RSQA - air quality index (historical)

The City of Montreal measures air quality in the form of a numerical value called the “Air Quality Index (AQI).” This data set provides access to historical AQI values, updated daily.

*Note: The AQI systems do not change the time: they always use Eastern Standard Time (EST) and not Eastern Daylight Time (EDT). So during daylight savings time, there is a 1-hour time lag in the data. For example, a measurement recorded at 12 pm EST is that of 1 pm EDT. *

The daily values, updated every hour, are available [here] (rsqa-air-quality-index).

The [list of stations] (rsqa-liste-des-stations) and [sectors] (rsqa-geographic-sectors) linked to RSQA data is also available.

Data and Resources

Additional Info

Field Value
Last Updated April 17, 2026, 18:53 (UTC)
Created April 17, 2026, 18:53 (UTC)
contact_email donneesouvertes@montreal.ca
contact_person {"en": "Ville de Montréal", "fr": "Ville de Montréal"}
criticality_level []
data_dictionary ["environment"]
geographic_scope []
open_canada_collection federated
open_canada_date_published 2021-06-10 00:00:00
open_canada_keywords {"en-t-fr": ["IQA", "Pollution", "Air quality", "RSQA", "SeNV"], "fr": ["IQA", "Pollution", "Qualité de l air", "RSQA", "SEnv"]}
open_canada_subject ["nature_and_environment"]
sensitivity_level unrestricted
title_fr RSQA - indice de la qualité de l'air (historique)
update_frequency P1D