Inventor's award-winning face-mask filter will help you breathe easy

Hong Kong's grey, polluted skies may be a health hazard, but for one inventor, they've been an inspiration.

Polytechnic University's Professor Wallace Leung Woon-fong has invented the first multilayer nanofibre filter to purify the air.

"I was in the United States for more than 30 years, seeing blue skies every day. But after I returned to Hong Kong, I could see only grey skies," said Leung, the university's chair professor of innovative products and technologies. "I asked myself: 'What can I do to help Hongkongers?"

So Leung set out to improve the quality of air that people in Hong Kong breathe.

His filter is five times more effective than a conventional surgical mask when it comes to filtering ultra small pollutants of less than 300 nanometres, such as diesel particulates, laser-printer particles, viruses and small bacteria that are easily inhaled.

The filter's multilayer design also allows mask wearers to breathe more comfortably.

That's not all. The filter is capable of breaking down gaseous pollutants, such as volatile organic compounds, to harmless substances under daylight.