The Chinese mainland customers bought 2.4 million air purifiers in 2013, surging 105.9 percent year-on-year to 5.6 billion yuan ($912 million) sales, according to a March report by the Beijing-based China Center for Information Industry Development.
Huge demand for air purifiers will continue and 19.5 million units is expected to be sold this year, creating a profitable arena for the right kind of company.
Guangdong-based electric appliance firm Midea Group reportedly plans to expand production from 400,000 to 1 million units this year.
Price-sensitive Chinese seem to prefer low-end models. Air purifiers under 1,000 yuan occupied 52 percent of the Chinese mainland market in 2013, the report said.
The drawback is these purifiers do not clean the air as quickly and efficiently as those that cost 3,000 yuan and up, according to a 2013 product review by Beijing tech site ZOL.
But, the drawback of the high-priced purifiers is they require high-cost filter replacements, warned Luo Qingqi, director of domestic market research firm Pa Le Consulting.
Filters need frequent changing, especially in China, Luo said, even though some brands may boast that their filters last for years.
Instead of following fashion or pursuing the lowest price, consumers should focus on the filtration system, energy consumption and air exchange rate, he suggested.
Some retailers overhype their purifiers, he said. "Having one at home does not mean never again needing to open and shut a window."
The air purifier first became popular for removing allergens, but it now has become the most requested home appliance in China.
The ionizer-equipped purifier is the most popular on the Chinese mainland, taking 47 percent of 2013 sales. Consumers often believe this device not only eliminates airborne pollutants, but also generates negative ions beneficial to health.
Consumers should rethink that choice, believes Ding Wanqing, an industry analyst with Shenzhen-based market research firm Qianzhan.
The ionizer emits ozone, which can be toxic and cause lung damage in sufficient quantities, Ding said. The national standard for indoor ozone is 0.16 milligrams per cubic meter.
The high-efficiency particulate absorption (HEPA) filter is regarded as a top pick by professionals around the world, most effective on particles down to 0.3 microns in size, such as mold, pollen and cigarette smoke particles. For those sensitive to smell, activated carbon filter can also do a great job.
IQAir HealthPro 250
IQAir HealthPro 250 14,980 yuan
IQAir is a Swiss company that has long been seeking technology solutions to help people remove airborne pollutants. Its history dates back to 1963. HealthPro 250 is one of the most popular models among the IQAir family and is said to be the first air purifier to help provide severe allergy and asthma sufferers with relief through its patented HyperHEPA technology.
The HyperHEPA filter can help remove particles down to 0.003 microns, about 10 times smaller than a virus. In addition, the HealthPro 250 uses another two filtration techniques - PreMax large-capacity prefilter and V5-Cell filter - to eliminate larger particles like dust or pollen and remove harmful gases.
The unit is one of the most expensive on the market. And maintenance is not cheap either, even though the filters have different replacement schedules
and users exchange them separately by an intelligent reminder. A PreMax filter costs 980 yuan ($160) and lasts 18 months. A HyperHEPA filter costs 2,380 yuan and is designed to last up to four years. The V5-Cell filter should be exchanged approximately every three years at a price of 1,580 yuan.
It can handle a room up to 100 square meters at a maximum air exchange rate of 8.48 cubic meters per minute, but the energy consumption is a low 75 watts. With a user-friendly remote control, users can select from six speed settings at a distance of up to 10 meters. One downside of HealthPro 250 is its noise level, which some users say is intolerable on the lowest setting. Weighing 16 kilograms, the modular-tower-designed device features a body of 410 millimeters by 380 millimeters by 710 millimeters, with caster wheels.
Panasonic F-VXJ90C-SK 5,949 yuan
Japanese electronics producer Panasonic introduced the newest model F-VXJ90C-SK to its air purifier colleague in 2013.
Equipped with a human body sensor, the device can adjust the fan speed automatically. It also has a light sensor, an odor sensor and three-setting moisture sensor. F-VXJ90C-SK combines three filtration technologies including high-efficiency particulate absorption (HEPA), activated carbon deodorizing and nanoe filters.
Nanoe technology generates water ions to add moisture to the air. But users have to wash the nanoe filter every three months and are suggested to exchange it after three years' use at a cost of 269 yuan ($43.8).
The combined filters (499 yuan) can remove chemicals, harmful bacteria and particles down to 0.3 microns in size. They last up to three years. The activated carbon filter also needs replacement every three years at a cost of 219 yuan. The device provides a filter-change alert.
According to some users, the filtered air is fresher and moister, but the unit must rely on people to fill up a water tank and it usually takes half a day to get the air moist.
It is capable of cleaning rooms up to 99 square meters, but takes a fairly long time at a maximum air exchange rate of 7.98 cubic meters per minute. And the energy consumption is high at 88 watts.
To prevent naughty and curious children from playing with the machine, F-VXJ90C-SK owners can press a button for three seconds to lock all buttons.
The stainless steel machine is available in silver and black with dimensions of 398 millimeters by 275 millimeters by 636 millimeters.
Mitsubishi SPS-511AC 3,680 yuan
Based on technologies and experiences amassed via production of aircraft and air conditioning, Japan's Mitsubishi also earns solid feedback for performance of its air purifier series. SPS-511AC is one of the most requested for its quietness and low energy consumption. A full-day operation will only cost 0.1 yuan ($0.02) at the lowest speed.
Embedded with an odor sensor and dust induction behind, the machine can automatically adjust the fan speed. Users can also manually select from four speed settings.
Its maximum air exchange rate reaches 5.1 cubic meters per minute, which can only handle small rooms up to 36 square meters.
Thanks to the three-level filtration system - a combination of prefilter, MS activated carbon filter and BIO HEPA filter - SPS-511AC can eliminate chemicals like formaldehyde and remove particles down to 0.1 microns in size, such as mold, pollen, dust and pet dander. But it needs two hours to remove 99.99 percent of the bacteria.
The filters can last up to 18 months in 24-hour use, and cost 500 yuan ($81.45) in total.
Sporting a body of 340 millimeters by 180 millimeters by 600 millimeters, the unit weighs 6.2 kilograms.
It comes available in white and gold.