Should You Exercise Outdoors When the AQI Is High? A Practical India Guide
The same AQI number means different things on the Indian and US scales. How to adjust your walk or workout by CPCB category, what N95 masks can do, and indoor options.
Air Quality
What Size Air Purifier Do You Need? CADR, Ceiling Height and Night-Mode Speed
Size an air purifier by room volume, not floor area: the two-thirds rule explained, cfm vs m³/h, worked examples and the night-mode speed problem.
Air Purifier On, Windows Shut: When Should You Let Fresh Air In?
A purifier cleans particles; a window brings in fresh air. How to decide which you need on a polluted day, and the indoor sources to cut first.