40 CFR 50.3 - Reference conditions.

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There is 1 rule appearing in the Federal Register for 40 CFR Part 50. View below or at eCFR (GPOAccess)
§ 50.3 Reference conditions.
All measurements of air quality that are expressed as mass per unit volume (e.g., micrograms per cubic meter) other than for particulate matter (PM2.5) standards contained in §§ 50.7 and 50.13 and lead standards contained in § 50.16 shall be corrected to a reference temperature of 25 (deg) C and a reference pressure of 760 millimeters of mercury (1,013.2 millibars). Measurements of PM2.5 for purposes of comparison to the standards contained in §§ 50.7 and 50.13 and of lead for purposes of comparison to the standards contained in § 50.16 shall be reported based on actual ambient air volume measured at the actual ambient temperature and pressure at the monitoring site during the measurement period.
[73 FR 67051, Nov. 12, 2008]

Title 40 published on 2014-07-01.

The following are only the Rules published in the Federal Register after the published date of Title 40.

For a complete list of all Rules, Proposed Rules, and Notices view the Rulemaking tab.

  • 2015-03-06; vol. 80 # 44 - Friday, March 6, 2015
    1. 80 FR 12264 - Implementation of the 2008 National Ambient Air Quality Standards for Ozone: State Implementation Plan Requirements
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      ENVIRONMENTAL PROTECTION AGENCY
      Final rule.
      This final rule is effective on April 6, 2015.
      40 CFR Parts 50, 51, 52, 70, and 71

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United States Code

Title 40 published on 2014-07-01

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

  • 2015-04-03; vol. 80 # 64 - Friday, April 3, 2015
    1. 80 FR 18177 - Fine Particulate Matter National Ambient Air Quality Standards: State Implementation Plan Requirements
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      ENVIRONMENTAL PROTECTION AGENCY
      Notice of public hearing and extension of comment period.
      Public Hearing. The public hearing will be held on April 29, 2015, in Washington, DC Please refer to SUPPLEMENTARY INFORMATION for additional information on the public hearing. Comments . Comments must be received on or before May 29, 2015.
      40 CFR Parts 50, 51, and 93