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Title 40

Displaying title 40, up to date as of 10/08/2026. Title 40 was last amended 10/08/2026.
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§ 63.8690 How do I monitor and collect data to demonstrate continuous compliance?

(a) You must monitor and collect data according to this section.

(b) Before September 9, 2020, except for monitor malfunctions, associated repairs, and required quality assurance or control activities (including, as applicable, calibration checks and required zero and span adjustments), you must monitor continuously (or collect data at all required intervals) at all times that the affected source is operating including periods of startup, shutdown, and malfunction when the affected source is operating. On and after September 9, 2020, you must monitor and collect data at all times in accordance with § 63.8685(b), except during periods of nonoperation of the affected source (or specific portion thereof) resulting in cessation of the emissions to which this subpart applies.

(c) You may not use data recorded during monitoring malfunctions, associated repairs, and required quality assurance or control activities in data averages and calculations used to report emission or operating levels, nor may such data be used in fulfilling a minimum data availability requirement, if applicable. You must use all the data collected during all other periods in assessing the operation of the control device and associated control system.

[68 FR 24577, May 7, 2003, as amended at 85 FR 14549, Mar. 12, 2020]