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Air Pollution Alerts: Be Aware

Air pollution can affect our health at any age and at any time of the year. Any one responsible for the health and safety of other people needs to be especially aware of air quality. If an air pollution alert does occur, people who supervise children, teenagers or the elderly should take immediate action to reduce any exposure to the unhealthy air.

How Are Pollution Levels Reported?

The Pollutant Standards Index (PSI) has been developed by the Environmental Protection Agency (EPA) to provide accurate, timely, and easily understandable information about daily levels of air pollution. The index provides EPA with a uniform system of measuring pollution levels for the major air pollutants in all metropolitan areas of the United States with populations exceeding 200,000. Index figures enable the public to determine whether air pollution levels in a particular location are good, moderate, unhealthful, or worse.

What Should We Do if There is an Air Pollution Alert?

Federal Health Standard

Health Advisory for Ozone: Unhealthy

Stage 1 Alert: Very Unhealthy

Stage 2 Warning: Hazardous

Stage 3 Emergency

PSI 100

PSI 150 and Above

PSI 200 and Above

PSI 300 and Above

PSI 400 and Above

People sensitive to air pollution should reduce physical exertion and limit outdoor activity.

Everyone should limit vigorous outdoor activity.

Everyone should avoid vigorous outdoor activity. Sensitive people should stay indoors.

Everyone should limit any outdoor activity. Sensitive people should stay indoors.

Everyone should stay indoors with windows and doors closed and minimize physical activity.

Next Next - What Do Scientists Say...

Impact on Health

  Our Amazing Lungs

  Who's Most at Risk?

  What Happens When We Breathe?

  The Nitty Gritty on the 6 Most Harmful Pollutants

  Air Pollution Alerts

  What the Scientists Say

Impact on Environment

Impact on Economy 

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