The national capital is facing the worst smog in 17 years. This was stated by the Centre for Science and Environment (CSE) today. <br/><br/>It asked the Delhi government to issue health alerts and convey that children should stay indoors as there is a state of health emergency due to peaking air pollution.<br/><br/>As visibility remained poor and the city choked due to a haze, CSE asked the Delhi government to roll out stringent plans for controlling winter pollution from all sources of pollutants and issue daily health advisory to the people.<br/><br/>CSE said that according to the Indian Meteorological Department, Indira Gandhi International Airport recorded the worst levels of smog in 17 years with visibility as low as 300-400 metres yesterday.<br/><br/>According to air quality monitoring network pollution levels are in severe category and are expected to remain in this category for more than three days.