There are three major technology approaches for water purifier companies, he says. These are reverse - osmosis, activated carbon and water softening technologies. Both Bluewater and A. O. Smith have adopted reverse - osmosis technology, as studies indicate that it can filter 99 percent of the pollutants from tap water.

Water purifiers made with this technology account for 35 percent of the market, and have outperformed machines in other categories, says the China Market Monitor study.

The main advantage of the top-end Bluewater model is that it is more efficient, its makers say. While a regular purifier extracts one liter of purified water from five liters, the top-end model extracts one liter from 1.7 liters of water, Wullt says.

Bluewater will initially focus on Beijing and Shanghai before moving on to other Chinese cities, he says, adding that the company has 15 dealerships in Europe and five in the US.

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