Ambient Air Monitoring Reference and Equivalent Methods; Designation of One New Equivalent Method

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Notice of the designation of a new equivalent method for monitoring ambient air quality.

SUMMARY:

Notice is hereby given that the Environmental Protection Agency (EPA) has designated one new equivalent method for measuring concentrations of ozone (O₃) in ambient air.

FOR FURTHER INFORMATION CONTACT:

Robert Vanderpool, Air Methods and Characterization Division (MD-D205-03), Center for Environmental Measurement and Modeling, U.S. EPA, Research Triangle Park, North Carolina 27711. Phone: 919-541-7877. email address: Vanderpool.Robert@epa.gov.

SUPPLEMENTARY INFORMATION:

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 (NAAQS). Monitoring methods that are determined to meet specific requirements for adequacy are designated by the EPA as either reference or equivalent methods (as applicable), thereby permitting their use under 40 CFR part 58 by States and other agencies for determining compliance with the NAAQS. A list of all reference or equivalent methods that have been previously designated by EPA may be found at http://www.epa.gov/ttn/amtic/criteria.html.

The EPA hereby announces the designation of one new equivalent method for measuring concentrations of O₃ in ambient air. This designation is made under the provisions of 40 CFR part 53, as amended on October 26, 2015 (80 FR 65292).

This new equivalent method for O₃ is an automated method (analyzer) utilizing the measurement principle based on UV photometry. This newly designated equivalent method is identified as follows:

EQOA-0424-263, “Vasthi Instruments Model Vair-9004 O₃ Analyzer,” UV photometric analyzer operated in a range of 0-0.5 ppm, with 0.5 µm, 47 mm diameter Teflon® filter installed, operated at temperatures between 20 °C and 30 °C, with temperature and pressure compensation, at a nominal sampling flow rate of 800 cc/min, using a 5 minute averaging time, with either 105VAC-125VAC or 200VAC-240VAC input power options, 270-watt power consumption, equipped with 7 inch LCD touch screen display, and operated according to the Vasthi Instruments Model Vair-9004 Ozone Analyzer User's Instruction Manual.

This application for an equivalent method determination for this O₃ method was received by the Office of Research and Development on April 8, 2024. This analyzer is commercially available from the applicant, Vasthi Instruments, Guntur 522 001, Andhra Pradesh, India.

A representative test analyzer was tested in accordance with the applicable test procedures specified in 40 CFR part 53, as amended on October 26, 2015. After reviewing the results of those tests and other information submitted by the applicant, EPA has determined, in accordance with 40 CFR part 53, that this method should be designated as an equivalent method.

As a designated equivalent method, this method is 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, this method 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 designated method description (see the identification of the method above).

Use of the method 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-13-003, (both available at http://www.epa.gov/ttn/amtic/qalist.html ). 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.

Consistent or repeated noncompliance with any of these conditions should be reported to: Director, Air Methods and Characterization Division (MD-D205-03), Center for Environmental Measurement and Modeling, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711.

Designation of this equivalent method 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 method should be directed to the applicant.