Reported by World Air Quality Index 27 days ago.
It is the 4th strongest of the 28 detections recorded within 20 km of this point since 14 March 2026. The last comparable one was on 4 July 2026.
What the source measured
World Air Quality Index reported: AQI 779 (Hazardous) at Nadezhda, Sofia, Bulgaria (Нaдeждa, Столична)
An estimated 116,684 people live within 5 km of this point.
How we know
Confirmed by 4 independent sources, including World Air Quality Index.
Our own score for this event is 35 out of 100, at 74 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
Event Data
| Type | Air quality |
| Severity | critical |
| Calamity Score (ours) | 35 / 100 |
| Our confidence | 74% |
| Coordinates | 42.7325, 23.2986 |
| Nearest City | Sofia (4 km) |
| Population Exposed | 116.7K within 5 km |
| Impact Tier | severe |
| Timestamp | 2026-08-03T06:00:00.000Z |
| Source | https://aqicn.org/city/@8088 |
Score Breakdown
Technical Details
| Aqi | 779 |
| AqiCategory | Hazardous |
| StationName | Nadezhda, Sofia, Bulgaria (Нaдeждa, Столична) |
| StationUid | 8088 |
| Sensor Community Pm25Max | 999.9 |
| Sensor Community Pm25Avg | 999.9 |
| Sensor Community SensorCount | 1 |
| Sensor Community AqiCategory | Hazardous |
| Sensor Community ClusterKey | 42.6_23.3 |
| MergedSources | [{"id":"sensor_community_42.8_23.3","source":"sensor_community","severity":"high","severityValue":74.112,"timestamp":1785737336000,"latitude":42.804,"longitude":23.342},{"id":"sensor_community_42.7_23.3","source":"sensor_community","severity":"critical","severityValue":92.7786,"timestamp":1785737337000,"latitude":42.726,"longitude":23.342},{"id":"sensor_community_42.6_23.3","source":"sensor_community","severity":"critical","severityValue":98.998,"timestamp":1785737281000,"latitude":42.642,"longitude":23.31}] |
Safety Information
When air quality is hazardous: stay indoors with windows closed, and run a filtered air purifier if you have one. Avoid outdoor exercise. Children, older adults and anyone with heart or lung conditions are affected first and worst — an N95 respirator helps outdoors, a cloth mask does not.
Series begins 10 February 2026. Comparisons refer to that period only. Collection gap: 14-26 August 2026.
This data is aggregated algorithmically from scientific sources. Not a replacement for official emergency warnings.
Calamity.live data shows a air quality event with CalamityScore 35/100, near Sofia (Bulgaria), based on data from waqi. Source: Calamity.live, a platform aggregating real-time data from 191 scientific monitoring sources.