MediumAir QualityCS: 29 · v5

Air Quality near Sofia, Bulgaria (AQI 153)

BulgariaOpenAQ and the agency that runs each station

Right now

The most recent data we hold from OpenAQ and the agency that runs each station arrived 30 minutes ago.

Nothing else has been detected within 20 km in the last 24 hours.

This page covers the record dated 7 November 2026. Browse recent observations in this area:

Distance and hazards
Only these hazards

Tick none to hear about every hazard.

One message per event, not per detection. We send a confirmation first, and every message carries a link to stop them. We store the address and the place, nothing else.

Reported by OpenAQ and the agency that runs each station today.

It is the 4th strongest of the 7 detections recorded within 20 km of this point since 14 March 2026. The last comparable one was on 25 September 2026.

What the source measured

OpenAQ and the agency that runs each station reported: PM2.5 24-hour mean 58.1 µg/m³ at AMS Kopitoto, Bulgaria: Unhealthy, AQI 153 on the US EPA scale. 19 of 24 hours measured, ending 2026-11-07 17:00 UTC. Measured by a government monitoring agency via EEA and OpenAQ; licence ODC-BY.

The air quality index read 153 (Unhealthy) at the AMS Kopitoto station.

Nearby, since 14 March 2026

How we know

One source: OpenAQ and the agency that runs each station. Not yet confirmed by a second, independent source.

Our own score for this event is 29 out of 100.

This is our versioned heuristic index, not source severity or a calibrated probability. Urban PEI does not count unique people.

Computed under scoring rules v5. Rows carrying other versions were judged by different rules and are not directly comparable.

Series begins 8 March 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.

Event data

TypeAir Quality
SeverityMedium
Calamity Score (ours)29 / 100
Legacy data-support index0.50/1
Coordinates42.6372, 23.2439
Nearest citySofia (9 km)
Urban exposure index (PEI)0 within 5 km
Impact tierminor
Timestamp2026-11-07T17:00:00.000Z
Sourcehttps://explore.openaq.org/locations/8846
LicenceODC-BY · EEA, via OpenAQ

Physical priority index · v5. Heuristic priority, not calibrated probability, predictive accuracy or damage. The legacy data-support index combines assigned source support and field availability. Urban PEI is distance-weighted and does not count unique people; zero does not establish that nobody is present. Model cards.

Source and revision timeline

Source: openaq. Occurrence: 2026-11-07T17:00:00.000Z.

First archived: 2026-11-07T19:28:54.304Z. Material modification: not recorded.

Retained revisions are prospective; earlier versions may be unavailable. No revision entry does not prove that a record never changed.

Score breakdown

65
intensity
0
Urban PEI term
0
Scenario weight
33
Recorded reference / batch anomaly

Technical details

Aqi153
AqiCategoryUnhealthy
AqiCategoryVersionUS-EPA-PM25-2024-05-06
AqiProvenanceCalamity: US EPA PM2.5 24-hour breakpoints applied to the station's 24-hour mean; not an official AQI
Pm2558.1
MeasurementUnitug/m3
AveragingPeriod24 hours
PeriodFrom2026-11-06T17:00:00.000Z
PeriodTo2026-11-07T17:00:00.000Z
HoursMeasured19
LatestHourly80
StationNameAMS Kopitoto
StationId8846
SensorId6283928
LocalityСофия (столица)
CountryBulgaria
CountryCodeBG
ProviderEEA
LicenceODC-BY
LicenceUrls["https://opendatacommons.org/licenses/by/odc_by_1.0_public_text.txt"]

Safety information

What to do when the air is unhealthy

Three things first, then what each level of the index means. From the US EPA’s AirNow.

For this reportAir Quality · Sofia

  1. Less effort outdoors

    Shorten or move indoors hard activity; the worse the index, the more people it concerns.

    AirNow
  2. Keep indoor air clean

    Windows closed when the air outside is worse, an air purifier if you have one.

    AirNow
  3. A real mask outside

    A well-fitting N95/FFP2 filters fine particles; cloth and surgical masks do little.

    AirNow

Before, during, after. Here it is still “during”.

Before · When bad air is forecast

  • Follow the index

    Your local air quality index and forecast.

  • Medicines at hand

    If you have asthma or a heart or lung condition, keep your medicines with you.

AirNow (US EPA)

During · While the air is bad

  • Children, older people, the sick

    They are the first to reduce effort outdoors.

  • Watch for symptoms

    Coughing, breathlessness, chest pain: stop and get help if needed.

AirNow (US EPA)

After · When it improves

  • Air the house

    When the outside air is better than inside.

AirNow (US EPA)

If a life is in danger

112

Emergency number: Bulgaria

Call 112

Questions people ask

What do the index levels mean?

0-50 good; 51-100 moderate; 101-150 unhealthy for sensitive groups; 151-200 unhealthy, for everyone; 201-300 very unhealthy; over 300 hazardous. Source: AirNow (US EPA).

Who are the sensitive groups?

People with heart or lung disease, older adults, children and teenagers, pregnant women and people who work or exercise outdoors. Source: AirNow (US EPA).

Follow this area

Review the area, threshold and delivery channel in your account.