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

Short answer. Brazil's official air quality index, the IQAr, has five levels, from N1 Boa (0-40) to N5 Péssima (201-400) ¹. The federal environment ministry runs MonitorAr, an air quality app that shows the IQAr by monitoring station; São Paulo state also has CETESB's QUALAR system ²⁷. During wildfire smoke, the Ministry of Health's priority advice is to stay indoors, protected from the smoke ³.

Where can I check air quality in Brazil right now?

Start with MonitorAr, the federal environment ministry's air quality app, which shows the IQAr by monitoring station ². In the State of São Paulo, CETESB's QUALAR system gives station data after registration ⁷. Keep official alerts switched on as well (see our Brazil alerts page).

What do the IQAr levels mean?

The IQAr was set by CONAMA Resolution 491 of 2018 and updated after CONAMA Resolution 506 of 5 July 2024 ¹. The federal environment ministry publishes the current index bands and the matching 24-hour fine-particle (PM2.5) concentrations ¹:

The same table sets bands for PM10, ozone, carbon monoxide, nitrogen dioxide and sulphur dioxide ¹. Phaenyx found no official health advice attached to each level on the ministry's index page. For a general reading of index colours, see air quality index.

How polluted is Brazilian air on average?

Annual fine particles (PM2.5) in the median Brazilian city were about 13 µg/m³ in 2021-2023, against a WHO guideline of 5 µg/m³ ⁴⁶. Nitrogen dioxide (NO2) was about 3.4 µg/m³, under the WHO guideline of 10 µg/m³ ⁵⁶. These are population-weighted medians across 5,440 cities; the NO2 figure is a regional background over roughly 80 km, so a busy street is higher.

What should I do during wildfire smoke?

The Ministry of Health's advice during fires (queimadas) ³:

• Drink more water and fluids to keep your airways moist.
• Stay indoors, preferably in well-sealed rooms with comfortable temperatures; where possible, use places with air conditioning and air filters.
• Keep doors and windows closed when pollution peaks.
• Avoid outdoor exercise during this period.
• Do not eat food, drink or take medicines exposed to burn debris or ash.
• If you must go out, N95, PFF2 or P100 masks can reduce the particles you breathe if worn correctly. Staying indoors comes first.

Children under 5, older people and pregnant women should follow this advice even more closely ³. People with heart, lung or immune conditions should seek care at once if symptoms appear, keep their medicines at hand, and consider leaving the affected area temporarily if it is safe ³.

See wildfire smoke, masks for smoke, clean air room and sensitive people and polluted air. Your household plan can list who is at risk and where your cleaner-air room is.

Frequently asked questions

What IQAr level is bad?

N3 Ruim starts at an index of 81; N4 Muito Ruim at 121 and N5 Péssima at 201 ¹.

Which mask does Brazil's Ministry of Health recommend for smoke?

N95, PFF2 or P100, for people who need to go out; staying indoors is the priority ³.

Who is most at risk from smoke?

Children under 5, older people, pregnant women, and people with heart, lung or immune conditions ³.

Is there one national air quality app?

MonitorAr is the federal environment ministry's app ². São Paulo state also runs CETESB's QUALAR ⁷.