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Ambient Monitoring Technology Information Center (AMTIC)

Chemical Speciation Network Measurements

Chemical Speciation Network (CSN) sites collect aerosol samples over 24 hours on Teflon and nylon filters in the MetOne SASS/SuperSASS sampler and on quartz filters in the URG3000N sampler. Teflon filters are analyzed for 33 elements, nylon filters are analyzed for ions and quartz filters are analyzed for carbon. All Speciation Trend Network (STN) sites operate on a 1-in-3 day sample collection schedule, while the majority of the SLAMS supplemental sites operate on a 1-in-6 day sample collection schedule.

CSN data, including operational parameters (e.g., sample flow rate, sample volume, average ambient temperature, etc.) are reported to EPA’s Air Quality System (AQS). Data can also be retrieved from Air Data.

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