American Lung Association: “The “State of the Air” 2022 report finds that despite decades of progress on cleaning up sources of air pollution, more than 40% of Americans—over 137 million people—are living in places with failing grades for unhealthy levels of particle pollution or ozone. This is 2.1 million more people breathing unhealthy air compared to last year’s report. Nearly 9 million more people were impacted by daily spikes in deadly particle pollution than reported last year. In the three years covered by this report, Americans experienced more days of “very unhealthy” and “hazardous” air quality than ever before in the two-decade history of “State of the Air.”  More than 4 in 10 Americans live in places with unhealthy levels of air pollution. The “State of the Air” report looks at two of the most widespread and dangerous air pollutants, fine particles and ozone. The air quality data used in the report is collected at official monitoring sites across the United States by the federal, state, local and Tribal governments. The Lung Association calculates values reflecting the air pollution problem and assigns grades for daily and long-term measures of particle pollution and daily measures of ozone. Those values are also used to rank cities (metropolitan areas) and counties. This year’s report presents data from 2018, 2019 and 2020, the most recent quality-assured nationwide air pollution data publicly available. See About This Report for more detail about the methodology for data collection and analysis.”

See also Greater Greater Washington: “Last week, the American Lung Association gave the Washington region grades of “F” for ozone and “C” for particle pollution levels in its annual State of the Air report, reminding us of the grave price that any dependence on personal vehicles for mobility exacts on our health.//”