Air pollution
Fine dust (PM2.5) builds up over Bangkok most years between January and March. In January 2025 it closed hundreds of schools. Readings in the orange or red band harm health, especially for people with asthma or heart conditions.
There is no alert for this at the moment
This is guidance to read before you need it.
Do this now
- Check the current reading for Phra Nakhon on Air4Thai before you go out.
- Outdoors, wear a well-fitting N95 or KN95 mask. A loose cloth mask does not stop fine dust.
- Keep windows closed and spend time in air-conditioned or filtered rooms.
- Cut down on running, cycling and other hard exercise outdoors.
- If you have asthma, keep your reliever inhaler with you and follow your action plan.
Call
What the colours mean
Thailand reports PM2.5 as a 24-hour average in micrograms per cubic metre. The national standard is 37.5.
- Blue, 0 to 15, very good.
- Green, 15.1 to 25, good.
- Yellow, 25.1 to 37.5, moderate. People with lung or heart conditions should take care.
- Orange, 37.6 to 75, starting to affect health. Everyone should limit time outdoors and wear a mask outside.
- Red, above 75, affecting health. Avoid going outside where you can. Wear a mask outdoors, and consider one indoors if the air is not filtered.
Masks
- An N95 or KN95 mask protects you only if it seals around your nose and chin. Pinch the metal strip to fit your nose.
- Replace a mask when it gets damp, dirty or hard to breathe through.
- The Department of Health warns that people with severe lung or heart disease may struggle to breathe through an N95. Ask a doctor which mask suits you.
When to get help
- Sore eyes, a scratchy throat and a cough are common on bad days. Rinse your eyes and nose with saline and drink water.
- Go to the TU Virtual Clinic or a doctor if a cough will not go away or your asthma is getting worse.
- Call 1669 at once for chest pain, severe breathlessness or wheezing that your inhaler does not relieve.
Classes
On the worst days the university or faculty may move teaching online or ask people to work from home. Check your Thammasat email and course pages the evening before.
Contacts
Air4Thai, official air quality readings
Pollution Control Department. Also an app.
Ambulance and medical emergency
24 hours, free
TU Virtual Clinic, Tha Prachan
Weekdays 08:30 to 16:30, closed on public holidays. Ground floor of the Student Activities Centre (Building 21).
Department of Disease Control hotline
Advice on infectious diseases and outbreaks.
Faculty of Political Science office
Weekdays 09:00 to 16:00. Email polscitu@tu.ac.th.