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Develop an Air Quality SIP

This page contains information to help air quality program managers develop State Implementation Plans (SIPs) that meet National Ambient Air Quality Standards (NAAQS).

The NAAQS are minimum federal standards for air quality to protect public health and the environment. Standards have been set for six pollutants (known as "criteria air pollutants"): sulfur dioxide (SO2), particulates (PM), ozone (O3), nitrogen oxides (NOx), carbon monoxide (CO), and lead (Pb). Learn more about criteria air pollutants.

On this page:

SIP checklists

Start here if you're developing a SIP for one of these pollutants:



  • Redesignation and Clean Data Policy (CDP) - In designated nonattainment areas where monitored data demonstrate that the NAAQS have been achieved, EPA interprets certain requirements of the Clean Air Act as no longer applicable for so long as air quality continues to meet the standard.
  • Startup, shutdown, and malfunction (SSM) emissions - Rule requiring states to have plans in place that require industrial facilities to follow air pollution rules during times when the facility is starting up or shutting down, or when a malfunction occurs.

Air quality and emissions data

  • Status and trends of key air pollutants - EPA tracks the levels of criteria air pollutants and how much of each pollutant is emitted from various pollution sources.
  • Design values - A design value is a statistic that describes the air quality status of a given location relative to the level of the NAAQS.
  • AirNow - Current air quality index.
  • Air Data - Air quality data collected at outdoor monitors across the U.S.

EPA programs that can help improve your air quality

These EPA partnership programs can help reduce air pollution to keep your airshed in attainment.

  • Advance - A collaboration between EPA, states, tribes, and local governments to encourage ozone and fine particulate (PM2.5) emission reductions.
  • Air Quality Flag Program - Alerts organizations to the local air quality forecast and helps them to take actions to protect people’s health.
  • BurnWise - A voluntary partnership program between EPA, state agencies, manufacturers, and consumers to emphasize the importance of burning the right wood, the right way, in the right appliance.