Welcome to Environmental Protection Department Air Quality Health Index Website


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 2017 - March 2018

General Stations

StationNO2PM10PM2.5
Central/Western403522
Eastern413319
Kwun Tong443922
Sham Shui Po523221
Kwai Chung583422
Tsuen Wan523322
Tseung Kwan O293017
Yuen Long413923
Tuen Mun484327
Tung Chung363320
Tai Po393221
Sha Tin363121
Tap Mun93319
Pollutant concentrations in micrograms per cubic metre (μg/m3)

Roadside Stations

StationNO2 PM10PM2.5
Causeway Bay984631
Central803321
Mong Kok803826
Pollutant concentrations in micrograms per cubic metre (μg/m3)

Annual AQI Values
Period: April 2017 - March 2018

General Station

StationNO2PM10PM2.5
Central/Western1.001.752.20
Eastern1.031.651.90
Kwun Tong1.101.952.20
Sham Shui Po1.301.602.10
Kwai Chung1.451.702.20
Tsuen Wan1.301.652.20
Tseung Kwan O0.731.501.70
Yuen Long1.031.952.30
Tuen Mun1.202.152.70
Tung Chung0.901.652.00
Tai Po0.981.602.10
Sha Tin0.901.552.10
Tap Mun0.231.651.90
AAQI = 12-month rolling concentrations/Annual WHO AQG concentration

Roadside

StationNO2PM10PM2.5
Causeway Bay2.452.303.10
Central2.001.652.10
Mong Kok2.001.902.60
AAQI = 12-month rolling concentrations/Annual WHO AQG concentration

Remarks:

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

(2) The AAQI is updated monthly. The AAQI is calculated based on validated monitoring data.

(3) 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.

(4) 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.

Last revision date:05:07 18-06-2018