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Air Emission Measurement Center (EMC)

EMC Technical Support

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QA Activities and Information

The Emission Measurement Center's (EMC's) Quality Assurance (QA) Team has been very active over the past few years trying to increase QA activities within the stationary source program. In September of 1996, the Office of Air Quality Planning and Standards (OAQPS) received approval of the Quality Management Plan (QMP) which describes how QA would operate within OAQPS. One responsibility of the EMC QA Team is to make sure all stationary source work has proper QA associated with it. With the divestment of QA support from the Office of Research and Development (ORD), the EMC QA Team has acquired some additional responsibilities including: the Stationary Source Compliance Audit Program (SSCAP), Volume III of the QA Handbooks, and Method Development and Field Validation work.

In order to coordinate QA activities and pass on important information about QA to the regional, state, and the local agencies, the EMC QA Team holds a monthly conference call the first Monday of each month to discuss these issues, along with other stack testing issues of interest to participants. If you would like more information about this conference call or further QA information, please contact any member of the EMC QA Team. If you are interested in any of the QA Requirement Documents or Guidance Documents they can be found on the EPA Quality Program website.

EMC QA Team Members

  1. Lula Melton (919) 541-2910 or by E-Mail
  2. Mike Toney (919) 541-5247 or by E-Mail

Quality Assurance Project Plan

Since 1997, the Agency has required that a Quality Assurance Project Plan (QAPP) be written for any activity that involves an environmental data operation (EDO), as documented in EPA QA/R-5: "EPA Requirements for Quality Assurance Project Plans for Environmental Data Operations". An additional source of information provided by the Quality Assurance Division (QAD) to assist with writing a QAPP is document EPA QA/G-5: "EPA Guidance for Quality Assurance Project Plans". Both of these documents and other important QA materials can be found on the EPA Quality Program website.

Over the past few years, individuals that work with the Agency have become very proficient when writing QAPPs. There are still many groups, though, that have not had to produce such documentation. This Quality Assurance Project Plan document(65 pp, 4 MB, About PDF) is an example of the type of content expected (i.e., level of detail) in an acceptable QAPP. Many different formats and styles have been followed that are equally acceptable. This file is being made available only as an example of the type/level of information expected.

Quality Assurance Handbooks

The last two versions of the Quality Assurance Handbook for Air Pollution Measurement Systems Volume III, Stationary Source Specific Methods (QA Handbook) supplement the procedures published in the Federal Register. The most recent version of the QA Handbook, which was published in 1994, covers 78 stationary source test methods published in 40CFR60 and 40CFR61 but provides limited details. The prior version, which the latest supplement was published around 1988 only covers 20 test methods but provides substantial detail. As such, we consider these documents to be complementary and the information in each is useful to persons engaged in conducting or reviewing stationary source test programs.

We have divided the 1994 version of the QA Handbook into many small files. Part I of the handbook(66 pp, 715 K, About PDF) provides an overview of the content of source test plans and source test reports. Part II of the handbook describes the salient features of the test methods. A directory of Part I of the handbook(7 pp, 335 K, About PDF) provides links between the 78 test methods covered and the related files. While information published in this handbook was current in 1994, many source test methods covered in the handbook have been updated. As such, the reader should not rely solely on the contents of this handbook.

We have also divided the 1977 version of the QA Handbook into a few large files. The Table of Contents for this handbook(6 pp, 308 K, About PDF) provides links to the 20 methods covered. As with the 1994 version of the QA Handbook, the test methods covered in this document have been updated since publication. Readers should use this document as a source of background information and detailed concepts required for the proper planning, conduct and evaluation of source test programs.

Relationship Between the 1977 and 1994 QA Handbooks

In early 1988, EPA ceased supplementing the 1977 version of the Handbook and began preparing a more concise but updated version of the QA Handbook for stationary sources (published in September 1994). Although the number of source test methods increased from 20 to 78, the handbook was made more concise. Removing the copy of the original test method reduced the size and promotes the use of the most current test method as published in the Federal Register. The handbook was further reduced in size by removing duplication between methods. Providing only the information on the features that make the test method unique was the third change, reducing the size of the handbook further. While reducing the volume of information required to properly conduct and assess the quality of a source emissions test did not detract from the document's usefulness by staff experienced in these activities, much of the detail and rationale that is useful to less experienced staff was no longer available in a single document. As a result, we are providing access to both versions of Volume III. Users are cautioned that neither of these documents have been updated since they were published and that many of the test methods have been revised and program responsibilities changed. Users are also advised that while these documents present procedures and information that are reflective of good practice, the guidance provided in these documents has no legal standing unless the CFR specifically requires the tester to follow Volume III.

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Electronic Reporting Tool

The Electronic Reporting Tool (ERT), a Microsoft Access desktop application, is an electronic alternative for paper source test reports documenting EPA's emissions measurement methods for stationary sources. The test methods supported by ERT Version 5 include the following: Methods 1 through 4, 3A, 5, 5A, 5B, 5F, 5G, 6C, 7E, 8, 10, 12, 13A, 13B, 17, 23, 0023A, 25A, 25B, 26, 26A, Modified Method 26A Subpart S, 29, 101, 101A, 102, 103, 104, 108, 201A, 202, 0010, 0011, 0061, 30B, 306, 306A, 308, 315, 316, CARB 428, CARB 429, Conditional Test Method 27, and Other Test Method 29. Performance Specifications 2, 3, 4 and 8.  Custom test methods are also supported when the pollutant CAS number is available. The ERT replaces the: (1) time-intensive manual preparation and transcription of stationary source emissions test plans and reports currently performed by contractors, and (2) time-intensive manual quality assurance valuations and documentation performed by State agencies. The submissions of electronic test data through EPA's Central Data exchange through the use of the ERT is required for several source categories by recent rules. The ERT provides a format that:

  • Highlights the need to document the key information and procedures required by the existing EPA Federal Test Methods;
  • Facilitates coordination among the source, the test contractor, and the regulatory agency in planning and preparing for the emissions test;
  • Provides for consistent criteria to quantitatively characterize the quality of the data collected during the emissions test;
  • Standardizes the reports; and
  • Provides for future capabilities to electronically exchange information in the reports with facility, State or Federal data systems.

In addition to improving the content and quality of source emissions test reports, the ERT should:

  • Reduce the workload associated with manual transcription of information and data contained in the report;
  • Reduce the resources required to store and access the reports; and
  • Reduce redundant efforts in using the data for multiple purposes.

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EPA 2003 Blind Audit of Protocol Calibration Gases for CEMS

In the 1980s and 1990s EPA conducted a series of performance audits of EPA Protocol gases sold by specialty gas producers. The program was discontinued in 1998. Because there had not been an audit in 7 years and EPA was concerned that gas quality may have declined, EPA performed an audit in 2003. EPA audited 42 source-level, tri-blend, EPA Protocol calibration gas cylinders from a total of 14 major gas vendors nationwide. The cylinders contain blends of SO2, NO, and CO2 in a N2 balance. The gas concentrations are (1) 50 ppm SO2, 50 ppm NO, and 5% CO2; (2) 500 ppm SO2, 400 ppm NO, and 12% CO2; and (3) 1000 ppm SO2, 900 ppm NO, and 18% CO2. The cylinders were purchased by a third party so that the gas vendors did not know that EPA was analyzing the cylinders. The purpose of the audit was to help vendors improve gas quality, and to help calibration gas buyers identify good gas vendors. The overall failure rate was 11% on a gas component basis, and 57% on a vendor basis. The 2003 audit has provided useful information to help establish an ongoing EPA Protocol gas audit program.

To arrive at final results, EPA overcame several problems. We initially used an API chemiluminescence monitor to measure the NO component in each cylinder. Interference with the NO readings caused by the CO2 component (quenching effect), however, forced us to discard these results. We then obtained a UV NO analyzer to repeat the analyses. However, for the high level NO cylinders, we relied on our FTIR results instead of UV because the AMETEK UV NOx analyzer was set up for 0-500 ppm instead of 0-1000 ppm. For high level CO2 cylinders, we relied on the NDIR results because there was not enough high level CO2 SRM or NTRM to use as a reference spectra for the FTIR. We found that SO2 in the cylinders was interfering with the NO readings from the AMETEK UV analyzer. A correction was developed by injecting the analyzer with SO2 in N2 and observing the effect on NO readings.

Summary tables of EPA's results are available at: then scroll to "EPA 2003 Blind Audit of Protocol Calibration Gases for CEMS".

The EPA Traceability Protocol for Assay and Certification of Gaseous Calibration Standards (Section 1-4 and and spreadsheets to support the protocol Appendices) is available on the Air Research webpage, EPA Traceability Protocol for Assay and Certification of Gaseous Calibration Standards.

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Audit Program

Monthly QA Call: On the first Monday of every month we hold a QA call from 1:30 to 3:00 p.m. (EST). The call started out as a venue to discuss only QA issues, but has since evolved into a QA and stationary source emission testing call. Any Regional, State, or local compliance authority is welcome to attend the conference call. An agenda will be drafted around one week before the conference call and participants are welcome to submit topics for discussion. If you would like to be placed on the QA call e-mail list, send an e-mail request to Kim Garnett at with your name, agency, phone number and e-mail address.

Restructuring of SSAP Final Rule: On September 13, 2010, the U.S. Environmental Protection Agency (EPA) issued the final rule to restructure the stationary source audit program (SSAP). This program provides criteria to assure that the analyst and the field testing personnel are sufficiently capable of conducting emissions testing for compliance with the Clean Air Act requirements. Audit samples must be analyzed along with the samples collected while testing for regulatory compliance. This analysis helps the regulatory agency determine the validity of compliance test results. The changes finalized in this rule allow accredited providers to supply the audit samples and require sources to obtain and use audit samples obtained from the accredited providers instead of EPA, as was the former practice. In addition, this action moves the requirements for audits from EPA’s rules laying out individual emissions test methodologies to generalized requirements in the general provisions of the Clean Air Act.

List of Approved Sample Programs

  • The NELAC Institute (TNI) Stationary Source Audit Program: The EPA has approved the TNI Stationary Source Audit Program to provide accredited audit samples based on three documents. These three documents outline the requirements for the audit sample providers, the accreditor of audit sample providers, and the requirements for participation in the TNI audit program are available through the TNI website.Exit

List of Accredited Audit Sample Providers and Audit Samples

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.

Additional Information

Additional information pertaining to the methods can be found on the Frequent Questions webpage. This page explains the Test Methods Numbering System, Guideline Documents, Information Documents, and other frequently asked questions.

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