Gas/Air intrusion is typically split into two categories: discharge and suction piping. As it relates to discharge piping, gas intrusion can potentially lead to a water hammer transient. The suction side is more challenging to define since more uncertainty is associated with the computational tools currently available in the industry. The uncertainty increases with the system’s complexity when such features as Tee junctions are considered. Gas could be introduced into the piping through multiple methods, including entrainment of air due to formation of a vortex. Sometimes there is no better alternative than a scaled experiment to simulate the system to demonstrate if-and-when intrusion occurs, and to identify possible remedies. One example is suppression of a gas/air vortex in a containment sump, which was tested in the Fauske lab and let to the development of a vortex suppression device.