The WahoooÂ® Swim Monitor System is a drowning detection system invented for dark water facilities (but undoubtedly usable also in clearer water), that monitors how long submerged swimmers are under water, and then alerts the lifeguard if the situation gets dangerous. First, when a swimmer is submerged for a preset period of time (considered by experts to be “precarious”) a discreet Yellow Alert serves as initial notification of a potential event. If the swimmer remains submerged for an additional preset period of time (considered to be “at risk” by experts), a more urgent Red Alert is indicated.
Simple and effective
Via The Life Files