Abstract: An airbag inflator includes non-azide gas generating propellants, surrounding an ignition device, disposed inside a housing. The gas generating propellants are surrounded by a coolant/filter device having a pressure loss of 0.3×10−2 to 1.5×10−2 kg/cm2 at a flow rate of 100 l/min/cm2. A space is provided between an outer periphery of the coolant/filter device and the housing such that the combustion gas passes through the entire area of the coolant/filter device. The coolant/filter device is also surrounded by a swell suppressing layer which prevents the coolant/filter device from swelling due to a combustion of the gas generating propellants.