Air quality in Taiwan: where to check and what to do

Short answer. Check the Ministry of Environment's (MOENV) Taiwan Air Quality Monitoring Network, which publishes a real-time Air Quality Index (AQI) as a reference for early warnings, with hourly monitoring data ¹. The AQI runs from 0 to 500 in six levels, from "good" to "hazardous" ¹. At "very unhealthy" (201-300) MOENV says everyone should reduce outdoor activities; above 300, avoid them and keep doors and windows closed ¹.

Where can I check air quality right now?

On the Taiwan Air Quality Monitoring Network (airtw.moenv.gov.tw), in English and Chinese ¹². Each station's real-time AQI is the highest of its sub-indices for ozone, PM2.5, PM10, carbon monoxide, sulphur dioxide and nitrogen dioxide, and that pollutant is named as the leading pollutant ¹.

What do the index levels mean?

MOENV attaches advice for the general public and for sensitive groups to each level ¹²:

For people with heart, respiratory or cardiovascular disease, children, teenagers and older adults, MOENV advises reducing exertion and outdoor activities from 101-150 (wearing a mask if they must go out ²), staying indoors from 151-200, and staying indoors and avoiding exertion above 300; people with asthma may need their reliever inhalers more often ¹. See Air quality index explained.

How polluted is the air on average?

The population-weighted median of Taiwanese cities shows about 18 µg/m³ of PM2.5 (annual mean 2021-2023) ³, more than three times the WHO guideline of 5 µg/m³ ⁵. Nitrogen dioxide is about 20.5 µg/m³ ⁴, about twice the WHO guideline of 10 µg/m³ ⁵. That NO2 figure is a regional background over roughly 80 km: a busy street will be higher. These are city medians: a given town can be cleaner or more polluted.

What should I do on a bad air day, or with smoke or dust?

• Bad air days: follow the MOENV advice above, and see Pollution episodes, Sensitive people and polluted air and Children and polluted air.
• Ozone: see Ozone days.
• Smoke: see Wildfire smoke, A clean-air room at home and Masks for smoke.
• Dust: see Dust storms.

For official warnings in Taiwan, see our Taiwan alerts page. A household plan can list who in your home is sensitive to polluted air and where to shelter.

Frequently asked questions

What sets the AQI at a station?

The pollutant with the highest sub-index, named as the leading pollutant; the real-time AQI is published with hourly data ¹.

When should children stop playing outside in Taiwan?

MOENV says students should stop outdoor activities and move classes indoors from "very unhealthy" (201-300) ¹.

Should I wear a mask on bad air days?

MOENV's Chinese table advises sensitive groups to wear a mask if they must go out from 101 upwards ², and the general public from 301 ¹. See Masks for smoke.

Is Taiwan's air above WHO guidelines?

Yes, on average: about 18 µg/m³ of PM2.5 and 20.5 µg/m³ of regional NO2, against guidelines of 5 and 10 µg/m³ ³⁴⁵.

Sources

1. 環境部 Ministry of Environment (MOENV) — Air Quality Index - Taiwan Air Quality Monitoring Network — https://airtw.moenv.gov.tw/ENG/Information/Standard/AirQualityIndicator.aspx (accessed 2026-10-27)
2. 環境部 Ministry of Environment (MOENV) — 空氣品質指標 - 空氣品質監測網 — https://airtw.moenv.gov.tw/CHT/Information/Standard/AirQualityIndicator.aspx (accessed 2026-10-27)
3. Atmospheric Composition Analysis Group (ACAG), Washington University in St. Louis — Surface PM2.5, V6.GL.02.04 (annual mean 2021-2023) — https://sites.wustl.edu/acag/datasets/surface-pm2-5/ (accessed 2026-10-27)
4. Copernicus Atmosphere Monitoring Service (CAMS) — CAMS global reanalysis (EAC4) — https://ads.atmosphere.copernicus.eu/ (accessed 2026-10-27)
5. World Health Organization (WHO) — WHO global air quality guidelines (2021) — https://www.who.int/publications/i/item/9789240034228 (accessed 2026-10-27)