Most polluted cities in Costa Rica, May 2026

No city in Costa Rica had measurements on 70% of the days, so May 2026 has no board for Costa Rica.

Low1–3

Moderate4–6

High7–9

Very high10

The UK's Daily Air Quality Index (1 to 10), PM2.5 bands. Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales