A double chambered transfer mattress (2) is provided capable of partial deflation that includes a top inflatable mattress and a bottom inflatable mattress that are separated by a common wall (5) from one another. A selectable inlet/outlet valve (50,34) is arranged for airflow communication between an interior chamber of the top inflatable mattress and a source of pressurized air. A one-way valve (31) is positioned through the common wall (5) so as to provide selective air flow communication between the top inflatable mattress and the bottom inflatable mattress so that when the inlet/outlet valve is closed, air continues to escape from perforations in the bottom inflatable mattress and the one-way valve is actuated so as to prevent deflation of the top inflatable mattress.
