SmogRank / World / Europe / The Netherlands / Friesland
Most polluted cities in Friesland, The Netherlands
1 measured city, last 7 days; 0 above the WHO 24-hour guideline. Worst: Kollum at 8.1 µg/m³, #1,017 in the world.
48 monitors in The Netherlands stopped reporting on 4 Oct, 02:00 local time. Cities that rely on them are missing from the 24-hour board and may drop from the longer ones; that isn't clean air, and they return when the data does.
- 1Kollum 45
The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales
Estimated: cities without a monitor
Friesland cities we can't measure, with model estimates for the last 7 days. Listed by population, not ranked: estimates aren't precise enough to rank. Model estimates from the Copernicus Atmosphere Monitoring Service (CAMS), adjusted to measured cities nearby where there are any. Adjusted, a single day lands within ×1.5 of what a monitor would read about two times in three; unadjusted, it can be off by half or double. Treat them as a guide, not a measurement.
| City | 7-day estimate |
|---|---|
| Leeuwarden | ≈ 9 µg/m³ |
| Drachten | ≈ 8 µg/m³ |
| Heerenveen | ≈ 10 µg/m³ |
| Sneek | ≈ 8 µg/m³ |
| Harlingen | ≈ 8 µg/m³ |
Bad-air episodes in Friesland
- Europe, 18 to 25 March 202618 to 25 March 2026, 8 days430 cities136 µg/m³peak, Łask
- Europe, 1 to 12 March 20261 to 12 March 2026, 12 days532 cities109 µg/m³peak, Radomsko
- Europe, January and February 202612 January to 12 February 2026, 32 days625 cities252 µg/m³peak, Travnik
- Europe, March 202519 to 30 March 2025, 12 days401 cities83 µg/m³peak, Kikinda
- Germany, Poland and 25 more countries, March 20253 to 13 March 2025, 11 days553 cities152 µg/m³peak, Negotin
- Europe, 14 February to 1 March 202514 February to 1 March 2025, 16 days619 cities178 µg/m³peak, Krotoszyn
Times when many cities around here had PM2.5 at twice their usual or more on the same days.
Use this board
SmogRank, most polluted cities in Friesland, The Netherlands, PM2.5, last 7 days to 5 Oct 2026, 03:00 UTC, smogrank.com/nl/region/friesland?w=7d.
You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.
Updated 2026-10-05 03:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index.