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

Short answer. Chile's environment ministry publishes the day's air condition for 13 zones on Aire Chile, from Santiago to Coyhaique ¹. Critical fine-particle episodes are declared at three levels: Alerta (80-109 µg/m³ of PM2.5 over 24 hours), Preemergencia (110-169) and Emergencia (170 or more) ². On Preemergencia and Emergencia days, the ministry recommends masks for older people, children, pregnant women and the chronically ill ⁴.

Where can I check air quality in Chile right now?

Aire Chile, run by the Ministerio del Medio Ambiente, shows the "Condición del aire" for the day in 13 zones: Región Metropolitana, Valle Central de O'Higgins, Curicó, Talca y Maule, Linares, Chillán y Chillán Viejo, Concepción Metropolitano, Los Ángeles, Temuco y Padre Las Casas, Valdivia, Osorno, Puerto Montt y Puerto Varas, and Coyhaique ¹. It also keeps a monthly register of critical episodes ¹.

These episodes are managed in a set season: from 1 April to 30 September each year, except in the Metropolitana and O'Higgins regions, where it runs from 1 May to 31 August ³. Outside these zones and dates, Phaenyx found no daily public condition on Aire Chile. Year-round, the ministry's national monitoring network, SINCA, maps the stations connected online; fine particles (PM10 and PM2.5) are shown as 24-hour moving averages, updated every hour, and the data are preliminary until validated ⁸.

What do Chile's episode levels mean?

Decree 12 of 2011 sets the PM2.5 standard at 50 µg/m³ over 24 hours and 20 µg/m³ as an annual average ². It defines the levels that trigger environmental emergency situations ²:

The levels can be declared from an air quality forecast ². For a general reading of index levels, see air quality index and pollution episode.

How polluted is Chilean air on average?

Annual fine particles (PM2.5) in the median Chilean city were about 25 µg/m³ in 2021-2023, five times the WHO guideline of 5 µg/m³ ⁵⁷. Nitrogen dioxide (NO2) was about 23.3 µg/m³, above the WHO guideline of 10 µg/m³ ⁶⁷. These are population-weighted medians across 302 cities; the NO2 figure is a regional background over roughly 80 km, so a busy street is higher.

The ministry says air pollution causes respiratory and cardiovascular disease and especially affects people over 65, children under 8, and people with chronic respiratory or heart conditions ³.

What should I do on a bad air day?

The ministry's recommendations ⁴:

• On Preemergencia and Emergencia days, older people, children, pregnant women and the chronically ill should wear masks.
• Do not smoke indoors at home, work or school.
• Do not burn leaves or rubbish.
• Use only dry firewood (under 25% moisture) and never fully close the damper of a wood heater.
• Prefer public transport or car-sharing.

What should I do during wildfire smoke?

The health ministry's advice when there is smoke, ash or fire ⁹:

• Avoid physical activity.
• Close doors and windows, and cover the gap between floor and door with damp cloths.
• Pregnant women, children, older people and people with asthma or COPD should avoid going out or direct exposure to smoke.
• If there is heavy smoke, cover your nose and mouth with a damp cloth.
• Avoid ash on your skin; change and wash clothes with ash on them, and keep children away from ash and debris.
• For difficulty breathing, dizziness or conjunctivitis, call Salud Responde on 600 360 7777 or go to a health centre.

Follow SENAPRED alerts (see our Chile alerts page) and our guides on wildfire smoke, masks for smoke, clean air room and children and polluted air. Your household plan can list who is at risk and where your cleaner-air room is.

Frequently asked questions

What is a Preemergencia ambiental?

The second of three episode levels, declared when 24-hour PM2.5 is 110 to 169 µg/m³ ².

When is the episode season in Santiago?

In the Metropolitana region, 1 May to 31 August ³.

Who should wear a mask on bad air days?

On Preemergencia and Emergencia days: older people, children, pregnant women and the chronically ill ⁴.

What should I do if wildfire smoke reaches my home?

Close doors and windows, avoid physical activity, and keep pregnant women, children, older people and people with asthma or COPD out of the smoke ⁹.

What are the national PM2.5 standards?

50 µg/m³ over 24 hours and 20 µg/m³ as an annual average, under Decree 12 of 2011 ².

Sources

1. Ministerio del Medio Ambiente — Aire Chile – Condición del aire — https://airechile.mma.gob.cl/ (accessed 2026-10-27)
2. Ministerio del Medio Ambiente (Biblioteca del Congreso Nacional, LeyChile) — Decreto 12: Establece norma primaria de calidad ambiental para material particulado fino respirable MP 2,5 — https://www.bcn.cl/leychile/navegar?idNorma=1025202 (accessed 2026-10-27)
3. Ministerio del Medio Ambiente — Aire Chile – Preguntas frecuentes — https://airechile.mma.gob.cl/faq (accessed 2026-10-27)
4. Ministerio del Medio Ambiente — Aire Chile – Recomendaciones — https://airechile.mma.gob.cl/recomendaciones (accessed 2026-10-27)
5. Atmospheric Composition Analysis Group (ACAG), Washington University in St. Louis — Surface PM2.5, V6.GL.02.04 — https://sites.wustl.edu/acag/datasets/surface-pm2-5/ (accessed 2026-10-27)
6. Copernicus Atmosphere Monitoring Service — CAMS global reanalysis (EAC4) — https://ads.atmosphere.copernicus.eu/ (accessed 2026-10-27)
7. World Health Organization — WHO global air quality guidelines — https://www.who.int/publications/i/item/9789240034228 (accessed 2026-10-27)
8. Ministerio del Medio Ambiente — SINCA – Sistema de Información Nacional de Calidad del Aire, archived copy of 8 Oct. 2026 — http://web.archive.org/web/20261008120534/https://sinca.mma.gob.cl/ (accessed 2026-10-27)
9. Ministerio de Salud (MINSAL) — Prevención de incendios forestales (1 October 2024), archived copy of 7 Oct. 2025 — http://web.archive.org/web/20251007054153/https://www.minsal.cl/campana-verano-2024-2025-prevencion-de-incendios-forestales/ (accessed 2026-10-27)