Abstract: A horizontal combined air intake and combustion gas vent terminal assembly is provided having improved wind pressure response and anti-recirculation characteristics. The terminal has a vent conduit disposed inside an air intake conduit. A scoop assembly is provided at the intake conduit inlet to increase the intake air pressure at the inlet. The vent conduit is nozzle-like to throttle combustion gases, thereby accelerating the gases and permitting the terminal to project the gases away from the intake conduit terminal. Vent conduit is disposed asymmetrically with intake conduit to further discourage mixing of intake air and combustion gases. The terminal may also be provided with a static pressure measuring means to provide an intrinsic safety shut down system within the terminal in case of blockage of the intake or vent by snow, ice or other debris.