Air purifiers show less than adequate performance in tests

Air purifier samples from Panasonic, Mi and Whirlpool showed poor performance purifying some hazardous pollutants, the Shanghai Consumer Council said on Tuesday after performing tests.

The council tested the purifying efficiency for particulate matter, PM2.5, formaldehyde, methylbenzene and ammonia in 19 air purifiers bought from shopping malls and online. Their prices range between 799 yuan (US$116) and 4,996 yuan. 

All the samples were said to have function in purifying formaldehyde. 

The purifying efficiency of formaldehyde using a Panasonic purifier was only 30 percent, just 71 percent of what was marked on the product, and below the national standard of at least 90 percent, according to the council. 

The methylbenzene purifying efficiency of another device branded Mi was lower than grade C, against China's requirements on purifying properties of indoor air purifiers, the council said. 

The council used ammonia as a pollutant to test air purifier performance in deodorization, and two samples from Mi and Whirlpool were rated below grade C.

"Formaldehyde and methylbenzene are major pollutants left in the air after decoration, and consumers now pay more attention to the purifying performance of these organic compounds of air purifiers in addition to particulate matter and PM2.5," said Shen Hao, director of the Shanghai quality supervision and test center of environmental protection products.

The council also conducted a test on 40 masks with the function of filtering tiny pollutants. A sample branded Ludun showed poor performance in breathability.