponding to a specific range of AQI values and associated health implications:

  • 0 to 50 (Green): Good air quality with little or no risk.
  • 51 to 100 (Yellow): Moderate air quality; some pollutants may pose a risk for sensitive individuals.
  • 101 to 150 (Orange): Unhealthy for Sensitive Groups; sensitive individuals may experience health effects.
  • 151 to 200 (Red): Unhealthy air quality; everyone may begin to experience health effects.
  • 201 to 300 (Purple): Very Unhealthy air quality; health alert with increased risk for everyone.
  • 301 and higher (Maroon): Hazardous air quality; emergency conditions with significant health risks.

These categories help individuals quickly assess the air quality and take appropriate actions to minimize health risks. (airnow.gov)

Common AQI Alerts and Their Implications

AQI alerts are notifications issued when air quality reaches levels that may pose health risks. These alerts are typically categorized as follows:

  • Action Days: Declared when the AQI is forecasted to reach levels categorized as Unhealthy for Sensitive Groups (Code Orange) or higher. During these days, sensitive individuals are advised to reduce prolonged or heavy exertion outdoors. (airnow.gov)

  • Health Alerts: Issued when the AQI reaches levels categorized as Unhealthy (Code Red) or higher. These alerts recommend that everyone reduce exposure to air pollution, with heightened precautions for sensitive groups. (airnow.gov)

How to Stay Informed About AQI Alerts

Staying informed about AQI levels is essential for health protection. Several resources provide real-time AQI information and alerts:

  • AirNow.gov: The U.S. Environmental Protection Agency's official website offers current AQI readings, forecasts, and health advisories for locations across the United States. (airnow.gov)

  • AirNow Mobile App: This app provides real-time AQI information, forecasts, and health recommendations, allowing users to monitor air quality on the go. (airnow.gov)

  • Local News and Weather Services: Many local news outlets and weather services report AQI levels, especially during periods of significant pollution.

Protecting Your Health During Poor Air Quality

When AQI levels are elevated, taking protective measures is crucial:

  • Limit Outdoor Activities: Reduce prolonged or heavy exertion outdoors, especially during periods of high pollution.

  • Stay Indoors: Keep windows and doors closed to minimize exposure to outdoor pollutants.

  • Use Air Purifiers: Utilize air purifiers with HEPA filters to reduce indoor air pollution.

  • Monitor Health Symptoms: Be vigilant for symptoms such as coughing, throat irritation, or shortness of breath, and seek medical attention if necessary.

Conclusion

Understanding AQI alerts and their implications is vital for maintaining health during periods of poor air quality. By staying informed and taking appropriate precautions, individuals can effectively protect themselves and their communities from the adverse effects of air pollution.

Highlights:

  • National Maps | AirNow.gov, Published on Tuesday, May 26

Frequently Asked Questions