SmogRank / South Korea / Chungcheongnam-do

Air quality in Seosan

Chungcheongnam-do, South Korea. PM2.5 from 3 reference monitors, updated hourly.

2China AQI
Excellent

Latest hour (03:00 UTC), 0.1× the WHO 24-hour guideline. PM2.5 1.0 µg/m³.

Rank, worst first

24 hours–not enough data
7 days#842of 2,605, at 14 China AQI (9.6 µg/m³)
30 days#4of 2,626, at 275 China AQI (224.6 µg/m³)
This year#7of 2,447, at 172 China AQI (130.2 µg/m³)

The last 12 months, day by day

1102031Nov 2025DecJan 2026FebMarAprMayJunJulAugSepOct2025-11-01: no data2025-11-02: no data2025-11-03: no data2025-11-04: no data2025-11-05: no data2025-11-06: no data2025-11-07: no data2025-11-08: no data2025-11-09: no data2025-11-10: no data2025-11-11: no data2025-11-12: no data2025-11-13: no data2025-11-14: no data2025-11-15: no data2025-11-16: no data2025-11-17: no data2025-11-18: no data2025-11-19: no data2025-11-20: no data2025-11-21: no data2025-11-22: no data2025-11-23: no data2025-11-24: no data2025-11-25: no data2025-11-26: no data2025-11-27: no data2025-11-28: no data2025-11-29: no data2025-11-30: no data2025-12-01: no data2025-12-02: no data2025-12-03: no data2025-12-04: no data2025-12-05: no data2025-12-06: no data2025-12-07: no data2025-12-08: no data2025-12-09: no data2025-12-10: no data2025-12-11: no data2025-12-12: no data2025-12-13: no data2025-12-14: no data2025-12-15: no data2025-12-16: no data2025-12-17: no data2025-12-18: no data2025-12-19: no data2025-12-20: no data2025-12-21: no data2025-12-22: no data2025-12-23: no data2025-12-24: no data2025-12-25: no data2025-12-26: no data2025-12-27: no data2025-12-28: no data2025-12-29: no data2025-12-30: no data2025-12-31: no data2026-01-01: no data2026-01-02: no data2026-01-03: no data2026-01-04: no data2026-01-05: no data2026-01-06: no data2026-01-07: no data2026-01-08: no data2026-01-09: no data2026-01-10: no data2026-01-11: no data2026-01-12: no data2026-01-13: no data2026-01-14: no data2026-01-15: no data2026-01-16: no data2026-01-17: no data2026-01-18: no data2026-01-19: no data2026-01-20: no data2026-01-21: no data2026-01-22: no data2026-01-23: no data2026-01-24: no data2026-01-25: no data2026-01-26: no data2026-01-27: no data2026-01-28: no data2026-01-29: no data2026-01-30: no data2026-01-31: no data2026-02-01: no data2026-02-02: no data2026-02-03: no data2026-02-04: no data2026-02-05: no data2026-02-06: no data2026-02-07: no data2026-02-08: no data2026-02-09: no data2026-02-10: no data2026-02-11: no data2026-02-12: no data2026-02-13: no data2026-02-14: no data2026-02-15: no data2026-02-16: no data2026-02-17: no data2026-02-18: no data2026-02-19: no data2026-02-20: no data2026-02-21: no data2026-02-22: no data2026-02-23: no data2026-02-24: no data2026-02-25: no data2026-02-26: no data2026-02-27: no data2026-02-28: no data2026-03-01: no data2026-03-02: no data2026-03-03: no data2026-03-04: no data2026-03-05: no data2026-03-06: no data2026-03-07: no data2026-03-08: no data2026-03-09: no data2026-03-10: no data2026-03-11: no data2026-03-12: no data2026-03-13: no data2026-03-14: no data2026-03-15: no data2026-03-16: no data2026-03-17: no data2026-03-18: no data2026-03-19: no data2026-03-20: no data2026-03-21: no data2026-03-22: no data2026-03-23: no data2026-03-24: no data2026-03-25: no data2026-03-26: no data2026-03-27: no data2026-03-28: no data2026-03-29: no data2026-03-30: no data2026-03-31: no data2026-04-01: no data2026-04-02: no data2026-04-03: no data2026-04-04: no data2026-04-05: no data2026-04-06: no data2026-04-07: no data2026-04-08: no data2026-04-09: no data2026-04-10: no data2026-04-11: no data2026-04-12: no data2026-04-13: no data2026-04-14: no data2026-04-15: no data2026-04-16: no data2026-04-17: no data2026-04-18: no data2026-04-19: no data2026-04-20: no data2026-04-21: no data2026-04-22: no data2026-04-23: no data2026-04-24: no data2026-04-25: no data2026-04-26: no data2026-04-27: no data2026-04-28: no data2026-04-29: no data2026-04-30: no data2026-05-01: no data2026-05-02: no data2026-05-03: no data2026-05-04: no data2026-05-05: no data2026-05-06: no data2026-05-07: no data2026-05-08: no data2026-05-09: no data2026-05-10: no data2026-05-11: no data2026-05-12: no data2026-05-13: no data2026-05-14: no data2026-05-15: no data2026-05-16: no data2026-05-17: no data2026-05-18: no data2026-05-19: no data2026-05-20: no data2026-05-21: no data2026-05-22: no data2026-05-23: no data2026-05-24: no data2026-05-25: no data2026-05-26: no data2026-05-27: no data2026-05-28: no data2026-05-29: no data2026-05-30: no data2026-05-31: no data2026-06-01: no data2026-06-02: no data2026-06-03: no data2026-06-04: no data2026-06-05: no data2026-06-06: no data2026-06-07: no data2026-06-08: no data2026-06-09: no data2026-06-10: no data2026-06-11: no data2026-06-12: no data2026-06-13: no data2026-06-14: no data2026-06-15: no data2026-06-16: no data2026-06-17: no data2026-06-18: no data2026-06-19: no data2026-06-20: no data2026-06-21: no data2026-06-22: no data2026-06-23: no data2026-06-24: no data2026-06-25: no data2026-06-26: no data2026-06-27: no data2026-06-28: no data2026-06-29: no data2026-06-30: no data2026-07-01: no data2026-07-02: no data2026-07-03: no data2026-07-04: no data2026-07-05: no data2026-07-06: no data2026-07-07: no data2026-07-08: no data2026-07-09: no data2026-07-10: no data2026-07-11: no data2026-07-12: no data2026-07-13: no data2026-07-14: no data2026-07-15: no data2026-07-16: no data2026-07-17: no data2026-07-18: no data2026-07-19: no data2026-07-20: no data2026-07-21: no data2026-07-22: no data2026-07-23: no data2026-07-24: no data2026-07-25: no data2026-07-26: no data2026-07-27: no data2026-07-28: no data2026-07-29: no data2026-07-30: no data2026-07-31: no data2026-08-01: no data2026-08-02: no data2026-08-03: no data2026-08-04: no data2026-08-05: no data2026-08-06: no data2026-08-07: no data2026-08-08: no data2026-08-09: no data2026-08-10: no data2026-08-11: no data2026-08-12: no data2026-08-13: no data2026-08-14: no data2026-08-15: no data2026-08-16: no data2026-08-17: no data2026-08-18: no data2026-08-19: no data2026-08-20: no data2026-08-21: no data2026-08-22: no data2026-08-23: no data2026-08-24: no data2026-08-25: no data2026-08-26: no data2026-08-27: no data2026-08-28: no data2026-08-29: no data2026-08-30: no data2026-08-31: no data2026-09-01: no data2026-09-02: no data2026-09-03: no data2026-09-04: no data2026-09-05: no data2026-09-06: no data2026-09-07: no data2026-09-08: no data2026-09-09: no data2026-09-10: no data2026-09-11: no data2026-09-12: no data2026-09-13: no data2026-09-14: no data2026-09-15: no data2026-09-16: no data2026-09-17: no data2026-09-18: no data2026-09-19: no data2026-09-20: no data2026-09-21: no data2026-09-22: no data2026-09-23: no data2026-09-24: no data2026-09-25: no data2026-09-26: no data2026-09-27: no data2026-09-28: no data2026-09-29: no data2026-09-30: no data2026-10-01: no data
Daily history appears as days complete. One row per month, one square per local day.
Excellent0–50
Good51–100
Lightly polluted101–150
Moderately polluted151–200
Heavily polluted201–300
Severely polluted301+

China's Air Quality Index (HJ 633-2012), PM2.5 individual index. Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

Last 4 days, hour by hour

15302026-10-02 00:00 UTC: 23.0 µg/m³2026-10-02 01:00 UTC: 20.0 µg/m³2026-10-02 02:00 UTC: 4.0 µg/m³2026-10-02 03:00 UTC: 1.0 µg/m³Sep 29Sep 30Oct 1
Times in UTC. Dashed line: WHO 24-hour guideline (15 µg/m³).

Monitors

StationOperatorType
성연면Permission requested (AirKorea, 2026-10-01)Korea Air Ministry of EnvironmentReference
동문동Permission requested (AirKorea, 2026-10-01)Korea Air Ministry of EnvironmentReference
동문동Permission requested (AirKorea, 2026-10-01)Korea Air Ministry of EnvironmentReference

The city's value is the median of its reference monitors each hour, when at least a third of them report (three are always enough); low-cost sensors are listed but not counted when reference monitors exist. Data via OpenAQ; licences as listed. How we rank. Embed this on your site.

Other cities in South Korea

30-day averages, China AQI. All of South Korea.

Updated 2026-10-02 04:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the China AQI PM2.5 sub-index.