Every year, as winter sets in and Diwali passes, the same headlines appear: “AQI crosses 400”, “Air quality severe”, “Schools shift online”. Weather apps flash orange and red warnings, and family WhatsApp groups fill with forwards about masks and purifiers.<\/p>\n\n\n\n
But what do these numbers actually mean? Is an AQI of 180 dangerous? Should children play outside at 250? This explainer breaks down India’s air quality levels in simple terms and tells you what your family can do at each stage.<\/p>\n\n\n\n
AQI stands for Air Quality Index<\/strong>. It is a single number, usually from 0 to 500, that tells you how polluted the air is and how it may affect your health. The higher the number, the worse the air.<\/p>\n\n\n\n India’s National Air Quality Index, managed by the Central Pollution Control Board (CPCB), looks at several pollutants, including:<\/p>\n\n\n\n The AQI you see is based on the pollutant that is worst at that moment. In most Indian cities during winter, that is PM2.5 or PM10.<\/p>\n\n\n\n As a simple rule: below 100 is fine for normal life, 100 to 200 calls for care if anyone in your home is sensitive, and above 200 means everyone should cut down on outdoor activity.<\/p>\n\n\n\n Firecrackers add to the problem for a few days, but they are only one part of the story. Several factors come together every winter, especially in North India:<\/p>\n\n\n\n This is why AQI often stays high for weeks, not just on Diwali night. In Delhi-NCR, authorities follow a Graded Response Action Plan that brings in extra restrictions, such as limits on construction, as the AQI worsens.<\/p>\n\n\n\n Use the CPCB’s official Sameer app or the AQI shown in your weather app. Pollution is often worst in the early morning and late evening, so a midday walk may be a better choice.<\/p>\n\n\n\n Cloth and surgical masks do little against fine particles. A well-fitted N95 or N99 mask<\/strong> filters much better. The fit matters: it should seal around your nose and chin without gaps.<\/p>\n\n\n\n A purifier with a HEPA filter<\/strong> can reduce particle levels in a closed room. Choose one rated for your room size, keep it running in the room where you sleep, and change filters on time. Indoor plants look lovely, but they cannot clean polluted air meaningfully on their own.<\/p>\n\n\n\n On poor or worse days, skip outdoor runs and do yoga, stretching or a home workout instead. Our 10-minute morning stretch routine<\/a> is a good indoor option.<\/p>\n\n\n\n\n
India’s AQI levels and what they mean<\/h2>\n\n\n\n
AQI<\/th> Category<\/th> What it means for you<\/th><\/tr><\/thead> 0\u201350<\/td> Good<\/td> Air is clean. Enjoy outdoor activities.<\/td><\/tr> 51\u2013100<\/td> Satisfactory<\/td> Fine for most people. Very sensitive people may notice minor discomfort.<\/td><\/tr> 101\u2013200<\/td> Moderate<\/td> People with asthma, lung or heart conditions, children and older adults may feel discomfort.<\/td><\/tr> 201\u2013300<\/td> Poor<\/td> Long exposure can cause breathing discomfort for most people. Reduce outdoor exercise.<\/td><\/tr> 301\u2013400<\/td> Very poor<\/td> Long exposure can cause respiratory illness. Avoid outdoor exercise and limit time outside.<\/td><\/tr> 401\u2013500<\/td> Severe<\/td> Affects healthy people too and seriously affects those with existing conditions. Stay indoors as much as possible.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n Why does air get worse after Diwali and in winter?<\/h2>\n\n\n\n
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How to protect your family on high-AQI days<\/h2>\n\n\n\n
Check the AQI before you step out<\/h3>\n\n\n\n
Wear the right mask outdoors<\/h3>\n\n\n\n
Keep indoor air cleaner<\/h3>\n\n\n\n
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Consider an air purifier<\/h3>\n\n\n\n
Move your workout indoors<\/h3>\n\n\n\n
Support your body with the basics<\/h3>\n\n\n\n