New Delhi, Nov. 10 -- When I think about buying an air purifier, its ability to clean the air is obviously the first thing I consider. However, I also want to know how polluted my room is and if the purifier is actually making a difference. This is where an air purifier with an AQI display becomes useful, as it gives a quick indication of indoor air quality without having to rely on a separate monitoring device.

These purifiers can show changes in air quality and, in some models, automatically adjust fan speed based on detected pollution levels. If you are planning to buy one, I would pay attention to its sensors, filtration system and room coverage, along with how clearly it displays air quality information.

The Dyson HushJet Purifier ...