Setting and Reviewing Standards to Control Particulate Matter (PM) Pollution
- What are PM air quality standards?
- How are they developed and reviewed?
- What scientific and technical information supports reviews?
National Ambient Air Quality Standards (NAAQS) for PM pollution specify a maximum amount of PM to be present in outdoor air. There are different standards for PM10 and PM2.5 (see Particulate Matter (PM) Basics to learn about particle types). Limiting PM pollution in the air protects human health and the environment.
- See NAAQS for PM for an in-depth explanation of the current PM standards, including Federal Register citations and fact sheets.
The Clean Air Act requires EPA to set national air quality standards for particulate matter, as one of the six criteria pollutants considered harmful to public health and the environment. The law also requires EPA to periodically review the standards to ensure that they provide adequate health and environmental protection, and to update those standards as necessary.
- Learn more about the standards review process
View a timeline of the particulate matter (PM) NAAQS: get an overview of how the standards have changed over time.
The various documents published during the review process include multiple drafts of plans and assessments, reports from the Clean Air Scientific Advisory Committee (CASAC), and Federal Register notices.