NEW DELHI: The national capital once again woke up shrouded in a grey haze on Monday, with people gasping, coughing, and complaining. For the past few days, the air quality has plummeted into the “severe” zone, making morning walks into choking marathons. Meanwhile, videos flooding social media showed air purifiers at home coated in thick layers of brown and black dust — reflecting how toxic the air has become. In one viral clip, a man is seen opening his air purifier to reveal a filter coated in thick grime, prompting thousands of horrified comments.Meanwhile, residents of Delhi have taken to the streets to protest. Earlier on Sunday, people gathered at India Gate, many holding placards and inhalers, demanding immediate government action against what they called an “air emergency.” On Monday, the city’s AQI at 6.05 am stood at 346, according to the CPCB, with Bawana topping the charts at a staggering 412. The toxic cocktail of smog and falling temperatures — 11.6°C — has left Delhi and its neighbours Gurgaon and Noida trapped under a chemical fog for the fourth straight day.