 The over-wing exits on the Airbus A320 series, Airbus A380, Boeing 747, Boeing 757 and Boeing 767 aircraft use ramp slides in various configurations.Slides can be single or dual lane, depending on the width of the exit they are fitted to and in testing must show a nominal exit rate of 70 people per minute per lane.A dual lane slide is one that is capable of carrying two parallel lines of evacuees and is typically used at the main doors on Widebody aircraft.