The day’s air pollution, not the weather, is arguably the favorite topic of discussion among Hong Kong locals.
For casual observers, the level of pollution on a given day is often determined simply by looking at Victoria Harbor. If the skyscrapers on the other side of the water are not visible and instead shrouded in a gray haze, that is probably a bad day to be breathing.
Of course, there is the government’s Air Pollution Index, a more technical and accurate gauge that residents can check online. It provides a score for the air of various districts, a rating of low to very high levels of pollution and the highest contributing pollutant in a given area, which is often “respirable suspended particulates” or “ozone.”
But some experts say not only does the government’s API, which is based on a system developed by the Environmental Protection Agency in the U.S., use an outdated standard to report pollution severity, but to the public, the figures posted are just that: numbers that are too abstract.
People here “don’t have very strong feelings about the current API because they do not know what it means when the API reaches very high,” said Melonie Chau, the senior environmental affairs officer at the local chapter of Friends of the Earth.
A group of academics have tried to solve this problem, as well as to provide a system that is more accurate and relevant, by developing a new index, based on Canada’s Air Quality Health Index. This new AQHI, which was commissioned by the Hong Kong government, was proposed in 2009 by the scientists but has yet to be implemented.
The index takes pollutant measurements and translates them into more concrete health implications. The idea was to show, almost in real time, the likely rate of hospital admissions attributable to the amount of four pollutants present in the air, which are sulfur dioxide, nitrogen dioxide, ozone and particulate matter.
But most practical for the public, the new index will give advice on lifestyle changes based on pollution conditions outside.