Abstract: Rupture path logic methods of detecting, locating and isolating ruptures within a fluid piping system are disclosed, wherein a rupture within a piping system can be detected and isolated based solely upon local pressure and flow rate measurements at individual valves within the system without the need for communication of measured fluid data between valves at various locations throughout the system. A fluid characteristic is determined individually for each valve based upon the pressure and flow rate measurements at the valve, and that fluid characteristic is compared with set point fluid characteristic information to determine whether each valve is on a fluid path between a fluid supply source and a rupture.