Abstract: A warning system, the system having a trigger part, a receiver part, and a transmitter part. The system is provided at a first location, wherein the trigger part is physically separate from the receiver part and transmitter part, wherein the trigger part has a signal emitter to provide a signal to the receiver part upon immersion in water, the receiver part receiving signals from the trigger part and providing a further signal to the transmitter part to automatically cause a further warning signal to be emitted by the system, the further warning signal being sent to one or more other locations.