Cleaning the Air at Street Level

Street Level Air Pollution

In our busy streets, air pollution is mainly caused by motor vehicles, particularly diesel vehicles such as trucks, buses and light buses which emit a large amount of particulates and nitrogen oxides. The pollutants are then often trapped in between the very tall buildings along the streets.

A Comprehensive Vehicle Emissions Control Programme

The Government has been working for years to control emissions from motor vehicles. Although there had been progress made, such as the tightening of vehicle emission standards, the improvements from these measures had tended to be offset by increases in emission from the continue growing vehicle numbers and kilometres driven.

Therefore, in 2000 the Government pressed ahead with an enhanced programme to address the problem. The programme aimed to reduce particulate emissions from motor vehicles by 80% by the end of 2005, and nitrogen oxides emissions by 30%. The main initiatives included :

• Adopt tighter fuel and vehicle emission standards.
• Adopt cleaner alternatives to diesel vehicles where practicable.
• Control emissions from the remaining diesels with devices that trap pollutants.
• Strengthen vehicle emission inspections and enforcement against smoky vehicles.
• Promote better vehicle maintenance and eco-driving habits.

New Initatives in 2007

To strengthen the effort to improve roadside air quality, the Government launched on 1 April 2007 new measures to reduce vehicle emissions:

• Provide a one-off grant to encourage vehicle owners to replace their pre-Euro and Euro I diesel commercial vehicles with new commercial vehicles complying with the prevailing emission requirements for newly registered vehicles, which, at the moment, is Euro IV standard. The grant will last for 18 months for pre-Euro vehicles and three years for Euro I vehicles. The Government earmarked 3.2 billion for this programme.
• Offer a 30% reduction in first registration tax to buyers of newly registered environment-friendly petrol private cars, subject to a ceiling of $50,000 per car.   Environment-friendly petrol private cars emit 50% less hydrocarbons and nitrogen oxides and consume 40% less fuel than conventional Euro IV petrol private cars.

New Initatives in 2008

Starting from 1 April 2008, buyers of newly registered commercial vehicles meeting the qualifying standard for environment-friendly commercial vehicles, which is set at Euro V level, will enjoy concessions for their first registration taxes. Compared with Euro IV vehicles, Euro V heavy duty diesel vehicles emit about 40% less nitrogen oxides (NOx). For light duty diesel vehicles, Euro V models emit about 80% less respirable suspended particulates and 30% less NOx. As regards Euro V petrol/LPG vehicles, they emit about 30% less NOx.

Progress of Major Initiatives

Tighter fuel and vehicle emission standards

Cleaner alternatives to diesel

Taxis - To encourage a quick switch of the 18,000 diesel taxis to environmentally-cleaner vehicles, the government provided a one-off grant of $40,000 for each replacement of diesel taxis with one that operates on liquefied petroleum gas (LPG) in a subsidy programme starting in August 2000. The programme was completed at the end of 2003. Nearly all (about 99.9%) taxis had switched to LPG. 

Light Buses -  We started a programme in August 2002 to offer incentives to encourage the early replacement of the 6000 diesel light buses with LPG or electric ones. For diesel public light buses, we offered a one-off grant of $60,000 or $80,000 for each diesel public light bus that was replaced with an LPG or electric one respectively; for diesel private light buses, each replacement LPG vehicle was exempted from the first registration tax. At present, electric vehicles are exempted from first registration tax. The programme was completed at the end of 2005. Right now, about 58% of the registered public light buses are LPG.

Controlling emissions from the remaining diesels

Particulate reduction devices for pre-Euro light diesel vehicles

Light diesel vehicles - A programme to help owners of pre-Euro light diesel vehicles to retrofit their vehicles with particulate traps or catalytic converters was completed in 2001. More than 80% of the fleet, or 24,000 light diesel vehicles, were fitted with these devices under the retrofit programme. A particulate trap/catalytic converter can cut particulates emission from a pre-Euro light diesel vehicle by about 30%. From December 2003, a regulation requiring all pre-Euro diesel light vehicles up to 4 tonnes to be installed with suitable particulate reduction devices has been implemented.

Medium and heavy diesel vehicles - A programme to help owners of pre-Euro heavy diesel, other than those heavy duty vehicles that require the operation of on-board equipment during idling (i.e. long idling vehicles) which were retrofitted separately in another programme, to retrofit their vehicles with catalytic converters was completed in 2004. More than 96% of the fleet, or 34,000 heavy diesel vehicles, were fitted with catalytic converters under the retrofit programme. A catalytic converter can cut particulates emission from a pre-Euro heavy diesel vehicle by about 25% to 35%. From April 2006, a regulation requiring all these pre-Euro heavy diesel vehicles to be installed with suitable particulate reduction devices has been implemented.

A similar programme to help owners of long idling pre-Euro heavy diesel vehicles (i.e. concrete mixer, gully emptier, lorry crane and pressure tanker) to retrofit their vehicles with catalytic converters was completed in 2005. About 95% of the fleet, or 2,500 long idling pre-Euro heavy diesel vehicles, were fitted with catalytic converters under the retrofit programme. From April 2007, a regulation requiring all these long idling pre-Euro heavy diesel vehicles to be installed with suitable particulate reduction devices has been implemented.

Buses - The bus companies have retrofitted about 2,000 older buses of pre-Euro or Euro 1 models with diesel catalytic converter.

Diesel Particulate Filter (DPF) - Franchised bus companies are retrofitting DPFs to their Euro II and III buses. A DPF can reduce particulate emissions from diesel vehicles by over 80%.

Strengthening emission inspection and enforcement

Controlling Smoky vehicles
The Environmental Protection Department operates a Smoky Vehicle Emission Control Programme that requires smoky vehicles spotted by accredited spotters to undergo a smoke test within a specified period. Failure to pass the test will result in the vehicle licence being cancelled. More than 20,000 vehicle licence cancellations have been recommended since the implementation of the programme in 1988.

To enhance the effectiveness of the Smoky Vehicle Control Programme, we introduced a more advanced emission test: the dynamometer smoke test - for diesel vehicles up to 5.5 tonnes in September 1999. The dynamometer test has been proved to be a more effective smoke testing method. We extended the test to all diesel vehicles in December 2000.

The Police supports the action to control smoky vehicles by mounting roadside smoke-testing operations using a portable smokemeter. Fixed penalty ticket will be issued to the owners of vehicles failing the smoke test. The fixed penalty for smoky vehicle was raised from $450 to $1,000 on 1 December 2000.

Petrol and LPG vehicle emission checks - Since November 2000, all petrol and LPG vehicles have been required to undergo an emission check during their annual roadworthiness test.

Promoting better vehicle maintenance and eco-driving

Training and seminars on vehicle maintenance
Since August 1999, the Environmental Protection Department, in collaboration with the Vocational Training Council and Hong Kong Productivity Council, has been offering training sessions for vehicle mechanics on proper engine repair and maintenance to reduce smoke emissions from diesel vehicles.

As LPG vehicles are relatively new in Hong Kong, seminars are also organised to promote the awareness of their owners on their maintenance.

Campaign on eco-driving
The Government kicked off a campaign in September 2001 to promote "switching off engines while waiting". Guidelines have been issued to the transport trade on this good practice.

Improvements in air quality

We are seeing improvements in air quality with the implemented measures. Compared with 1999, the roadside concentrations of the major air pollutant emissions from vehicles, namely respirable suspended particulates (RSP) and nitrogen oxides (NOx), had been reduced by 15% and 24% respectively in 2007. The number of smoky vehicles on the road has also reduced by about 80%.