Air Quality Lab — Siem Reap, Cambodia
Air Quality Profile
Siem Reap reports an annual PM2.5 of 22.9 µg/m³. That's meaningfully above the WHO 2021 guideline of 5 µg/m³ yet within the EU annual limit of 25 µg/m³.
Siem Reap
Cambodia
CambodiaAnnual Average
ModerateWHO annual classification
22.9µg/m³
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
PM2.5
2626 µg/m³ — Poor
3636 µg/m³ — Unhealthy
3838 µg/m³ — Unhealthy
2929 µg/m³ — Poor
1818 µg/m³ — Moderate
1616 µg/m³ — Moderate
1616 µg/m³ — Moderate
1515 µg/m³ — Fair
1616 µg/m³ — Moderate
2121 µg/m³ — Moderate
1919 µg/m³ — Moderate
2525 µg/m³ — Moderate
Jan
Feb
Mar
Apr
May
Jun
2626 µg/m³ — Poor
3636 µg/m³ — Unhealthy
3838 µg/m³ — Unhealthy
2929 µg/m³ — Poor
1818 µg/m³ — Moderate
1616 µg/m³ — Moderate
Jul
Aug
Sep
Oct
Nov
Dec
1616 µg/m³ — Moderate
1515 µg/m³ — Fair
1616 µg/m³ — Moderate
2121 µg/m³ — Moderate
1919 µg/m³ — Moderate
2525 µg/m³ — Moderate
Best months: Jun–AugWorst months: Feb–Apr
Fair10–15 µg/m³Moderate15–25 µg/m³Poor25–35 µg/m³Unhealthy35–50 µg/m³
Based on WUSTL PM2.5 dataset (2020–2024) · WHO 2021 thresholds
Confidence: ●●●
How air quality compares
Compared across Cambodia
Siem Reap: 22.9 µg/m³. Typical range in Cambodia: 20.9–23.4 µg/m³. Low anchor: Sihanoukville, 17.4 µg/m³. High anchor: Phnom Penh, 32.2 µg/m³.
27 cities tracked