THE ENVIRONMENT
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Mexico City, sulphur dioxide just over a quarter, nitrogen dioxide and ozone less than half. Ozone levels are better than those found in Chicago, Philadelphia, Geneva, Paris, Atlanta, Houston and Los Angeles; sulphur dioxide levels are better than in Tokyo, Washington DC, Singapore and New York. Nitrogen dioxide levels are better. than in Los Angeles, London, New York and Rome.
Many factories and commercial activities produce air-borne emissions. The EPD operates a range of controls under the Air Pollution Control Ordinance and its subsidiary regulations, including specific controls on furnaces and chimneys, dark smoke emissions, fuel quality, open burning, dust emissions from construction works and benzene emission from petrol filling stations.
Air pollution arouses great public concern, especially when factories are near homes. The department investigated 4 638 complaints of air pollution, and issued 214 legal notices instructing offenders to abate air pollution.
Some large industrial facilities and processes cause more air pollution than others. The Air Pollution Control Ordinance specifies these processes, which must operate under a licence setting out the measures each must adopt to minimise air pollution. The department has implemented this control in phases with most specified processes to be licensed by 1999. By the end of 1999, about 91 per cent of specified process premises had been placed under licensing control in line with the department's target.
Transport
To tackle Hong Kong's air pollution problems, government policy is to apply the most stringent motor vehicle fuel and emission standards, once they become practical and locally available.
All new petrol cars must be fitted with catalytic converters to control emissions. In April, the sale of leaded petrol was banned. Cleaner fuel and tighter emission standards introduced over the past few years have further reduced pollution from vehicles.
Diesel vehicles are major contributors to Hong Kong's vehicle emission problems. Government control strategies include introducing up-to-date emission standards, tightened inspection requirements, and higher penalties on smoky vehicles. New diesel vehicles must meet Euro II standards, which are currently enforced in the European Union. Only a very low sulphur content of 0.05 per cent is permitted in motor diesel fuel. Since April 1998, all new diesel private cars must meet stringent emission standards. This has, in effect, ended the registration of new private cars using diesel.
A scheme for reporting smoky vehicles has been running since 1988. All vehicles reported under the scheme must be examined at a designated test centre to confirm that the vehicle owners have rectified the smoke defects. Since 1995, tighter smoke inspection and more stringent emission standards for new vehicles have been introduced. The 19 test centres conducted about 37 833 tests in 1999. From September 5, smoky vehicles of 5.5 tonnes or below were tested with an advanced method using a chassis dynamometer to check their smoke emissions.
These programmes will contribute to much-needed reductions in health-threatening levels of air pollutants, especially in urban areas, and take many smoky vehicles off the roads. However, if the health-related air quality objectives are to be met, light-