Abstract: A diaphragm failure sensing apparatus for use in a diaphragm pump having at least two pumping cavities, each pumping cavity having a fluid chamber and a motive gas chamber separated by a pumping diaphragm. The diaphragm failure sensing apparatus includes a fluid conduit for connection with each of the motive gas chambers of the diaphragm pump, a sensor chamber connected to the fluid conduit, and a check valve located in the fluid conduit for alternately connecting the sensor chamber to the motive gas chambers. Also provided is a diaphragm pump having at least two pumping cavities, each pumping cavity having a fluid chamber and a motive gas chamber separated by a pumping diaphragm. A fluid conduit is disposed between and connected individually to each of the motive gas chambers and a sensor chamber is connected to the fluid conduit which is alternately connected to the motive gas chambers by a check valve located in the fluid conduit.