part_subject: "REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS"
subpart_code: "H"
subpart_subject: "Prevention of Air Pollution Emergency Episodes"
section_number: "51.153"
section_subject: "Reevaluation of episode plans."
cfr_reference: "40 CFR 51.153"
title_name: "Title 40"
title_subject: "Protection of Environment"
parts_covered: "Parts 50 to 51"
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"
---
(a)States should periodically reevaluate priority classifications of all Regions or portion of Regions within their borders. The reevaluation must consider the three most recent years of air quality data. If the evaluation indicates a change to a higher priority classification, appropriate changes in the episode plan must be made as expeditiously as practicable.