Why India's Air Quality Index Caps at 500 Despite Toxic Levels

Sun Nov 16 2025 06:08:43 GMT+0200 (Eastern European Standard Time)

Explore the controversy behind India's air quality index, which stops reporting pollution levels at 500, even as toxic air threatens millions. Join the debate on whose numbers to trust for a healthier future!

In northern India, millions battle severe air pollution that feels ashy and hazy in November. Government apps cap air quality readings at 500, while private trackers often report levels above 600 and even 1,000. This discrepancy raises questions about trust in monitoring systems and the reasons behind India's official limits. Experts argue this cap was set to minimize panic despite the reality of worsening air quality. There's also concern that India's air quality standards lag compared to global norms, necessitating a review of their air quality index system.

For millions across northern India, the November air tastes ashy, the sky looks visibly hazy and merely stepping outside feels like a challenge.

Many start their day checking how bad the air is, but it varies depending on which monitor is used.

Government-backed apps like SAFAR and SAMEER top out at 500 - the highest number on India's AQI (air quality index) scale, which measures various pollutants.

In contrast, many private and international trackers report higher figures, sometimes exceeding 600 and even reaching above 1,000.

This contradiction has people questioning which numbers are trustworthy, and why India does not report air quality data beyond 500.

India's government states that readings beyond 500 are not officially reported because it was presumed that the health impact would be similar regardless of how severe conditions got.

The cap was set over a decade ago when the National Air Quality Index was established, aimed at avoiding public panic during alarming pollution levels.

However, this approach flattens critical data, turning reality into a false sense of security.

International organizations do not impose such limits, which leads to discrepancies in reported data.

Experts highlight that both measurement techniques and local adjustable standards play significant roles in the differences in air quality reporting.

The metrics and instruments used also differ; India's pollution control focuses on strict standards while international platforms often rely on sensor-based monitors, which aren’t officially approved in India.

To adapt and truly convey the critical nature of air pollution, environmental experts are calling for an overhaul of India’s AQI standards and the removal of the upper limit on air quality reporting.