Air contamination levels in the national capital kept on being ‘serious’ as thick brown haze inundated the city, prompting delays in flight and prepare administrations. H ere’s what is going on ground today: Thick exhaust cloud kept on immersing Delhi and the National Capital Region for the fourth day today, with perceivability dropping by 600 meters in the traverse of three hours at the beginning of today. Specialists said that brown haze is mix of smoke and mist. “It was certainly mist, yet not exhaust cloud. For brown haze, you require smoke noticeable all around. For smoke, nearness of gasses, for example, sulfur dioxide (SO2) in high measurements noticeable all around is an absolute necessity. Being acidic in nature, SO2 responds and shapes complex mixes which helps in the development of mist,” said D Saha leader of the air quality lab at Central Pollution Control Board. The levels of SO2 have, in any case, dropped in the course of recent months in Delhi for a few reasons, for example, witching over to clean fills under BS1V, closing down of energy plants, prohibiting of heater oil and pet coke among others. While the allowable furthest reaches of S02 is 80 micrograms for every meter 3D square, in Delhi it is well underneath the utmost. In Anand Vihar, generally considered a “contamination hotspot”, the level of SO2 was around 13.8 micrograms for each meter-solid shape. “Aside from the typical guilty parties, for example, SO2, different gasses and components, for example, sediment and natural gasses, for example, benzene, toluene and formaldehyde likewise help in framing smoke. The primary sources are consuming of non-renewable energy sources and ventures,” said SN Tripathi, facilitator of the Center for Environmental Science and Engineering at IIT Kanpur.