Upon the occurrence of a cabin depressurization emergency, a manually operated deployment handle is presented to the passengers in the vicinity of each of the aircraft's supplemental oxygen deployment compartments. A simple manual manipulation of the handle results in the extraction of the individual oxygen masks from the compartment and the activation of the oxygen generating system. In one preferred embodiment, the masks and related oxygen equipment are stowed in an overhead compartment and the manually operated handle is a deployment ring (22) attached by means of a lanyard (24), both to a mask extraction sheath (26) and to an actuator pin (32) associated with the oxygen supply subsystem (20). When the door (10) to the overhead compartment is opened automatically in response to a depressurization signal, the ring falls towards the passenger. When the ring is pulled, the oxygen flow is initiated and at the same time the masks are positively extracted from their stowed position. In an alternative embodiment, the supplemental oxygen compartment is normally concealed by an electrically operated door (110) in the immediate vicinity of the seated passenger. When the door is opened by means of the appropriate electrical signal, one or more oxygen masks (126) are revealed inside the compartment, protected by a transparent barrier (118) to which is attached a handle (120) and a lanyard (122). When the handle is pulled, oxygen commences to flow to the masks in the compartment and at the same time the barrier is removed so that the passenger now has access to the individual masks.