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).

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Air Pollutant Concentrations (μg/m3)
Period: July 2020 - June 2021

General stations
Central/Western
latestAPC_80.png
Southern
latestAPC_84.png
Eastern
latestAPC_73.png
Kwun Tong
latestAPC_74.png
Sham Shui Po
latestAPC_66.png
Kwai Chung
latestAPC_72.png
Tsuen Wan
latestAPC_77.png
Tseung Kwan O
latestAPC_83.png
Yuen Long
latestAPC_70.png
Tuen Mun
latestAPC_82.png
Tung Chung
latestAPC_78.png
Tai Po
latestAPC_69.png
Sha Tin
latestAPC_75.png
North
latestAPC_85.png
Tap Mun
latestAPC_76.png
Roadside stations
Causeway Bay
latestAPC_71.png
Central
latestAPC_79.png
Mong Kok
latestAPC_81.png

Air Pollutant Concentrations (μg/m3)
Period: July 2020 - June 2021

General Stations

StationNO2PM10PM2.5
Central/Western332716
Southern292714
Eastern353015
Kwun Tong463517
Sham Shui Po463014
Kwai Chung512615
Tsuen Wan402616
Tseung Kwan O242413
Yuen Long343216
Tuen Mun423820
Tung Chung262716
Tai Po322716
Sha Tin302715
North342615
Tap Mun92615
Pollutant concentrations in micrograms per cubic metre (μg/m3)

Roadside Stations

StationNO2 PM10PM2.5
Causeway Bay714024
Central693118
Mong Kok703119
Pollutant concentrations in micrograms per cubic metre (μg/m3)

Annual AQI Values
Period: July 2020 - June 2021

General stations
Central/Western
latestAAQI_80.png
Southern
latestAAQI_84.png
Eastern
latestAAQI_73.png
Kwun Tong
latestAAQI_74.png
Sham Shui Po
latestAAQI_66.png
Kwai Chung
latestAAQI_72.png
Tsuen Wan
latestAAQI_77.png
Tseung Kwan O
latestAAQI_83.png
Yuen Long
latestAAQI_70.png
Tuen Mun
latestAAQI_82.png
Tung Chung
latestAAQI_78.png
Tai Po
latestAAQI_69.png
Sha Tin
latestAAQI_75.png
North
latestAAQI_85.png
Tap Mun
latestAAQI_76.png
Roadside stations
Causeway Bay
latestAAQI_71.png
Central
latestAAQI_79.png
Mong Kok
latestAAQI_81.png

Annual AQI Values
Period: July 2020 - June 2021

General Station

StationNO2PM10PM2.5
Central/Western0.831.351.60
Southern0.731.351.40
Eastern0.881.501.50
Kwun Tong1.151.751.70
Sham Shui Po1.151.501.40
Kwai Chung1.281.301.50
Tsuen Wan1.001.301.60
Tseung Kwan O0.601.201.30
Yuen Long0.851.601.60
Tuen Mun1.051.902.00
Tung Chung0.651.351.60
Tai Po0.801.351.60
Sha Tin0.751.351.50
North0.851.301.50
Tap Mun0.231.301.50
AAQI = 12-month rolling concentrations/Annual WHO AQG concentration

Roadside

StationNO2PM10PM2.5
Causeway Bay1.782.002.40
Central1.731.551.80
Mong Kok1.751.551.90
AAQI = 12-month rolling concentrations/Annual WHO AQG concentration

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):


Annual WHO AQG
(μg/m3)
NO2 40
PM10 20
PM2.5 10

Reference: http://www.who.int/phe/health_topics/outdoorair/outdoorair_aqg/en/index.html

For further information about the annual AQI, please visit the FAQ.

(4) NO2 - nitrogen dioxide, PM10 - respirable suspended particulates, PM2.5 - fine suspended particulates

Last revision date: 04:07 26-10-2021