A system and method for providing inerting gas to a protected space. Oxygen is directed from an oxygen source (12) to a motive port (64) of an ejector (18), and air is introduced to a suction port (68) of the ejector. A gas mixture of oxygen and air is directed from an outlet port (73) of the ejector to a reactor, and a reactant is directed from a reactant source (16) to the reactor. Oxygen in the gas mixture is reacted with the reactant to incorporate the oxygen into a non-combustible compound, and an inerting gas comprising the non-combustible compound is directed to the protected space (22).