Air quality
Air quality in Cluj-Napoca today
Updated
Moderate (US AQI 61) Acceptable for most people. Unusually sensitive people should consider shortening long or heavy exertion outdoors. Model estimate for Mon, Oct 26, 4:00 am (02:00 UTC).
Live AQI, PM2.5, PM10 and ozone for Cluj-Napoca, Cluj County, Romania, with a 48-hour forecast and the best time to be outside.
- US AQI now
- 61 Moderate
- PM2.5
- 11 µg/m³ 0.8× WHO 24-h guideline
- PM10
- 14 µg/m³
- Ozone
- 37 µg/m³
- Dominant pollutant
- PM2.5 sub-index 61
- Best hour today
- 9:00 pm AQI 57
- European AQI
- 33
Air quality in Cluj-Napoca right now
Right now the modelled US Air Quality Index for Cluj-Napoca, Cluj County, Romania is 61, which falls in the "Moderate" band (up to 100). Acceptable for most people. Unusually sensitive people should consider shortening long or heavy exertion outdoors.
The index is driven mainly by PM2.5, whose own sub-index is 61. Fine and coarse particles come from traffic, heating, industry, dust and smoke; they build up on calm nights and clear when wind or rain arrives.
PM2.5 is 11 µg/m³, within the WHO 24-hour guideline of 15 µg/m³; PM10 is 14 µg/m³ against a guideline of 45; ozone is 37 µg/m³ (below the WHO 8-hour level of 100); nitrogen dioxide is 6.3 µg/m³ (below the 24-hour guideline of 25).
Also this hour: carbon monoxide 195 µg/m³.
NASA FIRMS shows 6 fire hotspots within 300 km in the last day (nearest about 158 km), but particle levels are not elevated enough to point to smoke right now.
Cluj-Napoca AQI forecast: next 48 hours
Over the next 24 hours the AQI is forecast to range from 50 around Tue 4:00 am to 62 around Mon 7:00 am, from "Good" at best to "Moderate" at worst.
The following day is expected to be cleaner, averaging about 45 against 59 for the next 24 hours.
| Local time (Europe/Bucharest) | US AQI | Category | PM2.5 µg/m³ | PM10 µg/m³ | Ozone µg/m³ |
|---|---|---|---|---|---|
| Mon 4:00 am | 61 | Moderate | 11.4 | 14 | 37 |
| Mon 7:00 am | 62 | Moderate | 14.5 | 19 | 29 |
| Mon 10:00 am | 62 | Moderate | 15.5 | 18 | 27 |
| Mon 1:00 pm | 62 | Moderate | 10.3 | 13 | 52 |
| Mon 4:00 pm | 61 | Moderate | 4.3 | 5 | 51 |
| Mon 7:00 pm | 59 | Moderate | 7.5 | 8 | 53 |
| Mon 10:00 pm | 55 | Moderate | 6.6 | 7 | 49 |
| Tue 1:00 am | 52 | Moderate | 4.6 | 6 | 48 |
| Tue 4:00 am | 50 | Good | 5.8 | 7 | 41 |
| Tue 7:00 am | 47 | Good | 7.9 | 10 | 39 |
| Tue 10:00 am | 43 | Good | 8.7 | 11 | 43 |
| Tue 1:00 pm | 38 | Good | 8.3 | 10 | 46 |
| Tue 4:00 pm | 38 | Good | 7.7 | 10 | 50 |
| Tue 7:00 pm | 42 | Good | 16.8 | 19 | 37 |
| Tue 10:00 pm | 48 | Good | 15.5 | 17 | 38 |
| Wed 1:00 am | 51 | Moderate | 11.7 | 14 | 36 |
| Wed 4:00 am | 53 | Moderate | 9.3 | 12 | 36 |
Every third hour of the CAMS forecast via Open-Meteo. US AQI uses rolling averages (24 h for particles, 8 h for ozone), so it moves more slowly than the hourly concentrations.
Best time to be outside in Cluj-Napoca today
Between 6 am and 9 pm local time, the cleanest air today is forecast around 9:00 pm (AQI 57, Moderate) and the worst around 7:00 am (AQI 62). The difference across the day is small, so timing matters little.
Cluj-Napoca vs the rest of Romania
Across 6 Romania cities we track, the average US AQI right now is 51 (Moderate). Cluj-Napoca at 61 is 10 points worse than average.
It ranks 6 of 6 from cleanest to most polluted; the cleanest is Constanţa (35) and the most polluted Cluj-Napoca (61).
For context, the median across 3,556 cities worldwide is 58.
Air quality in cities near Cluj-Napoca
| City | Distance | US AQI | Category | PM2.5 µg/m³ |
|---|---|---|---|---|
| Roman | 254 km | 55 | Moderate | 10.5 |
| Iaşi | 307 km | 49 | Good | 8.5 |
| Bucharest | 325 km | 58 | Moderate | 12.5 |
| Belgrade | 327 km | 78 | Moderate | 35.4 |
| Zemun | 327 km | 78 | Moderate | 35.4 |
| Novi Beograd | 329 km | 78 | Moderate | 35.4 |
| Alexandria, Teleorman County | 338 km | 50 | Good | 8.6 |
| Lviv | 343 km | 51 | Moderate | 7.8 |
Model vs measured
The nearest measured PM2.5 reading is 8.9 µg/m³ from Sensor.Community (median of 23 sensors), centred about 3 km from the city centre. That is close to the model estimate of 11 µg/m³. Low-cost sensors can read high in humid air; reference monitors are more accurate but sparser.
Advice for sensitive groups
At 61, most people are fine outdoors. If you are unusually sensitive to PM2.5, keep long or intense workouts to the cleaner hours shown above.
What the US AQI numbers mean
| US AQI | Category | What it means |
|---|---|---|
| 0-50 | Good | Air quality is satisfactory and poses little or no risk; a good time for outdoor activity. |
| 51-100 | Moderate | Acceptable for most people. Unusually sensitive people should consider shortening long or heavy exertion outdoors. |
| 101-150 | Unhealthy for Sensitive Groups | People with heart or lung disease, older adults, children and teens should cut back on prolonged or heavy exertion outdoors. |
| 151-200 | Unhealthy | Everyone should reduce prolonged or heavy exertion outdoors; sensitive groups should avoid it and keep windows closed. |
| 201-300 | Very Unhealthy | Health alert: everyone should avoid prolonged or heavy exertion outdoors, and sensitive groups should stay indoors. |
| 301-500 | Hazardous | Emergency conditions: everyone should avoid all outdoor physical activity and stay indoors with filtered air if possible. The scale tops out at 500; heavier dust or smoke is shown as 500. |
Values on this page are modelled by CAMS (Copernicus) and served by Open-Meteo; they are estimates for the area around the city centre, not readings from an official monitor.
Nearby cities
More for Cluj-Napoca
Air quality elsewhere
Data: Open-Meteo Air Quality API, Copernicus Atmosphere Monitoring Service (CAMS), Sensor.Community, NASA FIRMS.