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New Source Review (NSR) Permitting

Learn About New Source Review

New Source Review Basics

There are three types of New Source Review (NSR) permitting requirements. A source may have to meet one or more of these permitting requirements.

  1. Prevention of Significant Deterioration (PSD) permits are required for new major sources or a major source making a major modification in areas that meet the National Ambient Air Quality Standards;

  2. Nonattainment NSR permits which are required for new major sources or major sources making a major modification in areas that do not meet one or more of the National Ambient Air Quality Standards; and

  3. Minor source permits.

What are Permits?

Permits are legal documents that facility owners and operators must follow. NSR permits specify what construction is allowed, emission limits, and often how the source must be operated.

Who Issues Permits?

Most NSR permits are issued by state or local air pollution control agencies. EPA issues permits in some cases.

EPA establishes the basic requirements for an NSR program in its federal regulations. States may develop unique NSR requirements and procedures tailored for their air quality needs as long as the program is at least as stringent as EPA's requirements. EPA must approve these programs in the State Implementation Plan (SIP).  Other states may be delegated the authority to issue permits on behalf of EPA and are often referred to as "delegated states."

To find out who issues permits where you live and what regulations apply, click on “Where Your Live” on the left side of this page, and then click on your state or territory from the map or the list below it.