
MEMORANDUM

SUBJECT:	Voluntary Consensus Standard Results for Subpart I  -  Electronics Manufacturing, of the Greenhouse Gas Reporting Rule

FROM:	Alexis McKittrick, EPA/OAR/CCD 

TO:	EPA Docket No. EPA-HQ-OAR-2011-0028

DATE:	August 27, 2012
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The EPA conducted searches and reviews of methods to address the National Technology Transfer and Advancement Act (NTTAA) requirements on the use of voluntary consensus standards (VCS).  The NTTAA directs EPA to use VCS in regulatory and procurement activities unless doing so would be inconsistent with applicable law or otherwise impractical. This memorandum documents the results of the VCS searches and reviews to determine if VCS are available and practical for use in lieu of stationary source methods cited in the Proposed Amendments and Confidentiality Determinations for Subpart I  -  Electronics Manufacturing, of the Greenhouse Gas Reporting Rule. The EPA is proposing to include a stack testing option that would involve using the following EPA reference methods: 

       Method 1 or 1A at 40 CFR part 60, appendix A-1, to select sampling port locations and the number of traverse points in the exhaust stacks. 
       Method 2, 2A, 2C, 2D, 2F, or 2G at 40 CFR part 60, appendix A-1 and A-2, to determine gas velocity and volumetric flow rate in the exhaust stacks.
       Method 3, 3A, or 3B at 40 CFR part 60, appendix A-2, to determine the gas molecular weight of the exhaust using the same sampling site and at the same time as the fluorinated greenhouse gas (F-GHG) sampling is performed.
       Method 4 at 40 CFR part 60, appendix A-3, to measure gas moisture content in the exhaust stacks.
       Method 301 at 40 CFR part 63, appendix A, to perform field validations of alternative methods of measuring F-GHG emissions and abatement system destruction or removal efficiency (DRE).
       Method 320 at 40 CFR part 63, appendix A, to measure the concentration of F-GHG in the stack exhaust.
         
In 1998, the EPA began implementing the requirements of the NTTAA by conducting searches to identify VCS. Searches continue to be performed to meet the requirements of the NTTAA. While we have made a reasonable effort to identify and evaluate potentially practical VCS, our findings do not necessarily represent all potential alternative standards which may exist. 

The EPA participates in the American Society for Testing and Materials (ASTM), which is one of the most active VCS organizations on emissions testing, and has been invited to participate in the USA Technical Advisory Group for International Organization for Standardization (ISO) relating to emissions monitoring. We expect these additional efforts will help us to support a periodic review of all EPA reference methods and performance standards for possible incorporation by reference (IBR) of VCS in lieu of or as alternatives to EPA procedures. We anticipate that these activities will provide an opportunity for further review, consideration and possible IBR of VCS overlooked in the National Standards Service Network (NSSN) searches or finalized after Federal agency review in the EPA rulemaking process.

We conducted searches for the Proposed Amendments for Subpart I  -  Electronics Manufacturing, of the Greenhouse Gas Reporting Rule through the Enhanced NSSN Database managed by the American National Standards Institute (ANSI). We also contacted VCS organizations, including the International SEMATECH Manufacturing Initiative (ISMI), and accessed and searched their databases.

Searches were conducted for EPA Methods 1, 1A, 2, 2A, 2C, 2D, 2F, 2G, 3, 3A, 3B, and 4 of 40 CFR part 60, Appendix A, and EPA Methods 301 and 320 of 40 CFR part 63, Appendix A. No applicable VCS were identified for EPA Methods 1A, 2A, 2D, 2F, 2G, or 3A. 

During the search, if the title or abstract (if provided) of the VCS described technical sampling and analytical procedures that are similar to EPA's referenced method, the EPA considered it as a potential equivalent method. All potential standards were reviewed to determine the practicality of the VCS for the proposed rule. The review required significant method validation data which meet the requirements of EPA Method 301 for accepting alternative methods, or a scientific, engineering, and policy evaluation to determine if it is equivalent to procedures in EPA reference methods. The EPA may reconsider determinations of impracticality if additional information becomes available for a particular VCS.

The search identified 12 VCS that were potentially applicable for use in the proposed rule in lieu of EPA reference methods. After reviewing the available standards, EPA determined that the 12 potential VSC identified for measuring emissions of pollutants subject to Subpart I would not be practical due to lack of equivalency, documentation, validation data, and other important technical and policy considerations. These 12 methods are listed in Table 1 of this memorandum, along with EPA review comments.

The EPA also examined the ISMI 2009 Guideline for Environmental Characterization of Semiconductor Process Equipment  -  Revision 2, as a replacement for the ISMI 2006 Guideline that is referenced in the EPA protocol for determining abatement system DRE (the DRE protocol is incorporated by reference for use in subpart I).  The EPA did not propose using of the entire ISMI 2009 Guideline as an alternative to the ISMI 2006 Guideline because only portions of the ISMI 2006 and 2009 Guidelines are relevant to determining abatement system DRE, and because industry members and the ISMI have identified additional changes that will be incorporated into a future version of the ISMI Guideline. However, EPA considered portions of the 2009 ISMI Guideline, with modifications, that may be used as an alternative to the ISMI 2006 Guideline procedures referenced in the EPA's DRE Protocol to provide flexibility and reduce burden, and has incorporated these adapted portions into the proposed rule. The 2009 ISMI Guideline includes a method to measure abatement system flow and to account for dilution that may occur between the inlet and out of the abatement system by measuring the change in concentration of a non-reactive tracer gas introduced into to the abatement system flow. To ensure thorough mixing of the tracer, the 2009 ISMI Guideline requires sources to measure the concentration at least eight duct diameters downstream of the injection site. Because of the presence of short ducts in POU abatement systems, these specifications would not be appropriate for several sources. Therefore, the EPA is proposing that facilities use procedures adapted from Section 8.1 of EPA Method 7E, Determination of Nitrogen Oxides Emissions From Stationary Sources (Instrumental Analyzer Procedure), in 40 CFR part 60, Appendix A-4, to establish that the injected tracer is well mixed in the duct system and is not stratified (i.e., poorly mixed). The relevant portions of the ISMI 2009 Guideline and the adaptation of the procedures from Section 8.1 of EPA Method 7E are incorporated into proposed Appendix A to subpart I. 
 



Table 1. List of Voluntary Consensus Standards Not Applicable to the Proposed Amendments to Subpart I  -  Electronics Manufacturing, of the Greenhouse Gas Reporting Rule
EPA Standard Reference Method(s)
Similar Voluntary Consensus Standard
EPA's Comments on VCS
EPA Methods 1, 2, 2C, 3, 3B, 4
ASTM D3154-00 (2006)  -  Standard Method for Average Velocity in a Duct (Pitot Tube Method)
This method is impractical as an alternative to EPA Methods 1, 2, 3, and 3B for the purposes of the proposed rule because the standard appears to lack in quality control and quality assurance requirements. Specifically, ASTM D3154 does not include the following: (1) proof that openings of standard pitot tubes have not plugged during the test; (2) if differential pressure gauges other than inclined manometers (e.g., magnehelic gauges) are used, their calibration must be checked after each test series; and (3) the frequency and validity range for calibration of the temperature sensors.
EPA Method 2
ASTM D3464-96 (2007)  -  Standard Test Method Average Velocity in a Duct Using a Thermal Anemometer
The applicability specifications in this ASTM standard are not clearly defined, e.g., range of gas composition, temperature limits.  Also, the lack of supporting quality assurance data for the calibration procedures and specifications, and certain variability issues that are not adequately addressed by the standard, limit EPA's ability to make a definitive comparison of the method in these areas.
EPA Method 2
ASTM D3796-90 (2004)  -  Standard Practice for Calibration of Type S Pitot Tubes
This ASTM method is intended to be a calibration procedure for the S-type pitot tube and not a method by which stack gas velocity and/or volumetric flowrates can be measured as in EPA Method 2. The calibration procedure does not require an inclined manometer and does not specify any additional accuracy verifications for the use of other types of differential pressure gauges.
EPA Methods 2, 3A, 4
ASME B133.9-1994 (2004)  -  Measurement of Exhaust Emissions from Stationary Gas Turbine Engines (Revision of ANSI [American National Standards Institute] B122.9-1979)
This method is impractical as an alternative to EPA Methods 2, 3A, and 4 in the proposed rule. This method applies to engines that operate on natural gas and liquid distillate fuels, and is not a quantitative method.
EPA Method 3A
ASTM D5835-95 (2001)  -  Standard Practice for Sampling Stationary Source Emissions for Automated Determination of Gas Concentration

ISO 10396:1993  -  Stationary Source Emissions: Sampling for the Automated Determination of Gas Concentrations
These standards are impractical alternatives to EPA Method 3A for the purposes of the proposed rule because they lack in detail and quality assurance/quality control requirements. Specifically, these two standards do not include the following: (1) sensitivity of the method; (2) acceptable levels of analyzer calibration error; (3) acceptable levels of sampling system bias; (4) zero drift and calibration drift limits, time span, and required testing frequency; (5) a method to test the interference response of the analyzer; (6) procedures to determine the minimum sampling time per run and minimum measurement time; and (7) specifications for data recorders, in terms of resolution and recording intervals.
EPA Method 3A
ISO 12039:2001  -  Stationary Source Emissions  -  Determination of Carbon Monoxide, Carbon Dioxide, and Oxygen  -  Automated Methods
This method is not acceptable as an alternative to EPA Method 3A. This ISO standard is similar to EPA Method 3A but is missing some key features. In terms of sampling, the hardware required by ISO 12039:2001 does not include a 3-way calibration valve assembly or equivalent to block the sample gas flow while calibration gases are introduced. In its calibration procedures, ISO 12039:2001 only specifies a two-point calibration while EPA Method 3A specifies a three-point calibration.  Also, ISO 12039:2001 does not specify performance criteria for calibration error, calibration drift, or sampling system bias tests as in the EPA method, although checks of these quality control features are required by the ISO standard.
EPA Methods 3A and 3B
ANSI/ASME PTC 19.10-1981-Part 10  -  Flue and Exhaust Gas Analyses
This method is not acceptable as a substitute for EPA Method 3A and 3B for measuring the oxygen, carbon dioxide, and carbon monoxide content of the exhaust gas. This ANSI/ASME standard includes manual and instrumental methods. The instrument methods are only general descriptions of procedures and are not true methods. Therefore, while some of the manual methods in the ANSI/ASME standard are acceptable alternatives to EPA methods, the instrumental procedures are not.
EPA Method 3A
ASTM D6522-00 (2005)  -  Standard Test Method for the Determination of Nitrogen Oxides, Carbon Monoxide, and Oxygen Concentrations in Emissions from Natural Gas-Fired Reciprocating Engines, Combustion Turbines, Boilers and Process Heaters Using Portable Analyzers
This method is impractical as an alternative to Method 3A in the proposed rule. This method applies to engines, turbines, and boilers and process heaters that operate on natural gas. 
EPA Method 3A
CAN/CSA [Canadian Standards Association] Z223.2-M86 (1999)  -  Method for the Continuous Measurement of Oxygen, Carbon Dioxide, Carbon Monoxide, Sulphur Dioxide, and Oxides of Nitrogen in Enclosed Combustion Flue Gas Streams
This standard is impractical as a substitute for EPA Method 3A, since it does not include quantitative specifications for measurement system performance, most notably the calibration procedures and instrument performance characteristics. The instrument performance characteristics that are provided are non-mandatory and also do not provide the same level of quality assurance as the EPA methods. For example, the zero and span/calibration drift is only checked weekly, whereas the EPA methods requires drift checks after each run.
EPA Method 301
ASTM D4855-97 (2002)  -  Standard Practice for Comparing Test Methods
This ASTM standard is equivalent to EPA Method 301 in its statistical design and decision criteria, but is less prescriptive than Method 301 for many procedures, and is not being proposed as an alternative to Method 301. For example, the ASTM standard does not require the use of a t-test explicitly to test the precision of the alternative method, but instead states that a t-test or F-test should be used, as appropriate. The primary difference between ASTM D4855-97 and EPA Method 301, that makes the ASTM standard not acceptable as a complete alternative to the EPA method, is that the ASTM method addresses the testing of materials rather than environmental samples. Because of this difference, the ASTM standard does not prescribe the use of paired samples as in the EPA method. This feature of EPA Method 301 is critical to its success and the acceptability of an alternative standard. 
EPA Method 320
ASTM D6348 - 03 (2010), Determination of Gaseous Compounds by Extractive Direct Interface Fourier Transform (FTIR) Spectroscopy
This test method employs an extractive sampling system to direct stationary source exhaust to an FTIR spectrometer for the identification and quantification of gaseous compounds that (1) have sufficient vapor pressure to be transported to the FTIR spectrometer and (2) absorb a sufficient amount of infrared radiation to be detected. Because emissions from the electronics manufacturing industry contain F-GHG in relatively low concentrations, and because all data previously received in support of stack testing used EPA Method 320, the EPA would need to consider more supporting data before approving ASTM D6348 as an alternative to EPA Method 320.

