An aspirator for use in an aircraft evacuation inflatable device inflation system. The aspirator includes: a barrel; a first inlet configured to receive a primary flow of pressurized gas a first pressure P1 during inflation of the aircraft evacuation inflatable device; a second inlet configured to a secondary flow in the form of atmospheric air; and a pressure release valve and interlock combination attached to the barrel. The interlock receives the primary flow and a downstream flow from the barrel, wherein the interlock causes the pressure release valve (PRV) to remain closed during an initial phase of inflation of aircraft evacuation inflatable device.