An apparatus having a radiant heater, an upwardly convex reflector, a vertically-oriented cylindrical ring shield joined to the reflector at the outside reflector diameter, an upwardly convex metal hood, and an upwardly convex cap having a cap diameter greater than the diameter of a hood opening, wherein exhaust gases emitted upwardly from the exhaust port draw cooler air through the cylindrical opening, the exhaust gases and cooler air pass upward through the hood, drawing additional cooler air through the annular space between the reflector and the hood, into a mixing chamber formed by the cap and the hood, where the cooler air and the exhaust gases mix and the mixed air and exhaust gases then pass outward through the annular space between the cap and the hood, exiting the apparatus at the outer diameter of the cap.