One way to determine air quality is to measure how much ozone is near the ground. This ozone layer is different from the ozone layer high above the Earth, which protects living things from the ultraviolet rays of the sun. A lot of ozone near the ground indicates that air pollution is high. Scientists closely monitor ozone levels. When there is too much ozone near the ground, they declare Ozone Action Days. On these days, people are asked to do things that will help improve air quality.

To learn more about Ozone Action Days:

1. Go to the Breathe Easier WWW Sheet and print it.

2. Visit these Web sites. Then complete the WWW Sheet.
    Ozone Action Days
    What You Can Do