40 CFR 50.2 - Scope.

§ 50.2 Scope.

(a) National primary and secondary ambient air quality standards under section 109 of the Act are set forth in this part.

(b) National primary ambient air quality standards define levels of air quality which the Administrator judges are necessary, with an adequate margin of safety, to protect the public health. National secondary ambient air quality standards define levels of air quality which the Administrator judges necessary to protect the public welfare from any known or anticipated adverse effects of a pollutant. Such standards are subject to revision, and additional primary and secondary standards may be promulgated as the Administrator deems necessary to protect the public health and welfare.

(c) The promulgation of national primary and secondary ambient air quality standards shall not be considered in any manner to allow significant deterioration of existing air quality in any portion of any State or Indian country.

(d) The proposal, promulgation, or revision of national primary and secondary ambient air quality standards shall not prohibit any State or Indian country from establishing ambient air quality standards for that State or area under a tribal CAA program or any portion thereof which are more stringent than the national standards.

[ 36 FR 22384, Nov. 25, 1971, as amended at 63 FR 7274, Feb. 12, 1998]

This is a list of United States Code sections, Statutes at Large, Public Laws, and Presidential Documents, which provide rulemaking authority for this CFR Part.

This list is taken from the Parallel Table of Authorities and Rules provided by GPO [Government Printing Office].

It is not guaranteed to be accurate or up-to-date, though we do refresh the database weekly. More limitations on accuracy are described at the GPO site.


United States Code

Title 40 published on 17-Nov-2018 04:39

The following are ALL rules, proposed rules, and notices (chronologically) published in the Federal Register relating to 40 CFR Part 50 after this date.

  • 2018-06-08; vol. 83 # 111 - Friday, June 8, 2018
    1. 83 FR 26752 - Review of the Primary National Ambient Air Quality Standards for Sulfur Oxides
      GPO FDSys XML | Text
      ENVIRONMENTAL PROTECTION AGENCY
      Proposed action.
      Comments must be received on or before July 23, 2018. If, by June 15, 2018, the EPA receives a request from a member of the public to speak at a public hearing concerning the proposed decision (see SUPPLEMENTARY INFORMATION below), we will hold a public hearing, with information about the hearing provided in a subsequent notice in the Federal Register .
      40 CFR Part 50