---
kind: "range"
citation: "40 C.F.R. §§ 63.1–63.5"
title: "40"
from: "63.1"
to: "63.5"
count: 5
url: "https://uscodex.org/cfr/40/63.1..63.5"
---

# §63.1. Applicability.

- (a) **General.**
  - (1) Terms used throughout this part are defined in [§ 63.2](/cfr/40/63.2.md) or in the Clean Air Act (Act) as amended in 1990, except that individual subparts of this part may include specific definitions in addition to or that supersede definitions in [§ 63.2](/cfr/40/63.2.md).
  - (2) This part contains national emission standards for hazardous air pollutants (NESHAP) established pursuant to section 112 of the Act as amended November 15, 1990. These standards regulate specific categories of stationary sources that emit (or have the potential to emit) one or more hazardous air pollutants listed in this part pursuant to [section 112(b)](/cfr/40/112.md?p=b) of the Act. This section explains the applicability of such standards to sources affected by them. The standards in this part are independent of NESHAP contained in [40 CFR part 61](/cfr/40/part61.md). The NESHAP in [part 61](/cfr/40/part61.md) promulgated by signature of the Administrator before November 15, 1990 (i.e., the date of enactment of the Clean Air Act Amendments of 1990) remain in effect until they are amended, if appropriate, and added to this part.
  - (3) No emission standard or other requirement established under this part shall be interpreted, construed, or applied to diminish or replace the requirements of a more stringent emission limitation or other applicable requirement established by the Administrator pursuant to other authority of the Act ([section 111](/cfr/40/111.md), part C or D or any other authority of this Act), or a standard issued under State authority. The Administrator may specify in a specific standard under this part that facilities subject to other provisions under the Act need only comply with the provisions of that standard.
  - (4)
    - (i) Each relevant standard in this part 63 must identify explicitly whether each provision in this subpart A is or is not included in such relevant standard.
    - (ii) If a relevant [part 63](/cfr/40/part63.md) standard incorporates the requirements of [40 CFR part 60](/cfr/40/part60.md), [part 61](/cfr/40/part61.md) or other [part 63](/cfr/40/part63.md) standards, the relevant [part 63](/cfr/40/part63.md) standard must identify explicitly the applicability of each corresponding [part 60](/cfr/40/part60.md), [part 61](/cfr/40/part61.md), or other [part 63](/cfr/40/part63.md) [subpart A](/cfr/40/subpartA.md) (General) provision.
    - (iii) The General Provisions in this subpart A do not apply to regulations developed pursuant to [section 112(r)](/cfr/40/112.md?p=r) of the amended Act, unless otherwise specified in those regulations.
  - (5) [Reserved]
  - (6) To obtain the most current list of categories of sources to be regulated under section 112 of the Act, or to obtain the most recent regulation promulgation schedule established pursuant to section 112(e) of the Act, contact the Office of the Director, Emission Standards Division, Office of Air Quality Planning and Standards, U.S. EPA (MD-13), Research Triangle Park, North Carolina 27711.
  - (7) -(9) [Reserved]
  - (10) For the purposes of this part, time periods specified in days shall be measured in calendar days, even if the word “calendar” is absent, unless otherwise specified in an applicable requirement.
  - (11) For the purposes of this part, if an explicit postmark deadline is not specified in an applicable requirement for the submittal of a notification, application, test plan, report, or other written communication to the Administrator, the owner or operator shall postmark the submittal on or before the number of days specified in the applicable requirement. For example, if a notification must be submitted 15 days before a particular event is scheduled to take place, the notification shall be postmarked on or before 15 days preceding the event; likewise, if a notification must be submitted 15 days after a particular event takes place, the notification shall be postmarked on or before 15 days following the end of the event. The use of reliable non-Government mail carriers that provide indications of verifiable delivery of information required to be submitted to the Administrator, similar to the postmark provided by the U.S. Postal Service, or alternative means of delivery agreed to by the permitting authority, is acceptable.
  - (12) Notwithstanding time periods or postmark deadlines specified in this part for the submittal of information to the Administrator by an owner or operator, or the review of such information by the Administrator, such time periods or deadlines may be changed by mutual agreement between the owner or operator and the Administrator. Procedures governing the implementation of this provision are specified in [§ 63.9(i)](/cfr/40/63.9.md?p=i).
- (b) **Initial applicability determination for this part.**
  - (1) **The provisions of this part apply to the owner or operator of any stationary source that—**
    - (i) Emits or has the potential to emit any hazardous air pollutant listed in or pursuant to section 112(b) of the Act; and
    - (ii) Is subject to any standard, limitation, prohibition, or other federally enforceable requirement established pursuant to this part.
  - (2) [Reserved]
  - (3) An owner or operator of a stationary source who is in the relevant source category and who determines that the source is not subject to a relevant standard or other requirement established under this part must keep a record as specified in [§ 63.10(b)(3)](/cfr/40/63.10.md?p=b-3).
- (c) **Applicability of this part after a relevant standard has been set under this part.**
  - (1) If a relevant standard has been established under this part, the owner or operator of an affected source must comply with the provisions of that standard and of this subpart as provided in [paragraph (a)(4)](#a-4) of this section.
  - (2) Except as provided in [§ 63.10(b)(3)](/cfr/40/63.10.md?p=b-3), if a relevant standard has been established under this part, the owner or operator of an affected source may be required to obtain a title V permit from a permitting authority in the State in which the source is located. Emission standards promulgated in this part for area sources pursuant to section 112(c)(3) of the Act will specify whether—
    - (i) States will have the option to exclude area sources affected by that standard from the requirement to obtain a title V permit (i.e., the standard will exempt the category of area sources altogether from the permitting requirement);
    - (ii) States will have the option to defer permitting of area sources in that category until the Administrator takes rulemaking action to determine applicability of the permitting requirements; or
    - (iii) If a standard fails to specify what the permitting requirements will be for area sources affected by such a standard, then area sources that are subject to the standard will be subject to the requirement to obtain a title V permit without any deferral.
  - (3) -(4) [Reserved]
  - (5) If an area source that otherwise would be subject to an emission standard or other requirement established under this part if it were a major source subsequently increases its emissions of hazardous air pollutants (or its potential to emit hazardous air pollutants) such that the source is a major source that is subject to the emission standard or other requirement, such source also shall be subject to the notification requirements of this subpart.
  - (6) A major source may become an area source at any time upon reducing its emissions of and potential to emit hazardous air pollutants, as defined in this subpart, to below the major source thresholds established in [§ 63.2](/cfr/40/63.2.md), subject to the provisions in paragraphs [(c)(6)(i)](#c-6-i) and [(ii)](#c-6-ii) of this section.
    - (i) A major source reclassifying to area source status is subject to the applicability of standards, compliance dates and notification requirements specified in (c)(6)(i)(A) of this section. An area source that previously was a major source and becomes a major source again is subject to the applicability of standards, compliance dates, and notification requirements specified in (c)(6)(i)(B) of this section:
      - (A) A major source reclassifying to area source status under this part remains subject to any applicable major source requirements established under this part until the reclassification becomes effective. After the reclassification becomes effective, the source is subject to any applicable area source requirements established under this part immediately, provided the compliance date for the area source requirements has passed. The owner or operator of a major source that becomes an area source subject to newly applicable area source requirements under this part must comply with the initial notification requirements pursuant to [§ 63.9(b)](/cfr/40/63.9.md?p=b). The owner or operator of a major source that becomes an area source must also provide to the Administrator any change in the information already provided under [§ 63.9(b)](/cfr/40/63.9.md?p=b) per [§ 63.9(j)](/cfr/40/63.9.md?p=j).
      - (B) An area source that previously was a major source under this part and that becomes a major source again is subject to the applicable major source requirements established under this part immediately upon becoming a major source again, provided the compliance date for the major source requirements has passed, notwithstanding any provision within the applicable [subparts. The](/cfr/40/subpartThe.md) owner or operator of an area source that becomes a major source again must comply with the initial notification pursuant to [§ 63.9(b)](/cfr/40/63.9.md?p=b). The owner or operator must also provide to the Administrator any change in the information already provided under [§ 63.9(b)](/cfr/40/63.9.md?p=b) per [§ 63.9(j)](/cfr/40/63.9.md?p=j).
    - (ii) Becoming an area source does not absolve a source subject to an enforcement action or investigation for major source violations or infractions from the consequences of any actions occurring when the source was major. Becoming a major source does not absolve a source subject to an enforcement action or investigation for area source violations or infractions from the consequences of any actions occurring when the source was an area source.
- (d) [Reserved]
- (e) If the Administrator promulgates an emission standard under section 112(d) or (h) of the Act that is applicable to a source subject to an emission limitation by permit established under section 112(j) of the Act, and the requirements under the [section 112(j)](/cfr/40/112.md?p=j) emission limitation are substantially as effective as the promulgated emission standard, the owner or operator may request the permitting authority to revise the source's title V permit to reflect that the emission limitation in the permit satisfies the requirements of the promulgated emission standard. The process by which the permitting authority determines whether the [section 112(j)](/cfr/40/112.md?p=j) emission limitation is substantially as effective as the promulgated emission standard must include, consistent with part [70](/cfr/40/part70.md) or [71](/cfr/40/part71.md) of this chapter, the opportunity for full public, EPA, and affected State review (including the opportunity for EPA's objection) prior to the permit revision being finalized. A negative determination by the permitting authority constitutes final action for purposes of review and appeal under the applicable title V operating permit program.

# §63.2. Definitions.


The terms used in this part are defined in the Act or in this section as follows:

Act means the Clean Air Act ([42 U.S.C. 7401](/usc/42/7401.md) et seq., as amended by Pub. L. 101-549, 104 Stat. 2399).

Actual emissions is defined in subpart D of this part for the purpose of granting a compliance extension for an early reduction of hazardous air pollutants.

Administrator means the Administrator of the United States Environmental Protection Agency or his or her authorized representative (e.g., a State that has been delegated the authority to implement the provisions of this part).

Affected source, for the purposes of this part, means the collection of equipment, activities, or both within a single contiguous area and under common control that is included in a [section 112(c)](/cfr/40/112.md?p=c) source category or subcategory for which a [section 112(d)](/cfr/40/112.md?p=d) standard or other relevant standard is established pursuant to [section 112](/cfr/40/112.md) of the Act. Each relevant standard will define the “affected source,” as defined in this paragraph unless a different definition is warranted based on a published justification as to why this definition would result in significant administrative, practical, or implementation problems and why the different definition would resolve those problems. The term “affected source,” as used in this part, is separate and distinct from any other use of that term in EPA regulations such as those implementing title IV of the Act. Affected source may be defined differently for [part 63](/cfr/40/part63.md) than affected facility and stationary source in parts [60](/cfr/40/part60.md) and [61](/cfr/40/part61.md), respectively. This definition of “affected source,” and the procedures for adopting an alternative definition of “affected source,” shall apply to each [section 112(d)](/cfr/40/112.md?p=d) standard for which the initial proposed rule is signed by the Administrator after June 30, 2002.

Alternative emission limitation means conditions established pursuant to sections 112(i)(5) or 112(i)(6) of the Act by the Administrator or by a State with an approved permit program.

Alternative emission standard means an alternative means of emission limitation that, after notice and opportunity for public comment, has been demonstrated by an owner or operator to the Administrator's satisfaction to achieve a reduction in emissions of any air pollutant at least equivalent to the reduction in emissions of such pollutant achieved under a relevant design, equipment, work practice, or operational emission standard, or combination thereof, established under this part pursuant to [section 112(h)](/cfr/40/112.md?p=h) of the Act.

Alternative test method means any method of sampling and analyzing for an air pollutant that has been demonstrated to the Administrator's satisfaction, using Method 301 in appendix A of this part, to produce results adequate for the Administrator's determination that it may be used in place of a test method specified in this part.

Approved permit program means a State permit program approved by the Administrator as meeting the requirements of [part 70](/cfr/40/part70.md) of this chapter or a Federal permit program established in this chapter pursuant to title V of the Act ([42 U.S.C. 7661](/usc/42/7661.md)).

Area source means any stationary source of hazardous air pollutants that is not a major source as defined in this part.

Commenced means, with respect to construction or reconstruction of an affected source, that an owner or operator has undertaken a continuous program of construction or reconstruction or that an owner or operator has entered into a contractual obligation to undertake and complete, within a reasonable time, a continuous program of construction or reconstruction.

Compliance date means the date by which an affected source is required to be in compliance with a relevant standard, limitation, prohibition, or any federally enforceable requirement established by the Administrator (or a State with an approved permit program) pursuant to [section 112](/cfr/40/112.md) of the Act.

Compliance schedule means: (1) In the case of an affected source that is in compliance with all applicable requirements established under this part, a statement that the source will continue to comply with such requirements; or

- (2) In the case of an affected source that is required to comply with applicable requirements by a future date, a statement that the source will meet such requirements on a timely basis and, if required by an applicable requirement, a detailed schedule of the dates by which each step toward compliance will be reached; or
- (3) In the case of an affected source not in compliance with all applicable requirements established under this part, a schedule of remedial measures, including an enforceable sequence of actions or operations with milestones and a schedule for the submission of certified progress reports, where applicable, leading to compliance with a relevant standard, limitation, prohibition, or any federally enforceable requirement established pursuant to section 112 of the Act for which the affected source is not in compliance. This compliance schedule shall resemble and be at least as stringent as that contained in any judicial consent decree or administrative order to which the source is subject. Any such schedule of compliance shall be supplemental to, and shall not sanction noncompliance with, the applicable requirements on which it is based.

  Construction means the on-site fabrication, erection, or installation of an affected source. Construction does not include the removal of all equipment comprising an affected source from an existing location and reinstallation of such equipment at a new location. The owner or operator of an existing affected source that is relocated may elect not to reinstall minor ancillary equipment including, but not limited to, piping, ductwork, and valves. However, removal and reinstallation of an affected source will be construed as reconstruction if it satisfies the criteria for reconstruction as defined in this section. The costs of replacing minor ancillary equipment must be considered in determining whether the existing affected source is reconstructed.

  Continuous emission monitoring system (CEMS) means the total equipment that may be required to meet the data acquisition and availability requirements of this part, used to sample, condition (if applicable), analyze, and provide a record of emissions.

  Continuous monitoring system (CMS) is a comprehensive term that may include, but is not limited to, continuous emission monitoring systems, continuous opacity monitoring systems, continuous parameter monitoring systems, or other manual or automatic monitoring that is used for demonstrating compliance with an applicable regulation on a continuous basis as defined by the regulation.

  Continuous opacity monitoring system (COMS) means a continuous monitoring system that measures the opacity of emissions.

  Continuous parameter monitoring system means the total equipment that may be required to meet the data acquisition and availability requirements of this part, used to sample, condition (if applicable), analyze, and provide a record of process or control system parameters.

  Effective date means:

- (1) With regard to an emission standard established under this part, the date of promulgation in the Federal Register of such standard; or
- (2) With regard to an alternative emission limitation or equivalent emission limitation determined by the Administrator (or a State with an approved permit program), the date that the alternative emission limitation or equivalent emission limitation becomes effective according to the provisions of this part.

  Emission standard means a national standard, limitation, prohibition, or other regulation promulgated in a subpart of this part pursuant to sections [112(d)](/cfr/40/112.md?p=d), [112(h)](/cfr/40/112.md?p=h), or [112(f)](/cfr/40/112.md?p=f) of the Act.

  Emissions averaging is a way to comply with the emission limitations specified in a relevant standard, whereby an affected source, if allowed under a subpart of this part, may create emission credits by reducing emissions from specific points to a level below that required by the relevant standard, and those credits are used to offset emissions from points that are not controlled to the level required by the relevant standard.

  EPA means the United States Environmental Protection Agency.

  Equivalent emission limitation means any maximum achievable control technology emission limitation or requirements which are applicable to a major source of hazardous air pollutants and are adopted by the Administrator (or a State with an approved permit program) on a case-by-case basis, pursuant to section [112(g)](/cfr/40/112.md?p=g) or [(j)](/cfr/40/112.md?p=j) of the Act.

  Excess emissions and continuous monitoring system performance report is a report that must be submitted periodically by an affected source in order to provide data on its compliance with relevant emission limits, operating parameters, and the performance of its continuous parameter monitoring systems.

  Existing source means any affected source that is not a new source.

  Federally enforceable means all limitations and conditions that are enforceable by the Administrator and citizens under the Act or that are enforceable under other statutes administered by the Administrator. Examples of federally enforceable limitations and conditions include, but are not limited to:

- (1) Emission standards, alternative emission standards, alternative emission limitations, and equivalent emission limitations established pursuant to section 112 of the Act as amended in 1990;
- (2) New source performance standards established pursuant to section 111 of the Act, and emission standards established pursuant to section 112 of the Act before it was amended in 1990;
- (3) All terms and conditions in a title V permit, including any provisions that limit a source's potential to emit, unless expressly designated as not federally enforceable;
- (4) Limitations and conditions that are part of an approved State Implementation Plan (SIP) or a Federal Implementation Plan (FIP);
- (5) Limitations and conditions that are part of a Federal construction permit issued under [40 CFR 52.21](/cfr/40/52.21.md) or any construction permit issued under regulations approved by the EPA in accordance with [40 CFR part 51](/cfr/40/part51.md);
- (6) Limitations and conditions that are part of an operating permit where the permit and the permitting program pursuant to which it was issued meet all of the following criteria:
  - (i) The operating permit program has been submitted to and approved by EPA into a State implementation plan (SIP) under [section 110](/cfr/40/110.md) of the CAA;
  - (ii) The SIP imposes a legal obligation that operating permit holders adhere to the terms and limitations of such permits and provides that permits which do not conform to the operating permit program requirements and the requirements of EPA's underlying regulations may be deemed not “federally enforceable” by EPA;
  - (iii) The operating permit program requires that all emission limitations, controls, and other requirements imposed by such permits will be at least as stringent as any other applicable limitations and requirements contained in the SIP or enforceable under the SIP, and that the program may not issue permits that waive, or make less stringent, any limitations or requirements contained in or issued pursuant to the SIP, or that are otherwise “federally enforceable”;
  - (iv) The limitations, controls, and requirements in the permit in question are permanent, quantifiable, and otherwise enforceable as a practical matter; and
  - (v) The permit in question was issued only after adequate and timely notice and opportunity for comment for EPA and the public.
- (7) Limitations and conditions in a State rule or program that has been approved by the EPA under [subpart E](/cfr/40/subpartE.md) of this part for the purposes of implementing and enforcing [section 112](/cfr/40/112.md); and
- (8) **Individual consent agreements that the EPA has legal authority to create.** Fixed capital cost means the capital needed to provide all the depreciable components of an existing source.

  Force majeure means, for purposes of [§ 63.7](/cfr/40/63.7.md), an event that will be or has been caused by circumstances beyond the control of the affected facility, its contractors, or any entity controlled by the affected facility that prevents the owner or operator from complying with the regulatory requirement to conduct performance tests within the specified timeframe despite the affected facility's best efforts to fulfill the obligation. Examples of such events are acts of nature, acts of war or terrorism, or equipment failure or safety hazard beyond the control of the affected facility.

  Fugitive emissions means those emissions from a stationary source that could not reasonably pass through a stack, chimney, vent, or other functionally equivalent opening. Under section 112 of the Act, all fugitive emissions are to be considered in determining whether a stationary source is a major source.

  Hazardous air pollutant means any air pollutant listed in or pursuant to [section 112(b)](/cfr/40/112.md?p=b) of the Act.

  Issuance of a [part 70](/cfr/40/part70.md) permit will occur, if the State is the permitting authority, in accordance with the requirements of [part 70](/cfr/40/part70.md) of this chapter and the applicable, approved State permit program. When the EPA is the permitting authority, issuance of a title V permit occurs immediately after the EPA takes final action on the final permit.

  Major source means any stationary source or group of stationary sources located within a contiguous area and under common control that emits or has the potential to emit considering controls, in the aggregate, 10 tons per year or more of any hazardous air pollutant or 25 tons per year or more of any combination of hazardous air pollutants, unless the Administrator establishes a lesser quantity, or in the case of radionuclides, different criteria from those specified in this sentence.

  Malfunction means any sudden, infrequent, and not reasonably preventable failure of air pollution control and monitoring equipment, process equipment, or a process to operate in a normal or usual manner which causes, or has the potential to cause, the emission limitations in an applicable standard to be exceeded. Failures that are caused in part by poor maintenance or careless operation are not malfunctions.

  Monitoring means the collection and use of measurement data or other information to control the operation of a process or pollution control device or to verify a work practice standard relative to assuring compliance with applicable requirements. Monitoring is composed of four elements:

- (1) **Indicator(s) of performance—** the parameter or parameters you measure or observe for demonstrating proper operation of the pollution control measures or compliance with the applicable emissions limitation or standard. Indicators of performance may include direct or predicted emissions measurements (including opacity), operational parametric values that correspond to process or control device (and capture system) efficiencies or emissions rates, and recorded findings of inspection of work practice activities, materials tracking, or design characteristics. Indicators may be expressed as a single maximum or minimum value, a function of process variables (for example, within a range of pressure drops), a particular operational or work practice status (for example, a damper position, completion of a waste recovery task, materials tracking), or an interdependency between two or among more than two variables.
- (2) **Measurement techniques—** the means by which you gather and record information of or about the indicators of performance. The components of the measurement technique include the detector type, location and installation specifications, inspection procedures, and quality assurance and quality control measures. Examples of measurement techniques include continuous emission monitoring systems, continuous opacity monitoring systems, continuous parametric monitoring systems, and manual inspections that include making records of process conditions or work practices.
- (3) **Monitoring frequency—** the number of times you obtain and record monitoring data over a specified time interval. Examples of monitoring frequencies include at least four points equally spaced for each hour for continuous emissions or parametric monitoring systems, at least every 10 seconds for continuous opacity monitoring systems, and at least once per operating day (or week, month, etc.) for work practice or design inspections.
- (4) **Averaging time—** the period over which you average and use data to verify proper operation of the pollution control approach or compliance with the emissions limitation or standard. Examples of averaging time include a 3-hour average in units of the emissions limitation, a 30-day rolling average emissions value, a daily average of a control device operational parametric range, and an instantaneous alarm.

  New affected source means the collection of equipment, activities, or both within a single contiguous area and under common control that is included in a [section 112(c)](/cfr/40/112.md?p=c) source category or subcategory that is subject to a [section 112(d)](/cfr/40/112.md?p=d) or other relevant standard for new sources. This definition of “new affected source,” and the criteria to be utilized in implementing it, shall apply to each [section 112(d)](/cfr/40/112.md?p=d) standard for which the initial proposed rule is signed by the Administrator after June 30, 2002. Each relevant standard will define the term “new affected source,” which will be the same as the “affected source” unless a different collection is warranted based on consideration of factors including:

- (1) Emission reduction impacts of controlling individual sources versus groups of sources;
- (2) Cost effectiveness of controlling individual equipment;
- (3) Flexibility to accommodate common control strategies;
- (4) Cost/benefits of emissions averaging;
- (5) Incentives for pollution prevention;
- (6) Feasibility and cost of controlling processes that share common equipment (e.g., product recovery devices);
- (7) Feasibility and cost of monitoring; and
- (8) **Other relevant factors.** New source means any affected source the construction or reconstruction of which is commenced after the Administrator first proposes a relevant emission standard under this part establishing an emission standard applicable to such source.

  One-hour period, unless otherwise defined in an applicable subpart, means any 60-minute period commencing on the hour.

  Opacity means the degree to which emissions reduce the transmission of light and obscure the view of an object in the background. For continuous opacity monitoring systems, opacity means the fraction of incident light that is attenuated by an optical medium.

  Owner or operator means any person who owns, leases, operates, controls, or supervises a stationary source.

  Performance audit means a procedure to analyze blind samples, the content of which is known by the Administrator, simultaneously with the analysis of performance test samples in order to provide a measure of test data quality.

  Performance evaluation means the conduct of relative accuracy testing, calibration error testing, and other measurements used in validating the continuous monitoring system data.

  Performance test means the collection of data resulting from the execution of a test method (usually three emission test runs) used to demonstrate compliance with a relevant emission standard as specified in the performance test section of the relevant standard.

  Permit modification means a change to a title V permit as defined in regulations codified in this chapter to implement title V of the Act ([42 U.S.C. 7661](/usc/42/7661.md)).

  Permit program means a comprehensive State operating permit system established pursuant to title V of the Act ([42 U.S.C. 7661](/usc/42/7661.md)) and regulations codified in [part 70](/cfr/40/part70.md) of this chapter and applicable State regulations, or a comprehensive Federal operating permit system established pursuant to title V of the Act and regulations codified in this chapter.

  Permit revision means any permit modification or administrative permit amendment to a title V permit as defined in regulations codified in this chapter to implement title V of the Act ([42 U.S.C. 7661](/usc/42/7661.md)).

  Permitting authority means: (1) The State air pollution control agency, local agency, other State agency, or other agency authorized by the Administrator to carry out a permit program under [part 70](/cfr/40/part70.md) of this chapter; or

- (2) The Administrator, in the case of EPA-implemented permit programs under title V of the Act ([42 U.S.C. 7661](/usc/42/7661.md)).

  Pollution Prevention means source reduction as defined under the Pollution Prevention Act ([42 U.S.C. 13101-13109](/usc/42/13101-13109.md)). The definition is as follows:

- (1) **Source reduction—** is any practice that:
  - (i) Reduces the amount of any hazardous substance, pollutant, or contaminant entering any waste stream or otherwise released into the environment (including fugitive emissions) prior to recycling, treatment, or disposal; and
  - (ii) Reduces the hazards to public health and the environment associated with the release of such substances, pollutants, or contaminants.
- (2) The term source reduction includes equipment or technology modifications, process or procedure modifications, reformulation or redesign of products, substitution of raw materials, and improvements in housekeeping, maintenance, training, or inventory control.
- (3) The term source reduction does not include any practice that alters the physical, chemical, or biological characteristics or the volume of a hazardous substance, pollutant, or contaminant through a process or activity which itself is not integral to and necessary for the production of a product or the providing of a service.

  Potential to emit means the maximum capacity of a stationary source to emit a pollutant under its physical and operational design. Any physical or operational limitation on the capacity of the stationary source to emit a pollutant, including air pollution control equipment and restrictions on hours of operation or on the type or amount of material combusted, stored, or processed, shall be treated as part of its design if the limitation or the effect it would have on emissions is enforceable.

  Reconstruction, unless otherwise defined in a relevant standard, means the replacement of components of an affected or a previously nonaffected source to such an extent that:

- (1) The fixed capital cost of the new components exceeds 50 percent of the fixed capital cost that would be required to construct a comparable new source; and
- (2) It is technologically and economically feasible for the reconstructed source to meet the relevant standard(s) established by the Administrator (or a State) pursuant to [section 112](/cfr/40/112.md) of the Act. Upon reconstruction, an affected source, or a stationary source that becomes an affected source, is subject to relevant standards for new sources, including compliance dates, irrespective of any change in emissions of hazardous air pollutants from that source.

  Regulation promulgation schedule means the schedule for the promulgation of emission standards under this part, established by the Administrator pursuant to section 112(e) of the Act and published in the Federal Register.

  Relevant standard means:

- (1) An emission standard;
- (2) An alternative emission standard;
- (3) An alternative emission limitation; or
- (4) An equivalent emission limitation established pursuant to section 112 of the Act that applies to the collection of equipment, activities, or both regulated by such standard or limitation. A relevant standard may include or consist of a design, equipment, work practice, or operational requirement, or other measure, process, method, system, or technique (including prohibition of emissions) that the Administrator (or a State) establishes for new or existing sources to which such standard or limitation applies. Every relevant standard established pursuant to section 112 of the Act includes [subpart A](/cfr/40/subpartA.md) of this part, as provided by [§ 63.1(a)(4)](/cfr/40/63.1.md?p=a-4), and all applicable appendices of this part or of other parts of this chapter that are referenced in that standard.

  Responsible official means one of the following:

- (1) **For a corporation—** A president, secretary, treasurer, or vice president of the corporation in charge of a principal business function, or any other person who performs similar policy or decision-making functions for the corporation, or a duly authorized representative of such person if the representative is responsible for the overall operation of one or more manufacturing, production, or operating facilities and either:
  - (i) The facilities employ more than 250 persons or have gross annual sales or expenditures exceeding $25 million (in second quarter 1980 dollars); or
  - (ii) **The delegation of authority to such representative is approved in advance by the Administrator.**
- (2) **For a partnership or sole proprietorship—** a general partner or the proprietor, respectively.
- (3) **For a municipality, State, Federal, or other public agency—** either a principal executive officer or ranking elected official. For the purposes of this part, a principal executive officer of a Federal agency includes the chief executive officer having responsibility for the overall operations of a principal geographic unit of the agency (e.g., a Regional Administrator of the EPA).
- (4) **For affected sources (as defined in this part) applying for or subject to a title V permit—** “responsible official” shall have the same meaning as defined in [part 70](/cfr/40/part70.md) or Federal title V regulations in this chapter ([42 U.S.C. 7661](/usc/42/7661.md)), whichever is applicable.

  Run means one of a series of emission or other measurements needed to determine emissions for a representative operating period or cycle as specified in this part.

  Shutdown means the cessation of operation of an affected source or portion of an affected source for any purpose.

  Six-minute period means, with respect to opacity determinations, any one of the 10 equal parts of a 1-hour period.

  Source at a Performance Track member facility means a major or area source located at a facility which has been accepted by EPA for membership in the Performance Track Program (as described at www.epa.gov/PerformanceTrack) and is still a member of the Program. The Performance Track Program is a voluntary program that encourages continuous environmental improvement through the use of environmental management systems, local community outreach, and measurable results.

  Standard conditions means a temperature of 293 K (68 °F) and a pressure of 101.3 kilopascals (29.92 in. Hg).

  Startup means the setting in operation of an affected source or portion of an affected source for any purpose.

  State means all non-Federal authorities, including local agencies, interstate associations, and State-wide programs, that have delegated authority to implement: (1) The provisions of this part and/or (2) the permit program established under [part 70](/cfr/40/part70.md) of this chapter. The term State shall have its conventional meaning where clear from the context.

  Stationary source means any building, structure, facility, or installation which emits or may emit any air pollutant.

  Test method means the validated procedure for sampling, preparing, and analyzing for an air pollutant specified in a relevant standard as the performance test procedure. The test method may include methods described in an appendix of this chapter, test methods incorporated by reference in this part, or methods validated for an application through procedures in Method 301 of appendix A of this part.

  Title V permit means any permit issued, renewed, or revised pursuant to Federal or State regulations established to implement title V of the Act ([42 U.S.C. 7661](/usc/42/7661.md)). A title V permit issued by a State permitting authority is called a [part 70](/cfr/40/part70.md) permit in this part.

  Visible emission means the observation of an emission of opacity or optical density above the threshold of vision.

  Working day means any day on which Federal Government offices (or State government offices for a State that has obtained delegation under [section 112(l)](/cfr/40/112.md?p=l)) are open for normal business. Saturdays, Sundays, and official Federal (or where delegated, State) holidays are not working days.


# §63.3. Units and abbreviations.


Used in this part are abbreviations and symbols of units of measure. These are defined as follows:

- (a) **System International (SI) units of measure—**
- (b) **Other units of measure—**
- (c) **Miscellaneous—**

# §63.4. Prohibited activities and circumvention.

- (a) **Prohibited activities.**
  - (1) No owner or operator subject to the provisions of this part must operate any affected source in violation of the requirements of this part. Affected sources subject to and in compliance with either an extension of compliance or an exemption from compliance are not in violation of the requirements of this part. An extension of compliance can be granted by the Administrator under this part; by a State with an approved permit program; or by the President under [section 112(i)(4)](/cfr/40/112.md?p=i-4) of the Act.
  - (2) No owner or operator subject to the provisions of this part shall fail to keep records, notify, report, or revise reports as required under this part.
  - (3) -(5) [Reserved]
- (b) **Circumvention.** No owner or operator subject to the provisions of this part shall build, erect, install, or use any article, machine, equipment, or process to conceal an emission that would otherwise constitute noncompliance with a relevant standard. Such concealment includes, but is not limited to—
  - (1) The use of diluents to achieve compliance with a relevant standard based on the concentration of a pollutant in the effluent discharged to the atmosphere;
  - (2) The use of gaseous diluents to achieve compliance with a relevant standard for visible emissions; and
- (c) **Fragmentation.** Fragmentation after November 15, 1990 which divides ownership of an operation, within the same facility among various owners where there is no real change in control, will not affect applicability. The owner and operator must not use fragmentation or phasing of reconstruction activities (i.e., intentionally dividing reconstruction into multiple parts for purposes of avoiding new source requirements) to avoid becoming subject to new source requirements.

# §63.5. Preconstruction review and notification requirements.

- (a) **Applicability.**
  - (1) **This section implements the preconstruction review requirements of section 112(i)(1).** After the effective date of a relevant standard, promulgated pursuant to section 112(d), (f), or (h) of the Act, under this part, the preconstruction review requirements in this section apply to the owner or operator of new affected sources and reconstructed affected sources that are major-emitting as specified in this section. New and reconstructed affected sources that commence construction or reconstruction before the effective date of a relevant standard are not subject to the preconstruction review requirements specified in paragraphs [(b)(3)](#b-3), (d), and (e) of this section.
  - (2) This section includes notification requirements for new affected sources and reconstructed affected sources that are not major-emitting affected sources and that are or become subject to a relevant promulgated emission standard after the effective date of a relevant standard promulgated under this part.
- (b) **Requirements for existing, newly constructed, and reconstructed sources.**
  - (1) A new affected source for which construction commences after proposal of a relevant standard is subject to relevant standards for new affected sources, including compliance dates. An affected source for which reconstruction commences after proposal of a relevant standard is subject to relevant standards for new sources, including compliance dates, irrespective of any change in emissions of hazardous air pollutants from that source.
  - (2) [Reserved]
  - (3) After the effective date of any relevant standard promulgated by the Administrator under this part, no person may, without obtaining written approval in advance from the Administrator in accordance with the procedures specified in paragraphs [(d)](#d) and [(e)](#e) of this section, do any of the following:
    - (i) Construct a new affected source that is major-emitting and subject to such standard;
    - (ii) Reconstruct an affected source that is major-emitting and subject to such standard; or
    - (iii) Reconstruct a major source such that the source becomes an affected source that is major-emitting and subject to the standard.
  - (4) After the effective date of any relevant standard promulgated by the Administrator under this part, an owner or operator who constructs a new affected source that is not major-emitting or reconstructs an affected source that is not major-emitting that is subject to such standard, or reconstructs a source such that the source becomes an affected source subject to the standard, must notify the Administrator of the intended construction or reconstruction. The notification must be submitted in accordance with the procedures in [§ 63.9(b)](/cfr/40/63.9.md?p=b).
  - (5) [Reserved]
  - (6) After the effective date of any relevant standard promulgated by the Administrator under this part, equipment added (or a process change) to an affected source that is within the scope of the definition of affected source under the relevant standard must be considered part of the affected source and subject to all provisions of the relevant standard established for that affected source.
- (c) [Reserved]
- (d) **Application for approval of construction or reconstruction.** The provisions of this paragraph implement [section 112(i)(1)](/cfr/40/112.md?p=i-1) of the Act.
  - (1) **General application requirements.**
    - (i) An owner or operator who is subject to the requirements of [paragraph (b)(3)](#b-3) of this section must submit to the Administrator an application for approval of the construction or reconstruction. The application must be submitted as soon as practicable before actual construction or reconstruction begins. The application for approval of construction or reconstruction may be used to fulfill the initial notification requirements of [§ 63.9(b)(5)](/cfr/40/63.9.md?p=b-5). The owner or operator may submit the application for approval well in advance of the date actual construction or reconstruction begins in order to ensure a timely review by the Administrator and that the planned date to begin will not be delayed.
    - (ii) A separate application shall be submitted for each construction or reconstruction. Each application for approval of construction or reconstruction shall include at a minimum:
      - (A) The applicant's name and address;
      - (B) A notification of intention to construct a new major affected source or make any physical or operational change to a major affected source that may meet or has been determined to meet the criteria for a reconstruction, as defined in [§ 63.2](/cfr/40/63.2.md) or in the relevant standard;
      - (C) The address (i.e., physical location) or proposed address of the source;
      - (D) An identification of the relevant standard that is the basis of the application;
      - (E) The expected date of the beginning of actual construction or reconstruction;
      - (F) The expected completion date of the construction or reconstruction;
      - (G) [Reserved]
      - (H) The type and quantity of hazardous air pollutants emitted by the source, reported in units and averaging times and in accordance with the test methods specified in the relevant standard, or if actual emissions data are not yet available, an estimate of the type and quantity of hazardous air pollutants expected to be emitted by the source reported in units and averaging times specified in the relevant standard. The owner or operator may submit percent reduction information if a relevant standard is established in terms of percent reduction. However, operating parameters, such as flow rate, shall be included in the submission to the extent that they demonstrate performance and compliance; and
      - (I) [Reserved]
      - (J) **Other information as specified in paragraphs (d)(2) and (d)(3) of this section.**
    - (iii) An owner or operator who submits estimates or preliminary information in place of the actual emissions data and analysis required in paragraphs [(d)(1)(ii)(H)](#d-1-ii-H) and (d)(2) of this section shall submit the actual, measured emissions data and other correct information as soon as available but no later than with the notification of compliance status required in [§ 63.9(h)](/cfr/40/63.9.md?p=h) (see [§ 63.9(h)(5)](/cfr/40/63.9.md?p=h-5)).
  - (2) **Application for approval of construction.** Each application for approval of construction must include, in addition to the information required in [paragraph (d)(1)(ii)](#d-1-ii) of this section, technical information describing the proposed nature, size, design, operating design capacity, and method of operation of the source, including an identification of each type of emission point for each type of hazardous air pollutant that is emitted (or could reasonably be anticipated to be emitted) and a description of the planned air pollution control system (equipment or method) for each emission point. The description of the equipment to be used for the control of emissions must include each control device for each hazardous air pollutant and the estimated control efficiency (percent) for each control device. The description of the method to be used for the control of emissions must include an estimated control efficiency (percent) for that method. Such technical information must include calculations of emission estimates in sufficient detail to permit assessment of the validity of the calculations.
  - (3) **Application for approval of reconstruction.** Each application for approval of reconstruction shall include, in addition to the information required in [paragraph (d)(1)(ii)](#d-1-ii) of this section—
    - (i) A brief description of the affected source and the components that are to be replaced;
    - (ii) A description of present and proposed emission control systems (i.e., equipment or methods). The description of the equipment to be used for the control of emissions shall include each control device for each hazardous air pollutant and the estimated control efficiency (percent) for each control device. The description of the method to be used for the control of emissions shall include an estimated control efficiency (percent) for that method. Such technical information shall include calculations of emission estimates in sufficient detail to permit assessment of the validity of the calculations;
    - (iii) An estimate of the fixed capital cost of the replacements and of constructing a comparable entirely new source;
    - (iv) The estimated life of the affected source after the replacements; and
    - (v) A discussion of any economic or technical limitations the source may have in complying with relevant standards or other requirements after the proposed replacements. The discussion shall be sufficiently detailed to demonstrate to the Administrator's satisfaction that the technical or economic limitations affect the source's ability to comply with the relevant standard and how they do so.
    - (vi) If in the application for approval of reconstruction the owner or operator designates the affected source as a reconstructed source and declares that there are no economic or technical limitations to prevent the source from complying with all relevant standards or other requirements, the owner or operator need not submit the information required in [paragraphs (d)(3)(iii) through (d)(3)(v)](#d-3-iii..d-3-v) of this section.
  - (4) **Additional information.** The Administrator may request additional relevant information after the submittal of an application for approval of construction or reconstruction.
- (e) **Approval of construction or reconstruction.**
  - (1)
    - (i) If the Administrator determines that, if properly constructed, or reconstructed, and operated, a new or existing source for which an application under [paragraph (d)](#d) of this section was submitted will not cause emissions in violation of the relevant standard(s) and any other federally enforceable requirements, the Administrator will approve the construction or reconstruction.
    - (ii) In addition, in the case of reconstruction, the Administrator's determination under this paragraph will be based on:
      - (A) The fixed capital cost of the replacements in comparison to the fixed capital cost that would be required to construct a comparable entirely new source;
      - (B) The estimated life of the source after the replacements compared to the life of a comparable entirely new source;
      - (C) The extent to which the components being replaced cause or contribute to the emissions from the source; and
      - (D) Any economic or technical limitations on compliance with relevant standards that are inherent in the proposed replacements.
  - (2)
    - (i) The Administrator will notify the owner or operator in writing of approval or intention to deny approval of construction or reconstruction within 60 calendar days after receipt of sufficient information to evaluate an application submitted under [paragraph (d)](#d) of this section. The 60-day approval or denial period will begin after the owner or operator has been notified in writing that his/her application is complete. The Administrator will notify the owner or operator in writing of the status of his/her application, that is, whether the application contains sufficient information to make a determination, within 30 calendar days after receipt of the original application and within 30 calendar days after receipt of any supplementary information that is submitted.
    - (ii) When notifying the owner or operator that his/her application is not complete, the Administrator will specify the information needed to complete the application and provide notice of opportunity for the applicant to present, in writing, within 30 calendar days after he/she is notified of the incomplete application, additional information or arguments to the Administrator to enable further action on the application.
  - (3) Before denying any application for approval of construction or reconstruction, the Administrator will notify the applicant of the Administrator's intention to issue the denial together with—
    - (i) Notice of the information and findings on which the intended denial is based; and
    - (ii) Notice of opportunity for the applicant to present, in writing, within 30 calendar days after he/she is notified of the intended denial, additional information or arguments to the Administrator to enable further action on the application.
  - (4) A final determination to deny any application for approval will be in writing and will specify the grounds on which the denial is based. The final determination will be made within 60 calendar days of presentation of additional information or arguments (if the application is complete), or within 60 calendar days after the final date specified for presentation if no presentation is made.
  - (5) Neither the submission of an application for approval nor the Administrator's approval of construction or reconstruction shall—
    - (i) Relieve an owner or operator of legal responsibility for compliance with any applicable provisions of this part or with any other applicable Federal, State, or local requirement; or
    - (ii) Prevent the Administrator from implementing or enforcing this part or taking any other action under the Act.
- (f) **Approval of construction or reconstruction based on prior State preconstruction review.**
  - (1) Preconstruction review procedures that a State utilizes for other purposes may also be utilized for purposes of this section if the procedures are substantially equivalent to those specified in this section. The Administrator will approve an application for construction or reconstruction specified in paragraphs [(b)(3)](#b-3) and (d) of this section if the owner or operator of a new affected source or reconstructed affected source, who is subject to such requirement meets the following conditions:
    - (i) The owner or operator of the new affected source or reconstructed affected source has undergone a preconstruction review and approval process in the State in which the source is (or would be) located and has received a federally enforceable construction permit that contains a finding that the source will meet the relevant promulgated emission standard, if the source is properly built and operated.
    - (ii) Provide a statement from the State or other evidence (such as State regulations) that it considered the factors specified in [paragraph (e)(1)](#e-1) of this section.
  - (2) The owner or operator must submit to the Administrator the request for approval of construction or reconstruction under this [paragraph (f)(2)](#f-2) no later than the application deadline specified in [paragraph (d)(1)](#d-1) of this section (see also [§ 63.9(b)(2)](/cfr/40/63.9.md?p=b-2)). The owner or operator must include in the request information sufficient for the Administrator's determination. The Administrator will evaluate the owner or operator's request in accordance with the procedures specified in [paragraph (e)](#e) of this section. The Administrator may request additional relevant information after the submittal of a request for approval of construction or reconstruction under this [paragraph (f)(2)](#f-2).