Air Quality Awareness Week: EPA Clean Air Science

By Maggie Sauerhage

Recess at last!

Impatiently, you watch the second hand tick, tick, tick around the clock. Is it possible that it’s slowing down? Finally, it hits the 12 and you hear that magical sound: RRRRING! It’s time for recess! You jump out of your seat, knocking over your chair, and run to freedom alongside your classmates. Throwing the doors open, you’re welcomed by the warm glow of sunshine and the scent of grass, flowers, and blacktop. Taking a deep breath, you fill your lungs with air before running off to join friends in a game of kickball, tag, or to see who can swing highest.

Recess was one of the best parts of my day when I was younger. I was lucky. As reported recently in The New York Times, many kids in China’s cities often have to stay indoors because of high levels of air pollution. Teachers there check the U.S. Consulate’s website or their own government’s website for an air quality reading, to make sure it’s safe for children to go outside.

While air pollution levels in the United States are significantly lower, many cities still have days when the air pollution exceeds what is considered healthy, especially for certain at-risk populations such as those already dealing with asthma or cardiovascular problems (also see EPA’s Green Heart initiative). That’s why EPA scientists are conducting air research and learning how to keep us healthy.

EPA’s National Ambient Air Quality Standards—for six principal pollutants—were developed to help protect human health and the environment. EPA scientists study how the six pollutants are formed, the ways they interact in the atmosphere, and their impacts.

The Clean Air Act requires EPA researchers to periodically review the science behind these standards to ensure the latest findings are used to inform efforts to protect human health and the einvironment. These reviews include scientific assessments of all the existing research on each pollutant.

Scientists must also closely monitor daily levels of pollutants in the air to make sure they aren’t unhealthy. They’ve developed models that are used by the National Weather Service to give daily U.S. ozone forecasts, and states use them to make sure they are complying with clean air standards.

All of this research helps EPA calculate the Air Quality Index (AQI) each day to inform the public of air quality in their neighborhood. The AQI is an easy-to-use table that’s color-coded to match levels of air pollution. The scale goes from 0-500, and the higher the value, the more harmful the level of pollution. To check your air quality forecast, all you have to do is enter your zip code. You can also download an app for your phone to check air quality on the go.

Unfortunately, I’ve outgrown recess. But air quality is still as important to me as it is to the millions of kids who depend on clean air to go outside and play with their friends. So don’t forget to check the AQI next time you want to enjoy the great outdoors!

About the Author: Maggie Sauerhage is a student services contractor working on the Science Communications Team in EPA’s Office of Research and Development.

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