A gas manifold system includes a plenum that receives a gas at a positive pressure and a manifold having at least one exit port. One or more valves are disposed between the plenum and the manifold. When opened, the valve(s) permit a stream of the gas at positive pressure to flow from the plenum into the manifold. A baffle is disposed in the manifold between the valve(s) and the exit port(s). The baffle obstructs each stream of gas entering the manifold such that the gas is reduced to substantially zero pressure in the manifold at the exit port(s).