[
  {
    "obs_id": "O900",
    "station_raw": "A측정소(구)",
    "station_id": null,
    "pollutant": "PM2.5",
    "value": null,
    "limit": 50,
    "measured_at": "2026-05-20T09:00:00"
  },
  {
    "obs_id": "O901",
    "station_id": "stn0",
    "station_raw": "측정소0",
    "pollutant": "NOx",
    "value": -5,
    "limit": 100,
    "measured_at": "2026-05-20T09:00:00"
  },
  {
    "obs_id": "O902",
    "station_raw": "초과측정소",
    "station_id": "stn2",
    "pollutant": "SOx",
    "value": 500,
    "limit": 100,
    "measured_at": "2026-05-20T03:00:00"
  },
  {
    "obs_id": "O903",
    "station_raw": "미등록측정소",
    "station_id": null,
    "pollutant": "PM2.5",
    "value": 30,
    "limit": 50,
    "measured_at": "1970-01-01T00:00:00"
  },
  {
    "obs_id": "O000",
    "station_raw": "측정소0",
    "station_id": "stn0",
    "pollutant": "PM2.5",
    "value": 20,
    "limit": 100,
    "measured_at": "2026-05-20T09:00:00"
  },
  {
    "obs_id": "O001",
    "station_raw": "측정소1",
    "station_id": "stn1",
    "pollutant": "NOx",
    "value": 23.5,
    "limit": 100,
    "measured_at": "2026-05-20T09:00:00"
  },
  {
    "obs_id": "O002",
    "station_raw": "측정소2",
    "station_id": "stn2",
    "pollutant": "SOx",
    "value": 27,
    "limit": 100,
    "measured_at": "2026-05-20T09:00:00"
  },
  {
    "obs_id": "O003",
    "station_raw": "측정소3",
    "station_id": "stn3",
    "pollutant": "PM2.5",
    "value": 30.5,
    "limit": 100,
    "measured_at": "2026-05-20T09:00:00"
  },
  {
    "obs_id": "O004",
    "station_raw": "측정소4",
    "station_id": "stn4",
    "pollutant": "NOx",
    "value": 34,
    "limit": 100,
    "measured_at": "2026-05-20T09:00:00"
  },
  {
    "obs_id": "O005",
    "station_raw": "측정소0",
    "station_id": "stn0",
    "pollutant": "SOx",
    "value": 37.5,
    "limit": 100,
    "measured_at": "2026-05-20T09:00:00"
  },
  {
    "obs_id": "O006",
    "station_raw": "측정소1",
    "station_id": "stn1",
    "pollutant": "PM2.5",
    "value": 41,
    "limit": 100,
    "measured_at": "2026-05-20T09:00:00"
  },
  {
    "obs_id": "O007",
    "station_raw": "측정소2",
    "station_id": "stn2",
    "pollutant": "NOx",
    "value": 44.5,
    "limit": 100,
    "measured_at": "2026-05-20T09:00:00"
  }
]