Air Quality Objectives (AQO)

The overall policy objective for air quality management in Hong Kong is to achieve as soon as reasonably practicable and to maintain thereafter an acceptable level of air quality to safeguard the health and well being of the community, and to promote the conservation and best use of air in the public interest. In this regard, Air Quality Objectives (AQOs) for seven widespread air pollutants were established in 1987 under the Air Pollution Control Ordinance (APCO) based on international standards as yardsticks for air quality management. These derived from scientific analyses of the relationship between pollutant concentrations in the air and the associated adverse effects of the polluted air on the health of the public. The established AQOs apply to the whole territory.

(Source: EPD, HKSAR Gov't)