Air quality in Herstal, Liège, Belgium today

Mr. Duck’s Air Quality Score

Good air today for Herstal, Liège, Belgium

⚠️ 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 Herstal today is classified as Good. The main pollutant identified is PM2.5 (fine particles). Measurements show a PM2.5 reference value of 0.0 and a PM10 reference value of 0.771, based on four valid observations collected via OpenAQ.

These figures indicate that the current concentrations are within the limits associated with the Good category. 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 Herstal air‑quality record draws on a single monitoring site that supplies five data rows covering the five pollutants tracked in this city: nitrogen dioxide, ozone, particulate matter ≤ 10 µm, particulate matter ≤ 2.5 µm and sulphur dioxide. Four of those rows have been refreshed within the last three days, so the most recent measurements for NO₂ (30.5 µg/m³), O₃ (39.5 µg/m³), PM10 (0.771 µg/m³) and PM2.5 (0.0 µg/m³) all carry a timestamp of 2026‑02‑10 18:00 UTC. The SO₂ reading is much older, dated 2016‑12‑21 13:00 UTC, and therefore reflects historic conditions rather than the current state.

All five pollutants show a single reported value – the minimum, median and maximum are identical for each. NO₂ sits at 30.5 µg/m³, O₃ at 39.5 µg/m³, PM10 at 0.771 µg/m³, PM2.5 registers as zero, and SO₂ records 1.0 µg/m³. Because the dataset contains only one station, there is no spatial spread of measurements across Herstal; variations that might exist in different neighbourhoods are not captured here. The recent freshness of four pollutants gives a snapshot of today’s air composition, while the outdated sulphur‑dioxide figure highlights an uneven temporal coverage among the monitored substances.

Overall, the data set offers a concise but limited view: it includes all five standard pollutants, provides up‑to‑date values for most of them from a single location, and contains one legacy measurement that should be interpreted with caution when considering current conditions in Herstal.

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 Herstal reflects four valid measurements and was refreshed recently, with the latest update recorded on 2026‑02‑10 at 18:00 UTC; it is considered “Updated within 3 days.” This snapshot provides a brief view of current conditions, but air quality can differ across neighbourhoods and change throughout the day, so values may not represent every location or moment in the city.

OpenAQ station rows