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What does the POC number refer to?

POC is the Parameter Occurrence Code and is used to uniquely identify a monitor if there is more than one device measuring the same pollutant at a site. The POC number assignment is somewhat arbitrary and varies between sites that are maintained by different state and local agencies. POC designation and monitor type are independent of each other.

Return to Frequent Questions about AirData

Related Questions

  • What is the difference between parameter codes 88101 and 88502 for PM2.5 monitors?
  • What is an exceptional event?
  • Does the ‘exclude exceptional events’ option exclude only EPA regionally-concurred exceptional events or all flagged events?

Outdoor Air Quality Data

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Last updated on August 16, 2024
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