The headquarters building of China Central Television (CCTV) in Beijing is partially obscured by heavy fog on Wednesday. [Photo/China Daily]

However, not all people can afford the high-end machines, which can cost as much as 40,000 yuan, to clean up the air they breathe.

"I won't be buying the machine, some of which cost more than my monthly salary," said Wang Bao, 27, a primary school teacher of physical education in Beijing's Changping district. "It's too much a luxury for me."

The air purifiers can improve the air a little bit but only scratch at the surface of the problem, said Wang Qiuxia, a researcher at the Green Beagle, a non-governmental environmental protection organization based in the capital.

To solve the pollution problem, she said, "as citizens we should monitor the nearby polluting industries, drive less and stop setting off fireworks during the festival, instead of sealing ourselves up in a closed room."

Public concern over air quality has not been diminished by the claims of the Beijing municipal environmental protection bureau, which said that its monitoring data has shown a decline over the past decade in PM 2.5 and PM 10 levels, measures of harmful particulate matter in the air.

"I'm a little bit used to the bad air already," said Wang Yu, 26, a Beijing resident. "A rare clear day is a blessing to me."

Du Shaozhong, deputy director of the Beijing municipal environmental protection bureau, told the media recently that Beijing's actions to cut air pollution include shutting down coal-fired boilers in downtown and forcing polluting vehicles off the road.