In season of pollution, here is what your air purifier needs to do

The device must clean up particulate matter, allergens and ultra-fine dust particles

As winter sets in, a clutch of cities in north India tops the list of the world’s most polluted places. For millions of residents of these cities, it is the time when the air quality index (AQI) turns "severe" or "hazardous" even. It’s also the time when people start buying air purifiers.

Some popular air purifier brands in India include Dyson, Samsung, Philips, Honeywell, Coway, Sharp, Mi, Kent, Voltas, Carrier, Bluestar, and Havells. Most devices use either charcoal absorbents or mechanical filters. Other techniques include electrostatic, ionizers, ozone, or ultraviolet air filters.

"Air pollution today is not just a health