Latest Annual AQI
The Annual Air Quality Index (AAQI) is the ratio of the past 12-month rolling average concentration to the annual air quality guidelines (AQG) of the World Health Organization (WHO).
Air Pollutant Concentrations (μg/m3)
Period: April 2021 - March 2022
General Stations
| Station | NO2 | PM10 | PM2.5 |
|---|---|---|---|
| Central/Western | 32 | 23 | 15 |
| Southern | 29 | 24 | 12 |
| Eastern | 34 | 26 | 14 |
| Kwun Tong | 47 | 27 | 16 |
| Sham Shui Po | 45 | 25 | 13 |
| Kwai Chung | 48 | 24 | 16 |
| Tsuen Wan | 42 | 23 | 15 |
| Tseung Kwan O | 24 | 22 | 13 |
| Yuen Long | 39 | 27 | 17 |
| Tuen Mun | 41 | 32 | 18 |
| Tung Chung | 26 | 24 | 16 |
| Tai Po | 29 | 23 | 14 |
| Sha Tin | 29 | 22 | 13 |
| North | 34 | 23 | 14 |
| Tap Mun | 9 | 21 | 12 |
Roadside Stations
| Station | NO2 | PM10 | PM2.5 |
|---|---|---|---|
| Causeway Bay | 68 | 36 | 22 |
| Central | 65 | 27 | 17 |
| Mong Kok | 66 | 27 | 17 |
Annual AQI Values
Period: April 2021 - March 2022
General Station
| Station | NO2 | PM10 | PM2.5 |
|---|---|---|---|
| Central/Western | 0.80 | 1.15 | 1.50 |
| Southern | 0.73 | 1.20 | 1.20 |
| Eastern | 0.85 | 1.30 | 1.40 |
| Kwun Tong | 1.18 | 1.35 | 1.60 |
| Sham Shui Po | 1.13 | 1.25 | 1.30 |
| Kwai Chung | 1.20 | 1.20 | 1.60 |
| Tsuen Wan | 1.05 | 1.15 | 1.50 |
| Tseung Kwan O | 0.60 | 1.10 | 1.30 |
| Yuen Long | 0.98 | 1.35 | 1.70 |
| Tuen Mun | 1.03 | 1.60 | 1.80 |
| Tung Chung | 0.65 | 1.20 | 1.60 |
| Tai Po | 0.73 | 1.15 | 1.40 |
| Sha Tin | 0.73 | 1.10 | 1.30 |
| North | 0.85 | 1.15 | 1.40 |
| Tap Mun | 0.23 | 1.05 | 1.20 |
Roadside
| Station | NO2 | PM10 | PM2.5 |
|---|---|---|---|
| Causeway Bay | 1.70 | 1.80 | 2.20 |
| Central | 1.63 | 1.35 | 1.70 |
| Mong Kok | 1.65 | 1.35 | 1.70 |
Remarks:
(1) The AAQI is updated monthly. The AAQI is calculated based on validated monitoring data.
(2) An AAQI greater than one indicates that the health risk resulted from long-term exposure is higher than that of the WHO's annual AQG, whereas an index below one means a lower risk.
(3) WHO’s annual AQG (2006):
Reference: http://www.who.int/phe/health_topics/outdoorair/outdoorair_aqg/en/index.html
Annual WHO AQG
(μg/m3)
NO2
40
PM10
20
PM2.5
10
For further information about the annual AQI, please visit the FAQ.
(4) NO2 - nitrogen dioxide, PM10 - respirable suspended particulates, PM2.5 - fine suspended particulates