Skip to main content

The Facts on NAAQS - National Ambient Air Quality Standards

The Environmental Protection Agency (EPA) has a statutory duty under the Clean Air Act to periodically review the National Ambient Air Quality Standards for six primary pollutants: carbon monoxide, lead, nitrogen dioxide, ozone, particle pollution and sulfur dioxide. These reviews are designed to ensure that the air quality standards are set at levels to protect public health.

A combination of cleaner gasoline and diesel fuels, modernized equipment and facilities, and more fuel efficient vehicles have helped reduce emissions of air pollutants by 62 percent between 1980 and 2013— even as vehicle miles traveled went up over 95 percent. Progress is clear —ozone concentrations under the current rules have dropped by 18 percent since 2000.

Reviews of air quality standards should be based on scientific analysis and conclusions, but too often EPA embraces an obvious politicization of the air quality standard-setting process that could mean unnecessary cost increases for consumers, job losses for workers and less energy security for America. Our national progress on air quality has been great, and we can build on this progress without going to some of the unnecessary and potentially very damaging standards EPA has proposed in the past.

Download the The Facts on NAAQs PDF document.

For detailed policy information, read our articles under the News, Policy & Issues section.


Facts on the 2023 Proposed Particulate Matter NAAQS

2023 Proposed Particulate Matter NAAQS PDF Thumbnail

Facts on the 2023 Proposed Particulate Matter NAAQS - The USEPA is taking a discretionary action to reconsider the 2020 PM NAAQS. We outline the implications of lower PM NAAQS.


The Facts on NAAQs | Graphics

Air Quality continues to improve as communities comply with existing standards, map

Air Quality Progress - EPA creates air quality trends using measurements from monitors located across the country. The table below shows that air quality based on concentrations of the common pollutants has improved nationally since 1980.


Air Quality continues to improve as communities comply with existing standards, map

Ozone Concentration - Air Quality continues to improve as communities comply with existing standards.


Projected non-attainment

Projected Non-Attainment in the United States

Thank you for Subscribing Unable to Process Request x