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Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods: Designation of Two New Equivalent Methods

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Environmental Protection Agency.


Notice of the designation of two new equivalent methods for monitoring ambient air quality.


Notice is hereby given that the Environmental Protection Agency (EPA) has designated, in accordance with 40 CFR Part 53, two new equivalent methods for measuring concentrations of PM10 and sulfur dioxide (SO2) in the ambient air.

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Surender Kaushik, Human Exposure and Atmospheric Sciences Division (MD-D205-03), National Exposure Research Laboratory, U.S. EPA, Research Triangle Park, North Carolina 27711. Phone: (919) 541-5691, e-mail:

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In accordance with regulations at 40 CFR Part 53, the EPA evaluates various methods for monitoring the concentrations of those ambient air pollutants for which EPA has established National Ambient Air Quality Standards (NAAQSs) as set forth in 40 CFR Part 50. Monitoring methods that are determined to meet specific requirements for adequacy are designated by the EPA as either reference methods or equivalent methods (as applicable), thereby permitting their use under 40 CFR Part 58 by States and other agencies for determining compliance with the NAAQSs.

The EPA hereby announces the designation of two new equivalent methods for measuring concentrations of PM10 and SO2 in the ambient air. These designations are made under the provisions of 40 CFR Part 53, as amended on November 12, 2008 (73 FR 67057-67059).

The new PM10 equivalent method is an automated monitoring method utilizing a measurement principle based on sample collection by filtration and analysis by beta-ray attenuation. The newly designated equivalent method is identified as follows:

EQPM-0810-193, “OPSIS Model SM200 Monitor,” beta gauge semi-continuous ambient particulate monitor operated for 24 hours at a flow rate of 16.67 LPM between 5° and 40 °C using 47 mm PTFE membrane filter media, in the mass measurement range of 0 to 60 mg, configured with a BGI Model SSI25 PM10 inlet meeting criteria specified in 40 CFR 50 Appendix L, with a roof mounting kit, and with or without an inlet tube heater (as recommended based on site RH conditions), according to the SM200 User's Guide.

The new SO2 equivalent method is an automated method (analyzer) that utilizes a measurement principle based on ultraviolet fluorescence. The newly designated equivalent method is identified as follows:

EQSA-0810-194, “SERES model SF 2000 G Sulfur Dioxide Analyzer,” UV fluorescence method using a wavelength source approaching 215 nm and a selective membrane for aromatic hydrocarbon removal, operated with a full scale Start Printed Page 51040measurement range of 0-0.5 ppm at any ambient temperature in the range of 20 °C to 30 °C, with tabletop or rack mounts, microprocessor controlled menu-driven user interface, onboard diagnostics and system test functions, analog output signals of 4-20 mA or user selectable voltage ranges up to 10 V, printer port, modem port and 32 pin data/control/alarm port, user selectable manual and automatic zero/span and calibrate modes; with or without a permeation tube system (optional equipment) for internal calibration; operated in accordance with the SF 2000 G User and Maintenance Manual.

The applications for equivalent method determinations for these candidate methods were received by the EPA on June 22, 2007 and June 23, 2010, respectively. The OPSIS monitor is commercially available from the applicant, OPSIS Inc., 150 N. Michigan Ave., Suite 1950, Chicago, IL 60601. The SERES analyzer is available from the applicant, SERES, 360 Rue Louis de Broglie, La Duranne—BP 20087, 13793 Aix en Provence, Cedex 3, France.

Test analyzers representative of these methods have been tested in accordance with the applicable test procedures specified in 40 CFR Part 53 (as amended on November 12, 2008). After reviewing the results of those tests and other information submitted by the applicants in the applications, EPA has determined, in accordance with Part 53, that these methods should be designated as equivalent methods. The information submitted by the applicants will be kept on file, either at EPA's National Exposure Research Laboratory, Research Triangle Park, North Carolina 27711 or in an approved archive storage facility, and will be available for inspection (with advance notice) to the extent consistent with 40 CFR Part 2 (EPA's regulations implementing the Freedom of Information Act).

As designated equivalent methods, these methods are acceptable for use by states and other air monitoring agencies under the requirements of 40 CFR Part 58, Ambient Air Quality Surveillance. For such purposes, these methods must be used in strict accordance with the operation or instruction manual associated with the method and subject to any specifications and limitations (e.g., configuration or operational settings) specified in the applicable designated method description (see the identification of the methods above).

Use of these methods also should be in general accordance with the guidance and recommendations of applicable sections of the “Quality Assurance Handbook for Air Pollution Measurement Systems, Volume I,” EPA/600/R-94/038a and “Quality Assurance Handbook for Air Pollution Measurement Systems, Volume II, Ambient Air Quality Monitoring Program” EPA-454/B-08-003, December, 2008. Vendor modifications of designated equivalent methods used for purposes of Part 58 are permitted only with prior approval of the EPA, as provided in Part 53. Provisions concerning modification of such methods by users are specified under Section 2.8 (Modifications of Methods by Users) of Appendix C to 40 CFR Part 58.

In general, a method designation applies to any sampler or analyzer which is identical to the sampler or analyzer described in the application for designation. In some cases, similar samplers or analyzers manufactured prior to the designation may be upgraded or converted (e.g., by minor modification or by substitution of the approved operation or instruction manual) so as to be identical to the designated method and thus achieve designated status. The manufacturer should be consulted to determine the feasibility of such upgrading or conversion.

Part 53 requires that sellers of designated reference or equivalent method analyzers or samplers comply with certain conditions. These conditions are specified in 40 CFR 53.9.

Aside from occasional breakdowns or malfunctions, consistent or repeated noncompliance with any of these conditions should be reported to: Director, Human Exposure and Atmospheric Sciences Division (MD-E205-01), National Exposure Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711.

Designation of these new equivalent methods is intended to assist the States in establishing and operating their air quality surveillance systems under 40 CFR Part 58. Questions concerning the commercial availability or technical aspects of the methods should be directed to the applicants.

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Jewel F. Morris,

Acting Director, National Exposure Research Laboratory.

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[FR Doc. 2010-20476 Filed 8-17-10; 8:45 am]