|Air quality standards
Air quality standards tell us when there's too much pollution in the air. Standards are set for specific pollutants such as ozone,
carbon monoxide, and particulate matter. Both the U.S. Environmental Protection Agency and the ARB set standards.
These standards are based on what researchers have discovered about the effects of air pollution on human health.
Standards are set at levels that protect the people that pollution could hurt the most, such as children or adults
who exercise a lot or play sports.
A standard includes how much and how long. For example, the California standard for ozone is 9 parts
per hundred million for one hour. That's not much, but researchers have found that higher levels of ozone can harm
Here's how we measure air pollution levels around California.