a foil 42 preferably stainless steel burst foil on the inside of the housing when the pressure inside the chambers 36 38 exceeds a given value the foils rupture and the gases escape the inflator through aperatures 16 and 18 which then inflate the air bag not shown eight 8 inflators substantially as described above and in fig2 were constructed wherein the smaller combustion chamber contained 25 grams of ammonium nitrate nitroguanidine gas generant pellets the larger chamber was filled with 35 grams of gas generant compressed knitted 304 stainless steel wire 0 023 34 was placed in the cooling filtration chambers 25 grams in the smaller chamber and 50 grams in the larger chamber the enhancers contained 2 and 4 grams of a conventional enhancer composition respectively the assembled inflators were evaluated in a 60 liter test tank fitted with equipment to record the pressure and time profile the inflators were installed into the tank and ignited the resulting pressure versus time curves are found in fig3 these data clearly indicate that the inventive inflator can provide a broad range of pressures at a given point in time for example using the dual chambered inflator according to the invention a pressure of from 125 to 300 kpa can be delivered at 20 milliseconds ms post ignition this range of pressures can be accomplished through firing the smaller chamber first and then firing the.