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

Short answer. The National Environment Agency (NEA) publishes Singapore's air quality on haze.gov.sg for five regions: north, south, east, west and central ¹. Use the 1-hour PM2.5 reading for what you do in the next hour, and the 24-hour PSI forecast with its health advisory for the next day ². In Band 3 (151-250 µg/m³), healthy people should avoid strenuous outdoor activity; vulnerable people should avoid all outdoor activity ².

Where can I check air quality right now?

On haze.gov.sg, NEA shows the current 1-hour PM2.5 reading and the 24-hour Pollutant Standards Index (PSI) for the north, south, east, west and central regions, with pollutant sub-indices, satellite hotspots and a regional haze outlook ¹. NEA also points to its website nea.gov.sg and the myENV mobile app for current readings ².

What do the index levels mean?

Singapore has two official scales ¹².

1-hour PM2.5 bands (for the next hour):

24-hour PSI (for next-day planning): 0-100 is "Good to Moderate", 101-200 "Unhealthy", 201-300 "Very Unhealthy" and above 300 "Hazardous" ¹².

NEA defines vulnerable persons as the elderly, pregnant women, children, and people with chronic lung or heart disease ². See Air quality index explained.

How polluted is the air on average?

The population-weighted median of Singapore's locations shows about 14 µg/m³ of PM2.5 (annual mean 2021-2023) ⁴, close to three times the WHO guideline of 5 µg/m³ ⁶. Nitrogen dioxide is about 8.9 µg/m³ ⁵, below the WHO guideline of 10 µg/m³ ⁶. That NO2 figure is a regional background over roughly 80 km: a busy street will be higher.

What should I do during haze or on a bad air day?

• Check before you go out. NEA advises looking at the latest 1-hour PM2.5 reading before outdoor activities in the next few hours, and at the PSI forecast and health advisory for the next day ².
• On an "Unhealthy" PSI forecast (101-200): healthy people should reduce prolonged or strenuous outdoor exertion; the elderly, pregnant women and children should minimise it; people with chronic lung or heart disease should avoid it ².
• Above 300 (Hazardous): healthy people should minimise outdoor activities; vulnerable groups should avoid them ².
• Feeling unwell: NEA says people who are not feeling well should seek medical attention ².
• Masks: SCDF lists an N95 mask among the essential items of its Ready Bag, to protect against excessive exposure to pollutants ³. See Masks for smoke.

Haze in Singapore comes from fires in the wider region: NEA's daily update tracks hotspots and smoke haze across the southern ASEAN region and warns of the risk of transboundary haze ¹. See Wildfire smoke, A clean-air room at home and Sensitive people and polluted air. How official warnings reach you is on our Singapore alerts page.

A household plan can note who at home is vulnerable to haze and keep masks with your supplies.

Frequently asked questions

Should I use the PSI or PM2.5 to decide whether to go out?

For the next hour, the 1-hour PM2.5 reading; for the next day, the PSI forecast and health advisory ².

At what level should children stay indoors?

NEA's PSI advisory tells children to minimise prolonged or strenuous outdoor exertion at 101-200, to minimise outdoor activities at 201-300 and to avoid them above 300 ².

Is there an app?

Yes. NEA points to its myENV mobile app for current readings ².

Where does the haze come from?

From fires and hotspots in the region, tracked in NEA's daily haze update ¹.

Sources

1. National Environment Agency (NEA) — Haze – Latest Update, 1-hr PM2.5 readings and 24-hr PSI — https://www.haze.gov.sg/ (accessed 2026-10-27)
2. National Environment Agency (NEA) — How to plan your outdoor activities during haze (PM2.5 and PSI guide, October 2026) — https://www.haze.gov.sg/docs/default-source/posters/haze-pm-psi-guide-a4-yoca-english_18-oct.pdf (accessed 2026-10-27)
3. Singapore Civil Defence Force (SCDF) — Civil Defence Emergency Handbook (10th edition, 2026) – English — https://www.scdf.gov.sg/docs/default-source/comm.---volunteers-(docs)/2026-scdf-emergency-handbook(eng)_16-oct.pdf (accessed 2026-10-27)
4. 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)
5. Copernicus Atmosphere Monitoring Service (CAMS) — CAMS global reanalysis (EAC4) — https://ads.atmosphere.copernicus.eu/ (accessed 2026-10-27)
6. World Health Organization (WHO) — WHO global air quality guidelines (2021) — https://www.who.int/publications/i/item/9789240034228 (accessed 2026-10-27)