An exhaust diluting and diffusing apparatus includes a first pipe forming a vertically directed outlet for an exhaust conduit and a second diffuser pipe mounted to receive an exhaust gas flow from the outlet of the first pipe, the second pipe having a diameter greater than the diameter of the first pipe to define an ambient air inlet gap surrounding the outlet of the first pipe, and being sufficiently wide to allow the exhaust gas to expand and diffuse in the second pipe. The device further includes a dispersing outlet mounted at an end of the second pipe and configured to direct exhaust gas radially outward, an area defined by the diffuser outlet being greater than an area of the outlet of the first pipe.