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Hong Kong PM2.5 levels

USA EPA

The annual standard for PM2.5 is met whenever the 3 year average of the annual mean PM2.5 concentrations for designated monitoring sites in an area is less than or equal to 15.0 µg/m3.

http://www.epa.gov/pmdesignations/faq.htm

Hong Kong PM2.5 levels (note they deliberately have no monitoring station in Mongkok and Causeway Bay) attached (source HK EPD)

The levels are  2 ½ to 3 times higher than the US legal permissible amount.

PM2.5 is 1/30 the width of a human hair and enters into the lungs unhindered.

Bridge Timeline

Timeline of the Hong Kong-Zhuhai-Macau Bridge Proposal
Year Events
1983 Gordon Wu proposes the idea of the bridge.
1989 Zhuhai publishes the Lingdingyang Bridge program.
1997 China’s central government shows support for the Lingdingyang Bridge program.
2002 (November) Zhu Rongji, the Premier of China at that time, shows support of Wu’s idea.
2003 The Chinese government shows support of the idea.
2003 (July) Donald Tsang, the Chief Secretary for Administration of Hong Kong, goes to Beijing to meet with the Chinese government about the bridge.
2003 (August) The Hong Kong-Zhuhai-Macau Bridge Advance Work Coordination Group was established.
2007 (May) On 17 February 2006, the HK Airport Authority (ie the HK Government as sole shareholder) confirmed it will hold 55% stake in a company that operates the Zhuhai Airport, with the remaining 45% owned by Zhuhai Airport. The company will not own the assets or the liabilities of the airport. HK Government also announces its intention to get involved in the expansion of Nansha. Zhuhai airport serves Chinese Mainland destinations.

2007 May – Seabed feasibility study began.

2008 (August) China’s Central Government, the governments of Guangdong, Hong Kong and Macau agreed to finance 42% of the total costs. The remaining 58% will consist of loans (approximately 22 billion yuan or 3.23 billion US dollars) from Bank of China.[4]
2009 (March) China’s Central Government, Hong Kong and Macau agrees to finance 22% of the total costs. The remaining 78% will consist of loans (approximately 57.3 billion yuan or 8.4 billion US dollars) from a consortium of banks led by the Bank of China.[5]
2009 (December) Construction of the bridge begins. Vice Premier of Chinese Government Li Keqiang took charge of the commencement ceremony.

WHO database of RSP PM2.5 and PM10 particulates with Hong Kong data included (excludes Causeway Bay and Mongkok PM2.5)

download PDF : OAP_database_8_2011SORTEDPM25PM10

The uphill battle to curb idling engines

South China Morning Post — 23 Sept. 2011

We have been waiting far too long for a law on idling engines. What should have been a relatively simple step in the battle against air pollution has been debated for 14 years. Now, legislation is finally on the way. But the law to take effect in December will have far too many exemptions and it will be difficult to enforce. There is good reason to doubt whether it will really make a difference.

The need for an effective law was highlighted by this newspaper’s recent testing of pollution levels at idling engine hot spots such as taxi stands and minibus stops. The carbon monoxide measurements recorded with a hand-held device on a single day last month are, of course, neither comprehensive nor conclusive. But they do provide an indication of the higher levels of air pollution we have to endure in places where there are many engines idling.

A carbon monoxide reading of 23,000 micrograms per cubic metre of air, was recorded on a stretch of Mong Kok’s Tung Choi Street lined by dozens of idling minibuses. That was 10 times the level of a nearby road with flowing traffic and no idling vehicles, and 30 times more than the reading at the district’s air quality monitoring station. At a minibus terminus in Lockhart Road, Causeway Bay, the temperature was 38 degrees Celsius, five higher than at the Observatory. More research is needed, but it is clear that idling engines have a significant impact and the new law must be effective if it is to have any meaning at all.

Legislators’ approval of the law in March followed much wrangling with transport interest groups. The proposals have been watered down so much that we appear to have lost sight of the objective – to curb the idling of engines by motorists. Among the 20 exemptions are taxis at ranks, buses and school vans that contain passengers, and all vehicles when the weather is particularly hot or wet. Drivers will have three minutes grace every hour. Enforcing this law is not going to be easy. It will be interesting to see if this law can really be enforced. The HK$320 penalty, less than for littering, is not much of a deterrent anyway.

The 260 wardens who police traffic will have watching out for idling engine offenders added to their duties. They will be joined by just 18 specially-trained officers. A weak law and inadequate enforcement add up to minimal change in roadside air pollution readings.

Officials, some of whom walked to work to mark No Car Day yesterday, have touted the law as a significant step in our city’s fight against air pollution, but its value is more symbolic. That need not be the case, though, if enforcement of the law is coupled with close monitoring, a thorough assessment of its impact and a determination to get it right.

Idling engines ramp up pollution

South China Morning Post – 19 Sept. 2011

Tests show much higher carbon monoxide levels and hotter temperatures when streets are full of stationary vehicles rather than moving traffic

Streets full of stationary vehicles with their engines running could be 10 times more polluted than busy roads full of slow-moving traffic, new research has revealed.

Such streets could also be warmer than surrounding urban areas by as much as five degrees Celsius, according to a study by the South China Morning Post (SEHK: 0583,announcementsnews) . Environmentalists said the research could provide useful clues as to the effectiveness of a ban on idling engines, which takes effect in December.

Using a handheld device capable of measuring the carbon monoxide level every two seconds, readings were taken in seven streets in Causeway Bay and Mong Kok on the afternoon of August 13, while a very-hot-weather warning was in effect.

A section of Tung Choi Street in Mong Kok between Argyle Street and Fife Street – where dozens of minibuses were idling – had the highest carbon monoxide reading, at 23,223 micrograms per cubic metre of air.

While that was below the maximum level of carbon monoxide set in the government’s air quality objectives, which is 30,000mcg, it was up to 12 times higher than the reading on a stretch of nearby Fife Street, where traffic was sporadic and there were no idling vehicles. It was also 30 times the level recorded by the Environmental Protection Department’s Mong Kok air quality monitoring station, near Nathan Road in Prince Edward, at the time.

At a bus stop on Nathan Road, near Fife Street, the Post recorded a carbon monoxide concentration of 2,450mcg.

Readings were also taken at Lockhart Road, Causeway Bay, between Cannon Street and Percival Street. One side of the road is a minibus terminus and the other is often occupied by private vehicles. The carbon monoxide level there was 8,285mcg, while a maximum temperature of 38 degrees was recorded, 5 degrees higher than at the Observatory.

Dr Lau Ngai-ting, of the environment division at the University of Science and Technology, said the results indicated serious pollution, although other environmental factors could have affected the findings.

James Middleton, from campaign group Clear the Air, said Tung Choi Street was a perfect example of the city’s urban canyon effect, whereby walls of tall buildings prevent pollutants from being dispersed.

But he said poor maintenance of minibuses was also to blame.

“Carbon monoxide can be produced if an appliance hasn’t been properly maintained or serviced regularly. How often do you think Hong Kong minibus owners service their vehicles? The correct answer is zero.”

Middleton said busy areas should be turned into low-emission zones in which only hybrid or electric buses would be allowed.

The Environmental Protection Department said the long-awaited ban on idling engines, first suggested in the 1990s, could cut roadside emissions by 1 per cent and help reduce nuisance to passers-by.

Environmentalists say the effectiveness of the ban will still be difficult to assess because the benefits could be offset by emissions from moving traffic nearby.

Lau said much more sophisticated studies would be needed to ascertain exactly how much of a contribution idling engines made to pollution and to evaluate the effectiveness of the ban on idling engines.

“The pollution may not necessarily come from the idling engine alone, as the moving traffic, the wind speed and direction and the urban topography will all have a role to play,” he said.

Lau said it was difficult to pinpoint why such a high reading was recorded in Tung Choi Street. It might be down to the ageing, slow-moving minibuses spewing more fumes, and also the poor air ventilation at the street, he said.

From December, drivers who leave their engines idling will face a fixed penalty of HK$320.

Air quality has long been a cause of concern for Hong Kong. In May, Chief Executive Donald Tsang Yam-kuen promised to set out new air quality objectives this year to replace the current rules, set in 1987.

Euro 5 and Euro 6 standards: reduction of pollutant emissions from light vehicles

http://europa.eu/legislation_summaries/environment/air_pollution/l28186_en.htm

The European Union is introducing stricter limits on pollutant emissions from light road vehicles, particularly for emissions of nitrogen particulates and oxides. The Regulation also includes measures concerning access to information on vehicles and their components and the possibility of introducing tax incentives.

ACT

Regulation (EC) No 715/2007 of the European Parliament and of the Council of 20 June 2007 on type approval of motor vehicles with respect to emissions from light passenger and commercial vehicles (Euro 5 and Euro 6) and on access to vehicle repair and maintenance information.

SUMMARY

In order to limit pollution caused by road vehicles, this Regulation introduces common requirements for emissions from motor vehicles and their specific replacement parts (Euro 5 and Euro 6 standards). It also lays down measures improving access to information on vehicle repairs and promoting the rapid production of vehicles in compliance with the provisions of the Regulation.

SCOPE

The Regulation covers vehicles of categories M1, M2, N1 and N2, with a reference mass not exceeding 2 610 kg. This includes, among others, passenger vehicles, vans, and commercial vehicles intended for the transport of passengers or goods or certain other specific uses (for example ambulances), which should have positive-ignition engines (petrol, natural gas or liquefied petroleum gas (LPG) or compressed ignition (diesel engines).

Apart from the vehicles mentioned above (which are covered de facto by the Regulation), vehicle manufacturers may request that vehicles intended for the transport of passengers or goods with a reference mass of between 2 610 kg and 2 840 kg should also be included.

In order to limit as much as possible the negative impact of road vehicles on the environment and health, the Regulation covers a wide range of pollutant emissions: carbon monoxide (CO), non-methane hydrocarbons and total hydrocarbons, nitrogen oxides (NOx) and particulates (PM). It covers tailpipe emissions, evaporative emissions and crankcase emissions.

EMISSION LIMITS

There are emission limits for each category of pollutant emissions and for the different types of vehicle listed above. These are detailed in Annex I to the Regulation.

Euro 5 standard

Emissions from diesel vehicles:

  • carbon monoxide: 500 mg/km;
  • particulates: 5 mg/km (80% reduction of emissions in comparison to the Euro 4 standard);
  • nitrogen oxides (NOx): 180 mg/km (20% reduction of emissions in comparison to the Euro 4 standard);
  • combined emissions of hydrocarbons and nitrogen oxides: 230 mg/km.

Emissions from petrol vehicles or those running on natural gas or LPG:

  • carbon monoxide: 1 000 mg/km;
  • non-methane hydrocarbons: 68 mg/km;
  • total hydrocarbons: 100 mg/km;
  • nitrogen oxides (NOx): 60 mg/km (25% reduction of emissions in comparison to the Euro 4 standard);
  • particulates (solely for lean burn direct-injection petrol vehicles): 5 mg/km (introduction of a limit that did not exist for the Euro 4 standard).

In the case of vans and other light commercial vehicles intended for goods transport, the Regulation includes three categories of emission limits, depending on the reference mass of the vehicle: under 1 305 kg, between 1 305 kg and 1 760 kg, and over 1 760 kg. The limits that apply to the last of the three categories also apply to goods transport vehicles (category N2).

Euro 6 Standard

All vehicles equipped with a diesel engine will be required to substantially reduce their emissions of nitrogen oxides as soon as the Euro 6 standard enters into force. For example, emissions from cars and other vehicles intended to be used for transport will be capped at 80 mg/km (an additional reduction of more than 50% compared to the Euro 5 standard). Combined emissions of hydrocarbons and nitrogen oxides from diesel vehicles will also be reduced. These will be capped at, for example, 170 mg/km for cars and other vehicles intended to be used for transport.

Implementation of the standards

As soon as the Euro 5 and Euro 6 standards enter into force, Member States must refuse the approval, registration, sale and introduction of vehicles that do not comply with these emission limits. An additional delay of one year is allowed for goods transport vehicles (category N1, classes II and III, and category N2) and vehicles designed to fulfill specific social needs. Time frame:

  • the Euro 5 standard came into force on 1 September 2009 for the approval of vehicles, and shall apply from 1 January 2011 for the registration and sale of new types of cars;
  • the Euro 6 standard will come into force on 1 September 2014 for the approval of vehicles, and from 1 January 2015 for the registration and sale of new types of cars;

Tax incentives granted by Member States and intended to encourage earlier use of the new limits will be authorised if:

  • they apply for all new vehicles available for sale on the market of a Member State, which meet the requirements of this Regulation before their entry into force;
  • they end on the date the new limits come into force;
  • are worth less than the cost, including fitting, of the devices used on any type of motor vehicle in order to guarantee that the values laid down are not exceeded.

OTHER OBLIGATIONS ON MANUFACTURERS

In addition to complying with the emission limits mentioned above, vehicle manufacturers must also ensure that devices fitted to control pollution are able to last for a distance of 160 000 km. In addition, conformity must be checked for a period of 5 years or over a distance of 100 000 km.

The Commission established committees to devise, before 2 July 2008, procedures, tests and specific requirements for the following:

  • tailpipe emissions, including test cycles, low ambient temperature emissions, emissions at idling speed, exhaust gas opacity, and the proper functioning and regeneration of after- treatment systems;
  • evaporative emissions and crankcase emissions;
  • on-board diagnostic systems and the performance of anti-pollution devices while the vehicle is running;
  • durability of anti-pollution devices, replacement parts for emissions control systems, in-service conformity, conformity of production and technical control;
  • carbon dioxide emissions and fuel consumption;
  • hybrid vehicles;
  • extension of approvals and requirements for small manufacturers;
  • requirements for testing equipment;
  • reference fuels, such as petrol, diesel fuel, gas and biofuels;
  • measuring engine power.

Easy and clear access to information on vehicle repair and maintenance is key to guaranteeing free competition on the internal market for information and repair services. To this end, manufacturers must ensure that independent operators have easy, restriction-free and standardised (particularly in terms of compliance with the OASIS standard) access via the internet to information on the repair and upkeep of vehicles, without discrimination in favour of dealerships and official repair workshops. This obligation covers on-board diagnostic systems and their components, diagnostic tools and testing equipment. Charges for accessing such information are permitted if they are reasonable and proportionate.

BACKGROUND

Although the standards for pollutant emissions have been updated since 1 January 2005 (Euro 4 standard), the EU believes that it is necessary to improve them further, while also considering the implications for the markets and the competitiveness of manufacturers, and the direct and indirect costs for businesses.

This Regulation was drawn up after a wide-ranging consultation with stakeholders. It places the emphasis on reducing emissions of particulates and nitrogen oxides (NOx), particularly for diesel vehicles. It should as a result be possible to achieve marked improvements in health. It should be noted that nitrogen oxides and hydrocarbons are ozone precursors.

Lastly, the Regulation amends Directive 70/156/EEC and Directive 2005/55/EC and will repeal, from 2 January 2013, Directives 70/220/EC, 72/306/EEC, 74/290/EEC, 77/102/EEC, 78/665/EEC, 80/1268/EEC, 83/351/EEC, 88/76/EEC, 88/436/EEC, 89/458/EEC, 91/441/EEC, 93/59/EEC, 94/12/EC, 96/44/EC, 96/69/EC, 98/69/EC, 98/77/EC, 99/100/EC, 99/102/EC, 2001/1/EC, 2001/100/EC, 2002/80/EC, 2003/76/EC and 2004/3/EC.

Clear the Air says: it’s time to get rid of old polluting buses ! Bring in hybrid buses for use in Low Emission Zones on Nathan Rd, Central, Causeway Bay and Kings Road.

http://thestandard.com.hk/newsimage/20110914/5_2011091320594406463bus.jpg

Hong Kong Standard

http://www.orientalmodelbuses.co.uk/Xtra/IMG_0150-big.jpg

Oriental Daily News

http://www.orientalmodelbuses.co.uk/Xtra/IMG_0162-big.jpg

AIR QUALITY IMPACT ASSESSMENT [IN HONG KONG] OF THE HONG KONG-ZHUHAI-MACAU BRIDGE JUDICIAL REVIEW

Download PDF : 110831HZMB_en

Bus stop revamp to ease centre traffic

24 August 2011

http://www.macaudailytimes.com.mo/macau/28771-Bus-stop-revamp-ease-centre-traffic.html

image

From next Sunday traffic in downtown Macau could be easier, said the Transport Bureau, with 21 routes diverted from Avenida de D. João IV and Avenida do Infante D. Henrique

A total of 21 routes will be diverted from some of the busiest bus stops in downtown Macau from August 28 to ease traffic congestion, the Transport Bureau (DSAT) announced yesterday.
Avenida do Infante D. Henrique and Avenida de D. João IV will benefit most from the new measures, which also include an extension of routes MT1, MT2 and MT4 and the creation of a new bus stop near Regency hotel in Taipa.
“I’m sure it [the measures] will be able to cut down on the time it takes for buses to drop off and pick up passengers, as well as to ease traffic congestion,” said the head of DSAT’s Transport Management department, Dick Lo Seng Chi.
From next Sunday routes 3, 4, 6, 18, 18A and 9 will no longer stop at Avenida do Infante D. Henrique, in front of Macau Square. In addition buses 3 and 6 will also no longer stop at the Education and Youth Affairs Bureau (DSEJ) headquarters.
Moreover, routes 23 and 32 will not go through Avenida do Infante D. Henrique and will instead move into Avenida Dr. Mário Soares before continuing to Macau Tower.
The stop at Avenida de D. João IV near the Portuguese School will be less busy as well, with buses 2, 5, 5X, 7 and 10 no longer stopping there.
Route 28 A will also dodge stops at Avenida de D. João IV and DSEJ headquarters and instead continue to the bus hub at Praça Ferreira do Amaral, in front of Lisboa casino.
Finally route 28 B will move straight along Avenida da Praia Grande with a new stop at China Plaza.
Another stop will be created in Estrada Almirante Marques Esparteiro, near Regency hotel, and buses 21A, 22, 24, 25X, 26A, 28A, 33, 50, MT1 and N3 will stop there after crossing Nobre de Carvalho bridge into Taipa.
Also “in response to resident requests” routes MT1, MT2 and MT4 will be extended from its existing terminal at Praça Ferreira do Amaral. While MT1 and MT2 will continue until Praçeta 24 de Junho next to MGM casino and MT4 will go all the way to Praça de Ponte e Horta, at Praia do Manduco.

Reolian improving

New bus operator Reolian is improving its services “much faster than what we had anticipated,” Lo Seng Chi said.
The company “has faced problems and failed to fulfil the bus frequency required,” he acknowledged. But Reolian “has been improving every day” since the new public bus service was launched on August 1, the official stressed.
Still, he added, the operator needs to strengthen the training and attitude of its drivers.
DSAT is especially concerned over reports of conflicts between drivers and passengers. “We have already spoken with Reolian about this issue,” Lo said.
The bureau is also worried about several mechanical breakdowns that affected the company’s vehicles.
“Reolian’s buses are new but they were imported from mainland China and perhaps they are not prepared for the characteristics of the Macau road network,” the official said.
He stressed that most malfunctions occurred going up steep streets. “They should have a technician from the [bus] manufacturer on call to improve the mechanics,” Lo said.
Up until Sunday there were over 120 mechanical breakdowns affecting the buses of all three operators but in most cases the service was not affected. In addition there were 88 accidents with only a few causing injuries.
DSAT has warned new bus operator Reolian that it must provide full services by September 1 or face penalties. Transmac and TCM are currently helping Reolian fulfil some of its busier routes.
“We will see what Reolian’s ability is to boost its services. We have yet to reach a decision on eventual sanctions,” Lo said.

Get rid of polluting vehicles

South China Morning Post – 1 August 2011

Kowloon Motor Bus (KMB) has complained about rising fuel costs and says the government should create a stabilisation fund for the firm. Giving public money to a for-profit enterprise is a dangerous path to take.

However, it seems to me that this debate opens the door to a greater opportunity.

On the one hand, it is true that fuel costs are increasing. On the other hand, bus and minibus fleets are still largely gas-guzzling, pre-Euro V vehicles.

It would seem obvious that it would be of use for the government to spend a few billion dollars that it has in its reserves to upgrade these fleets to hybrid/Euro V vehicles.

This would greatly reduce roadside pollution levels, lower the operational costs for bus operators and benefit all citizens.

Combine this measure with regulations mandating emission levels for vehicles over the long run (10 to 20 years) to avoid operators’ inertia and I think we would have a win-win solution. As a bonus, it would also make redundant the current idling engine legislation, which is virtually unenforceable.

KMB’s responsibility to optimise its routes would still hold if it wanted to compete with other operators.

I would say this is better use of government funds than the HK$6,000 handout to permanent residents.

J. C. Clement, Tai Kok Tsui

Pollution clouds Hong Kong’s future

BBC News – July 31, 2011

Tourist takes pictures against Hong Kong's harbour on July 12.

Visibility in Hong Kong is often affected by pollution

Related Stories

To gaze across Hong Kong’s harbour to the city’s famed skyline of shimmering skyscrapers and lush, green peaks is to experience one of the world’s most spectacular urban landscapes.

When you can see it.

Hong Kong’s “fragrant harbour”, from which the city takes its name, is often obscured by smog.

The city’s air pollution regularly exceeds levels recommended by the World Health Organisation and by some estimates air quality is three times worse than London or New York.

“ It’s only a snapshot but it’s really alarming that our air quality is worse than Beijing and Shanghai” Hak-kan Lai University of Hong Kong

Much of the air pollution is generated by the coal-fired power plants and smoke-stacks across the border in China’s industrial south, but the traffic fumes from the city’s increasingly congested streets also play a large role.

“When I first arrived it was almost as though I could reach out and touch the mountains on the other side of the harbour,” says Rob Chipman, the boss of relocation firm Asian Tigers and the chairman of the American Chamber of Commerce, who has lived in Hong Kong for 25 years.

“It was such a visual treat.”

The city’s worsening air quality is making it harder for businesses to retain and hire international staff, eroding Hong Kong’s appeal as a place to live and work.

A survey of more than 200 international and local companies operating in Hong Kong released in May by the office space provider Regus, suggests that three out of four companies said that the poor air quality was making it harder for them to attract and retain employees from overseas.

It’s not just the wealthier expats that are put off by the poor air quality.

A poll by think tank Civic Exchange in December found that one in four Hong Kong residents is considering emigrating because of air pollution – close to two million people.

Brain drain?

Hong Kongers want the government to do more to improve air quality

To be sure, there is not a mass exodus of workers from Hong Kong because of the poor air quality.

The economy is thriving on Hong Kong’s position as gateway to China. Equally common complaints from companies seeking to attract international staff are sky-high rents and a lack of international school places.

But air pollution does make a difference, particularly in industries such as banking where there are similar jobs in nearby cities like Singapore that have much better air quality.

Australian Sara Foster moved to Singapore from Hong Kong with her toddler son and husband in May and says the difference in air quality is tangible.

Her husband, who works long hours outdoors as a tennis coach, no longer needs to use medication to control his asthma.

“Air pollution was definitely a factor in our move, besides education and job opportunities,” she says.

“You don’t get that heavy smog hanging over the city the way we did in Hong Kong.”

In the American Chamber of Commerce’s latest survey of its members published in January, 68% said air pollution had worsened over the past 12 months and 48% knew of professionals and their families leaving Hong Kong in pursuit of cleaner air.

Room for improvement

“ The government has been weak on this issue and needs to do much, much more if it wants to keep the city competitive in the long term”

End Quote Joanne Ooi Clean Air Network

There are few signs that Hong Kong’s air pollution is improving.

The city’s air pollution index was at the “very high” level – above 101 on the government’s own air pollution index (API) – for 34% of the time during January to March, compared with 11% in the same period in 2010.

At “very high” levels, children, the elderly and those with heart problems are advised to stay indoors.

And campaigners claim Hong Kong’s API is more than 20 years old and permits pollution levels two to four times greater than the maximum levels recommended by WHO guidelines.

Vivian Lee, a 45-year-old receptionist, says her family decided to move to Lantau, one of Hong Kong’s less densely populated islands to escape the poor air.

“It’s really terrible in the city with all the buses and the tall buildings. We wanted to be where the air is fresher,” she says.

In April, according to satellite data analysed by Hak-kan Lai, an assistant professor at the University of Hong Kong, the city has some of the worst air quality in the world.

It ranked fourth worst for air quality out of 17 cities, trailing Guangzhou, Macau and Bangkok.

“It’s only a snapshot but it’s really alarming that our air quality is worse than Beijing and Shanghai,” Mr Lai says.

Blame game

Hong Kong’s skyline on a clear day

Officials have long blamed factories in China for the city’s dirty air, particularly in autumn and winter when prevailing winds blow from the north.

But environmentalists say much of the problem lies closer to home.

Arthur Lau, a researcher at the Hong Kong’s University of Science and Technology, says the city is the main source of its own pollution around half the time, with roadside pollution the main culprit.

Hong Kong has many green areas, with 40% of land reserved for nature conservation and recreation.

But this means most of the city’s seven million residents live and work in less than 25% of the land that is developed, leading to one of the highest traffic densities in the world – 275 vehicles per kilometre.

Roadside pollution is also magnified by a street canyon effect created by the wall-like, high rise buildings that line many of the city’s roads.

Yet the city has no congestion charge or road pricing scheme such as those found in London or Singapore.

Progress?

However, some progress has been made.

The government says it is likely to meet a target to cut emissions of major pollutants, by at least 20% from 1997 levels, by 2010 – largely by retro-fitting the city’s largest coal-fired power plant with emission control devices.

And a law banning drivers from idling engines will take effect in September after 10 years of debate.

But critics say that the law, which allows for 20 exemptions, will do little to ease roadside pollution, which is caused by trucks and buses with outmoded engines.

Drivers caught parked with their engines running will be fined 320 Hong Kong dollars (£26; $41) but the ban will be suspended during very hot or stormy weather.

Cab drivers at taxi stands will also be exempt, as will buses and school vans – and drivers will also be able to idle their engines for three minutes every hour without being charged.

“It will make only a marginal difference, if any,” says Joanne Ooi, of Clean Air Network, a pressure group.

“The government has been weak on this issue and needs to do much, much more if it wants to keep the city competitive in the long term.”