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Air Emission Measurement Center (EMC)

Air Emission Measurement Center (EMC)

Optical Gas Imaging Stakeholder Workshop

EPA is hosting a virtual Optical Gas Imaging Stakeholder Workshop on November 9 and 10, 2020, in order to gather information from stakeholders prior to promulgating procedures for the use of optical gas imaging (OGI) for leak detection with a focus on leak detection in the refinery sector. 

For more information and to register for the workshop, see

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 Since there are no longer two providers, the requirement to obtain these audit samples is no longer in effect until such time as another independent AASP has audit samples available for purchase.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.