Air quality in Siero, Asturias, Spain today

Mr. Duck’s Air Quality Score

Moderate air today for Siero, Asturias, Spain

⚠️ 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 Siero today is classified as Moderate. The primary pollutant identified is PM2.5 (fine particles). Measurements show a PM2.5 reference value of 10.0 and a PM10 reference value of 15.0, based on five valid observations collected via OpenAQ.

Overall conditions reflect the moderate category with these particulate values recorded for the day. 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 air‑quality record for Siero draws on a single monitoring site that supplies seven separate pollutant measurements. All seven pollutants tracked by OpenAQ are represented: carbon monoxide (CO), nitrogen oxide (NO), nitrogen dioxide (NO₂), ozone (O₃), particulate matter ≤10 µm (PM10), particulate matter ≤2.5 µm (PM2.5) and sulfur dioxide (SO₂). Because the data come from one station, the spatial coverage is limited to the immediate vicinity of that sensor.

Most of the values are very recent, with the latest updates recorded on 2026‑02‑09 between 03:00 and 15:00 UTC for CO, NO₂, O₃, PM10, PM2.5 and SO₂, and on 2024‑01‑31 00:00 UTC for NO. The “updated within 7 days” flag applies to six of the seven pollutants, indicating that the majority of the dataset reflects current conditions, while the nitrogen oxide reading is older by more than a year. For each pollutant the reported concentration is identical across its minimum, median and maximum statistics, meaning there is no observed variability in the single‑row snapshot: CO registers 570 µg/m³, NO 33 µg/m³, NO₂ 44 µg/m³, O₃ 10 µg/m³, PM10 15 µg/m³, PM2.5 10 µg/m³ and SO₂ 4 µg/m³.

Given the uniformity of the numbers and the limited number of measurement points, the dataset provides a narrow picture of air quality in Siero. While the recent timestamps suggest that most readings are up‑to‑date, the lack of multiple stations or repeated observations means that temporal trends and local variations across the city cannot be captured from this source alone. Users should keep in mind that conditions may differ elsewhere in Siero or change over time beyond what a single, static record can show.

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 for Siero is based on five valid measurements and was refreshed recently, with the latest update recorded at 2026‑02‑09T15:00:00+00:00 (updated within 3 days). These values represent a snapshot of ambient conditions and may not reflect variations that occur across different neighbourhoods or times of day within the city.

OpenAQ station rows