The ‘very poor’ air quality can lead to illness, while ‘severe’ threatens even the healthier lot. As per India Meteorological Department (IMD), the visibility would continue dropping due to the smog. The city on Wednesday was yet again shrouded in smog with particles in the air due pollution. “The visibility would drop further and expected to come down to 150 meters on Thursday. On Wednesday, the visibility at Safdarjung dropped by 500 meters between 2.30 pm and 5 pm,” said an IMD official said.

Meanwhile, more than 60 flights were affected on Wednesday at the airport here, with nearly 50 of them getting delayed as a thick blanket of fog engulfed the national capital.

Around 15 flights were diverted and one was cancelled even as Low Visibility Procedures were implemented at the airport, officials said.

As many as 47 flights were delayed due to bad weather that caused poor visibility conditions in the morning. The situation normalised later, they added.