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42 U.S.C. 7401 et seq.
36 FR 24877, Dec. 23, 1971, unless otherwise noted.
91 FR 11833, Mar. 10, 2026, unless otherwise noted.
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(a) Conduct annual relative accuracy test audits of your continuous emission monitoring systems no less than 9 calendar months and no more than 15 calendar months following the previous performance test; you must complete five relative accuracy test audits in each 5-year calendar period.
(b) Evaluate your continuous emission monitoring systems daily and quarterly as specified in procedure 1 in appendix F of this part.