internal gas pressure is substantially less than a detected pressure of the air residing outside of the enclosure also referred to as atmospheric pressure preferably the input port is implemented as a pressure sensitive one way valve that actuates opens upon less than 0 5 pounds per square inch psi the gas output port 150 is configured to output the internal gases residing inside of the enclosure 110 the gas output port 150 is configured to output the internal gases including smoke and other particulates when the internal gas pressure of those internal gases is substantially greater than the atmospheric pressure of the air residing outside of the enclosure 110 the gas output port 150 resides with a gas output cavity 152 located at a bottom portion of the enclosure 110 preferably the gas output port 150 is implemented as a pressure sensitive one way valve that actuates opens upon a pressure difference of less than 0 5 pounds per square inch an aluminum spacer not shown provides support from gravity to the filters 122 124 located above it and separates the gas output cavity 152 from the remainder of the enclosure 110 optionally a layer of white filter media is disposed between the charcoal filter 124 and the gas output cavity 152 the white filter paper is made from tightly woven cotton or cotton like material that functions as a dust barrier between the granulated charcoal charcoal dust generated within the combustion cavity 174 and the gas output valve 150 disposed within the gas output cavity 152 in some embodiments the portion of the enclosure 110 that surrounds the combustion cavity 174 is made from stainless steel in some embodiments the height of the side surface 114 of the combustion cavity is approximately 1 25 inches optionally a.