Air quality in Saint-Étienne, Auvergne-Rhône-Alpes, France today

Mr. Duck’s Air Quality Score

Good air today for Saint-Étienne, Auvergne-Rhône-Alpes, France

⚠️ This website is currently under active development. Some data may be incomplete or temporarily inaccurate. For health-critical decisions, please verify information through official government or environmental sources.

Categories follow US EPA AQI breakpoints for PM (estimate from latest valid measurements; this project does not compute EPA NowCast/24-hour AQI yet).

This friendly indicator summarizes the latest city readings. For health guidance, please see: EPA AirNow or WHO.

Air quality today

The air quality in Saint‑Étienne today falls into the Good category. The primary pollutant identified is PM2.5, with a measured reference value of 0.8 µg/m³, while PM10 shows a reference value of 1.6 µg/m³ based on six valid observations.

Data are shown via OpenAQ and reflect the current monitoring results for the city. This page is informational; for health guidance, use official sources such as EPA AirNow or WHO.

Latest sensor values

PM categories follow US EPA AQI breakpoints, shown here as an estimate derived from the latest valid measurements (this project does not compute EPA NowCast/24-hour AQI yet).

What the data includes

The dataset for Saint‑Étienne includes six measured pollutants – nitrogen monoxide (NO), nitrogen dioxide (NO₂), ozone (O₃), particulate matter ≤ 10 µm (PM10), particulate matter ≤ 2.5 µm (PM2.5) and sulphur dioxide (SO₂). It is compiled from twelve individual rows that come from three monitoring stations, all located at the SAINT ETIENNE SUD site.

Most of the recent observations were recorded within the last three days. NO₂, PM10, PM2.5 and O₃ each have a latest timestamp of 2026‑02‑10 15:00 UTC, showing that their values are up‑to‑date. By contrast, NO’s newest entry dates back to 2024‑03‑11 09:00 UTC and is flagged as “old data”, while SO₂ has not been updated since 2016‑12‑05 01:00 UTC, indicating a long gap in coverage for these two gases.

The measured concentrations span a wide range. NO₂ values range from a minimum of 8.4 µg/m³ to a maximum of 65.63 µg/m³, with a median around 30.9 µg/m³; the 10th and 90th percentiles (12.9 µg/m³ and 58.68 µg/m³) show that most readings sit between low‑double‑digit levels. PM10 varies from 1.6 to 10.6 µg/m³, median 9.4 µg/m³, while PM2.5 is much lower, ranging from 0.8 to 6.05 µg/m³ with a median of 3.43 µg/m³. O₃ is constant at 63.6 µg/m³ across the recent data set, and SO₂ registers only zeros in its historic record.

Overall, the dataset provides fresh information for most pollutants but shows uneven temporal coverage: NO and especially SO₂ rely on older measurements, so current conditions for these gases may not be fully represented. Users should keep in mind that air quality can differ across neighbourhoods and times, and the available rows reflect only the SAINT ETIENNE SUD monitoring point.

Learn more about sources and filtering: About the data.

Trusted references: WHO (Air pollution) · US EPA AirNow · European Environment Agency (Air)

Latest sensor values (bars)

PM categories follow US EPA AQI breakpoints, shown here as an estimate derived from the latest valid measurements (this project does not compute EPA NowCast/24-hour AQI yet).

Data notes

The data shown reflect six valid measurements and are “Updated within 3 days,” with the most recent reading recorded on 2026‑02‑10 at 15:00 UTC. This snapshot provides a brief overview of current conditions, but air quality can differ across neighbourhoods and change throughout the day, so local values may vary from those presented here.

OpenAQ station rows