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What are new source performance standards (NSPS)?
Section 111 of the federal Clean Air Act directs EPA to establish pollution control requirements for certain industrial activities which emit significant "criteria air pollutants." These requirements are known as new source performance standards (NSPS) and regulate pollutants such as particulate matter, sulfur dioxide, carbon monoxide, nitrogen oxides, volatile organic compounds, acid mist, total reduced sulfur and fluorides. NSPS are detailed in Chapter 40 of the Code of Federal Regulations, Part 60 (40 CFR Part 60), and are intended primarily to establish minimum nationwide requirements for new facilities.

What are national emission standards for hazardous air pollutants (NESHAPs)?
Section 112 of the pre-1990 federal Clean Air Act directed EPA to establish standards to reduce emissions of hazardous air pollutants (HAPs). These pollutants include asbestos, benzene, beryllium, inorganic arsenic, mercury, radionuclides, and vinyl chloride. NESHAPs are detailed in 40 CFR Part 61 and establish minimum nationwide requirements for existing and new facilities.

What are maximum achievable control technology (MACT) standards?
The post-1990 NESHAPs require the maximum achievable control technology (MACT) for a particular industrial source category, and are often referred to as "MACT standards." The pre-1990 Clean Air Act prescribed a risk-based chemical-by-chemical approach. The 1990 Clean Air Act Amendments outlined a new approach with two main components. The first component involves establishing technology-based source category standards, and the second component involves addressing any significant remaining risk after the national standards are in place. The NESHAPs promulgated under the 1990 Clean Air Act Amendments can be found in 40 CFR Part 63 and establish nationwide requirements for existing and new facilities.

What is delegation?
After individual NSPS and NESHAPs are promulgated, EPA may implement and enforce the requirements. State and local regulatory agencies often implement and enforce similar requirements by adopting analogous regulations under state or local authority. In addition, Clean Air Act sections 111 and 112 allow EPA to transfer primary implementation and enforcement authority for most of the federal standards to state, local, or tribal regulatory agencies. This transfer of authority is called delegation. Upon delegation of a standard, sources must send any required notifications or reports directly to the delegated agency. The delegated agency may also receive authority to make certain source-specific decisions that reflect flexibility allowed by the standard.

What authorities does an agency receive with delegation?
The delegated agency becomes the primary implementation and enforcement authority for the delegated standard. In addition, the NSPS and NESHAPs programs provide some flexibility from the promulgated requirements in a number of ways, as specified in individual rules, General Provisions regulations, and the statute itself. Examples of authorities that may be delegated to state, local, or tribal agencies include the ability to issue or approve certain applicability determinations, compliance schedule extensions, or alternatives to testing or monitoring requirements. The level of EPA review for this flexibility is reflected in EPA's delegations of authority. The method for application and approval of this flexibility varies as specified in guidance or regulations.

How does delegation occur?
In general, a state, local, or tribal agency must demonstrate adequate legal authorities and resources to receive delegation of federal standards. EPA Region 9 typically delegates NSPS and NESHAPs to state, local, or tribal agencies by letter. The delegation action is subsequently announced in the Federal Register and codified into 40 CFR 60.4(b), 61.04(b), or 63.99, as appropriate. Letters of delegation are posted if available in digital format.

What authorities are not delegated?
In general, EPA does not delegate to state or local agencies the authority to make decisions that are likely to be nationally significant, or alter the stringency of the underlying standard. See
Specific Authorities Retained by EPA.

Note: The EPA has attempted to ensure that the delegations information presented on this web site accurately reflects the actions published in the Federal Register. If there are discrepancies, however, the Federal Register is the official record.

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