Air quality in San Sebastián, Autonomous Community of the Basque Country, Spain today

Mr. Duck’s Air Quality Score

Moderate air today for San Sebastián, Autonomous Community of the Basque Country, 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 San Sebastián today is classified as Moderate. The primary pollutant identified is PM2.5, based on 20 valid measurements reported through OpenAQ. Data is shown via OpenAQ and reflects the latest sampling for the area.

Current observations show PM2.5 concentrations near the reference value of 11.0 µg/m³, while PM10 levels are around the reference value of 34.0 µg/m³. The reference values applied are 11.0 µg/m³ for PM2.5 and 34.0 µg/m³ for PM10. These figures are consistent with the Moderate category assigned to the city. The reported values provide a snapshot of particulate matter levels at this time. 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 OpenAQ feed for San Sebastián includes seven measured pollutants – carbon monoxide (CO), nitrogen monoxide (NO), nitrogen dioxide (NO₂), ozone (O₃), particulate matter 10 µm (PM10), particulate matter 2.5 µm (PM2.5) and sulphur dioxide (SO₂). Across the city the dataset contains 32 individual rows drawn from seven monitoring stations, giving a modest spatial spread of observations. All pollutants except NO have recent updates, with the latest timestamps recorded on 2026‑02‑09 15:00 UTC. The NO data are older, last refreshed on 2024‑01‑16 23:00 UTC, which means that the nitrogen monoxide record is less current than the rest of the suite.

The recorded values show a fairly wide spread for most species. CO ranges from 230 µg/m³ to 250 µg/m³ with a median of 240 µg/m³, and the most recent reading is 250 µg/m³ at the ATEGORRIETA site. NO₂ varies between 7 µg/m³ and 31 µg/m³, median 16 µg/m³, with a current value of 24 µg/m³ at the same station. PM10 values sit between 3 µg/m³ and 34 µg/m³ (median 7 µg/m³) and the latest measurement is 4 µg/m³ at PUYO; PM2.5 spans 1 µg/m³ to 11 µg/m³ (median 5 µg/m³) with a current 1 µg/m³ at PUYO. Ozone is recorded from 57 µg/m³ up to 77 µg/m³ (median 60.5 µg/m³), the newest figure being 62 µg/m³ at PUYO. SO₂ ranges from 1 µg/m³ to 3 µg/m³ (median 2 µg/m³) with a latest reading of 3 µg/m³ at PUYO. NO, based on only two rows, shows values from 1 µg/m³ to 2 µg/m³ (median 1.5 µg/m³) and the most recent entry is 1 µg/m³ at ES1697A.

These numbers illustrate that most pollutants are captured frequently and updated within the last month, while nitrogen monoxide has limited and older coverage. The median concentrations are generally well below the observed maxima, indicating occasional spikes that are not reflected in the typical daily levels. Because the data come from a handful of stations, conditions can differ across neighborhoods and times, especially for the less‑frequently recorded NO.

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 dataset for San Sebastián includes 20 valid measurements and is updated within 30 days. The most recent data were recorded on 2026-02-09 at 15:00 UTC. This snapshot reflects conditions at the time of sampling, but air quality can vary by location and time within the city. Users should consider these factors when interpreting the information presented.

OpenAQ station rows