A sensor for sensing the integrity of a pressure relief device, along with associated systems and methods, are disclosed. The sensor may sense a designed area of weakness of a pressure relief device, such as an explosion vent or rupture disk. A monitor may monitor a signal from the sensor, which may be transmitted between the sensor and monitor by way of a sensor loop. In response to a change in the designed area of weakness, the signal from the sensor may be altered or interrupted, indicating that the designed area of weakness has changed. The signal from the sensor may be, for example, an electrical signal, optical signal, or an air flow in a pneumatic loop.