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42 U.S.C. 7401 et seq.
57 FR 61992, Dec. 29, 1992, unless otherwise noted.
67 FR 45598, July 9, 2002, unless otherwise noted.
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Subscribe to: 40 CFR Part 63 Subpart XXXX - General Testing and Initial Compliance Requirements
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At 91 FR 37274, June 22, 2026, as required by the Congressional Review Act and Public Law 119-14, the Environmental Protection Agency removed all amendments to subpart XXXX of part 63 published at 89 FR 94886, Nov. 29, 2024.
(a) If you have a new or reconstructed affected source, you must conduct each required initial compliance demonstration or performance test within 180 calendar days after the compliance date that is specified for your new or reconstructed affected source in § 63.5983(a). If you are required to conduct a performance test, you must do so according to the provisions of § 63.7(a)(2).
(b) If you have an existing affected source, you must conduct each required initial compliance demonstration or performance test no later than the compliance date that is specified for your existing affected source in § 63.5983(b). If you are required to conduct a performance test, you must do so according to the provisions of § 63.7(a)(2).
(c) If you commenced construction or reconstruction between October 18, 2000 and July 9, 2002, you must demonstrate initial compliance with either the proposed emission limitations or the promulgated emission limitations no later than January 6, 2003, or within 180 calendar days after startup of the source, whichever is later, according to § 63.7(a)(2)(ix).
(d) If you commenced construction or reconstruction between October 18, 2000 and July 9, 2002, and you chose to comply with the proposed emission limitation when demonstrating initial compliance, you must conduct a second compliance demonstration for the promulgated emission limitation no later than January 5, 2006, or after startup of the source, whichever is later, according to § 63.7(a)(2)(ix).
If you use a control system (add-on control device and capture system) to meet the emission limitations, you must also conduct a performance test at least once every 5 years following your initial compliance demonstration to verify control system performance and reestablish operating parameters or operating limits for control systems used to comply with the emissions limits.
[67 FR 45598, July 9, 2002, as amended at 89 FR 94908, Nov. 29, 2024; 91 FR 37276, June 22, 2026]
(a) If you use a control system to meet the emission limitations, you must conduct each performance test in table 5 to this subpart that applies to you.
(b) Each performance test must be conducted according to the requirements in § 63.7(e)(1) and under the specific conditions specified in table 5 to this subpart.
(c) Before January 21, 2021, you may not conduct performance tests during periods startup, shutdown, or malfunction, as specified in § 63.7(e)(1). After January 20, 2021, performance tests shall be conducted under such conditions as the Administrator specifies to the owner or operator based on representative performance of the affected source for the period being tested. Representative conditions exclude periods of startup and shutdown unless specified by the Administrator or an applicable subpart. The owner or operator may not conduct performance tests during periods of malfunction. The owner or operator must record the process information that is necessary to document operating conditions during the test and include in such record an explanation to support that such conditions represent normal operation. Upon request, the owner or operator shall make available to the Administrator such records as may be necessary to determine the conditions of performance tests.
(d) Before January 21, 2021, you must conduct three separate test runs for each performance test required in this section, as specified in § 63.7(e)(1) unless otherwise specified in the test method. Each test run must last at least 1 hour. After January 20, 2021, you must conduct three separate test runs for each performance test required in this section, as specified in § 63.5993(c) above, unless otherwise specified in the test method. Each test run must last at least 1 hour.
(e) If you are complying with the emission limitations using a control system, you must also conduct performance tests according to the requirements in paragraphs (e)(1) through (3) of this section as they apply to you.
(1) Determining capture efficiency of permanent or temporary total enclosure. Determine the capture efficiency of a capture system by using one of the procedures in table 5 to this subpart.
(2) Determining capture efficiency of an alternative method. As an alternative to constructing a permanent or temporary total enclosure, you may determine the capture efficiency using any capture efficiency protocol and test methods if the data satisfy the criteria of either the Data Quality Objective or the Lower Confidence Limit approach in appendix A to subpart KK of this part.
(3) Determining efficiency of an add-on control device. Use table 5 to this subpart to select the test methods for determining the efficiency of an add-on control device.
[67 FR 45598, July 9, 2002, as amended at 85 FR 44761, July 24, 2020; 89 FR 94908, Nov. 29, 2024; 91 FR 37276, June 22, 2026]