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Regulations last checked for updates: Oct 08, 2025
Title 40 - Protection of Environment last revised: Sep 08, 2029
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Title 40
Chapter I
Part 51
Subpart J - Subpart J—Ambient Air Quality Surveillance
§ 51.190 - Ambient air quality monitoring requirements.
authority:
23 U.S.C. 101
;
42 U.S.C. 7401-7671q.
source:
36 FR 22398, Nov. 25, 1971, unless otherwise noted.
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