SmogRank / World / South Korea / Chungcheongnam-do / September 2026

Most polluted cities in Chungcheongnam-do, South Korea, September 2026

13 cities in Chungcheongnam-do, South Korea ranked by their average PM2.5 over the 30 days. Worst: Seonghwan at 15.9 µg/m³, #350 of 2,949 cities in the world. Cleanest: Gongju at 8.8. A city needs measurements on 70% of the days to be ranked.

Ranked by unhealthy days: the share of each city's measured days with a daily mean over 35.4 µg/m³ (US AQI 101+), Unhealthy for Sensitive Groups or worse on the US EPA's scale. Ties go to the higher average.

← Seonghwan 0% 0.75%0
Every city in Chungcheongnam-do, South Korea ranked for September 2026, one column each, ranked by unhealthy days: height is the share of its measured days that were unhealthy, colour its average. Point at it to read a city; tap to open it.
  1. 1Seonghwan
    0%
  2. 2Yesan
    0%
  3. 3Hongseong
    0%
  4. 4Tangjin
    0%
  5. 5Yŏnmu
    0%
  6. 6Boryeong
    0%
  7. 7Cheonan
    0%
  8. 8Asan
    0%
  9. 9Nonsan
    0%
  10. 10Seosan
    0%
  11. 11Taesal-li
    0%
  12. 12Buyeo
    0%
  13. 13Gongju
    0%
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

All cities in the world, September 2026 · All cities in South Korea, September 2026 · Chungcheongnam-do now

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SmogRank, most polluted cities in Chungcheongnam-do, South Korea, PM2.5, September 2026, smogrank.com/kr/region/chungcheongnam-do/history/2026-09 (accessed 6 Oct 2026).

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