An apparatus (4) for controlling the flow of gas (2) into a container (3) comprises: a primary gas conduit (6) configured to feed inert gas from an inert gas source (2) at a pressure greater than atmospheric pressure to a container configured to receive flammable material; a first gas flow regulating means (8) operably connected to the primary gas conduit (6), and configured to regulate the flow of gas flowing therethrough; a secondary gas conduit (10) in fluid communication with the primary gas conduit, and disposed upstream of the first gas flow regulating means (8); gas storage means (20) operably connected to the secondary gas conduit (10), and configured to store a volume of inert gas; and a first valve (14) operably connected to the primary (6) or secondary (10) gas conduit, and disposed upstream of the gas storage means (20). The apparatus (3) is characterised in that it is configured to switch between a standby mode in which the storage means (20) is not in fluid communication with the inert gas source (2), and an activated mode in which the storage means (20) is in fluid communication with the inert gas source (2), and wherein the first flow regulating means (8) is configured to prevent the pressure of the inert gas downstream of the first flow regulating means (8) from exceeding the pressure of the inert gas in the storage means (20).