Abstract: A leakage detection device is provided for a fluid supply system. The detection device includes control means which can be selectively operated to close a valve and hence prevent further supply. The device includes at least one sensor which senses the flow of fluid through the supply system. Thus the device allows detection of fluid leakage and flow rates and can prevent or limit damage caused by fluid leakage.

Abstract: A wireless, battery-operated detection system of a plurality of RF-interconnected detectors is operable over a CSMA-type network and intended to detect the occurrence of a local phenomena and transmit at least one signal to at least one other detector to remotely sound an alarm. Each detector includes a sensor for sensing local phenomena, a transmitter for transmitting RF messages indicative of the phenomena, a receiver for receiving the RF messages, an alarm circuit for sounding an audible alarm indicative of the phenomena and a controller operable to control the mode of operation of each detector, wherein each controller is operable to control all the detectors in the system in response to a stimulus and to control multiple and conflicting signals transmitted among the detectors. The controller includes a prioritization circuit for determining the relative priority of the received RF signals and stimuli indicative of a particular condition to enable the appropriate mode of operation.