Toxic smog chokes Delhi: AQI 500+, GRAP-4 enforced, flights disrupted

• Delhi's Air Quality Index (AQI) reached "severe plus" category, with some areas exceeding 500, amidst dense fog on December 15.
• Dense fog caused low visibility, disrupting morning commute and leading to warnings of flight delays at Delhi Airport.
• GRAP-4 measures were implemented due to severe pollution, banning all construction and demolition activities.
• GRAP-4 also restricts entry of non-essential trucks into Delhi and mandates hybrid schooling for certain classes.

Why It Matters: Delhi's toxic air (AQI 500+) triggers GRAP-4, disrupting travel, health, and daily life.