an inlet and a return air section terminating at an outlet directing air into the incoming air section from the inlet through the fuel cell stack and into the return air section to provide process air to supply oxidizer to said fuel cell stack and ventilating the one or more components within the enclosure as a result of the air being through the fuel cell 23 the method of any preceding embodiment wherein the outlet is in fluid communication with the one or more components within the enclosure and wherein ventilating the one or more components comprises expelling heated air from the fuel cell from the outlet to ventilate the one or more components via positive pressure ventilation 24 the method of any preceding embodiment wherein the one or more components comprise a stationary or mobile hydrogen storage fuel processor or battery bank 25 the method of any preceding embodiment wherein the inlet is in fluid communication with the one or more components within the enclosure and wherein ventilating the one or more components comprises air into the inlet to extract thermal loading generated from the one or more components and or provide negative pressure ventilation to the one or more components 26 the method of any preceding embodiment the incoming air section and return air section being separated by a duct divider and a.