Abstract: An apparatus for monitoring the presence of a patient in a hospital bed including an elongated, thin, generally rectangular base member of insulating flexible material, such as high-density polyethylene foam, having a generally rectangular cutout opening therein, a rectangular, thin, electrically conductive member affixed to each surface of the base, the base serving to normally maintain the conductive elements spaced apart from each other, a plastic cover cemented to the exterior surface of each of the conductive elements, the edges of the plastic cover being sealed around the full periphery of the device, a cable having two conductors, one conductor being attached to each of the conductive members, the device being generally about 4 inches wide and 34 inches long so that it may be positioned under a patient in a hospital bed, the weight of the patient serving to distort the device so that the conductive members are in contact, providing a closed signal, and the device being sufficiently rigid so that in the