A dual mode medical oxygen delivery system includes an oxygen supply, a first delivery device, and a second delivery device. A connector includes a valve member and defines a first passage extending from a supply port to a first port and a second passage extending from the supply port to a second port. An oxygen supply conduit interconnects the oxygen supply with the supply port. A first delivery conduit interconnects the first port and the first delivery device, and a second delivery conduit interconnects the second port and the second delivery device. The valve member is movable between a first position corresponding to a first operation mode in which the first passage is fluidly open and the second passage is fluidly blocked, and a second position corresponding to a second operation mode in which the first passage is fluidly blocked and the second passage is fluidly open.
