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January, 2010:

Q&A: Hong Kong’s Air-Pollution Problem

New York Times, Reenita Malhotra Hora

13rd, January, 2010

EPA Thick smog hangs over Hong Kong. Air pollution reached dangerous levels one of every eight days in 2009, according to news reports.

The air pollution in Hong Kong reached “life threatening” levels on average one in every eight days in 2009, The South China Morning Post reported in an article that was picked up widely by other news media last week.

According to the report, the “roadside air pollution index” recorded by Hong Kong’s Environmental Protection Department indicated “very high pollution” on at least 44 days in the city’s central district — up from 39 days in 2008.

Green Inc. reached out to Eva Wong, a spokeswoman with the Environmental Protection Department, to discuss the situation. Excerpts from that e-mail exchange are below.


Has the air pollution situation in Hong Kong really become worse in 2009 compared with previous years?


Concentrations of all the major pollutants except ozone in the general (ambient) air reduced in 2009 as compared with 1999. At the roadside, there are also discernible signs of air quality improvements due to the comprehensive vehicle emission control programs taken after 1999.

However, nitrogen dioxide concentration rose by 11 percent in the period.

The rise in nitrogen dioxide concentration at the roadside in 2009 could be explained by the high level of solar radiation and lower than normal rainfall, which favors the photochemical formation of ozone in the region. Hence, 2009 saw a rise in ozone concentration in the ambient air by 10 percent as compared with 2008. The higher ozone concentration is conducive to the oxidation of nitrogen monoxide emitted from vehicles to form nitrogen dioxide, resulting in a higher nitrogen dioxide concentration at the roadside.


Is it true that the air pollution in Hong Kong is already so consistently dangerous that the threshold for severe harm to human health is exceeded almost every day?


The health effects of air pollution vary according to the species of the causing air pollutants and their concentrations.

To alert the public to the health risk posed by air pollution, particularly in the short term, most countries use an air pollution index (A.P.I.), the compilation of which does not have a universal methodology.

In Hong Kong, the A.P.I. system was developed originally based on the former U.S. Pollutants Standards Index system. It is in general comparable with those adopted in other Asian cities, such as Singapore and Taipei. Like the A.P.I. systems in other cities, we provide advice to those more susceptible to air pollution, such as those with heart and respiratory illnesses, to take precautionary measures when the A.P.I. reaches the very high band — i.e., an A.P.I. exceeding the 100 mark.

Apart from emissions, weather conditions affect daily air pollution levels. We usually have good air quality in summer because the summer monsoon brings a cleaner background airstream from the ocean and the air-mixing level is higher favoring the dispersion of pollutants. Our air pollution is higher on days with unfavorable weather conditions that hinder dispersion, or favor photochemical smog formation and when we are under the influence of the continental airstream. Such conditions more often occur in autumn and winter.

On the whole in 2009, the A.P.I. level breached the 100 mark 7 percent to 13 percent of the time at each of our three roadside air-quality monitoring stations.


We understand that Hong Kong’s air-pollution index allows for levels of emissions many times higher than those recommended under the World Health Organization’s Air Quality Guidelines. Can you comment?


Our A.P.I. system makes reference to Hong Kong’s current Air Quality Objectives (A.Q.O.’s). In response to the release of a new air-quality guideline by the WHO, we are in the process of updating our A.Q.O.’s.

We are considering the views gathered from a public consultation on a set of proposed new A.Q.O.’s, which are largely comparable with those of the European Union, and a host of air-quality improvement measures for achieving the proposed new A.Q.O.’s with an aim to deciding how best to take forward the updating.

Meanwhile, we have also commissioned the health experts of the local universities to review our A.P.I. system for better communication of the air-pollution levels and their respective health effects to the public.

No excuse not to switch bus fleet to diesel-electric hybrid models

SCMP, Charlie Chan Wing-tai, Sha Tin

7th Jan, 2010

I read with interest the report (“Roadside pollution a bigger life threat”, January 4).

The severe roadside pollution in Hong Kong is a result of traffic emissions, in particular those from diesel buses.

Even though bus companies have pushed for more environmentally friendly buses over the past few years, there is room for improvement.

As the largest bus operator in Hong Kong, KMB continues to study the feasibility of electric hybrid vehicles and the use of alternative fuels.

In a letter to these columns in 2004, Susanne Ho, the head of corporate communications at KMB, pointed out that the diesel-electric hybrid technology for buses was still in its infancy and was limited to a small number of single-deck prototypes.

She said that issues such as mechanical reliability, battery life, fuel economy, drivability and passenger capacity would need to be improved before diesel-electric technology could be seriously considered for a mass-transit bus fleet that provides reliable services.

However, there has been a rapid advancement of hybrid technology.

Bus operators running hybrid vehicles in London have been unreserved in their praise of the performance, reliability, fuel and CO{-2} reductions being achieved by the single and double-decker made by the firm Alexander Dennis.

Alexander Dennis is one of the main manufacturers of Hong Kong’s double-deckers.

This brand’s single and double-decker hybrid buses are already achieving CO{-2} and fuel reductions of between 35 and 38 per cent in London.

Also, the fleet of hybrid buses operating in Britain’s capital is achieving service availability of 94 per cent, a figure that is steadily increasing.

At the same time, the Greater London Authority has made it clear that it is determined to meet its greenhouse gas targets.

The British government has also made commitments.

It has set up a £30 million (HK$374 million) green bus fund designed to promote the purchase of several hundred new low-carbon buses.

Hong Kong, as a world-class city, must have good air quality.

London has already begun to replace the city’s public buses with a hybrid version.

So when will our government and bus companies follow and eventually catch up with policies being implemented in other international cities?

Dirty, old vehicles in the cross hairs

SCMP, Cheung Chi-fai
5th Jan, 2010

Tougher measures might be considered to phase out old and dirty diesel commercial vehicles given that a voluntary replacement scheme had received a lukewarm response, a senior environment official said yesterday. They could include forcing owners of such vehicles to replace them.

The scheme, which expires at the end of March, provides HK$3.2 billion for cash grants to operators who switch to cleaner vehicles. Since its launch in March 2007, just 13,000 applications have been approved, and of the money, HK$2 billion remains unused. There are still 39,000 of these old diesel vehicles on the road. That is 20,000 fewer than in 2007, but of the 20,000 some 5,800 have simply been deregistered by their owners.

The vehicles are classified as pre-Euro or Euro I, meaning they were built either before the European Union introduced its first (Euro I) restrictions on truck and bus exhaust emissions in 1992, or before they were tightened in 1996. The current Euro V standards are between 62 per cent and 94 per cent tighter than Euro I standards.

Dr Kitty Poon Kit, acting Secretary for the Environment, told the Legislative Council’s subcommittee on improving air quality the government had written to owners of these remaining vehicles reminding them to submit applications for grants under the scheme soon.

However, she said it was not known how many more owners would take up the offer given that the economic downturn had hit the transport sector hard.

Poon said that, as well as the “carrot” of replacement grants, the government would consider wielding a stick – by compelling owners to scrap their polluting vehicles. However, she ruled out the administration buying the vehicles. Last year lawmakers rejected a proposal to increase licence fees for older vehicles, citing the economic downturn.