An exhaust gas diffuser (1) is provided comprising an elongate exhaust gas cylinder (3) with a gas inlet (5) and gas outlet (7) and a primary vortex inducer (9) within the exhaust gas cylinder (3) which transforms the laminar follow of the exhaust gas passing through the exhaust cylinder (3) into a turbulent spinning vortex flow. The diffuser (1) further includes means to provide a flow of ambient temperature atmospheric air from external the exhaust gas cylinder (3) to a position internal the exhaust gas cylinder (3). The flow of ambient temperature atmospheric air mixes with the spinning vortex flow of exhaust gases prior to their release from the gas outlet (7). This serves to cool the exhaust gases significantly and ensures the gases are dispersed in a less concentrated form from the diffuser.
