{
  "Header": [
    {
      "status": "Success",
      "request_time": "2026-04-15T19:33:06-04:00",
      "url": "https://aqs.epa.gov/data/api/list/classes?email=test%40aqs.api&key=test",
      "rows": 27
    }
  ],
  "Data": [
    {
      "code": "AIRNOW MAPS",
      "value_represented": "The parameters represented on AirNow maps (88101, 88502, and 44201)"
    },
    {
      "code": "ALL",
      "value_represented": "Select all Parameters Available"
    },
    {
      "code": "AQI POLLUTANTS",
      "value_represented": "Pollutants that have an AQI Defined"
    },
    {
      "code": "CORE_HAPS",
      "value_represented": "Urban Air Toxic Pollutants"
    },
    {
      "code": "CRITERIA",
      "value_represented": "Criteria Pollutants"
    },
    {
      "code": "CSN DART",
      "value_represented": "List of CSN speciation parameters to populate the STI DART tool"
    },
    {
      "code": "FORECAST",
      "value_represented": "Parameters routinely extracted by AirNow (STI)"
    },
    {
      "code": "HAPS",
      "value_represented": "Hazardous Air Pollutants"
    },
    {
      "code": "IMPROVE CARBON",
      "value_represented": "IMPROVE Carbon Parameters"
    },
    {
      "code": "IMPROVE_SPECIATION",
      "value_represented": "PM2.5 Speciated Parameters Measured at IMPROVE sites"
    },
    {
      "code": "MET",
      "value_represented": "Meteorological Parameters"
    },
    {
      "code": "NATTS CORE HAPS",
      "value_represented": "The core list of toxics of interest to the NATTS program."
    },
    {
      "code": "NATTS REQUIRED",
      "value_represented": "Required compounds to be collected in the National Air Toxics Network"
    },
    {
      "code": "PAMS",
      "value_represented": "Photochemical Assessment Monitoring System"
    },
    {
      "code": "PAMS_VOC",
      "value_represented": "Volatile Organic Compound subset of the PAMS Parameters"
    },
    {
      "code": "PM COARSE",
      "value_represented": "PM between 2.5 and 10 micrometers"
    },
    {
      "code": "PM10 SPECIATION",
      "value_represented": "PM10 Speciated Parameters"
    },
    {
      "code": "PM2.5 CONT NONREF",
      "value_represented": "PM2.5 Continuous, Nonreference Methods"
    },
    {
      "code": "PM2.5 MASS/QA",
      "value_represented": "PM2.5 Mass and QA Parameters"
    },
    {
      "code": "SCHOOL AIR TOXICS",
      "value_represented": "School Air Toxics Program Parameters"
    },
    {
      "code": "SPECIATION",
      "value_represented": "PM2.5 Speciated Parameters"
    },
    {
      "code": "SPECIATION CARBON",
      "value_represented": "PM2.5 Speciation Carbon Parameters"
    },
    {
      "code": "SPECIATION CATION/ANION",
      "value_represented": "PM2.5 Speciation Cation/Anion Parameters"
    },
    {
      "code": "SPECIATION METALS",
      "value_represented": "PM2.5 Speciation Metal Parameters"
    },
    {
      "code": "UATMP CARBONYL",
      "value_represented": "Urban Air Toxics Monitoring Program Carbonyls"
    },
    {
      "code": "UATMP VOC",
      "value_represented": "Urban Air Toxics Monitoring Program VOCs"
    },
    {
      "code": "VOC",
      "value_represented": "Volatile organic compounds"
    }
  ]
}