What AQI does and doesn’t tell you in charts – Firstpost

New Delhi and surrounding towns are currently shrouded in dense fog and the air quality is worsening day by day.

Delhi now holds the title of worst global capital with Air Quality Index (AQI) crossing the 400 mark, according to live data from Swiss agency IQAir.

For Delhi residents, this situation is all too familiar. Every winter, they struggle with smog, a dangerous mix of smoke and fog, as cold air traps dust, vehicle emissions and smoke from illegal stubble burning.

Also read: Winter is here: How Delhi is choking on thick smog and bad air

Dense fog has severely affected visibility, causing disruption to flights and train services in and around the capital. On Friday, the Delhi government responded by implementing anti-pollution measures. GRAP Phase III to address alarming AQI levels.

So what does AQI actually represent and how is it calculated? Let’s examine this in more detail.