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Ambient Monitoring Technology Information Center (AMTIC)
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NCore Monitoring Network

On this page:

  • Background
  • Sites and Data

Background

NCore is a multi pollutant network that integrates several advanced measurement systems for particles, pollutant gases and meteorology. Most NCore stations have been operating since the formal start of the network on January 1, 2011.  The requirements for NCore monitoring can be found in 40 CFR part 58 Appendix D.

The NCore Network addresses the following objectives:

  • Timely reporting of data to public by supporting AIRNow, air quality forecasting, and other public reporting mechanisms;
  • Support for development of emission strategies through air quality model evaluation and other observational methods;
  • Accountability of emission strategy progress through tracking long-term trends of criteria and non-criteria pollutants and their precursors;
  • Support for long-term health assessments that contribute to ongoing reviews of the NAAQS;
  • Compliance through establishing nonattainment/attainment areas through comparison with the NAAQS;
  • Support to scientific studies ranging across technological, health, and atmospheric process disciplines; and
  • Support to ecosystem assessments recognizing that national air quality networks benefit ecosystem assessments and, in turn, benefit from data specifically designed to address ecosystem analyses.

Measurements

Parameter Comments
PM2.5 speciation Organic and elemental carbon, major ions and trace metals (24 hour average; every 3rd day); IMPROVE or CSN
PM2.5 FRM mass 24 hr. average at least every 3rd day
continuous PM2.5 mass 1 hour reporting interval; FEM or pre-FEM monitors
PM(10-2.5) mass Filter-based or continuous
ozone (O3) all gases through continuous monitors
carbon monoxide (CO) capable of trace levels (low ppm and below) where needed
sulfur dioxide (SO2) capable of trace levels (low ppb and below) where needed
nitrogen oxide (NO) capable of trace levels (low ppb and below) where needed
total reactive nitrogen (NOy) capable of trace levels (low ppb and below) where needed
surface meteorology wind speed and direction (reported as "Resultant"), temperature, RH
Map of NCore Sites

Sites and Data

The following links can be used to collect information on the number and locations of PM2.5 monitoring sites and to download monitoring data.

  • List of NCore Sites by AQS ID (xlsx)
  • EPA's AirData 
  • EPA's Air Quality System (AQS)
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Last updated on June 21, 2022
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