Federal equivalent method means a method for measuring the concentration of an air pollutant in the ambient air that has been designated as an equivalent method to a Federal Reference Method in accordance with 40 CFR Part 53.
Sources: US EPA. 2013. Technology Transfer Network Ambient Monitoring Technology Information Center - Air Monitoring Methods - Criteria Pollutants. Accessed 11 September 2013. Available at http://www.epa.gov
United States. 2009. Title 40 Code of Federal Regulations Part 52 Approval and Promulgation of Implementation Plans 53.1 -Definitions. Accessed on 11 September 2013. Available at: http://www.ecsr.gov