Why is India's Air Quality Index capped at 500?

According to experts, the 500 cap on India's official air quality index was originally introduced to avoid creating panic when pollution levels became alarmingly high, but this approach effectively flattens the data and treats anything above 500 the same on official monitors.

How do India's air quality standards differ from global standards?

While the World Health Organization considers PM2.5 levels above 15 micrograms per cubic meter as hazardous, India's threshold is set at 60 micrograms. Experts say comparing India's Air Quality Index to global standards can be misleading, as each country has built its own index based on local factors.

What are the concerns raised by experts about India's air quality monitoring?

Experts say that India's official air quality monitoring system caps readings at 500, despite real-world pollution levels being much higher. This artificial threshold leaves the public unsure about which numbers to trust, and they argue that the government needs to address this issue.

Home / Environment / India's Air Quality Index Capped at 500, Experts Raise Concerns

India's Air Quality Index Capped at 500, Experts Raise Concerns

16 Nov

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Summary

India's official air quality scale caps readings at 500, despite higher real-world levels
Experts say the 500 cap was introduced to avoid panic, but it flattens the data
Differences in defining "hazardous" air quality between India and global standards

India's Air Quality Index Capped at 500, Experts Raise Concerns

In November 2025, India's official air quality monitoring system continues to face scrutiny over its capping of readings at 500, despite experts saying real-world pollution levels can be significantly higher.

The National Air Quality Index, launched over a decade ago, classifies readings above 400 as "severe" and harmful to both healthy individuals and those with existing medical conditions. However, the index does not go beyond 500, a threshold that was originally set to avoid creating panic when the situation became alarmingly bad.

Gufran Beig, the founder director of SAFAR, admits that this approach effectively flattens the data, treating anything above 500 the same on official monitors. In contrast, international organizations and portals do not impose such a cap, leading to much higher numbers being reported on global platforms.