40 CFR 63.5355 - How do I monitor and collect data to demonstrate continuous compliance?
(a) You must monitor and collect data according to this section.
(c) For emission control devices, 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.
(d) 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 compliance ratio, and, if an emission control device is used, in assessing the operation of the control device.