Abstract: The present invention provides improvements in a device and in a process for reducing the amounts of carbon monoxide and any oxides of nitrogen in an airbag inflated by a pyrotechnic inflator by exposing the combustion gases released by the explosion of the inflator, wherein carbon monoxide has been to a large extent oxidized to carbon dioxide with a first oxidizing agent, to a catalytic activation system of a supported palladium(II) salt in contact with a thermally stable second oxidizing agent, preferably an organic heteropolyanion capable of donating oxygen. In the device, the oxidant and the catalyst are protected by a thin, impermeable sheet from contact with surrounding atmosphere to prevent progressive deactivation prior to use.