part_subject: "NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED)"
subpart_code: "P"
subpart_subject: "PPPP—National Emission Standards for Hazardous Air Pollutants for Engine Test Cells/Stands"
section_number: "63.9335"
section_subject: "How do I monitor and collect data to demonstrate continuous compliance?"
cfr_reference: "40 CFR 63.9335"
title_name: "Title 40"
title_subject: "Protection of Environment"
parts_covered: "Part 63 (§ 63.8980 to end of part 63)"
revised_date: "Revised as of July 1, 2019"
publication_date: "As of July 1, 2019"
contains_description: "Containing a codification of documents of general applicability and future effect"
publication_info: "Published by the Office of the Federal Register National Archives and Records Administration as a Special Edition of the Federal Register"
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(a)Except for monitor malfunctions, associated repairs, and required quality assurance or quality control activities (including, as applicable, calibration drift checks and required zero and high-level adjustments of the monitoring system), you must conduct all monitoring in continuous operation at all times the engine test cell/stand is operating.
(b)Do not use data recorded during monitor malfunctions, associated repairs, and required quality assurance or quality control activities for meeting the requirements of this subpart, including data averages and calculations. You must use all the data collected during all other periods in assessing the performance of the emission control device or in assessing emissions from the new or reconstructed affected source.