AQI Categories in India: What Each CPCB Level Means

The AQI categories in India follow a six level scale from the Central Pollution Control Board, running from Good to Severe. Each level covers a range of numbers between 0 and 500. So, once you know the ranges, a quick glance at your phone tells you how the air outside is likely to feel.

The AQI categories in India, level by level

Also, these bands come from the CPCB’s National Air Quality Index. The document also lists the health impacts linked to each band, which we summarise below in plain words.

Good means minimal impact. Satisfactory may cause minor breathing discomfort to sensitive people. Moderately polluted can cause discomfort to people with lung disease such as asthma, and to children, older adults and people with heart disease.

Poor can cause breathing discomfort on prolonged exposure. Very poor can lead to respiratory illness on prolonged exposure, more strongly for people with lung or heart disease. Severe affects even healthy people, and light physical activity can bring effects.

What the number is made of

Also, the index considers eight pollutants: PM10, PM2.5, nitrogen dioxide, sulphur dioxide, carbon monoxide, ozone, ammonia and lead. The final AQI is the highest of the individual pollutant scores, not an average. So one bad pollutant can push the whole reading up.

Lead cannot be measured in real time, so it only counts in calculations for past days. In winter, PM2.5 and PM10 are often the ones that decide the number.

How to use the reading at home

First, check the number for your own area, because readings vary by station. Then look at the category instead of only the figure. For example, 180 and 220 sit in different bands, which matters more than the small gap.

Also plan around the reading. On Poor or worse days, consider shifting long outdoor exercise to a better hour, and ask a doctor about any personal health concern. So, this guide is not medical advice.

Also, if you use an air purifier, match it to the room. Our guide to air purifier room size and CADR explains how. In winter, also read our checklist on gas geyser safety, since indoor air matters too.

Common mistakes

• Reading only the number and ignoring the category.
• Using a city-wide figure for a neighbourhood that may differ.
• Assuming an app’s scale matches the Indian one; some apps use other national scales.

Quick examples of how to read a number

An AQI of 95 is Satisfactory, so most people can go about their day. A reading of 150 falls under Moderately polluted, which matters more for children, older adults and people with lung or heart disease. A reading of 250 is Poor, and 350 is Very poor. Above 400, the air is Severe for everyone.

Because the bands are wide, a change from 190 to 210 crosses a line even though the gap is small. Meanwhile, a move from 120 to 180 stays in the same band. So, watch the category as well as the trend through the day.

A simple daily routine

First, check your local reading in the morning and again in the evening. Next, note which monitoring station your app uses, because the nearest one is usually the best guide. Then match your plans to the band: normal routine on Good or Satisfactory days, and more care on Poor or worse days.

Also keep indoor habits steady. For instance, wet mopping and regular filter checks on a purifier help keep indoor air cleaner. However, no home step replaces medical advice for anyone with a breathing condition.

FAQ

What is a good AQI in India?

An AQI from 0 to 50 is Good, and 51 to 100 is Satisfactory under the CPCB scale.

What AQI is considered severe in India?

Severe starts above 400 and runs to 500 on the CPCB index.

Which pollutants decide the AQI?

Eight are considered, and the highest sub-index sets the final number, as described in the CPCB index document.