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Clean Air Markets

Emission Monitoring Regulatory Actions

Part 75 regulatory actions

This page summarizes regulatory actions for 40 CFR Part 75.

Refer to the Mercury and Air Toxics Standards (MATS) for information about MATS electronic data reporting using the Part 75 electronic reporting system.

EPA revised substitute data provisions for units with delayed quality assurance tests due to COVID-19

April 22, 2020 – EPA issued the interim final rule Continuous Emission Monitoring; Quality-Assurance Requirements During the COVID-19 National Emergency to temporarily amend the Part 75 emission monitoring and reporting regulations for the Acid Rain Program, Cross-State Air Pollution Rule (CSAPR), and the NOX SIP Call. The temporary amendments are designed to reduce the COVID-19 exposure risk to power plant and other essential personnel.  Under the temporary rule, power plant operators that cannot complete a required quality assurance activity due to travel, plant access, or other safety restrictions implemented to address the current COVID-19 national emergency can continue reporting valid, measured data. The additional reporting options provided by the temporary rule are no longer available as of October 19, 2020.

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EPA updated references to ASTM methods to provide alternatives to mercury-containing thermometers

January 18, 2012 – EPA issued the final rule Incorporation of Revised ASTM Standards That Provide Flexibility in the Use of Alternatives to Mercury- Containing Industrial Thermometers to incorporate the most recent versions of ASTM International (ASTM) standards.

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EPA updated and corrected the PGVP/AETB programs and §75.4

August 12, 2011 – EPA issued the final rule Protocol Gas Verification Program and Minimum Competency Requirements for Air Emission Testing; Corrections to correct and clarify the PGVP/AETB preamble and rule finalized in the March 28, 2011 rulemaking.

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EPA created the Air Emissions Testing Bodies and Protocol Gas Verification Programs

March 28, 2011 – EPA issued the final rule Protocol Gas Verification Program and Minimum Competency Requirements for Air Emission Testing to establish the Protocol Gas Verification Program (PGVP) and the Air Emission Testing Body (AETB) program. These are ongoing programs to ensure the accuracy of calibration gases and the competency of emission stack testers. Both programs enhance the quality of the emissions data reported to the Acid Rain Program, Cross-State Air Pollution Rule, and the Agency's other regional emission reduction programs.

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EPA updated reporting software requirements and ozone-season quality assurance schedules

January 24, 2008 – EPA issued the final rule Revisions to the Continuous Emissions Monitoring Rule for the Acid Rain Program, NOx Budget Trading Program, Clean Air Interstate Rule, and the Clean Air Mercury Rule to require affected units to report using the Emission Collection and Monitoring Plan System (ECMPS) and simplify the quality assurance/quality control (QA/QC) requirements for ozone season-only reporters. The changes to Part 75, Subpart H change the timing requirements for the relative accuracy test audits (RATAs) and the linearity checks to allow these QA/QC tests to be completed prior to the beginning of the ozone season.

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