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.
capital of Sudan, Khartoum - the capital of Sudan located at the confluence of the Blue Nile and White Nile. Nyala - city in Sudan. Port Sudan - port city in Sudan on the Red Sea. Omdurman - a city of Sudan; located in the central Sudan on the White Nile opposite Khartoum. Libyan Desert - the northeastern part of the Sahara Desert in Libya and Egypt and Sudan. Nubian Desert - an arid sandstone plateau in northeastern Sudan between the Nile and the Red Sea.