Author: Antonio Da Roza
The primary piece of legislation on air pollution in Hong Kong is the Air Pollution Control Ordinance (referred to as ‘APCO’).
APCO regulates air pollution through four distinct regimes: the Air Quality Objectives; licensing for polluting processes; air pollution abatement notices, and asbestos control. 
The Air Pollution Control Ordinance at a glance (1)
Number of sections: 101
Number of parts: 9
Number of Schedules: 6
Number of Regulations: 22
Establishes AQOs; licensing regime for polluting processes; power to issue air pollution abatement notices
Four regulatory regimes
Air Quality Objectives (AQOs) are established under Part II of APCO, setting target maximum amounts for levels of seven air pollutants in Hong Kong.
Emissions of air pollution from certain polluting processes, such as metal works, chemical plants, etc., must be licensed under Part IV of APCO. Emissions from electricity generation are specifically licensed under Part IVB of APCO.
There is also a general power under Part III of APCO to issue air pollution abatement notices requiring that the emissions of air pollutants or the polluting process be ceased or reduced
Under APCO, there are also provisions in respect of asbestos control. Asbestos control is the only form of control over indoor air pollution in the Ordinance; the rest of the Ordinance refers to outdoor air pollution.
Regulating fuel content
Provisions on the fuel content of motor vehicles were removed from APCO to a separate set of Regulations in 1994 – see the Air Pollution Control (Motor Vehicle Fuel) Regulations. 
- The legal definition of air pollution
- The Air Quality Objectives
- Licensing under the Air Pollution Control Ordinance
- Indoor air pollution and indoor air pollutants (overview)