What 'AQI' means and why you should pay attention to it (video)

This estimate of air pollution levels can help you control health risks

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The Air Quality Index — or AQI — is an estimate of air pollution levels, including particles and ozone. The higher those levels, the greater the health risks.

The AQI in our region has varied quite a bit due to the fires throughout Northern California. In some areas, it has been hazardous for short times. UC Davis Health pulmonary experts recommend checking the AQI for your area each day. You can sign up for regular alerts for the air quality near you at sparetheair.com.

Think of the colors as a yardstick for health risks

The AQI can help you control air pollution related health risks.

The AQI is divided into levels to help people know when safety precautions are necessary. Few health effects are expected in the green (good) or yellow (moderate) zones. When the AQI reaches 101 (orange), the air is unhealthy for sensitive groups, including those with respiratory or heart disease, the elderly and children. At 151 (red) or higher, the air is unhealthy for everyone, even those with no prior health concerns. The likelihood of health problems is higher in the very unhealthy (purple) zone. Beyond that (the maroon or emergency zone) is when air quality conditions are the worst and the highest precautions are essential.

What to do when the AQI affects you 

  • Stay inside.
  • Recirculate the air in your home's central heating/cooling system (shut off the fresh-air intake) and make sure the filter has been recently changed.
  • Close all windows and doors.
  • Avoid exertion and only exercise indoors.
  • If you must go outside, only do so if you have no prior health concerns and the AQI is no higher than the red zone. Limit outdoor time to 30 to 45 minutes. Also wear an N95 or P100 mask and make sure it fits very close to the face for best filtration.

Those with chronic health conditions should closely watch their symptoms. Those with lung disease like asthma and COPD should especially monitor shortness of breath. Call your doctor if symptoms worsen. If they do get worse and don’t respond to your usual medication, don't delay in seeking urgent or emergency care.