Hong Kong, with its relatively good quality of living, ranked as the third most livable city among 49 Asian cities for expatriate employees in 2012, up from the fifth place in 2011, following Singapore and Japan's Kobe, according to a survey released on Tuesday.

However, Hong Kong's rise in the ranking was not the result of any improvement in the quality of living here. "Unfortunately, it's been due to deterioration in the quality of living elsewhere," said Lee Quane, regional director, Asia, of ECA International, a human resource consulting company that initiated this annual survey.

Quane explained in a press briefing that Hong Kong came third after overtaking Japan's Tokyo and Yokohama, which both dropped one place in the ranking as inevitable fallout from the devastating earthquake and tsunami hitting Japan in March 2011.

Meanwhile, Hong Kong still has a relatively good quality of living compared to other locations in Asia, Quane added. The survey, conducted by this Britain-based company, has 49 Asian cities assessed under ten categories including climate, health risks, air pollution, goods and services, infrastructure, housing, education and so on.

Singapore maintained the number one spot in the ranking, with its good air quality, solid infrastructure and healthcare facilities, low crime and low health risks. "Other cities are unlikely to take first place from Singapore in the near future," Quane said.

Compared with Singapore, Hong Kong, almost equally good in infrastructure, goods and services, and housing, is believed more affected by natural disasters like typhoon, which will have an impact on people's daily lifestyle. "But Hong Kong's main issue that really separates it from Singapore is its air pollution, " Quane said.

Scoring most in line with Singapore in most factors, Hong Kong's air quality was among the least favorable, compared with places like New Delhi and other developing locations that are prone to poor air quality. "This is where Hong Kong really fails," Quane said.

Meanwhile, scores remain steady among Chinese mainland cities, though ranking far below Hong Kong. Shanghai, ranked 12th, was the most livable of mainland locations, followed by Beijing, Nanjing and Guangzhou. Infrastructures, goods and services, and air pollution are among the fields where the Chinese cities should put more efforts, according to the survey.