Beijing is shrouded under a toxic haze again, as the city enters the fourth and final day of its `red alert`. The measures are aimed at trying to curb the city`s notorious smog. More and more Chinese people are now taking precautions against the air pollution. Beijing resident Li Tianqin, has a three-year-old daughter and has tried many ways to protect her family, including buying a can of fresh air imported from Canada`s Rocky Mountains.