Armenia is introducing a new system for assessing ambient air quality. Separate standards have been set for fine particles PM2.5 and PM10, while the main pollutants will have defined averaging periods, permitted exceedances and public information thresholds.
Government Decision No. 1142-N was adopted on 14 August 2025. It was originally due to take effect in 2030, but amendments adopted on 23 April 2026 moved the effective date to 1 November 2027. A second stage is scheduled for 1 January 2035.
This article explains the main provisions and compares the new values with the standards currently in force. It is not a critical or legal analysis of the decision and does not assess whether the measures are sufficient.
What changes in the approach
Armenia currently applies Decision No. 160-N of 2 February 2006. It contains maximum one-time and daily-average permissible concentrations for a long list of substances. PM2.5 and PM10 are not regulated separately; instead, there is a general value for suspended particles without differentiation by size or composition.
The new decision introduces several assessment periods:
- a one-hour average;
- a 24-hour average;
- the maximum daily eight-hour average;
- a calendar-year average;
- a separate six-month indicator for ozone.
Current and new standards
The table covers the main pollutants included in the WHO guidelines. Current rules are shown as daily-average and maximum one-time concentrations. The new rules use the averaging periods defined by Decision No. 1142-N. Values are in µg/m³, except for CO, which is shown in mg/m³.
| Pollutant | Current standard | From 1 November 2027 | From 1 January 2035 | Information threshold from 2027 |
|---|---|---|---|---|
| PM2.5 | No separate standards. Undifferentiated suspended particles: 150 µg/m³ daily average and 500 µg/m³ maximum one-time concentration | 25 µg/m³ over 24 hours, up to 18 exceedances per year; 10 µg/m³ annual average |
15 µg/m³ over 24 hours, no more than 3 exceedance days; 5 µg/m³ annual average |
50 µg/m³ over 24 hours — US AQI 137 |
| PM10 | 45 µg/m³ over 24 hours, up to 18 exceedances per year; 20 µg/m³ annual average |
45 µg/m³ over 24 hours, no more than 3 exceedance days; 15 µg/m³ annual average |
90 µg/m³ over 24 hours — US AQI 68 | |
| NO₂ | 40 µg/m³ daily average; 85 µg/m³ maximum one-time concentration |
200 µg/m³ over 1 hour, up to 3 exceedances per year; 50 µg/m³ over 24 hours, up to 18 exceedances; 20 µg/m³ annual average |
25 µg/m³ over 24 hours, no more than 3 exceedance days; 10 µg/m³ annual average |
150 µg/m³ over 1 hour — US AQI 79 |
| SO₂ | 50 µg/m³ daily average; 500 µg/m³ maximum one-time concentration |
350 µg/m³ over 1 hour, up to 3 exceedances per year; 50 µg/m³ over 24 hours, up to 18 exceedances; 20 µg/m³ annual average |
40 µg/m³ over 24 hours, no more than 3 exceedance days | 275 µg/m³ over 1 hour — US AQI 114 |
| CO | 3 mg/m³ daily average; 5 mg/m³ maximum one-time concentration |
10 mg/m³ maximum eight-hour average; 4 mg/m³ over 24 hours, up to 18 exceedances |
4 mg/m³ over 24 hours, no more than 3 exceedance days | Not established |
| O₃ | 30 µg/m³ daily average; 160 µg/m³ maximum one-time concentration |
100 µg/m³ maximum eight-hour average, no more than 3 exceedance days | 100 µg/m³ maximum eight-hour average, no more than 3 exceedance days; 60 µg/m³ during peak season |
180 µg/m³ over 1 hour; conditionally US AQI 166 if this concentration persisted for 8 hours |
The AQI figures in the last column are calculated using the US AQI scale used by AirQuality.am. A detailed AQI calculation table is available on a separate page. These figures are not part of the decision and do not become official Armenian thresholds.
The decision also introduces higher alert thresholds: 350 µg/m³ for SO₂, 200 for NO₂ and 240 for ozone. The PM2.5 and PM10 concentrations remain 50 and 90 µg/m³ respectively, but an alert is based on the daily average being reached on three consecutive days.
A two-stage transition
The first set of new standards will apply from 1 November 2027 through the end of 2034. During this period, the daily PM2.5, PM10, NO₂, SO₂ and CO values may be exceeded up to 18 times per calendar year.
From 1 January 2035, several values become stricter and the permitted number of exceedance days falls to three. The annual PM2.5 value, for example, falls from 10 to 5 µg/m³, while NO₂ falls from 20 to 10 µg/m³.
Connection with WHO guidelines
The second stage reproduces the core values in the 2021 WHO Global Air Quality Guidelines for six classical pollutants:
- PM2.5 — 5 µg/m³ annual and 15 µg/m³ daily;
- PM10 — 15 µg/m³ annual and 45 µg/m³ daily;
- NO₂ — 10 µg/m³ annual and 25 µg/m³ daily;
- SO₂ — 40 µg/m³ daily;
- CO — 4 mg/m³ daily;
- ozone — a maximum eight-hour average of 100 µg/m³ and a peak-season value of 60 µg/m³.
Some of these values will already apply in the first stage. The daily PM10 value and eight-hour ozone value, for example, will numerically match the WHO guidelines from 2027, although more exceedance days will initially be allowed. Most other transitional values correspond to WHO interim targets intended to support gradual pollution reduction.
WHO guidelines are health-based recommendations and are not laws by themselves. The decision brings their numerical values into Armenia’s regulatory system and establishes the transition dates.
How air quality will be assessed
The decision provides for three assessment methods:
- fixed measurements at the same location with continuous sampling for at least one calendar year;
- indicative measurements performed periodically or through sample-based observations;
- modelling based on emissions, meteorological conditions and terrain.
International reference methods are specified for official monitoring. PM2.5 and PM10, for example, are covered by the EN 12341 gravimetric method and EN 16450 automated systems; NO₂ by chemiluminescence under EN 14211; and ozone by ultraviolet photometry under EN 14625.
The affordable optical sensors displayed by AirQuality.am do not become reference instruments. They serve a different purpose: showing changes in pollution in real time and supplementing the sparse official network. An official assessment of compliance will require measurements of the specified quality over the period defined in the decision.
The new system is due to begin on 1 November 2027, provided the date is not postponed again and preparations proceed as planned. Until then, the existing permissible concentrations, which do not yet distinguish PM2.5 from PM10, remain in force. We will follow further changes and report on how the new standards are implemented in practice.