The purpose of an air gap is not really to allow air to escape but rather to keep dirty water from back flowing into the DW. An autovent allows air into the system to allow for proper drainage and an air gap is not dependant on one or vice versa. The autovent takes the place of a vent stack to the roof.
Sudan is a member of the United Nations, the African Union, the Arab League, the Organisation of Islamic Cooperation and the Non-Aligned Movement, as well as an observer in the World Trade Organization. Its capital is Khartoum, the political, cultural and commercial centre of the nation.
Population of Sudan 2014. As of 1 January 2015, the population of Sudan was estimated to be 40 035 397 people. This is an increase of 2.48 % (969 994 people) compared to population of 39 065 403 the year before.