How we measure
For anyone who wants to know more: where the data comes from, how the level is made and which limit values apply.
Where the data comes from
Hourly values from the official stations in BiH and the region. We get them through the European Environment Agency and show them unchanged.
Hourly values from the state monitoring networks via the index data service of the European Environment Agency. Where no measurement was available for an hour, the service gap-fills from the European air quality forecast; such values are marked here.
Agency for Environmental Protection · Državna mreža za trajno praćenje kvalitete zraka · Environmental Protection Agency of Montenegro · Federal Hydrometeorological Institute · Kosova Environmental Protection Agency ( KEPA) · Ministry of Environment and Physical Planning · Mjerna mreža Cemex Hrvatska d.o.o. · Republic Hydrometeorological Institute of Republic of Srpska · Slovenian Environment Agency
How the level is made
Each pollutant has six levels. A place's level is the level of its worst measured pollutant in the last hour. A reading older than 4 hours is never shown as “now”.
European Air Quality Index of the European Environment Agency, the version following the 2021 revision aligned with the WHO air quality guidelines. Class boundaries, colours and the health assessment are adopted unchanged; the overall class is the worst individual pollutant.
- Good0
- Fair5
- Moderate15
- Poor50
- Very poor90
- Extremely poor140
The colour says how polluted the air is, from Good to Extremely poor. The numbers below say from which reading each level applies.
- Good0
- Fair15
- Moderate45
- Poor120
- Very poor195
- Extremely poor270
The colour says how polluted the air is, from Good to Extremely poor. The numbers below say from which reading each level applies.
- Good0
- Fair10
- Moderate25
- Poor60
- Very poor100
- Extremely poor150
The colour says how polluted the air is, from Good to Extremely poor. The numbers below say from which reading each level applies.
- Good0
- Fair60
- Moderate100
- Poor120
- Very poor160
- Extremely poor180
The colour says how polluted the air is, from Good to Extremely poor. The numbers below say from which reading each level applies.
- Good0
- Fair20
- Moderate40
- Poor125
- Very poor190
- Extremely poor275
The colour says how polluted the air is, from Good to Extremely poor. The numbers below say from which reading each level applies.
When there is no measurement
If a station sends no value, we write “no measurement”. Model estimates do not count as measurements and appear only in the details, labelled. A municipality without a station never takes on its neighbour's colour.
Daily means are only formed with at least 75 % coverage of the day; that is the minimum requirement of Directive 2008/50/EC. The day is the calendar day in local time, not UTC.
Limit values and thresholds
Which value triggers what, and on what basis.
Limit values
The limit and target values of Air Quality Directive 2008/50/EC. The Federation of BiH adopted them through its Pravilnik (Official Gazette FBiH 1/12, 50/19, 3/21), with stricter values for the annual average of sulphur dioxide (50 µg/m³) and the daily average of nitrogen dioxide (85 µg/m³).
| Measurand | Basis | Valueµg/m³ | Permitted exceedances |
|---|---|---|---|
| Particulate matter PM10 | Daily mean | 50 | 35 |
| Particulate matter PM10 | Annual mean | 40 | not applicable |
| Particulate matter PM2.5 | Annual mean | 25 | not applicable |
| Nitrogen dioxide NO₂ | Hourly mean | 200 | 18 |
| Nitrogen dioxide NO₂ | Annual mean | 40 | not applicable |
| Sulphur dioxide SO₂ | Hourly mean | 350 | 24 |
| Sulphur dioxide SO₂ | Daily mean | 125 | 3 |
| Ozone O₃ | highest 8-hour value | 120 | 25 |
| Carbon monoxide CO | highest 8-hour value | 10,000 | not applicable |
Source: Directive 2008/50/EC, Annexes XI and XIV, checked against the text of the EU Official Journal on 7 October 2026. Carbon monoxide is given in mg/m³ in the Official Journal (10 mg/m³) and in µg/m³ here.
Warning thresholds
Three levels, not six: an alert pathway that triggers on every change of class gets muted after the second week.
| Level | Measurand | Threshold | Origin |
|---|---|---|---|
| Information | PM10 | 50Daily mean | samoEKO operational threshold |
| Warning | PM10 | 100Daily mean | samoEKO operational threshold |
| Alert | PM10 | 150Daily mean · 2 consecutive periods | samoEKO operational threshold |
| Information | PM2.5 | 25Daily mean | samoEKO operational threshold |
| Warning | PM2.5 | 50Daily mean | samoEKO operational threshold |
| Alert | PM2.5 | 75Daily mean · 2 consecutive periods | samoEKO operational threshold |
| Alert | SO₂ | 500Hourly mean · 3 consecutive periods | Legislation |
| Alert | NO₂ | 400Hourly mean · 3 consecutive periods | Legislation |
| Warning | O₃ | 180Hourly mean | Legislation |
| Alert | O₃ | 240Hourly mean | Legislation |
Alert and information thresholds under Annex XII of Directive 2008/50/EC, checked against the text of the EU Official Journal on 7 October 2026. The FBiH Pravilnik sets the same thresholds for sulphur dioxide and nitrogen dioxide (Annex XIV).
EU law of 2008 has no alert threshold for particulate matter. The Federation of BiH has had one since 2021: for PM10 a warning threshold of 150 and an alert threshold of 300 µg/m³, for PM2.5 140 and 280 µg/m³, as daily averages (Pravilnik, Official Gazette FBiH 3/21). The levels samoEKO uses for particulate notifications remain operational thresholds, derived from the daily limit and the index scale. Sarajevo Canton keeps its own intervention plan with the stages pripravnost, upozorenje and uzbuna; its threshold values are not yet available to us in documented form, so they are not claimed here.
Directive 2008/50/EC and the recast (EU) 2024/2881, both checked against the text of the EU Official Journal on 7 October 2026. From 2030 the recast lowers several values, for example the annual PM10 limit from 40 to 20 µg/m³. On the station pages it appears only as a comparison; the yardstick is the limits of the Federation of BiH or Republika Srpska.
Our own network
Planned are sensor boxes on lamp posts with a ten-minute measurement cycle. No box stands in the field yet, so for now this portal shows official monitoring stations only. Even in operation the measurement remains indicative: it supplements the official monitoring stations with local resolution, it does not replace them.