An inflator (10) for use in an inflatable vehicle occupant protection system is provided. In one aspect of the invention, the inflator (10) includes a longitudinal enclosure (22) having a substantially uniform cross-sectional area along at least a portion of the enclosure, and a gas generant composition (24) positioned along the portion of the enclosure (22). The gas generant composition (24) is distributed substantially uniformly along the portion of the enclosure (22). A plurality of gas exit apertures (40) is formed along the portion of the enclosure (22) to enable fluid communication between the enclosure (22) and an exterior of the enclosure. The apertures (40) are spaced apart a distance proportional to a desired rate of propagation of a combustion reaction of gas generant positioned between the apertures (40). In another aspect of the invention, the total number of apertures (40) along the enclosure (22) is inversely proportional to a desired rate of propagation of a combustion reaction of gas generant positioned between the apertures (40). In yet another aspect of the invention, an airbag device is disclosed which includes an inflator having an inflator housing (12) configured as a structural member of a vehicle. The inflator housing may be employed as a stand-alone structural member in a vehicle or used to reinforce another structural member. The housing may comprise a cavity portion having a cylindrical cross-section. The cavity portion may serve as the structural member, or extensions (150) may be coupled to the cavity portion to provide a structural member having a desired configuration. Examples of vehicle components employing the inflator (22) as a structural enhancement include seats, doors, and instrument panels.