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Air Emission Measurement Center (EMC)

  • The EPA hub for stationary source air emissions test methods and procedures.

NOTICE: It has come to our attention that one of the two providers of audit samples has ceased manufacturing samples for the stationary source audit program.  The general provisions to 40 CFR Parts 60 and 63 (see §60.8(g)(1) and §63.7(c)(2)(iii)(A)) require that the owner or operator obtain audit samples if the audit samples are  “commercially available” and have defined “commercially available” as two or more independent accredited audit sample providers (AASP) to have blind audit samples available for purchase. Since there are no longer two providers, the requirement to obtain these audit samples is no longer in effect until such time as another independent AASP has audit samples available for purchase.

When there are two or more AASP with audit samples available for purchase, we will update this webpage with the name or names of the providers and audit sample(s) available for purchase. At that time, this information must be listed on the EMC website for 60 days before audits are required again.

The Air Emission Measurement Center (EMC) provides information on test methods for measuring pollutants from smokestacks and other industrial sources. This website compiles the test methods available for emission measurement. Contact EMC staff for technical assistance in the use and application of the methods.

Recent Updates
  • December 2022: Concern with Certain Calibration Gas Mixtures Sold as Protocol Gases Not Meeting Long-Term Stability Requirements 
  • April 2022:  Proposed Revisions to Test Methods and Performance Specifications for Air Emission Sources
  • January 2022: OTM-46 Measurement of Polychlorinated Dibenzo-p-Dioxins, Polychlorinated Dibenzofurans, Polychlorinated Biphenyls, and Polycyclic Aromatic Hydrocarbons from Stationary Sources
  • January 2022: Withdrawal of the Approval of Broadly Applicable Alternate Test Methods ALT-125 and ALT-127
  • February 2021: GD 54 - EPA Source Test Observation and Report Review Checklists
  • January 2021:  Other Test Method 45 (OTM-45) Measurement of Selected Per- and Polyfluorinated Alkyl Substances from Stationary Sources

Test Methods

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Monitoring

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Instructional Material

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Learn about EMC

  • What is the EMC?
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Technical Support

  • Technical Support for Quality Assurance, Audit Program, etc.
  • EMC Methods Support Directory

Additional Resources

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Contact Us to ask a question, provide feedback, or report a problem.
Last updated on December 20, 2022
United States Environmental Protection Agency

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