Dense fog continued to put life out of gear in the national capital. Air, road and rail traffic was disrupted due to poor visibility. More than 40 domestic and international flights were delayed, and four flights were cancelled.Director of the Meteorological office at the IGI Airport R K Jenamani told AIR that dense fog disrupted flight operations severely in morning today. He said that visibility at the runway dropped to zero, as a result no flight could take off between 5.30 and 10 am. The Met office has predicted that dense fog will continue tomorrow as well.