Health risk category for Air Quality Health Index may reach Serious Level

     The Environmental Protection Department (EPD) has recorded higher than normal pollution levels since yesterday (Aug 27) afternoon and the situation is expected to continue in the next couple of days. According to the EPD's forecast, it is expected that the AQHI at some general and roadside air quality monitoring stations may reach the "Serious" level later today (Aug 28).

     Hong Kong is affected by a continental airstream with high background pollution. The weather is fine, very hot with light wind which is unfavorable for pollutant dispersion. The sunshine enhances photochemical smog activity and the rapid formation of ozone and fine particulates in the Pearl River Delta region. The high level of ozone has promoted the formation of nitrogen dioxide in parts of the urban areas and at the roadside.

     According to the Hong Kong Observatory, the weather in Hong Kong will remain fine and very hot, and wind will remain light until latter part of next week. It is expected that pollution levels will remain higher than normal in the next couple of days until wind speed strengthens.

     With a health risk category in the "Very High" range or above, children, the elderly and persons with existing heart or respiratory illnesses are advised to reduce physical exertion and outdoor activities to a minimum or avoid such activities. The general public is advised to reduce, or reduce to a minimum, outdoor physical exertion, and to reduce time staying outdoors, especially in areas with heavy traffic. As health effects of air pollutants may vary for individuals, persons who are in doubt or experience discomfort should seek advice from health-care professionals. The public may visit the Centre for Health Protection's website ( for more information on health effects of air pollution and relevant health advice.

     The Education Bureau (EDB) urges all schools to visit the EDB's website for appropriate measures to safeguard students' health and take note of changes in the index. The relevant hyperlink is as follows:

     When the AQHI is at the "Very High" level, employers of outdoor workers performing heavy manual work are advised to assess the risk of outdoor work and take appropriate preventive measures to protect the health of their employees, such as reducing outdoor physical exertion and the time of their stay outdoors, especially in areas with heavy traffic. At the "Serious" level, employers of all outdoor workers are advised to assess the risk of outdoor work and take appropriate preventive measures to protect the health of their employees.

     Members of the public can check the current AQHI readings at the EPD's website ( or by calling the hotline 2827 8541.

Ends/Friday, August 28, 2020
Issued at HKT 10:25