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Title 40

Displaying title 40, up to date as of 10/09/2026. Title 40 was last amended 10/09/2026.
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§ 63.2170 How do I monitor and collect data to demonstrate continuous compliance?

(a) You must monitor and collect data according to this section and § 63.2163 or § 63.2164.

(b) Except for periods of monitoring system malfunctions, required monitoring system quality assurance or control activities (including, as applicable, calibration checks and required zero and span adjustments), and any scheduled maintenance, you must collect data using the CEMS or brew ethanol monitor, as applicable, at all times during each batch monitoring period.

(c) You may not use data recorded during monitoring malfunctions, associated repairs, and required quality assurance or quality control activities in data averages and calculations used to report emission or operating levels, or to fulfill a data collection requirement. You must use all the data collected during all other periods in assessing the operation of the control system.

(d) Any hour during the batch monitoring period for which quality-assured VOC CEMS data or brew ethanol monitor data, as applicable, are not obtained is a deviation from monitoring requirements and is counted as an hour of monitoring system downtime.